Registration Dossier

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
No information; study reported in 1975
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Older, proprietary and guideline-comparable study pre-dating the introduction of GLP

Data source

Reference
Reference Type:
other company data
Title:
Unnamed
Year:
1975
Report Date:
1975

Materials and methods

Test guidelineopen allclose all
Qualifier:
no guideline followed
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Principles of method if other than guideline:
Standard acute oral toxicity study method comparable to OECD 401, but performed prior to the adoption of this guideline
GLP compliance:
not specified
Remarks:
: older study, pre-dates GLP
Test type:
standard acute method
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
not specified
Details on test material:
Terephthalic acid TA-12. The purity was not stated. However, terephthalic acid is a monomer used in the production of saturated polyesters, and a purified (> 99.9% w/w) feedstock (free of production-process impurities) is essential for this purpose. The batch of terephthalic acid used in this study is considered to have been representative of commercial production and to have been at least 99% pure.

Test animals

Species:
rat
Strain:
not specified
Sex:
male/female
Details on test animals and environmental conditions:
Male and female albino rats

Administration / exposure

Route of administration:
oral: unspecified
Vehicle:
corn oil
Details on oral exposure:
Terephthalic acid was administered orally to rats as a 40% (w/v) homogenous suspension in corn oil
Doses:
6834, 10250, and 15380 mg/kg bw.
No. of animals per sex per dose:
5 rats per sex per dose
Control animals:
no
Details on study design:
The test substance was administered orally at three dose levels to groups of 5 male and 5 female albino rats. Rats were observed for clinical signs and mortality for 14 days post administration. Necropsy was performed on all rats that died during the test, and on all surviving rats at the end of the 14 day observation period. Body weights were recorded on test days 0 and 14.
Statistics:
Not applicable - not required

Results and discussion

Preliminary study:
Not applicable
Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 15 380 mg/kg bw
Based on:
test mat.
Remarks on result:
other: No deaths at the highest dose level
Mortality:
The only deaths that occurred were in the mid dose group (10250 mg/kg); 1 female died within 22 hours of administration, and 1 male died on day 3.
Clinical signs:
Clinical signs observed at all dose levels included hypoactivity, ruffled fur, diarrhoea, muscular weakness and rhinitis
Body weight:
1 female rat in the high dose group lost 4 g bodyweight during the test, all other rats in this group and the two lower doses gained weight during the 14 day observation period.
Gross pathology:
The two rats that died before the end of the study were found to have pale discoloured kidneys at necropsy. Examination of the rats surviving to the end of the 14 day observation period did not reveal any gross pathologic alterations.
Other findings:
No other findings reported.

Any other information on results incl. tables

The onset and recovery of clinical signs observed in rats following oral administration with terephthalic acid is shown below.

Clinical signs

Dose level of terephthalic acid (mg/kg bw)

6834

10250

15380

Onset

Recovery

Onset

Recovery

Onset

Recovery

Hypoactivity

6-22 h

3 d

30 m

6 d

30 m

7 d

Ruffled fur

6-22 h

3 d

30 m

6 d

30 m

6 d

Diarrhoea

6-22 h

2 d

6-22 h

4 d

1 h

5 d

Muscular weakness

6-22 h

2 d

6-22 h

5 d

6-22 h

5 d

Rhinitis

-

-

2 d

6 d

6-22 h

6 d

d =days, h =hours, m =minutes

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated informationCriteria used for interpretation of results: EU
Conclusions:
The acute oral LD50 of terephthalic acid in rats is greater than 15380 mg/kg bw.
Executive summary:

Terephthalic acid in corn oil was administered orally by gavage to male and female rats at dose levels of 6834, 10250 and 15380 mg/kg bw. Rats were observed for 14 days following administration. The only deaths that occurred were in the mid dose group (10250 mg/kg bw); 1 female died within 22 hours of administration, and 1 male died on day 3. Gross necropsy revealed that these rats had pale discoloured kidneys. Clinical signs observed at all dose levels included hypoactivity, piloerection, diarrhoea, muscular weakness and rhinitis. Minimal transient weight loss was observed in individual animals; however there were no effects on body weight gain over the 14-day study period. Gross necropsy of all animals surviving to the end of the 14-day observation period did not reveal any abnormalities. The acute oral LD50 of terephthalic acid in the rat is therefore shown to be >15380 mg/kg bw under the conditions of this study.