Trihexyl phosphate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 - 30 May 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

adopted in 2017

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Slovenska Narodna Akreditacna Sluzba, Bratislava, Slovenska Republika

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Trihexyl phosphate

EC Number:

219-774-8

EC Name:

Trihexyl phosphate

Cas Number:

2528-39-4

Molecular formula:

C18H39O4P

IUPAC Name:

trihexyl phosphate

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dobrá Voda, Slovak Republic
- Females nulliparous and non-pregnant: yes
- Age at study initiation: 8-9 weeks
- Housing: 1-3 animals per cage in plastic cages suspended on stainless steel racks on Lignocel S3/4 bedding (Lufa-ITL GmbH, Germany)
- Diet: laboratory food ssniff (Spezialdiäten GmbH, Germany), ad libitum (analyses were performed)
- Water: tap water, ad libitum (analyses were performed)
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22.6 ± 0.56
- Humidity (%): 54.34 ± 2.71
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: dorsal area of the trunk
- % coverage: 10
- Type of wrap if used: semi-occlusive dressing with non-irritating tape

REMOVAL OF TEST SUBSTANCE
- Washing: with lukewarm water
- Time after start of exposure: 24 h

Duration of exposure:

24 h

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

3 females

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations: Animals were observed individually immediately after the application of the test item and then 0.5, 1, 2, 4 and 6 hours later. Each animal was inspected daily for the next 14 days. Observations included changes in skin and fur, eyes and mucous membranes, and also respiratory, circulatory, autonomic and central nervous systems, and somatomotor activity and behaviour pattern. Attention was directed to observations of tremors, convulsions, salivation, diarrhoea, lethargy, sleep and coma. In addition, the treatment site was observed at 24, 48 and 72 hours after removal of test item using the Draize criteria.
- Body weights: Individual weights of animals were determined shortly before the test item was applied and weekly thereafter.
- Necropsy of survivors performed: yes

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality was observed during the study

Clinical signs:

No clinical signs of intoxication, neither change of health nor skin reactions were noted.

Body weight:

The body weights of all animals were increasing during the study. No body weight losses were observed between the first and second week after administration.

Gross pathology:

At necropsy, no macroscopic changes were noted.

Any other information on results incl. tables

Table 1. Body weights

Sex	Dose	ID	Body Weight (g)			Body Weight Difference (g)
			Initial	Week 1	Week 2	Week 1 - Initial	Week 2 - Initial	Week 2 - Week 1
♀	2000 mg/kg bw	1	188	203	211	15	23	8
		2	193	198	200	5	7	2
		3	201	205	212	4	11	7

Applicant's summary and conclusion

Interpretation of results:

other: CLP/ EU GHS criteria not met, no classification required according to Regulation (EC) No 1272/2008

Conclusions:

In this acute dermal toxicity limit study a LD50 value > 2000 mg/kg bw infemale rats was derived.