Hydrocarbons, C13-C20, n-alkanes, isoalkanes, cyclic, aromatics (40-60%)

Endpoint summary

Description of key information

Based on read-across
Repeated Dose Oral 90d – NOAEL = 1056 mg/kg for rats 
Repeated Dose Dermal 21/28d – NOAEL = 495 mg/kg for rats
Repeated Dose Inhalation 90d – NOAEC = 690 ppm for rats 

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion

Dose descriptor:

NOAEL

1 056 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Dose descriptor:

NOAEC

3 950 mg/m³

Study duration:

subchronic

Species:

rat

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Dose descriptor:

NOAEL

495 mg/kg bw/day

Study duration:

subacute

Species:

rat

Additional information

There are no available data for hydrocarbons, C13-C20, n-alkanes, isoalkanes, cyclics, 40-60% aromatics. However, some investigations on repeated dose toxicity are available for structurally related substances as hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, aromatics.

Oral:

All tests were performed in a manner similar or equivalent to currently established OECD guidelines. The key study examined the oral 90-day subchronic toxicity of hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, aromatics, 2-25% to rats (DHC Solvent Chemie GmbH 1984a). Groups of 5 rats of each sex were given doses of 116 mg/kg, 347 mg/kg, or 1056 mg/kg of test substance in corn oil for 90 days. Animals were examined for clinical signs, mortality, body weight, food consumption, water consumption, and food conversion. After sacrifice clinical chemistry, hematology, clinical chemistry, urinalysis, organ weights, histopathology, and gross pathology were examined. There was no mortality during the experiment. Renal damage was observed in male rats at all dose levels. This type of renal pathology is specific to male rats due to a alpha2u-globulin-mediated process that is not relevant to humans. Female rats exhibited minimal liver changes at the highest dosage. The LOAEL for male rats was 0.14 ml/kg/day based on renal damage. The female NOAEL was 1056 mg/kg; the highest dose tested.

Dermal:

C13-C20 aliphatics and cyclics, 40 -60% aromatics are expected to have a low order of repeated dose toxicity by the dermal route of exposure. Available read-across data from the structurally analogous test material straightrun kerosene was analysed. In the key study, rats were dermally applied with the test substance at concentrations of 165, 330 and 495 mg/kg/day (American Petroleum Institute (1997). Dosing was continued daily for five consecutive days each week, five days a week for 13 weeks. In addition a group of 12 male and 12 female rats of similar age was administered mineral oil as vehicle controls and an additional high dose group was maintained for a 4-week recovery period following dosing for 13 weeks. At the 14 week necropsy, blood samples were collected from 12 animals/sex/group and at the week 18 necropsy from the recovery rats (vehicle and high dose groups). There were no systemic or neurological effects noted at any of the tested doses. The systemic NOAEL was >=495 mg/kg/day. Since no effects were seen at the highest dose tested, a dermal DNEL will be calculated using route to route extrapolation using the key study identified for the oral route.Moreover, in a reliable sub-acute dermal toxicity study conducted similar to OECD 410, rabbits were dosed with concentrations of 200, 1000 or 2000 mg/kg/day kerosene under occlusive conditions for twelve doses (American Petroleum Institute (1985)). Based on the deaths observed in the high dose group, the NOAEL for systemic toxicity was set at 1000 mg/kg/day. In addition three repeated dose dermal toxicity studies are available (summarized in American Petroleum Institute, 2003). Consistent with the study described above, only low systemic toxicity after repeated dermal exposure can be concluded from these studies.

Inhalation:

C13-C20 aliphatics and cyclics, 40-60% aromatics are expected to have a low order of repeated dose toxicity by the inhalation route of exposure. No study was located for the test substance C13-C20 aliphatics and cyclics, 40 -60% aromatics, however, available read-across data from the structurally analogous test material C9-C12 aliphatics, 2-25% aromatics was analysed. The key study evaluated the sub-chronic toxicity of low aromatic white spirits to rats when exposed via inhalation Shell (1980). Groups of 18 rats per sex were exposed to 345, 690, or 1293 ppm of test substance for 6 hrs/day, 5 days/week, for 13 weeks. The highest concentration, 1293 ppm, was near the saturation point for test substance vapor. Rats were observed for clinical signs, mortality, food consumption, water consumption, and body weight. At the end of the exposure period, the animals were sacrificed, and clinical chemistry, haematology, gross pathology, and histopathology parameters were examined. Male rats at all exposure levels had degenerative effects of the as a result of an alpha2u-globulin-mediated process that is not regarded as relevant to humans. The LOAEC was established at 1293 ppm (7400 mg/m3) due to a significant body weight reduction. No other effects were noted. The NOAEC for female rats was 690 ppm (3950 mg/m3).

The following information is taken into account for any hazard / risk assessment:

Based on read-across

Repeated Dose Oral 90d – NOAEL = 1056 mg/kg for rats

Repeated Dose Dermal 21/28d – NOAEL > 495 mg/kg for rats

Repeated Dose Inhalation 90d – NOAEL = 3950 mg/m³for rats

 

Justification for classification or non-classification

Based on read-across the available data on repeated dose toxicity of structurally related substances are conclusive but not sufficient for classification of hydrocarbons, C13-C20, n-alkanes, isoalkanes, cyclics, 40 -60% aromatics.