Distillates (petroleum), cracked, ethylene manuf. by-product, C9-10 fraction

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 September - 18 October 1988

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP compliant, guideline study, available as unpublished report, no restictions, fully adequate for assessment.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in Section 13 of the dossier.

Cross-reference

Reason / purpose for cross-reference:

read-across: supporting information

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

no

Principles of method if other than guideline:

Doses of DCPD 75%: 500, 794, 1260 & 2000 mg/kg/bw

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Dicyclopentadiene (DCPD)

IUPAC Name:

Dicyclopentadiene (DCPD)

Constituent 2

Reference substance name:

3a,4,7,7a-tetrahydro-4,7-methanoindene

EC Number:

201-052-9

EC Name:

3a,4,7,7a-tetrahydro-4,7-methanoindene

Cas Number:

77-73-6

Molecular formula:

C10H12

IUPAC Name:

3a,4,7,7a-tetrahydro-1H-4,7-methanoindene

Details on test material:

- Name of test material (as cited in study report): DCPD 75%
- Physical state: clear, yellow-coloured liquid
- Composition of test material, percentage of components: 71.1% endo dicyclopentadiene, 0.8% exo dicyclopentadiene, 1.4% m-bicyclozonadiene, 15.2% CPD-MCPD codimers, 0.3% tricyclopentadiene, 1.3% CPD-butadiene codimer, 0.3% CPD-piperylene codimer, 0.3% CPD-isoprene codimer, <0.1% benzene , remainder misc. hydrocarbons.
- Specific gravity: 0.971
- Storage condition of test material: room temperature

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Interfauna (UK) Ltd., Wyton, Huntingdon, Cambridgeshire
- Age at study initiation: 5-8 weeks
- Weight at study initiation: males 120-146 g; females 120-150 g
- Fasting period before study: overnight
- Housing: In groups of up to 5, sexes separately in solid floor polypropylene cages with sawdust bedding.
- Diet: Rat and Mouse Expanded Diet No. 1 (Special Diet Services Ltd., Witham, Essex, UK) ad libitum (except for overnight fast immediately prior to dosing and approximately 2 hours after dosing)
- Water: Mains drinking water ad libitum
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-21
- Humidity (%): 45-68
- Air changes (per hr): approx 15
- Photoperiod (hrs dark / hrs light): 12 / 12

IN-LIFE DATES: From: 22 September 1988 To: 18 October 1988

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

Maximum dose volume applied: 2.06 mL/kg
Minimum dose volume applied: 0.51 mL/kg

Doses:

500, 794, 1260 and 2000 mg/kg

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observed 1 and 4 hours after dosing and once daily thereafter. Body weights recorded on day of dosing (day 0), days 7, 14 or at death.
- Necropsy of survivors performed: yes

Statistics:

The acute oral LD50 and 95% confidence limits calculated using the probit method.

Results and discussion

Effect levels

Effect levels 1

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

590 mg/kg bw

95% CL:

393 - 886

Effect levels 2

Key result

Sex:

male

Dose descriptor:

LD50

Effect level:

512 mg/kg bw

95% CL:

227 - 1 155

Effect levels 3

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

676 mg/kg bw

95% CL:

444 - 1 030

Mortality:

All deaths occurred one or two days following dosing. There were 2, 4, 5 and 5 male deaths and 1, 2, 5 and 5 females deaths in the 500, 794, 1260 and 2000 mg/kg bw groups respectively.

Clinical signs:

other: Hunched posture, piloerection, lethargy and decreased respiratory rate were present in all animals during the day of dosing. Ptosis was occasionally noted in animals dosed with 794 and 1260 mg/kg during this period. All rats dosed with 2000 mg/kg had ptos

Gross pathology:

Haemorrhagic lungs, dark liver and sloughing of the non-glandular gastric epithelium was seen in decedents. No abnormalities were seen in animals killed at the end of the study.

Applicant's summary and conclusion

Interpretation of results:

other: Harmful if swallowed

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

The acute oral LD50 and 95% confidence limits of DCPD 75% were calculated to be 590 (393 - 886) mg/Kg bw for males and females combined; 512 (227 - 1155) mg/Kg bw for males and 676 (444 - 1030) mg/Kg bw for females.

Executive summary:

Groups of 5 male and 5 female Sprague Dawley rats (fasted overnight) were dosed by gavage at levels of 500, 794, 1260 or 2000 mg/Kg DCPD and were observed daily for 14 days after dosing. At the 4 hour observation period rats dosed with high levels of DCPD (1260 or 2000 mg/Kg bw) had hunched posture, piloerection, lethargy and decreased respiratory rate, with ptosis and occasional signs of ataxia seen in those dosed at 2000 mg/Kg bw . All rats dosed at 1260 or 2000 mg/Kg bw died one or two days after dosing. Haemorrhagic lungs, dark liver and sloughing of the non-glandular gastric epithelium was seen in decedents.

The LD₅₀ was calculated to be 590 mg/Kg bw (male/female), 512 mg/Kg bw for males and 676 mg/Kg bw for females.