N,N,N',N'-tetramethylhexamethylenediamine

Endpoint summary

Description of key information

Studies of acute oral, dermal and inhalation toxicity are available. Mortality and toxicity seen in the acute oral and dermal toxicity studies are attributable to local corrosivity. Mortality seen in one acute inhalation toxicity study is also associated with local effects.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Not specified

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 401 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

There is no information on the purity of test, the source and age of the animals, the period of acclimation, on housing and environmental conditions and on how often the clinical signs and mortality were checked.

GLP compliance:

no

Remarks:

GLP was not mandatory when the study was carried out

Test type:

standard acute method

Limit test:

no

Specific details on test material used for the study:

- Name of test material (as cited in study report):NIAX Catalyst C-210
- Purity: As supplied
- Physical state: transparent, pale yellow, non-viscous liquid

Species:

rat

Strain:

other: Hllltop-Wi.tar albino

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 200 - 300 g
- Fasting period before study: Fasted overnight before dosing
- Diet (e.g. ad libitum): ad libitum
- Water: ad libitum

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

No information

Doses:

First test
0.125, 0.25, 0.5 and 1 mL/kg TMHD
Second test:
The acute oral test was repeated using a 5% (v/v) dilution in distilled water.
0.125, 0.25, 0.5, 0.71 and 1 mL/kg TMHD

No. of animals per sex per dose:

5 animals/sex/dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animal weights are recorded at days 0 (before dosing), 7 and 14 days (just prior to sacrifice).
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs and body weights

Statistics:

LD50's are calculated by the moving average method (Thompson, 1947).

Sex:

male

Dose descriptor:

LD50

Effect level:

0.42 mL/kg bw

Based on:

test mat.

Remarks on result:

other: All the females died in the highest dose group. 4/5 female rats died in the 0.5 mL/kg dose group and 2 female died in the 0.25 mL/kg dose group. The 0.125 mL/kg dose group was not considered relevant because the small volume were difficult to administer.

Sex:

male

Dose descriptor:

LD50

Effect level:

336 mg/kg bw

Based on:

test mat.

Remarks on result:

other: relative density = 0.8

Sex:

female

Dose descriptor:

LD50

Effect level:

0.297 mL/kg bw

Based on:

test mat.

Remarks on result:

other: All the females died in the highest dose group. 4/5 female rats died in the 0.5 mL/kg dose group and 2 female died in the 0.25 mL/kg dose group. The 0.125 mL/kg dose group was not considered relevant because the small volume were difficult to administer.

Sex:

female

Dose descriptor:

LD50

Effect level:

238 mg/kg bw

Based on:

test mat.

Remarks on result:

other: relative density = 0.8

Mortality:

Undiluted test substance
At the highest dose level (1 mL/kg): 5/5 males died on day 1 and all females died on day 1..
At 0.5 mL/kg dose: 2 males died on day 1 and 1 male died on day 7. 3 females died on day 2 and one female died on day 3.
At 0.25 mL/kg: one male died on day 7. One female died on day 2 and the se second one on day 8.
At 0.125 mL/kg: one male died on day 2 and 2 males died on day 4. One female died on day 2 and 2 females died on day 3. However, due to the difficulties in administering this volume, this dose level was no considering when setting the LD50.
5% v/v dilution:
At the highest dose level (1 mL/kg): 3/5 males died on day 0 an 2/5 males died on day 1 and 3/5 females died on day 0 an 2/5 females died on day 1.
At 0.71 mL/kg dose: 3/5 males died on day 3 and 1 male died on day 4. No data reported or females.
At 0.5 mL/kg dose: No death was reported in males. 1 female died on day 2 and one female died on day 3.
At 0.25 mL/kg: No death was reported in males. 1 female died but the time is not reported.
At 0.125 mL/kg: All the animals survived.

Clinical signs:

other: Undiluted test material The following clinical signs were reported for males: 1.0 mL/kg dose group: sluggishness at 15 minutes. 0.5 mL/kg dose group: sluggishness at 20 minutes, red crusty discharge on nose and eye area at day 1 (one animal recovered

Gross pathology:

At gross pathology, the following findings were noted in the groups treated with the undiluted test material mottled and red lung (in male and females), red fluid In the stomach (in males and females), ulceration of the stomach, mucosa and gas or liquid-filled intestines (in females).
At gross pathology, the following findings were noted in the groups treated with the diluted test material pale red lungs stomach and lntestines filled with dark red liquid and with fluid in the thoracic cavity. Nothing remarkable was noted in the survivors.

Interpretation of results:

Category 3 based on GHS criteria

Conclusions:

Based an the results of thls study, the acute oral LD50 for TMHD in the rat should be considered to be 0.420 mL/kg (equivalent to 336 mg/kg) for males and 0.297 mL/kg (equivalent to 238 mg/kg) for females.

Executive summary:

Groups of five Hilltop-Wistar 344 rats/sex/dose were administered a single dose of the undiluted test material by gavage at the following doses 0.125mL/kg, 0.25, 0.5 and 1 mL/kg NIAX Catalyst C-210. The animals were observed for mortality, clinical signs during a 14-day observation period. Body weights were recorded on days 0, 7 and 14 post dosing. Gross pathology was carried out on all animals. All female and male rats died in the 1 mL/kg. 3/5 males and 4/5 males died in the 0.5 mL/kg group. At 0.25 mL/kg, 1/5 male and 2/5 females were reported dead. 3/5 males and 3/5 females died in the 0.1 mL/kg treated group. However this last dose group was not considered in the derivation of the LD50 due to difficulties in administering such a low dosage. Based on the results of this study, the acute oral LD50 for TMHD in the rat should be considered to be 0.420 mL/kg (equivalent to 336 mg/kg bw) for males and 0.297 mL/kg (equivalent to 238 mg/kg bw) for females. It is therefore concluded that the substance classified as Acute Tox Cat. 3 under Regulation (EC) No 1272/2008 and is assigned the hazard statement H301 "Toxic if swallowed".

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

238 mg/kg bw

Quality of whole database:

Lowest reported value

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

December 6th, 1984 to June 6th, 1985

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 403 (Acute Inhalation Toxicity)

Deviations:

yes

Remarks:

No information on the purity, the source and age of the animals, the period of acclimation, on housing and environmental conditions, no analytical method used to monitor the concentration of test material and how the dose was selected

GLP compliance:

no

Remarks:

[not mandatory at the time of the study]

Test type:

standard acute method

Limit test:

yes

Specific details on test material used for the study:

- Name of test material (as cited in study report): tetramethylhexamethylene diamine
- Physical state: Liquid
- Stability under test conditions: Unlimited in closed container
- Storage condition of test material: Room temperature

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, Kingston, New York
- Age at study initiation: No indicated
- Weight at study initiation: 130-180 g
- Fasting period before study: Animals had no access to food or water during exposure.
- Housing: During non-exposure periods, rats were housed singly in suspended stainless steel cages, During exposure animals were housed individually in plastic tubes.
- Diet (e.g. ad libitum): Purtna Rodent Chow #5001 ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 2 weeks

ENVIRONMENTAL CONDITIONS
- Temperature and humidity were recorded hourly during the exposure.
- Light cycle 12 hours light/12 hours darkj

IN-LIFE DATES: From: December 12th, 1984 To: December 21st, 1984

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

head only

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: DeVilbiss Nebuliser fed through teflon tubling by a plastic syringe on a Sage Pump Model 355
- Method of holding animals in test chamber: Head-only
- Source and rate of air: 10L/min
- Method of particle size determination: Andersen Cascade Impactor


TEST ATMOSPHERE
- Brief description of analytical method used: Samples were taken at hourly intervals and analysed by a gravimetric technique. The airborne aerosol concentration was calculated by dividing the weight of the material collected on a Millipore microfiber glass filter paper in a millipore filter paper holder, by the volume of air sampled (liters).

Analytical verification of test atmosphere concentrations:

yes

Remarks:

Gravimetric technique

Duration of exposure:

4 h

Concentrations:

0.41 ( ± 0.15) mg/L

No. of animals per sex per dose:

5 animals/sex/dose

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing:toxic effects were noted twice daily from day 1 to 14. Prior to exposure animals were observed and detailed observations were recorded. Body weights were recorded for Groups Ia and IIA on days 0, 1 and 4. Groups Ib and IIb were recorded on days 0, 1, 4, 7, 11 and 14.
- Necropsy of survivors performed: yes/no
- Other examinations performed: Neurological screening was carried out on days 0, 1, 4, 7 and 14 for Group Ib and IIB and on days 0, 1, 4 for Groups Ia and IIA. Groups Ia and IIa were satellite groups included to allow assessment of posisble reversible (by days 14) histopathological changes. Groups Ia and IIa were sacrificed on day 4 and groups Ib and IIb were sacrificed 14 days after exposure. Microscopic examination was carried out on selected tissues from the brain, cervical spinal cord, trachea, lungs, thymus., kidneys and spleen from all anmals, and a small number of other tIssues tound to have apparent macrospcopic lesions at necropsy.

Statistics:

The analysis of variance were used to compare the treated group versus the control group s for body weight changes or organ weight changes. The Duncan's procedure is used if F for analysis of variance is significantly high to delineate which groups differ from the controls. If Bartlett's test indicated heterogeneous variance, the F max was used for each group versus the control. If these individual F max tets were not significant or if N1=N2 the Cochran t-test or the Wilcoxon Rank Suan test were used. Contingency table-type data were analyzed by Fischer's Exact Test or RXC Chl Square Test, as appropriate.

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 0.41 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: 40% mortality at this exposure concentration

Mortality:

At 0.41 mg/L. 2/5 males and 2/5 females died.

Clinical signs:

other: The following clinical signs were reported in the treated animals yellow staining of the anal-genital region, brown staining of the anal-genital region, red or mucoid, nasal discharge. dried material around nose, eyes and/or mouth, moist rales,

Remarks:

laboured breathing, gasping, rapid breathing, cold to touch, rough coat, reduced activity and thinness in both sexes, with poor condition and distended abdomen observed in males only.

Body weight:

Mean body weights for treated animals of both sexes were significantly reduced compared to controls on days 1 to 7. Treated males showed a significant loss compared to control from day 1 until study termination. (day 14) while treated female showed a significant reduction compared to controls until day 7.

Gross pathology:

Treatment related gross necropsy observations included alopecia, and dried material around the nose, mouth and eyes, gaseous dilatlon of the lntestines and/or stonmach. and dark red colored lungs (discolored lungs were observed in all four spontaneous death animals).
Two males and two female rats died during the course of the study. One male showed marked lymphoid depletion of both the thymus and spleen that were deemed to be treatment related. This animal had also multifocal marked haemorrhagic gastritis. Subtle treatment related changes in the spleen and thymus were reported in Group IIa (terminated 4 days after exposure). The splenic changes were characterised by necrosis of the erythrocytic precursor cells. This was reversed by day 14 in Group IIb. Splenic extramedullary haematopoiesis was slightly increased in some rats in Group IIb. It may have been associated with a rebound phenomena secondary from a prior treatment-induced depression of erythrocytic production. Other tissue alterations were noted however these were not deemd to be treatment related.
Lymphoid depletion/necrosis of the thymus was noted in all mals and 3/5 females after 4 days post exposure but was reversed by day 14.

Other findings:

Changes in absolute thymus and spleen weight were considered statistically significant in both sexes in Group IIa when compared to control. Changes in absolute brain, liver, testes, and both kidneys weight were considered statistically significant in maless in Group IIa when compared to control. Statistically significant difference was also reported in male in absolute thymus weights in Group IIb at study termination when compared to control. Absolute thymus weights were significantly decreased in males until study termination. One set of relative kidney weights were increased.

Interpretation of results:

Category 3 based on GHS criteria

Conclusions:

40 % mortality was seen in this study at the single exposure concentration of 0.41 mg/L. Based on the results of this study, the LC50 can be estimated to fall in the range 0.5 - 1.0 mg/L. Classification of the substance in Category III for acute inhalation toxicity is therefore considered appropriate.

Executive summary:

Groups of five Fischer 344 rats/sex were exposed to a single dose of the undiluted test material for 4 hours at 0.41 mg/L TMHDA. Groups Ia (control) and IIa (treated animals) were terminated after a 4 day observation period. Groups Ib (control) and IIb (treated animals) were terminated after a 14 day observation period. The animals were observed for toxic effects twice daily. Neurological screens were performed on Days 0, 1, 4, 7 and 14 for animals in groups Ib and IIb and on days 0, 1 and 4.   Body weights were recorded on days 0, 1 and 4 for Groups Ia and IIa and on days 0, 1, 4, 7, 11 and 14 for Groups Ib and IIb. Necropsy was carried out at the end of the study on all animals. Organ weights and relative organ weights (brain, thymus, lungs with trachea, liver, spleen, each kidney and gonads) were also recorded. At necropsy, gross pathology was performed and microscopic evaluation of brain, cervical spinal cord, trachea, lungs, thymus, kidneys and spleen from all animals, and a small number of other tissues found to have apparent macroscopic lesions at necropsy. Two out of 5 males and 2 out of 5 females died during the course of the study. Local effect such as respiratory and nasal irritation was reported. Mean body weights for all treated animals were statistically significantly lower than controls between day 1 and 7 post treatment. Reduction in bodyweight gain was also noted in treated males when compared to control between day 1 and study termination. Females also showed lower bodyweight gain until day 7. At gross pathology and microscopic evaluation, reversible effects on the spleen and thymus were noted. These conclusions were based on a reduction in absolute thymus weights and necrosis of erythrocytic precursor cells (extramedullary haematopoiesis). Based on a 40% mortality at 0.41 mg/L, as a conservative approach it is considered that the LC50 is between 0.5 and 1 mg/L and therefore the substance is classified as "Toxic if inhaled" and is assigned H331.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LC50

Value:

410 mg/m³ air

Quality of whole database:

Three studies of acute inhaltion toxicity are available, of which two are considered to be reliable.

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Feb 1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

(1981-05-12)

Deviations:

yes

Remarks:

limit dose level: 400 mg/kg bw (recommended dose level by guideline 2000 mg/kg bw)

GLP compliance:

no

Remarks:

(GLP was not mandatory when study was done)

Test type:

standard acute method

Limit test:

yes

Specific details on test material used for the study:

- Name of test material (as cited in study report): N,N,N',N'-Tetramethyl-1,6-hexanediamine
- Analytical purity: 97.5 %
- Expiration date of the lot/batch: 1983-11
- Impurities (identity and concentrations): N,N',N'-Trimethyl-1,6-hexanediamine 2 %

Species:

rabbit

Strain:

Vienna White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Gaukler, Offenbach, Germany
- Weight at study initiation: mean (females): 2.74 kg, mean(males): 3.16 kg
- Housing: individual animals in steel cages, floor area 40 x 51 cm, no bedding
- Diet (e.g. ad libitum): Ovator Solikanin 4 mm; Muskator-Werke Düsseldorf, Germany (about 130 g per day)
- Water (e.g. ad libitum): 250 ml per animal per day, fully demineralized water at workday, on other days: tap water
- Acclimation period: about 8 days before study begin, same housing conditions as during the study

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 26
- Humidity (%): 30 - 70
- Air changes (per hr): 15 - 20
- Photoperiod (hrs dark / hrs light): 12/12

Type of coverage:

occlusive

Vehicle:

water

Details on dermal exposure:

TEST SITE
- Area of exposure: 395 cm²
- Type of wrap if used: inert foil

REMOVAL OF TEST SUBSTANCE
- Washing (if done): washing with warm water
- Time after start of exposure: 24 hrs

TEST MATERIAL
- Concentration (if solution): 30 %

Duration of exposure:

24 hrs

Doses:

400 mg/kg bw

No. of animals per sex per dose:

5 female and 5 male animals

Control animals:

no

Details on study design:

- Duration of observation period following administration: 15 days
- Frequency of observations and weighing: signs and symptoms were recorded several times on day of application and then once per workday. Check for moribund and dead animals twice each workday and once on other days. Check for skin was done 30-60 minutes after removal of occlusive dressing and then each workday. Weighing was done immediately after beginning of the test and after 4, 7, 11 and 15 days
- Necropsy of survivors performed: yes
- Other examinations performed: organ weights, histopathology

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 400 mg/kg bw

Based on:

test mat.

Remarks on result:

other: 0/5 male animals died; 2/5 female animals died after 8 d

Sex:

male

Dose descriptor:

LD50

Effect level:

> 400 mg/kg bw

Based on:

test mat.

Remarks on result:

other: no male animals died

Sex:

female

Dose descriptor:

LD50

Effect level:

ca. 400 mg/kg bw

Based on:

test mat.

Remarks on result:

other: 2/5 female animals died

Mortality:

male animals: 0/5 died
female animals 2/5 died after 8 days

Clinical signs:

other: male animals: apathy from day 1 to 11 female animals: dyspnea at day 4 apathy: from day 1 to day 8 abnormal position, diarrhoe: at day 4

Gross pathology:

Animals that died (females):
Skin: deep necrosis; general passive hyperemia
Sacrificed animals (males and females):
Skin: deep necrosis at the application site with callous thickening of the subcutis and edematization of the muscles
Organs: no abnormalities detected

Other findings:

local findings on male and female animals:
erythema: from day 1 to 6
deep necrosis: from day 1 to 15
edema: from day 1 to 15

Table 1: Mortality

Dose [mg/kg bw]	Toxicological results*	mortality
Males
400	0/5	0%
Females
400	5/5	20%
LD50 > 400 mg/kg bw
* first number = number of dead animals, second number = number of animals used

Interpretation of results:

Category 3 based on GHS criteria

Conclusions:

The substance is classified for acute dermal toxicity in Category 3 (CLP); toxicity is attributable to local corrosivity.

Executive summary:

A test of acute dermal toxicity was conducted on 5 male and 5 female rabbits with the test substance. Substance was applied occlusive at a dose of 400 mg/kg bw. Test deviated from OECD guideline 402 in limitation of dosage to 400 mg/kg bw and the occlusive application. After 8 days 2/5 female animals died whereas all males survived. Therefore a mortality of 40 % for female rabbits and 0 % for male rabbits can be derived resulting in a LD50 > 400 mg/kg bw.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

discriminating dose

Value:

400 mg/kg bw

Additional information

Three studies of acute oral toxicity in the rat are available for the substance and report comparable results. One study (BASF AG, 1983) reports an acute oral LD50 of 316 - 464 mg/kg bw. Derelanko (1985) reports an acute oral LD50 value of 0.25 - 0.5 mL/kg bw (equivalent to 200 - 400 mg/kg bw based on the reported density of 0.8 g/mL). Myers (1983) reports acute oral LD50 values of 0.420 mL/kg bw (336 mg/kg bw) for males and 0.297 mL/kg bw (238 mg/kg bw) in females. Effects in the acute oral toxicity studies are associated with local corrosivity in the gastrointestinal tract.

Two studies of acute dermal toxicity studies are available for the substance. One study in the rabbit (BASF AG, 1982) reports an acute dermal LD50 value in excess of 400 mg/kg bw; only one dose level was used in this study and was associated with 20 % mortality. A second study of acute dermal toxicity in the rabbit (Myers, 1983) reports an acute dermal LD50 value of 0.492 mL/kg bw (394 mg/kg bw). Effects in these studies are associated with local corrosivity.

Three studies of acute inhalation toxicity are available for the substance. One study (BASF, 1982) reports an LC50 in excess of a vapour concentration of 1.54 mg/L. No mortality observed was observed at this exposure concentration. A second study (Anonymous) similarly reports an absence of mortality at the (unquantified) saturated vapour concentration. A third study performed using liquid aerosols of the substance reports 40 % mortality at the single exposure concentration of 0.41 mg/L.

Justification for classification or non-classification

Based on the range of acute oral LD50 values reported, classification in CLP Category 3 for acute oral toxicity is appropriate. Based on the acute dermal LD50 value of 394 mg/kg bw; classification in CLP Category 3 for acute dermal toxicity is appropriate. 40 % mortality was seen in this study at the single exposure concentration of 0.41 mg/L. Based on the results of this study, the LC50 can be estimated to fall in the range 0.5 - 1.0 mg/L. Classification of the substance in CLP Category 3 for acute inhalation toxicity is therefore considered appropriate.