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Administrative data

Description of key information

Weight of evidence. Experimental results from short and long-term repeated dose toxicity studies performed with the test substance and some analogues are available:

Diundecyl phthalate (DUP): In one study following repeated exposure over 21 days, DUP was demonstrated to cause moderate proliferation of peroxisomes in the liver of rats. In a 28-d repeated dose toxicity study following method similar to OECD guideline 407, effects in sperm count and sperm motility of Sprague-Dawley male rats were observed at a dose of 500 mg/kg bw/day.

Diisononyl phthalate (DINP): combined chronic toxicity/carcinogenicity following method similar to OECD guideline 453. Based on the read-across approach, the NOEL of DUP is determined to be 19.28 mg/kg/day in a 2-year chronic toxicity study with rats.

Diisononyl phthalate (DINP): 13-weeks repeated dose toxicity study in marmosets following method similar to OECD guideline 409. Based on the read-across approach, the NOEL of DUP is calculated to be 567.02 mg/kg/day.

Diisodecyl phthalate (DIDP): 13-weeks repeated dose toxicity studies with rats and dogs. Based on the read-across approach, the NOEL of DUP is calculated to be 79.71 mg/kg bw/day in dogs and 159.42

mg/kg bw/day in rats.

In a weight of evidence approach the key study was selected to be the 2 -year toxicity study performed with DINP for DNEL derivation since it represents the longest study period and also has demonstrated to be a good quality with reliable data.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Referenceopen allclose all

Endpoint:
short-term repeated dose toxicity: oral
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
March 1984 and February 1985
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
documentation insufficient for assessment
Remarks:
Description of the method is not provided.
Principles of method if other than guideline:
- Principle of test: DUP was tested for its ability to produce peroxisome proliferation in the Fischer 344 rat.
- Short description of test conditions: Samples were taken from the liver of sacrificed animals and prepared for both light and electron microscopy. No details of the test method were provided.
- Parameters analysed / observed: Serum samples were assayed for both triglyceride and cholesterol. The remaining portion of the liver was homogenized and assayed for cyanide-insensitive palmitoyl-CoA oxidation, lauric acid 11-hydroxylase and lauric acid 12-hydroxylase.
GLP compliance:
not specified
Limit test:
no
Species:
rat
Strain:
Fischer 344
Sex:
male/female
Route of administration:
oral: feed
Vehicle:
unchanged (no vehicle)
Details on oral exposure:
DIET PREPARATION
- Rate of preparation of diet (frequency): Once for the 21d treatment period
Analytical verification of doses or concentrations:
yes
Duration of treatment / exposure:
21 days
Frequency of treatment:
Continuously
Dose / conc.:
0 other: %
Remarks:
nominal in diet
Dose / conc.:
0.3 other: %
Remarks:
nominal in diet
Dose / conc.:
1.2 other: %
Remarks:
nominal in diet
Dose / conc.:
2.5 other: %
Remarks:
nominal in diet
No. of animals per sex per dose:
5
Control animals:
yes, concurrent vehicle
Details on study design:
- Dose selection rationale: Based on previous studies with DEHP performed at BIBRA.
Positive control:
di(2-ethylhexyl)phthalate (DEHP) at dietary concentration of 1.2% was used as internal study control.
Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule:
BODY WEIGHT: Yes
- Time schedule for examinations:

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at necropsy
- Animals fasted: Yes
- How many animals: all
- Parameters examined. serum triglycerides & total cholesterol
Sacrifice and pathology:
GROSS PATHOLOGY: Yes

HISTOPATHOLOGY: Yes

Other examinations:
Biochemical analysis of the liver:
Transmission electron microscopy
Cyanide-insensitive palmitoyl-CoA oxidation was measured by the method of Gray et al. (1983). Lauric acid 11- and 12-hydroxylases were measured in washed microsomal preparations (Lake et al., 1984).
Clinical signs:
no effects observed
Description (incidence and severity):
No clinical signs attributed to treatment.
Mortality:
no mortality observed
Description (incidence):
No deaths occurred during the study.
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
Reduction in body weight gains was observed compared to the controls.
Food consumption and compound intake (if feeding study):
no effects observed
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
not examined
Haematological findings:
not examined
Clinical biochemistry findings:
effects observed, treatment-related
Description (incidence and severity):
Serum triglyceride & cholesterol levels in DUP treated male rats were lower than the controls.
Urinalysis findings:
not examined
Behaviour (functional findings):
not specified
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
effects observed, treatment-related
Description (incidence and severity):
Liver weight (absolute & relative) in rats given DUP were significantly higher than those of controls.

Gross pathological findings:
no effects observed
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
not specified
Histopathological findings: neoplastic:
not specified
Other effects:
effects observed, treatment-related
Description (incidence and severity):
Hepatic enzyme levels: There was a significant increase in cyanide insensitive palmitoyl-CoA oxidation and significant increases of lauric acid 11 and 12 hydroxylase activities.
Electron microscopy: there was a moderate increase in peroxisomes.
Key result
Dose descriptor:
NOAEL
Based on:
test mat.
Sex:
male/female
Remarks on result:
not determinable
Key result
Critical effects observed:
not specified
Conclusions:
The substance caused a moderate proliferation of peroxisomes in the liver of rats following repeated exposure over 21 days. This is in agreement with effects described with other phthalate esters.

Executive summary:

DUP was tested for its ability to produce peroxisome proliferation in Fischer 344 rats. DUP was administered in the diet of 5 females and 5 males per group for a period of 21 days at levels of 2.5%, 1.2% and 0.3%. DEHP at dose of 1.2% was used as a study control group as well as a negative (undosed) control group. The rats given DEHP responded as expected to a known peroxisome proliferator therefore the results obtained with DUP were regarded as valid. The electron microscopic examination of samples of liver from rats showed it to cause a moderate proliferation of peroxisomes. This was accompanied to various extents at all dose levels by, changes in other measurements that have been associated with peroxisome stimulation. These measurements were liver weight increases (absolute and relative to bodyweight), greater activities of palmitoyl CoA oxidation and lauric acid hydroxylation and, in males, lower concentrations of serum triglycerides and cholesterol.

Endpoint:
sub-chronic toxicity: oral
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 409 (Repeated Dose 90-Day Oral Toxicity Study in Non-Rodents)
GLP compliance:
not specified
Remarks:
This information was not reported
Limit test:
no
Species:
monkey
Strain:
Marmoset
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Harlan UK (Orfordshire, England)
- Age at study initiation: 15-25 months
- Weight at study initiation: 314-462 g
- Fasting period before study: not specified
- Housing: individually. Cages: Aluminium cages with grid floors suspended above metal trays containing wood shavings.
- Diet (e.g. ad libitum): 10 g of malt loaf, 25 g of pelleted primate diet, Mazuri (Special Diets Services Ltd., England) together with 65 g of fresh fruit each day. Available at all times except when urine was being collected or overnight before bllod sampling.
- Water (e.g. ad libitum): Diet was moistened with 15 mL of water except for one day each week when it was moistened with 15 mL Cytacon solution (a vitamin B12 supplement). Available at all times except when urine was being collected or overnight before bllod sampling.
- Acclimation period: 3 weeks

ENVIRONMENTAL CONDITIONS
- Temperature (ºC): 24
- Humidity (%): 65
- Air changes (per hr): at least 10
- Photoperiod (hrs dark / hrs light): 10/14

Route of administration:
oral: gavage
Vehicle:
other: 1% methylcellulose plus 0.5% Tween
Details on oral exposure:
PREPARATION OF DOSING SOLUTIONS: The DINP solutions were prepared for administration as a series of graded concentrations in 1% methylcellulose plus 0.5 % Tween dosing solutions.

VEHICLE
- Concentration in vehicle (mg/ml): 20, 100, 500
- Amount of vehicle (if gavage): 5 ml/kg bw/d

Analytical verification of doses or concentrations:
not specified
Duration of treatment / exposure:
13 weeks
Frequency of treatment:
daily
Dose / conc.:
0 mg/kg bw/day (actual dose received)
Dose / conc.:
100 mg/kg bw/day (actual dose received)
Dose / conc.:
500 mg/kg bw/day (actual dose received)
Dose / conc.:
2 500 mg/kg bw/day (actual dose received)
No. of animals per sex per dose:
4
Control animals:
yes
Positive control:
Clofibrate administered at dosage of 500 mg/kg bw/d
Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: not specified

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): yes
- Time schedule for examinations: daily.

FOOD EFFICIENCY: No

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No

OPHTHALMOSCOPIC EXAMINATION: yes
- Time schedule for examinations: before commencement of treatment and during Week 12 of treatment
- Dose groups that were examined: all.

HAEMATOLOGY: Yes
- Time schedule for collection of blood: before commencement of treatment and during Weeks 6 and 13 of treatment.
- How many animals: all.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: before commencement of treatment and during Weeks 4 and 13 of treatment.
- How many animals: all.

URINALYSIS: Yes
- Time schedule for collection of urine: before commencement of treatment and during Weeks 5 and 12 of treatment.

OTHER: Before commencement and during Week 12 of treatment additional blood samples were collected for analysis of following parameters: oestradiol and testosterone.



Sacrifice and pathology:
GROSS PATHOLOGY: Yes

HISTOPATHOLOGY: Yes



Other examinations:
Peroxisome proliferation: immediately after removal and weighing of the liver, samples (minimum 5 g) were taken from all animals killed on completion of the 13 week treatment period and frozen by immersion in liquid nitrogen and stored at approximately -75°C until analyzed for protein concentration, cyanide-insensitive palmitoyl CoA oxidase activity, cytochrome P450 concentration and lauric acid hydroxylase activity.
Statistics:
The significance of inter-group differences in haematology (excluding eosinophil, basophil and monocyte counts), blood chemistry and urinalysis (volume, specific gravity, pH and electrolytes only) were assessed by Student's t-test using a pooled error variance.
For organ weights and bodyweight gain, homogeneity of variance was tested using Bartlett’s test. Whenever this was found to be statistically significant a Behrens-Fisher test was used to perform pairwise comparisons, otherwise a Dunnett's test was used.
Inter-group differences in macroscopic pathology and histopathology were assessed using Fisher's Exact test.
For peroxisome proliferation parameters, homogeneity of variance was tested using Levene’s test.
Clinical signs:
effects observed, treatment-related
Description (incidence and severity):
From approximately week 3 of treatment, ungroomed coat, reddening of the skin around the anus and reddening of the back of the legs was observed for animals receiving DINP at 2500 mg/kg bw/day. Salivation was observed throughout the study for animals receiving clofibrate. This sign became apparent immediately after dosing but was absent 1 to 2 hours later. Emesis was also occasionally observed in these animals during the first two weeks of treatment.
Mortality:
no mortality observed
Description (incidence):
There were two deaths (one untreated female and one male given clofibrate) during Week 13 of treatment. Both of these deaths were incidental and were not related to treatment.
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
Body weight losses or low body weight gain were observed for two males and one female receiving 2500 mg/kg bw/day DINP when compared with the controls. With the exception of one male, low body weight gain or body weight losses were observed for all animals receiving clofibrate.
Food consumption and compound intake (if feeding study):
no effects observed
Description (incidence and severity):
Food consumption was unaffected for animals receiving DINP or clofibrate.
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
no effects observed
Description (incidence and severity):
No treatment related findings.
Haematological findings:
no effects observed
Description (incidence and severity):
Haematology investigations did not reveal any treatment-related findings for animals receiving DINP. Slightly low packed cell volumes, haemoglobin concentrations, erythrocyte counts and slightly high mean cell haemoglobin and mean cell volumes were observed for animals receiving clofibrate. Platelet counts were also slightly high for these females.
Clinical biochemistry findings:
no effects observed
Description (incidence and severity):
There were no blood chemistry changes.
Urinalysis findings:
no effects observed
Description (incidence and severity):
Urinary sodium and chloride levels were slightly low for females receiving clofibrate. There were no treatment-related changes in the urine of animals receiving DINP.
Behaviour (functional findings):
not examined
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
no effects observed
Description (incidence and severity):
There were no clear treatment-related organ weight changes for animals which received DINP. Slightly high absolute and body weight-relative kidney weights were noted for animals which received clofibrate. Absolute and body weight-relative salivary gland weights were also slightly high for females which received clofibrate.

Gross pathological findings:
effects observed, treatment-related
Description (incidence and severity):
Macroscopic examination at necropsy revealed a thin build for one male and one female which received 2500 mg/kg bw/day DINP. There were no other findings which were considered to be related to treatment with DINP or clofibrate.
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
no effects observed
Description (incidence and severity):
There were no microscopic findings which were considered to be related to treatment with DINP or clofibrate.
Histopathological findings: neoplastic:
not examined
Other effects:
no effects observed
Description (incidence and severity):
No changes in testosterone or oestradiol concentrations were observed, which were considered to be related to treatment with either DINP or clofibrate
Peroxisome proliferation:
Protein concentration of the 3000 x g supernatant subcellular fraction was not affected by DINP. Microsomal protein concentrations of male low and intermediate treatment groups showed a slight decrease after administration of DINP but these changes were not statistically significant at 5% level.
There was no evidence for a dose-related or statistically significant (at 5% level) effect of DINP on cyanide-insensitive palmitoyl CoA oxidase activity.
No statistically significant or treatment-related changes in cytochrome P450 concentration were seen following administration of DINP.
Changes observed in lauric acid hydroxylase activity were considered statistically not significant (at 5% level).

Key result
Dose descriptor:
NOEL
Effect level:
500 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
body weight and weight gain
clinical signs
gross pathology
Key result
Dose descriptor:
NOAEL
Effect level:
2 500 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: No significant toxicity found in the highest dose tested
Key result
Critical effects observed:
no
Conclusions:
In a 13-weeks repeated dose toxicity study with marmosets, the NOEL of DINP was considered to be 500 mg/kg/day.

Executive summary:

A 13-weeks repeated dose toxicity study in marmosets was performed following a method similar to OECD guideline 409 to assessed the systemic toxicity of di-isononyl phthalate (DINP), and also its potential for hepatic peroxisome proliferation. 3 groups of 4 males and 4 females were administered test material diluted in an emulsion of 1% methylcellulose plus 0.5% Tween by oral gavage at dosages of 100, 500 and 2500 mg/kg bw/day. Only vehicle as negative control and clofibrate administered at dosage of 500 mg/kg bw/d as positive control were tested concurrently. To assess the peroxisome proliferation in liver the following parameters were analysed: protein concentration, cyanide-insensitive palmitoyl CoA oxidase activity, cytochrome P450 concentration and lauric acid hydroxylase activity. Results for systemic toxicity showed only minor changes in some clinical signs, body weight gain and apparent thin build revealed at necropsy for one male and one female at 2500 mg/kg bw/day dose group. No statistically significant or treatment-related changes in any of the parameters analysed for peroxisome proliferation were seen following administration of DINP. There were no treatment-related histopathological changes. In conclusion, DINP did not produce any evidence of significant toxicity at 2500 mg/kg bw/day but based on minor changes found at this dosage level the NOEL was considered to be 500 mg/kg/day.

Endpoint:
sub-chronic toxicity: oral
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
documentation insufficient for assessment
Remarks:
The study predates GLP and the description of method is not provided
Principles of method if other than guideline:
- Principle of test: The study collects toxicity data relating to the phthalic acid esters used in food packaging. No data on test method. Data were obtained from FDA files.
GLP compliance:
no
Limit test:
no
Species:
dog
Strain:
not specified
Sex:
not specified
Route of administration:
oral: unspecified
Vehicle:
not specified
Analytical verification of doses or concentrations:
not specified
Duration of treatment / exposure:
13 weeks
Frequency of treatment:
Not specified
Control animals:
not specified
Key result
Dose descriptor:
NOEL
Effect level:
75 mg/kg bw/day (nominal)
Based on:
test mat.
Sex:
not specified
Basis for effect level:
other: Not specified
Critical effects observed:
not specified

The available information indicates that the levels of phthalates occurring in the diet from authorized uses do not pose any toxicological hazard. It is recognized that this statement is based in part on the premise that phthalates as a class are metabolized in a similar manner, thus allowing a general approach to the toxicity of these compounds.

Conclusions:
After 13 weeks of oral exposure, the NOEL of DIDP was equal to 75 mg/kg bw/day in dogs.


Executive summary:

The study collects toxicity data relating to the phthalic acid esters used in food packaging. The available information indicates that the levels of phthalates occurring in the diet from authorized uses do not pose any toxicological hazard. It is recognized that this statement is based in part on the premise that phthalates as a class are metabolized in a similar manner, thus allowing a general approach to the toxicity of these compounds. After 13 weeks of oral exposure, the NOEL of DIDP was equal to 75 mg/kg bw/day in dogs.

Endpoint:
sub-chronic toxicity: oral
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
documentation insufficient for assessment
Remarks:
The study predates GLP and the description of method is not provided
Principles of method if other than guideline:
- Principle of test: The study collects toxicity data relating to the phthalic acid esters used in food packaging. No data on test method. Data were obtained from FDA files.
GLP compliance:
no
Limit test:
no
Species:
rat
Strain:
not specified
Sex:
not specified
Route of administration:
oral: unspecified
Vehicle:
not specified
Analytical verification of doses or concentrations:
not specified
Duration of treatment / exposure:
13 weeks
Frequency of treatment:
Not specified
Control animals:
not specified
Key result
Dose descriptor:
NOEL
Effect level:
150 mg/kg bw/day (nominal)
Based on:
test mat.
Sex:
not specified
Basis for effect level:
other: Not specified
Critical effects observed:
not specified

The available information indicates that the levels of phthalates occurring in the diet from authorized uses do not pose any toxicological hazard. It is recognized that this statement is based in part on the premise that phthalates as a class are metabolized in a similar manner, thus allowing a general approach to the toxicity of these compounds.

Conclusions:
After 13 weeks of oral exposure, the NOEL of DIDP was equal to 150 mg/kg bw/day in rats.


Executive summary:

The study collects toxicity data relating to the phthalic acid esters used in food packaging. The available information indicates that the levels of phthalates occurring in the diet from authorized uses do not pose any toxicological hazard. It is recognized that this statement is based in part on the premise that phthalates as a class are metabolized in a similar manner, thus allowing a general approach to the toxicity of these compounds. After 13 weeks of oral exposure, the NOEL of DIDP was equal to 150 mg/kg bw/day in rats.

Endpoint:
chronic toxicity: oral
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 453 (Combined Chronic Toxicity / Carcinogenicity Studies)
GLP compliance:
not specified
Remarks:
This information was not reported
Limit test:
no
Species:
rat
Strain:
Fischer 344
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River Breeding Laboratory (Stoneridge, New York)
- Age at study initiation: 6 weeks old
- Weight at study initiation: 109 g (male) and 89 g (female)
- Fasting period before study: not specified
- Housing: individually except during the first week of acclimation. Cages: suspended stainless steel with indirect bedding
- Diet (e.g. ad libitum): ad libitum. Fresh diet presented weekly. Purina Certified Rodent Chow 5002
- Water (e.g. ad libitum): ad libitum. Automatic watering system
- Acclimation period: not specified.
Route of administration:
oral: feed
Vehicle:
unchanged (no vehicle)
Details on oral exposure:
- DIET PREPARATION
- Rate of preparation of diet (frequency): weekly
- Mixing appropriate amounts with (Type of food): DINP was added to Purina Certified Rodent Chow 5002 on a fixed weight percentage (w/w) basis and mixed thoroughly to ensure homogeneity. The stability of DINP in the test diets was demonstrated periodically.

Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
PRETREATMENT:
Extraction: Weighed aliquots of feed samples were extracted with n-hexanol
Filtration: extracted samples were filtered before analysis.

IDENTIFICATION AND QUANTIFICATION OF TEST SUBSTANCE/PRODUCT
- Separation method (e.g. HPLC, GC): Homogeneity and stability of test chemical in the diets were verified analytically by HPLC.
- Detection limits (LOD, LOQ) (indicate method of determination/calculation): The lower limit of detection, based on 2-g aliquots of feed, was 0.004 wt% DINP.
- Extraction recovery (indicate if results are corrected or not for recoveries): Analysis for uniformity of mixing was conducted on all test material containing batches prepared for use on Weeks 1, 2, 27, and 53 of the study and was determined to be within ±10% of the target concentration.
Duration of treatment / exposure:
24 months
Frequency of treatment:
daily
Dose / conc.:
0 other: %
Remarks:
nominal in diet
Dose / conc.:
0.03 other: %
Remarks:
Nominal in diet.
Equivalent to mean daily intake of 15 (male) and 18 (female) mg/kg bw/day
Dose / conc.:
0.3 other: %
Remarks:
Nominal in diet.
Equivalent to mean daily intake of 152 (male) and 184 (female) mg/kg bw/day
Dose / conc.:
0.6 other: %
Remarks:
Nominal in diet.
Equivalent to mean daily intake of 307 (male) and 375 (female) mg/kg bw/day
No. of animals per sex per dose:
110
Control animals:
yes, concurrent no treatment
Details on study design:
- Dose selection rationale: the high dose selected was limited to 0.6% DINP because higher doses of DINP might have jeopardized survival due to kidney lesions (Bucher et al., 1996; Ettlin et al., 1994). The mid dose of 0.3% was selected to produce lesser effects on the liver and kidney. The low dose o f 0.03% was selected as an anticipated NOEL based on 13-week data and pharmacokinetic considerations in F344 rats.
Positive control:
N/A
Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule for examinations: weekly on the same day of the week.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): yes
- Time schedule for examinations: weekly on the same day of the week.

FOOD EFFICIENCY: No

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No
OPHTHALMOSCOPIC EXAMINATION: No
HAEMATOLOGY: Yes
- Time schedule for collection of blood: at sacrified for animals scheduled for interim sacrifices and at termination for the rest of animals.
- Anaesthetic used for blood collection: Not specified
- Animals fasted: overnight fast (16 hr)
- How many animals: 10 rats/sex/group scheduled for interim sacrifices and on 20 rats/sex/group sacrificed at termination.
- Parameters examined: red blood count (RBC), hematocrit, hemoglobin, leukocyte count (total and differential), mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentrations, platelets, and reticulocyte count.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at sacrified for animals scheduled for interim sacrifices and at termination for the rest of animals.
- Anaesthetic used for blood collection: Not specified
- Animals fasted: overnight fast (16 hr)
- How many animals: 10 rats/sex/group scheduled for interim sacrifices and on 20 rats/sex/group sacrificed at termination.
- Parameters examined: albumin/globulin ratio, albumin, blood urea nitrogen, calcium, cholesterol, creatinine, electrolytes (Na +, K +, Cl-), globulin, glucose, serum glutamic oxaloacetic transaminase (SGOT or AST), serum glutamic pymvic transaminase (SGPT or ALT), serum osmolality, total bilirubin, total protein, and triglycerides.

URINALYSIS: Yes
- Time schedule for collection of urine: One week prior to each interim sacrifice and 2 weeks prior to terminal sacrifice, urine samples were collected during a 16-hr period for qualitative and quantitative analyses.
- Metabolism cages used for collection of urine: No data
- Animals fasted: No
- Parameters checked:
Quantitative analyses: urine volume, glucose, protein, creatinine, renal epithelial cell counts (REC), sodium, potassium, and osmolality.
Qualitative analyses: pH, specific gravity, ketones, bilirubin, and occult blood.

NEUROBEHAVIOURAL EXAMINATION: No
IMMUNOLOGY: No


Sacrifice and pathology:
GROSS PATHOLOGY: Yes
Preselected groups of 10 rats/sex/group were scheduled for interim sacrifice after 6, 12, and 18 months on study. The animals remaining on study were sacrificed at 24 months. Complete necropsies were performed on all animals.
Organ weighed: adrenals, brain, heart, kidney, liver, ovaries, spleen, testes, and thyroid/parathyroids.

HISTOPATHOLOGY: Yes
Tissues were preserved in 10% neutral buffered formalin and processed (paraffin technique) for light microscopic examination. Microscopic examination of hematoxylin- and eosin-stained sections was performed on tissues from all major organs in the high-dose and control groups plus gross lesions and target tissues (liver, kidney) from the mid- and low-dose groups.
All tissues were examined from animals that died or were sacrificed moribund during the study except when precluded by autolysis.
Tissues examined at study termination: adrenals, aorta, brain, epididymis, esophagus, eyes with optic nerve, femoral muscle with sciatic nerve, Harderian glands, heart, kidneys, large intestines (colon, cecum), liver, lungs (infused with fixative), mammary gland, mesenteric lymph nodes, ovaries, pancreas, pituitary, prostate, rectum, salivary glands, seminal vesicles, skin, small intestines (duodenum, jejunum, ileum), spinal cord (cervical, midthoracic, lumbar), spleen, sternum with marrow, stomach, testes, thyroid/parathyroids, trachea, urinary bladder, uterus, vagina, all gross lesions, and all tissue masses.
Tissues examined from the animals sacrificed at 6, 12, and 18 months: all gross lesions, all tissue masses, epididymides, kidneys, liver, lungs, ovaries, pituitary, spleen, testes, and thyroid.


Other examinations:
Morphological examination of liver: Livers of two rats/sex/dose group including controls were examined by electron microscopy for evidence of hepatic peroxisome induction at study termination. The evaluation was conducted using an identical protocol as that used in the 13-week dietary study on DINP in F344 rats (Bird et aL, 1987).
Statistics:
Bartlett's test of homogeneity of variance was used to determine if the groups had equivalent variances (Snedecor and Cochran, 1971). If the variances were equal, the testing for significance was done using a parametric method, a standard one-way ANOVA. If significant differences among the means were indicated, Dunnett's test was used (Dunnett, 1964) to determine which treatment groups differed from controls. If the groups did not have equivalent variances, the test of equality of means was performed using the Kruskall-Wallis test (Hollander and Wolfe, 1973). If the means were different, Dunn's summed rank test was used to determine which treatment groups differ significantly from control (Hollander and Wolfe, 1973). The test for equal variance was conducted at the 1% level of significance. All other tests were conducted at the 5 and 1% levels of significance.
The survival analysis used two methods: (1) the Weibull estimate of median survival and (2) the Kaplan-Meier method with a comparison between groups using both the generalized Kruskal-Wallis test and Cox's test (Kaplan and Meier, 1958).
Three methods of statistical analyses were used to assess tumor incidence data in the chronic study: (1) life table analyses (Mantel and Haenszel, 1959; Cox, 1972; Tarone, 1975), (2) incidental tumor analysis (Haseman, 1984), and (3) unadjusted analysis for linear dose response. The last method consists of a pairwise comparison of each dose group with the control by the Fisher exact test and a test for linear trend (Armitage, 1971; Gartet al., 1979).
Clinical signs:
no effects observed
Description (incidence and severity):
The incidence of clinical in-life observations was relatively low throughout the 24-month test period. The most frequently noted observation included alopecia and scabs on the skin which appeared unrelated to treatment.
Mortality:
mortality observed, treatment-related
Description (incidence):
A slight decrease in overall survival was noted in the mid- and high-dose groups of both sexes compared to controls, but whether or not this decrease was statistically significant depended on the statistical method employed. No difference was observed using the Weibull technique. The Cox and generalized Kruskall-Wallis tests indicated a significant difference in survival in mid- and high-dose female rats.
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
When compared with controls, the high-dose males had a statistically significant, dose-related decrease (4-7%) in body weight at 12, 18 and 24 months of treatment. There were no statistically significant changes in females.
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Description (incidence and severity):
Compared to the controls, slight decreases were observed.
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
not examined
Haematological findings:
effects observed, treatment-related
Description (incidence and severity):
In general, the mean hematologic values were within normal limits for both sexes treated with DINP for 6, 12, and 18 months. At study termination, the red blood cell count and haemoglobin and hematocrit mean values were slightly lower for mid- and high-dose males and females compared to control values. However, only the high-dose males showed a statistically significant decrease in RBC, hemoglobin, and hematocrit compared with controls. The high-dose males and females also exhibited an increased frequency of occurrence of nucleated RBC, polychromatophilic red cells, and reticulocytes when compared with control animals.
Clinical biochemistry findings:
effects observed, treatment-related
Description (incidence and severity):
An evaluation of the serum chemistry values at 6, 12, and 18 months revealed no remarkable findings. Some parameters were statistically increased (BUN, A/G ratio, creatinine) but were judged unlikely to be of biological significance due to a lack of dose response.
The following parameters usually associated with liver function were weakly increased in the mid- and high-dose males at all time intervals in the study: alkaline phosphatase, SGOT, and SGPT. In general, these responses were statistically significant and may be related to treatment. No statistically significant effects were observed on total bilirubin.
The results of the female serum chemistry profile revealed no statistically significant treatment-related effects on liver function parameters.
Urinalysis findings:
effects observed, treatment-related
Description (incidence and severity):
The qualitative urine chemistry parameters were non remarkable at all time intervals for both males and females.
The quantitative urine chemistry parameters were unaffected in females at all time intervals, but the males showed slight but statistically significant changes in some of the parameters throughout the study. The high-dose males exhibited increased urine volumes when compared to controls at all time intervals. In the mid- or high-dose males, potassium and glucose showed a statistically significant increase at 6, 12, and 18 months, but not at 24 months. A statistically significant increase in excretion of renal epithelial cells was noted in high-dose males at 6 months but not at later treatment periods.
Behaviour (functional findings):
not examined
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
effects observed, treatment-related
Description (incidence and severity):
Both males and females of the mid- and high dose groups had a statistically significant, dose-related increase in relative kidney and liver weights throughout most of the treatment period; the absolute liver and kidney weights demonstrated a similar trend. At study termination, the mid- and high-dose males and high-dose females exhibited a statistically significant increase in absolute and relative spleen weight compared to controls. Absolute and relative adrenal weights were slightly but significantly increased in high-dose female rats after 6 and 12 months of treatment. In addition, at study termination, relative but not absolute adrenal weights were slightly but significantly increased in high-dose rats of both sexes. No treatment-related changes were observed in the absolute or relative organ weights for ovaries, testes, brain, heart, or thyroid/parathyroid.

Gross pathological findings:
effects observed, treatment-related
Description (incidence and severity):
No grossly observable and treatment-related abnormalities were apparent at each of the interim sacrifices. At study termination, however, the mid- and high-dose males and high-dose females exhibited an increased incidence of splenic enlargement when compared with control animals.
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Description (incidence and severity):
No treatment-related effects on tissues were observed in rats sacrificed after 6 and 12 months of treatment.
At the 18-month sacrifice nonneoplastic lesions were observed in the liver and kidney of treated rats. Minimal to slight centrilobular to midzonaI hepatocellular enlargement was present in 9/10 male and 10/10 female rats treated with 0.6% DINP; this effect was absent in controls. In the kidneys, a minimal increase in tubular cell pigment was noted in the tubular epithelium of high dose male rats.
At terminal sacrifice, a variety of spontaneous disease lesions and incidental findings of the expected type and incidence occurred in control and treated rats without relationship to treatment with the exception of liver lesions and mononuclear cell leukemia (MNCL). Slight centrilobular to midzonal hepatocellular enlargement was present in a small number of rats and was comparable to the findings at the 18-month sacrifice.
DINP failed to produce any treatment-related effects on the testes.
Histopathological findings: neoplastic:
effects observed, treatment-related
Description (incidence and severity):
No treatment-related effects on tissues were observed in rats sacrificed after 6, 12 and 18 months of treatment.
The most common causes of the unscheduled deaths and/or morbidity were mononuclear cell leukemia (MNCL) and, to a lesser extent, pituitary neoplasia. Tubular cell pigmentation in the kidney was increased in severity in animals with advanced MNCL.
MNCL occurred at a statistically significant increased incidence in the mid- and high-dose groups of both sexes when compared with the control groups and with a significantly increasing trend over time.
The MNCL was associated with a variety of hepatic alterations (nonneoplastic lesions) which included regenerative nodules, focal necrosis, spongiosis hepatis, and "hepatopathy associated with leukemia".
DINP produced no treatment-related preneoplastic or neoplastic lesions of the liver.
Transitional cell carcinoma and tubular cell carcinoma were found in 3 mid-dose and 2 high-dose male rats respectively, although they were not was not statistically significant when compared to control animals.
There was no evidence of any treatment-related preneoplastic renal lesions.
DINP also failed to produce any treatment-related effects on the testes. As expected, the control animals displayed a high incidence of testicular tumors.
Other effects:
no effects observed
Description (incidence and severity):
Morphological Examination of Liver: Ultrastructural examination of liver specimens from representative rats of each sex from the four groups did not reveal any treatment-related peroxisomal proliferation.

Key result
Dose descriptor:
NOEL
Effect level:
0.03 other: % diet
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: Biological effects found in the mid-dose group
Remarks on result:
other: Equivalent to ca. 17 mg/kg bw/day
Key result
Critical effects observed:
no

Table 1: Body Weights (g) for F344 Rats in a Chronic DINP Study (Mean ± SD)

Dietary concentration of DINP

(wt %)

Sex

Month

Nº examined

per dose

0

0.03

0.3

0.6

Male

Pretest

110

109±5

109±5

109±5

109±5

6

110

329±22

332±23

330±20

324±23

12

100

386±23

385±21

380±22

371±25a

18

78-83

404±24

406±24

401±19a

388±23a

24

46-56

391±21

379±32

377±29a

364±27a

Female

Pretest

110

89±3

89±3

89±3

89±3

6

110

188±11

190±10

192±10

190±10

12

99-100

223±15

226±15

228±16

223±19

18

76-83

266±22

269±19

272±21

263±19

24

44-63

281±27

283±18

292±23a

280±21

a Statistically significant from control group mean at 5% level.

Table 2. Survival for F344 Rats in a Chronic DINP Study at Terminal Sacrifice

DINP dose

groups (wt %)

No. in group

No. of

unscheduled deaths

No. of survivors at terminal sacrifice

Percentage survivors

Males

 

 

 

 

0

81

20

61

75

0.03

80

25

55

69

0.3

80

30

50

62

0.6

80

29

51

64

Females

 

 

 

 

0

81

16

65

80

0.03

81

24

57

70

0.3

80

31

49

61a

0.6

80

26

54

68b

a Statistically significant from control group at 1% level based on Kruskall-Wallis test and Cox's test, but not statistically significant by the Weibull technique.

b Statistically significant from control group at 5% level based on Kruskall-Wallis test and Cox's test.

Table 3. Organ Weights as a Percentage of Body Weight for Male F344 Rats in a 2-Year DINP Study (Mean ± SD)

Dietary concentration of DINP (wt %)

Observation

Month

(N)

0

0.03

0.3

0.6

Liver

6

10

2.4±0.1

2.5±0.1

2.8±0.1a

3.1±0.2"

12

10

2.6±0.1

2.6±0.1

2.9±0.1a

3.1±0.1a

18

10

2.7±0.3

2.7±0.1

3.1±0.5

3.1±0.2b

24

50-61

3.2±0.6

3.4±0.8

3.8±0.8a

4.2±0.8a

Kidney

6

10

0.66±0.03

0.67±0.03

0.71±0.02a

0.75±0.036a

12

10

0.64±0.03

0.65±0.02

0.70±0.03a

0.73±0.03a

18

10

0.72±0.07

0.69±0.03

0.76±0.05

0.78±0.04b

24

50-61

0.81±0.10

0.87±0.12

0.89±0.10a

0.97±0.14a

Spleen

6

9-10

0.19±0.01

0.19±0.01

0.19±0.01

0.20±0.01

12

10

0.18±0.02

0.17±0.01

0.18±0.01

0.19±0.02

18

9-10

0.23±0.06

0.22±0.02

0.35±0.34

0.25±0.04

24

50-61

0.46±0.37

0.54±0.76

0.74±0.87a

0.74±0.76a

a Statistically significant from control group mean at 1% level.

b Statistically significant from control group mean at 5% level.

Table 4. Organ Weights as a Percentage of Body Weight for Female F344 Rats in a 2-Year DINP Study (Mean ± SD)

Dietary concentration of DINP (wt %)

Observation

Month

(N)

0

0.03

0.3

0.6

Liver

6

10

2.6±0.1

2.7±0.2

2.9±0.1a

3.3±0.1a

12

10

2.6±0.1

2.6±0.1

2.9±0.1a

3.3±0.1a

18

9-10

2.6±0.1

2.5±0.2

2.9±0.3

3.3±0.4a

24

48-65

3.1±0.5

3.2±0.7

3.6±0.8a

4.0±0.7a

Kidney

6

10

0.77±0.03

0.76±0.03

0.80±0.03

0.86±0.04a

12

10

0.71±0.05

0.72±0.04

0.78±0.04a

0.81±0.03a

18

9-10

0.70±0.04

0.69±0.03

0.77±0.07b

0.76±0.05b

24

48-65

0.81±0.13

0.80±0.09

0.87±0.15a

0.89±0.10a

Spleen

6

10

0.25±0.02

0.26±0.02

0.25±0.02

0.25±0.01

12

10

0.21±0.01

0.21±0.02

0.21±0.02

0.23±0.03

18

9-10

0.22±0.04

0.24±0.18

0.28±0.17

0.23±0.06

24

48-65

0.42±0.70

0.54±1.02

0.44±0.67

0.66±0.99b

a Statistically significant from control group mean at 1% level.

b Statistically significant from control group mean at 5% level.

Table 5. Hematologic Values of F344 Rats Fed 2 Years at Dietary Concentrations of DINP (Mean ± SD)

Dietary concentration of DINP (wt %)

Sex

Hematology parameter a

0

0.03

0.3

0.6

Male

White blood cell (x 103/mm3)

5.1±1.2

4.8±1.9

21.7±58.6

32.7±64.8

Red blood cell (x 106/mm3)

7.4±0.9

7.4±1.5

7.2±1.8

6.4±1.7b

Hemoglobin (g%)

16.3±1.8

15.3±3.2

15.0±3.1

13.2±2.9c

Hematocrit (%)

47.0±5.6

44.7±9.8

43.2±8.7

38.2±8.0c

MCV

60±2

61±6

61±5

61±8

Female

White blood cell (x 103/mm3)

3.1±0.9

4.6±4.1

5.0±3.2b

8.4±17.2

Red blood cell (x 106/mm3)

7.3±0.8

7.0±1.8

6.3±1.6

6.3±2.0

Hemoglobin (g%)

16.3±1.7

15.5±3.5

13.9±3.5

14.1±3.7

Hematocrit (%)

46.1±4.7

43.8±10.4

39.6±10.0

40.1±11.0

MCV

63±2

64±5

63±5

65±7

a Nineteen to 20 rats were examined at each concentration.

b Statistically significant from control group mean at 5% level.

c Statistically significant from control group mean at 1% level.

Table 6. Selected Serum Chemistry Values for Rats in a Chronic DINP Study (Mean ± SD)

Dietary concentration of DINP (wt %)

Serum chemistry parameter

Month a, b

Sex

0

0.03

0.3

0.6

AST (IU/liter)

6

M

68±8

71±15

102±32c

137±95c

12

M

102±17

101±22

145±36c

185±86c

18

M

69±7

68±12

113±76

146±105c

24

M

92±42

93±72

112±58

206±220

24

F

83±35

120±147

110±90

185±249

ALT (IU/liter)

6

M

37±8

38±7

81±52

128±145c

12

M

71±13

70±21

103±56

158±101

18

M

42±10

39±7

69±39

128±126c

24

M

42±10

45±23

89±76d

74±68

24

F

55±23

59±46

71±53

135±154

Alkaline phosphatase (IU/liter)

6

M

56±10

54±6

59±6

72±16d

12

M

49±9

51±13

54±13

70±19

18

M

49±6

41±6

65±48

63±18

24

M

41±14

47±38

65±47c

116±132d

24

F

47±20

65±85

73±53

78±63

a Group size at 6, 12, and 18 months was 9-10 rats examined for each parameter.

b Group size at 24 months was 20 rats examined for each parameter.

c Statistically significant from control group mean at 5% level.

d Statistically significant from control group mean at 1% level.

Table 7. Incidence of Nonneoplastic Liver Lesions in Rats Fed DINP for 2 Years

Dietary concentration of DINP (wt %)

0

0.03

0.3

0.6

0

0.03

0.3

0.6

Sex

Males

Females

Number examined

81

80

80

80

81

81

80

80

Liver

 

 

 

 

 

 

 

 

  Focal necrosis

10

9

16

26

13

11

19

21

  Spongiosis hepatis

24

24

51

62

4

1

3

4

  Sinusoid ectasia

16

16

24

33

9

4

6

10

  Hepatopathy associated with leukemia

22

17

34

33

16

18

24

33

  Hepatocellular enlargement

1

1

1

9

1

0

0

11

  Foci of vacuolated hepatocytes

15

14

1

0

17

16

8

5

  Diffuse fatty changes

12

4

4

0

10

9

3

3

  Cholangiectasis

52

25

16

20

10

6

3

5

  Regenerative nodules

3

3

6

6

5

7

10

9

Table 8. Incidence of selected Neoplastic and Preneoplastic Lesions in Rats fed DINP for 2 years

Dietary concentration of DINP (wt %)

0

0.03

0.3

0.6

0

0.03

0.3

0.6

Sex

Males

Females

Number examined

81

80

80

80

81

81

80

80

           Liver

 

 

 

 

 

 

 

 

Neoplastic nodules (1)

3

1

1

1

0

2

0

1

Hepatocellular cancer (2)

0

0

0

3

1

0

0

1

Combined (1 and 2)

3

1

1

4

1

2

0

2

Basophilic foci

53

62

48

42

72

64

64

54

Eosinophilic foci

58

50

45

51

59

45

42

32

             Kidney

 

 

 

 

 

 

 

 

Transitional cell carcinoma

0

0

3

0

0

0

0

0

Transitional cell adenoma

0

0

0

0

0

0

0

0

Tubular cell carcinoma

0

1

0

2

0

0

0

0

Tubular cell adenoma

0

0

 

0

0

0

0

0

Hyperplasia of transitional cell epithelium

21

23

31

25

32

39

34

32

Testes:  Bilateral interstitial cell tumours

71

64

70

72

-

-

-

-

Hematopoietic system:
Mononuclear cell leukemia

33

28

48a

51a,c

22

20

30c

43a,b,c

a Statistically significant from control group at 5% level using the Fisher exact test.

b Statistically significant from control group at 5% level using the incidental tumor test.

c Statistically significant from control group at 5% level using the life table test.

Conclusions:
In a 2-year chronic toxicity study with rats, the NOEL of DINP was found to be 0.03 wt% or approximately 17 mg/kg/day.




Executive summary:

A 2-year repeated dose toxicity study (diet route) was performed on diisononyl phthalate (DINP) according to a method similar to OECD guideline 453. Groups of 110 Fischer 344 rats/sex were fed test substance at dietary levels of 0, 0.03, 0.3, and 0.6 wt% for periods up to 2 years. Interim sacrifices of 10 predesignated rats/sex/dose were at 6, 12, and 18 months with surviving animals sacrificed at 24 months. At study termination, survival was higher than 60% for every group. At the mid or high dose, the following biological effects were noted: slight decreases in food consumption and body weight; slight increase in mortality; a dose-related increase in relative organ weights of liver and kidney; and some slight effects on urinalysis, hematologic, and clinical chemistry parameters. No peroxisome induction was observed in livers of treated rats compared with controls. No clear treatment-related nonneoplastic or neoplastic lesions were found. However, mononuclear cell leukemia (MNCL) and changes known to be associated with an increased incidence of MNCL were seen in the mid-dose and high dose groups. Published literature suggests that MNCL is a common finding in aging F344 rats and that this increased incidence in rats treated with DINP is not relevant to man. A clear NOEL was demonstrated for all biological end points at a dietary level of 0.03 wt% or approximately 17 mg/kg/day of DINP.

Endpoint:
sub-chronic toxicity: oral
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
The target substance (DUP) belongs to the OECD HPV category High Molecular Weight Phthalate Ester (HMWPE) which consists of esters with an alkyl carbon backbone with 7 carbon (C) atoms or greater. The source substance (DINP) although is not formally part of this category as it was assessed previously, it satisfies the category definition as its backbone length is C7 or above and also produces similar effects of developmental or reproductive toxicity. Thus, these substances share the same functional groups and also have comparable environmental and toxicological properties.
See attached the reporting format.
Reason / purpose for cross-reference:
read-across source
Key result
Dose descriptor:
NOEL
Effect level:
567.02 mg/kg bw/day (actual dose received)
Based on:
other: Read across from an analogue
Sex:
male/female
Basis for effect level:
other: Read-across from an analogue for which clinical signs, body weight or gross pathology effects were found in the highest dose tested (2500 mg/kg bw/day)
Remarks on result:
other: read-across from an analogue for which NOEL = 500 mg/kg bw/day (actual dose received)
Key result
Dose descriptor:
NOAEL
Effect level:
2 835.1 mg/kg bw/day (actual dose received)
Based on:
other: Read across from an analogue
Sex:
male/female
Basis for effect level:
other: Read-across from an analogue for which no significant toxicity was found in the highest dose tested
Remarks on result:
other: read-across from an analogue for which NOAEL = 2500 mg/kg bw/day (actual dose received)
Key result
Critical effects observed:
no
Conclusions:
Based on the read-across approach from the analogue DINP assessed in a 13-weeks repeated dose toxicity study with marmosets, the NOEL of DUP was calculated to be 567.02 mg/kg/day.

Executive summary:

A 13-weeks repeated dose toxicity study in marmosets was performed following a method similar to OECD guideline 409 to assessed the systemic toxicity of di-isononyl phthalate (DINP), and also its potential for hepatic peroxisome proliferation. 3 groups of 4 males and 4 females were administered test material diluted in an emulsion of 1% methylcellulose plus 0.5% Tween by oral gavage at dosages of 100, 500 and 2500 mg/kg bw/day. Only vehicle as negative control and clofibrate administered at dosage of 500 mg/kg bw/d as positive control were tested concurrently. To assess the peroxisome proliferation in liver the following parameters were analysed: protein concentration, cyanide-insensitive palmitoyl CoA oxidase activity, cytochrome P450 concentration and lauric acid hydroxylase activity. Results for systemic toxicity showed only minor changes in some clinical signs, body weight gain and apparent thin build revealed at necropsy for one male and one female at 2500 mg/kg bw/day dose group. No statistically significant or treatment-related changes in any of the parameters analysed for peroxisome proliferation were seen following administration of DINP. There were no treatment-related histopathological changes. In conclusion, DINP did not produce any evidence of significant toxicity at 2500 mg/kg bw/day but based on minor changes found at this dosage level the NOEL was considered to be 500 mg/kg/day. Based on these results, the read-across

approach was applied and the NOAEL for diundecyl phthalate (DUP) was calculated to be 2835.10 mg/kg/day and the NOEL was calculated to be 567.02 mg/kg/day.

Endpoint:
sub-chronic toxicity: oral
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
EPORTING FORMAT FOR THE ANALOGUE APPROACH
The target substance (DUP) belongs to the OECD HPV category High Molecular Weight Phthalate Ester (HMWPE) which consists of esters with an alkyl carbon backbone with 7 carbon (C) atoms or greater. The source substance (DIDP) although is not formally part of this category as it was assessed previously, it satisfies the category definition as its backbone length is C7 or above and also produces similar effects of developmental or reproductive toxicity. Thus, these substances share the same functional groups and also have comparable environmental and toxicological properties.
See attached the reporting format.
Reason / purpose for cross-reference:
read-across source
Key result
Dose descriptor:
NOEL
Effect level:
79.71 mg/kg bw/day (nominal)
Based on:
other: Read across from an analogue
Sex:
not specified
Basis for effect level:
other: Not specified
Remarks on result:
other: read-across from an analogue for which NOEL = 75 mg/kg bw/day (nominal)
Critical effects observed:
not specified

The available information indicates that the levels of phthalates occurring in the diet from authorized uses do not pose any toxicological hazard. It is recognized that this statement is based in part on the premise that phthalates as a class are metabolized in a similar manner, thus allowing a general approach to the toxicity of these compounds.

Conclusions:
Based on the read-across approach from the analogue DIDP assessed in a 13-weeks repeated dose toxicity study with dogs, the NOEL of DUP was calculated to be 79.71 mg/kg bw/day in dogs.


Executive summary:

The study collects toxicity data relating to the phthalic acid esters used in food packaging. The available information indicates that the levels of phthalates occurring in the diet from authorized uses do not pose any toxicological hazard. It is recognized that this statement is based in part on the premise that phthalates as a class are metabolized in a similar manner, thus allowing a general approach to the toxicity of these compounds. After 13 weeks of oral exposure, the NOEL of DIDP was equal to 75 mg/kg bw/day in dogs. Based on these results, the read-across approach was applied and the NOEL for diundecyl phthalate (DUP) was calculated to be 79.71 mg/kg/day.

Endpoint:
sub-chronic toxicity: oral
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
The target substance (DUP) belongs to the OECD HPV category High Molecular Weight Phthalate Ester (HMWPE) which consists of esters with an alkyl carbon backbone with 7 carbon (C) atoms or greater. The source substance (DIDP) although is not formally part of this category as it was assessed previously, it satisfies the category definition as its backbone length is C7 or above and also produces similar effects of developmental or reproductive toxicity. Thus, these substances share the same functional groups and also have comparable environmental and toxicological properties.
See attached the reporting format.
Reason / purpose for cross-reference:
read-across source
Key result
Dose descriptor:
NOEL
Effect level:
159.42 mg/kg bw/day (nominal)
Based on:
other: Read across from an analogue
Sex:
not specified
Basis for effect level:
other: Not specified
Remarks on result:
other: read-across from an analogue for which NOEL = 150 mg/kg bw/day (nominal)
Critical effects observed:
not specified

The available information indicates that the levels of phthalates occurring in the diet from authorized uses do not pose any toxicological hazard. It is recognized that this statement is based in part on the premise that phthalates as a class are metabolized in a similar manner, thus allowing a general approach to the toxicity of these compounds.

Conclusions:
Based on the read-across approach from the analogue DIDP assessed in a 13-weeks repeated dose toxicity study with rats, the NOEL of DUP was determined to be 159.42 mg/kg bw/day in rats.


Executive summary:

The study collects toxicity data relating to the phthalic acid esters used in food packaging. The available information indicates that the levels of phthalates occurring in the diet from authorized uses do not pose any toxicological hazard. It is recognized that this statement is based in part on the premise that phthalates as a class are metabolized in a similar manner, thus allowing a general approach to the toxicity of these compounds. After 13 weeks of oral exposure, the NOEL of DIDP was equal to 150 mg/kg bw/day in rats. Based on these results, the read-across approach was applied and the NOEL for diundecyl phthalate (DUP) was calculated to be 159.42 mg/kg/day.

Endpoint:
chronic toxicity: oral
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
The target substance (DUP) belongs to the OECD HPV category High Molecular Weight Phthalate Ester (HMWPE) which consists of esters with an alkyl carbon backbone with 7 carbon (C) atoms or greater. The source substance (DINP) although is not formally part of this category as it was assessed previously, it satisfies the category definition as its backbone length is C7 or above and also produces similar effects of developmental or reproductive toxicity. Thus, these substances share the same functional groups and also have comparable environmental and toxicological properties.
See attached the reporting format.
Reason / purpose for cross-reference:
read-across source
Key result
Dose descriptor:
NOEL
Effect level:
19.28 mg/kg bw/day (actual dose received)
Based on:
other: Read across from an analogue
Sex:
male/female
Basis for effect level:
other: Read-across from an analogue for which biological effects were found in the mid-dose group
Remarks on result:
other: read-across from an analogue for which NOEL = 0.03% in diet (Equivalent to ca. 17 mg/kg bw/day)
Key result
Critical effects observed:
no
Conclusions:
Based on the read-across approach from the analogue DINP assessed in a 2-year chronic toxicity study with rats, the NOEL of DUP was determined to be 19.28 mg/kg/day.




Executive summary:

A 2-year repeated dose toxicity study (diet route) was performed on diisononyl phthalate (DINP) according to a method similar to OECD guideline 453. Groups of 110 Fischer 344 rats/sex were fed test substance at dietary levels of 0, 0.03, 0.3, and 0.6 wt% for periods up to 2 years. Interim sacrifices of 10 predesignated rats/sex/dose were at 6, 12, and 18 months with surviving animals sacrificed at 24 months. At study termination, survival was higher than 60% for every group. At the mid or high dose, the following biological effects were noted: slight decreases in food consumption and body weight; slight increase in mortality; a dose-related increase in relative organ weights of liver and kidney; and some slight effects on urinalysis, hematologic, and clinical chemistry parameters. No peroxisome induction was observed in livers of treated rats compared with controls. No clear treatment-related nonneoplastic or neoplastic lesions were found. However, mononuclear cell leukemia (MNCL) and changes known to be associated with an increased incidence of MNCL were seen in the mid-dose and high dose groups. Published literature suggests that MNCL is a common finding in aging F344 rats and that this increased incidence in rats treated with DINP is not relevant to man. A clear NOEL was demonstrated for all biological end points at a dietary level of 0.03 wt% or approximately 17 mg/kg/day of DINP. Based on these results, the read-across approach was applied and the NOEL for diundecyl phthalate (DUP) was determined to be 19.28 mg/kg bw/day in rats.

Endpoint:
short-term repeated dose toxicity: oral
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)
GLP compliance:
not specified
Remarks:
This information was not reported
Limit test:
yes
Species:
rat
Strain:
Sprague-Dawley
Sex:
male
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories (Japan)
- Females (if applicable) nulliparous and non-pregnant: N/A
- Age at study initiation: 5-6 weeks
- Weight at study initiation: ca. 155 g
- Fasting period before study: not specified
- Housing: housed under specificpathogen-free (SPF) conditions. Animals were housed in clear polycarbonate cages with wood chips for bedding.
- Diet (e.g. ad libitum): pellet rodent diet available ad libitum
- Water (e.g. ad libitum): available ad libitum
- Acclimation period: 1 week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 23 ± 3ºC
- Humidity (%): 55 ± 5%
- Air changes (per hr): ≥ 15 cycles per hour
- Photoperiod (hrs dark / hrs light): 12 hours/day
Route of administration:
oral: gavage
Vehicle:
corn oil
Analytical verification of doses or concentrations:
not specified
Duration of treatment / exposure:
4 weeks
Frequency of treatment:
daily
Dose / conc.:
500 mg/kg bw/day (actual dose received)
No. of animals per sex per dose:
6 males
Control animals:
yes, concurrent vehicle
Details on study design:
- Dose selection rationale: random based on body weight
Positive control:
N/A
Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: daily
BODY WEIGHT: Yes
- Time schedule for examinations: days 0, 3, 6, 9, 12, 15, 18, 21, 24, and 28

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal measured at the beginning of the treatment and twice a week during the four week exposure.

HAEMATOLOGY: Yes
- Time schedule for collection of blood: during autopsy.
- Anaesthetic used for blood collection: N/A
- Animals fasted: Not specified
- How many animals: all animals
- Parameters examined: red blood cell (RBC) count, hemoglobin (Hb) concentration, hematocrit (Ht), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), platelet (PLT) count, and white blood cell (WBC) count.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: during autopsy
- Animals fasted: Not specified
- How many animals: all animals
- Parameters examined: serum biochemistry parameters including calcium, potassium, sodium, albumin, blood urea nitrogen (BUN), cholesterol, triglyceride (TG), creatinine, glucose, total cholesterol, total bilirubin, total protein, alkaline phosphatase (ALP), glutamate pyruvate (GPT), glutamate oxaloacetate transaminase (GOT) and g-gluamyl transferase (GGT).

URINALYSIS: Yes
– Time schedule for collection of urine: 12 hours prior to necropsy
- Metabolism cages used for collection of urine: No data. Urine collection cages used.
- Animals fasted: Yes, during collection period
- Parameters examined: occult blood, pH, protein, urobilinogen, glucose, nitrite, bilirubin, ketone bodies, leukocytes, and urine specific gravity.

Sacrifice and pathology:
GROSS PATHOLOGY: Yes; Under anesthesia, the heart, lung, liver, kidneys, adrenal glands, spleen, thymus, thyroid glands, testes, and epididymides were weighed, and organ to body weight ratios were calculated.

HISTOPATHOLOGY: No

Other examinations:
SPERM COUNT AND MOTILITY ANALYSIS:
The right cauda epididymis from each of the animals in the 4-wk treated group was used for the sperm count analysis, and the left cauda epididymis was used for the motility analysis.
Data from sperm count analysis were expressed as the number of sperm per gram cauda epididymal tissue.
The sperm motion parameters included the percentage of motile sperm, the average path velocity (VAP), straight-line velocity (VSL), curvilinear velocity (VCL), the amplitude of the lateral head displacement (ALH), the beat cross frequency (BCF), straightness (STR), and linearity (LIN).
Statistics:
The quantitative differences between control and treatment group in terms of the body and organ weights, sperm counts and motility, blood hematology, serum biochemistry, and urine parameters were examined by one-way analysis of variance (ANOVA). Dunnett’s test (p < 0.05) was applied for pairwise comparison of the control and treatment group.
Clinical signs:
no effects observed
Description (incidence and severity):
Salivation was observed immediately after administration in all animals.
No other clinical sign was observed.
Mortality:
no mortality observed
Description (incidence):
No deaths occurred during the study.
Body weight and weight changes:
no effects observed
Description (incidence and severity):
There were no significant differences in body weight gain between treatment group and control throughout the study.
Food consumption and compound intake (if feeding study):
no effects observed
Description (incidence and severity):
There were no significant differences in food consumption between treatment group and control throughout the study.
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
not examined
Haematological findings:
no effects observed
Description (incidence and severity):
There were no statistically significant differences in any haematological parameter examined between treatment and control group. All the values were within the normal range.
Clinical biochemistry findings:
effects observed, treatment-related
Description (incidence and severity):
GLU, GOT and ALP levels in the treatment group were significantly higher than in the control group.
Urinalysis findings:
no effects observed
Description (incidence and severity):
There were no significant differences in the urine parameters examined between treatment and control group.
Behaviour (functional findings):
not specified
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
no effects observed
Description (incidence and severity):
There were no significant differences in the relative organ weights between treatment and control group.

Gross pathological findings:
no effects observed
Neuropathological findings:
not examined
Histopathological findings: non-neoplastic:
not examined
Histopathological findings: neoplastic:
not examined
Other effects:
effects observed, treatment-related
Description (incidence and severity):
SPERM COUNT AND MOTILITY ANALYSIS
The mean sperm count in the treated group was significant lower compared to the control (72.1%). In addition, the mean percent sperm motility in the treated group (27.50%) was also significantly lower than in the control (74.67%).

Key result
Dose descriptor:
LOAEL
Effect level:
500 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male
Basis for effect level:
other: Sperm count and sperm motility
Key result
Critical effects observed:
no
Lowest effective dose / conc.:
500 mg/kg bw/day (actual dose received)
System:
male reproductive system
Organ:
cauda epididymis

Table 1. Relative Organ Weight of Sprague-Dawley (SD) Rats Orally Treated With DUP for 4 wk

Phthalate
ester

Thymus

Heart

Liver

Spleen

Kidney
(paired)

Adrenal
(paired)

Testis
(paired)

Epididymis
(left)

CON a

0.12 ± 0.03

0.36 ± 0.03

2.45 ± 0.13

0.23 ± 0.05

0.34 ± 0.01

0.012 ± 0.002

0.771 ± 0.046

0.161 ± 0.011

DUP

0.11 ± 0.07

0.43 ± 0.08

2.97 ± 0.33

0.21 ± 0.02

0.37 ± 0.04

0.013 ± 0.003

0.669 ± 0.043

0.161 ± 0.028

Note. Data are mean±SD (n = 6 animals). Asterisk indicates significantly different from the control group at p < .05.

a Treated with corn oil.

Table 2. Hematological Values of SD rats Orally Treated With DUP for 4 wk

Phthalate
ester

WBC (103/mm3)

RBC (106/ mm3)

Hb (g/dl)

Ht (%)

MCV (μm3)

MCH (pg)

MCHC (g/dl)

PLT (103/ mm3)

CON a

7.40 ± 0.95

8.46 ± 0.19

16.80 ± 0.62

51.80 ± 1.93

61.25 ± 1.21

19.87 ± 0.37

32.45 ± 0.59

870.50 ± 247.03

DUP

9.25 ± 0.91

8.67 ± 0.46

16.70 ± 0.62

51.47 ± 1.68

59.45 ± 1.68

19.30 ± 0.57

32.45 ± 0.58

990.50 ± 145.07

Note. Data are mean ± SD (n = 6 animals). Asterisk indicates significantly different from the control group at p < .05.

a Treated with corn oil.

Table 3. Biochemical Serum Values Following DUP Treatment

Phthalate
ester

GLU (g/dl)

T.P (g/dl)

ALB (g/dl)

T.BIL (mg/
dl)

GOT (IU/L)

GPT (IU/L)

ALP (IU/L)

T.CHO (mg/dl)

HDL.C
(mg/dl)

GGT
(IU/L)

TG (mg/dl)

CA (mg/dl)

BUN
(mg/dl)

CONa

123.0 ± 20.05

7.03 ± 0.28

2.5 ± 0.09

0.1 ± 0.00

75.67 ± 7.81

41.17 ± 7.03

347.0 ± 49.78

93.5 ± 11.04

27.33 ± 2.16

0.83 ± 0.02

42.17 ± 7.65

10.2 ± 0.43

17.12 ± 1.41

DUP

134.0 ± 18.11

7.67 ± 0.46*

2.25 ± 0.19

0.15 ± 0.05

113.83 ± 15.58*

47.17 ± 4.64

626.5 ± 55.83*

77.67 ± 8.38

27.25 ± 4.65

0.67 ± 0.82

41.17 ± 6.49

10.33 ± 0.43

18.57 ± 2.73

Note. Data are mean ± SD (n = 6 animals). Asterisk indicates significantly different from the control group at p < .05. Abbreviations: total protein (T.P), albumin (ALB), glucose (GLU), total cholesterol (T.CHOL), total bilirubin (T.BIL), glutamate pyruvate transaminase (GPT), glutamate oxaloacetate transaminase (GOT), alkaline phosphatase (ALP), blood urea nitrogen (BUN), triglyceride (TG), g-gluamyl transferase (GGT).

a Treated with corn oil.

Table 4. Summary of Sperm Analysis in DUP-Treated Animals

Parameter

CON a

DUP

Sperm count (106/g)

2568.00 ± 154.90

1851.67* ± 214.49

Motility (%)

74.67 ± 4.51

27.50* ± 6.66

VAP (μm/s)

114.00 ± 10.02

93.82 ± 16.24

VSL (μm/s)

90.46 ± 9.35

64.22 ± 15.68

VCL (μm/s)

261.28 ± 17.94

217.33* ± 18.59

ALH (μm)

14.58 ± 1.19

12.60 ± 3.99

BCF (Hz)

25.62 ± 1.68

20.82 ± 3.64

STR (%)

71.33 ± 3.33

57.67* ± 8.39

LIN (%)

31.50 ± 1.76

25.17* ± 2.48

Note. Data are mean ± SD (n = 6 animals). Asterisk indicates significantly different from the control group at p < .05. Abbreviations: average path velocity (VAP), straight-line velocity (VSL), curvilinear velocity (VCL), amplitude of the lateral head displacement (ALH), beat cross frequency (BCF), straightness (STR), and linearity (LIN).

a Treated with corn oil.

Conclusions:
In a 28-d repeated dose toxicity study with DUP, effects in sperm count and sperm motility of Sprague-Dawley male rats were observed at a dose of 500 mg/kg bw/day.



Executive summary:

In a short-term repeated dose toxicity study similar to OECD guideline 407, diundecyl phthalate (DUP) diluted in corn oil was administered orally to Sprague-Dawley male rats at 500 mg/kg body weight (bw)/d for 4 weeks. Concurrent vehicle was tested as negative control. Examinations and observations included clinical signs, mortality, dietary consumption, body weight, haematology, biochemistry and urine analysis. At the end of the study period animals were sacrificed and heart, lung, liver, kidneys, adrenal glands, spleen, thymus, thyroid glands, testes, and epididymides were weighed, and organ to body weight ratios were calculated. Furthermore, the right cauda epididymis from each of the animals was used for the sperm count analysis, and the left cauda epididymis was used for the motility analysis. No mortality or significant clinical signs were observed. There were no significant effects compared to control in food consumption, body and relative organ weights, haematology, biochemistry and urinalysis findings. Glucose, glutamate oxaloacetate transaminase (GOT) and alkaline phosphatase (ALP) levels in the treatment group were significantly higher than in the control group. Also, sperm count and sperm motility in the treated group were significantly lower than in the control.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
19.28 mg/kg bw/day
Study duration:
chronic
Species:
rat
Quality of whole database:
A weight of evidence approach has been applied. Several experimental studies are available with a Klimisch score of 2 or 4.

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

Weight of evidence from experimental results with the test substance or some analogues:

DUP (21 days, rats, oral):

DUP was tested for its ability to produce peroxisome proliferation in Fischer 344 rats. DUP was administered in the diet of 5 females and 5 males per group for a period of 21 days at levels of 2.5%. The electron microscopic examination of samples of liver from rats showed it to cause a moderate proliferation of peroxisomes. This was accompanied to various extents at all dose levels by, changes in other measurements that have been associated with peroxisome stimulation. These measurements were liver weight increases (absolute and relative to bodyweight), greater activities of palmitoyl CoA oxidation and lauric acid hydroxylation and, in males, lower concentrations of serum triglycerides and cholesterol.

DUP (28 days, rats, oral):

In a short-term repeated dose toxicity study similar to OECD guideline 407, diundecyl phthalate (DUP) diluted in corn oil was administered orally to Sprague-Dawley male rats at 500 mg/kg body weight (bw)/d for 4 weeks. No mortality or significant clinical signs were observed. There were no significant effects compared to control in food consumption, body and relative organ weights, haematology, biochemistry and urinalysis findings. Glucose, glutamate oxaloacetate transaminase (GOT) and alkaline phosphatase (ALP) levels in the treatment group were significantly higher than in the control group. Also, sperm count and sperm motility in the treated group were significantly lower than in the control.

DINP (2 years, rats, oral):

A 2-year repeated dose toxicity study (diet route) was performed on diisononyl phthalate (DINP) according to a method similar to OECD guideline 453. Groups of 110 Fischer 344 rats/sex were fed test substance at dietary levels of 0, 0.03, 0.3, and 0.6 wt% for periods up to 2 years. At study termination, survival was higher than 60% for every group. At the mid or high dose, the following biological effects were noted: slight decreases in food consumption and body weight; slight increase in mortality; a dose-related increase in relative organ weights of liver and kidney; and some slight effects on urinalysis, hematologic, and clinical chemistry parameters. No peroxisome induction was observed in livers of treated rats compared with controls. No clear treatment-related nonneoplastic or neoplastic lesions were found. A clear NOEL was demonstrated for all biological end points at a dietary level of 0.03 wt% or approximately 17 mg/kg/day of DINP. Based on these results, the read-across approach was applied and the NOEL for diundecyl phthalate (DUP) was determined to be 19.28 mg/kg bw/day in rats.

DINP (90 days, monkeys, oral):

A 13-weeks repeated dose toxicity study in marmosets was performed following a method similar to OECD guideline 409 to assessed the systemic toxicity of di-isononyl phthalate (DINP), and also its potential for hepatic peroxisome proliferation. 3 groups of 4 males and 4 females were administered test material diluted in an emulsion of 1% methylcellulose plus 0.5% Tween by oral gavage at dosages of 100, 500 and 2500 mg/kg bw/day. Only vehicle as negative control and clofibrate administered at dosage of 500 mg/kg bw/d as positive control were tested concurrently. To assess the peroxisome proliferation in liver the following parameters were analysed: protein concentration, cyanide-insensitive palmitoyl CoA oxidase activity, cytochrome P450 concentration and lauric acid hydroxylase activity. Results for systemic toxicity showed only minor changes in some clinical signs, body weight gain and apparent thin build revealed at necropsy for one male and one female at 2500 mg/kg bw/day dose group. No statistically significant or treatment-related changes in any of the parameters analysed for peroxisome proliferation were seen following administration of DINP. There were no treatment-related histopathological changes. In conclusion, DINP did not produce any evidence of significant toxicity at 2500 mg/kg bw/day but based on minor changes found at this dosage level the NOEL was considered to be 500 mg/kg/day. Based on these results, the read-across approach was applied and the NOAEL for diundecyl phthalate (DUP) was calculated to be 2835.10 mg/kg/day and the NOEL was calculated to be 567.02 mg/kg/day.

DIDP (90 days, rats/dogs, oral):

The study collects toxicity data relating to the phthalic acid esters used in food packaging. The available information indicates that the levels of phthalates occurring in the diet from authorized uses do not pose any toxicological hazard. It is recognized that this statement is based in part on the premise that phthalates as a class are metabolized in a similar manner, thus allowing a general approach to the toxicity of these compounds. After 13 weeks of oral exposure, the NOEL of DIDP was equal to 75 mg/kg bw/day in dogs and 150 mg/kg bw/day in rats. Based on these results, the read-across approach was applied and the NOEL for diundecyl phthalate (DUP) was calculated to be 79.71 mg/kg/day in dogs and 159.42 mg/kg bw/day in rats.

Justification for classification or non-classification

Based on the available data, the substance is not classified for specific target organ toxicity by repeated exposure (STOT-RE) according to CLP Regulation (EC) no 1272/2008.