Pitch, petroleum, arom.

Endpoint summary

Description of key information

No particular acute toxicity was observed in experimental studies after single oral administration of coal tar pitch, high temp., a closely structure related pitch and after dermal administration of petro pitch itself. LD50 values were > 15000 mg/kg bw/day (oral, coal tar pitch) and > 2000 mg/kg bw/day  (dermal, petro pitch). No mortality and no other signs of toxicity were observed in both studies.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

03 June - 03 July 1987

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Wiga, Sulzfeld/Germany
- Age at study initiation: no data
- Weight at study initiation: 180.0 - 200.0 g (m); 151.9 - 181.9 g (f)
- Fasting period before study: 16 h
- Housing: max. 5/cage
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: >= 7 d


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +-2 °C
- Humidity (%): 50 - 85
- Photoperiod (hrs dark / hrs light): 12 / 12

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 50 % (w/v)
- Amount of vehicle (if gavage): The TS was applied in a constant volume of 5-% carboxymethylcellulose. 
- Justification for choice of vehicle: inert carrier material for suspending insoluble solids


MAXIMUM DOSE VOLUME APPLIED: 5 mL/kg bw



CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose:
The  dose was derived from a range-finding test and corresponded to the  maximally applicable volume.

Doses:

15000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: day 0 and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, macroscopic organpathology

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 15 000 mg/kg bw

Mortality:

none

Clinical signs:

other: none

Gross pathology:

no particular findings

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

15 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP Guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, Germany
- Age at study initiation: 10 - 12 weeks
- Weight at study initiation: males: 281 - 296 g; females: 190 - 203 g
- Fasting period before study:
- Housing: Makrolon cages, individually
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 5 d

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 +-3
- Humidity (%): 40 - 70 %
- Air changes (per hr): approx. 15
- Photoperiod (hrs dark / hrs light): 12 / 12

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: approx. 10 % of total body surface (males: ~25 cm2; females: ~18 cm2)
- Type of wrap if used: surgical gauze (Surgy 1D), covered with aluminum foil and Coban elastic bandage

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg bw

VEHICLE
- Amount(s) applied (volume or weight with unit):
- Concentration (if solution):
- Lot/batch no. (if required):
- Purity:

Duration of exposure:

24 h

Doses:

2000 mg/kg bw

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: 2x daily for clinical observation, day 1, 8 and 15 for body weight
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Statistics:

not applicable

Sex:

male/female

Dose descriptor:

LD0

Effect level:

2 000 mg/kg bw

Based on:

test mat.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

no

Clinical signs:

other: black and yellow staining of fur and the treated skin area

Gross pathology:

no particular findings

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

Acute toxicity was determined using petro pitch (dermal application) and coal tar pitch, high temp. (oral application), a closely related substance with similar structure and properties. Exposure by inhalation is considered not to be relevant as petro pitch is a solid with a high melting point and a very low vapour pressure. Exposure to vapour, aerosols or particles containing petro pitch is of no concern.

The highest doses tested (oral route: 15000 mg/kg bw/day; dermal route: 2000 mg/kg bw/day) did not produce any mortality. In addition, indicators of other toxic effects could also not be observed.

Justification for selection of acute toxicity – oral endpoint
Valid GLP study according to OECD TG 401, no mortality and no other signs of toxicity observed.

Justification for selection of acute toxicity – dermal endpoint
Valid GLP study according to OECD TG 402, no mortality and no other signs of toxicity observed.

Justification for classification or non-classification

Based on experimental evidence, no classification required (LD50 values clearly above classification criteria of Regulation (EC) No 1272/2008).