Hydrocarbons, C12-C14, isoalkanes, cyclics, <2% aromatics

Endpoint summary

Additional information

Acute Fish Toxicity:

Water accommodated fractions of hydrocarbons, C10-C12, isoalkanes, <2% aromatics, produced a 96-hour LL50 value of >1000 mg/L and LL0 value of 1000 mg/L with rainbow trout, Oncorhynchus mykiss. No mortality was observed in either the control or treatment test systems. The water accommodated fraction of hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, <2% aromatics, produced a 96-hour LL50 value of >1000 mg/L and LL0 value of 1000 mg/L with rainbow trout, Oncorhynchus mykiss. No mortality was observed in either the control or treatment test systems. The data from these two studies are used as read-across data to hydrocarbons, C12-C13, isoalkanes, cyclics, <2% aromatics.

Chronic Fish Toxicity:

The hydrocarbons, C10-C13, isoalkanes, cyclics, <2% aromatics, estimated freshwater fish 28-day NOELR (No Observed Effect Loading Rate) value is 0.088 mg/l based on growth.

Acute Invertebrate Toxicity:

Freshwater:

Water accommodated fractions of hydrocarbons, C10-C12, isoalkanes, <2% aromatics, did not produce a 50% effect (immobility) with Daphnia magna at a loading of 1000 mg/L after a 48-hour exposure. Therefore, the 48-hour LL50 is reported as >1000 mg/L. There was no mortality at the 1000 mg/L loading level after 48 hours. Therefore, the 48-hour LL0 for mortality is reported as 1000 mg/L. There was also no mortality in the control.

The water accommodated fraction (WAF) of hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, <2% aromatics, did not produce a 50% effect (immobility) with Daphnia magna at a loading of 1000 mg/L after a 48-hour exposure. Therefore, the 48-hour LL50 is reported as >1000 mg/L. There was no mortality at the 1000 mg/L loading level after 48 hours. Therefore, the 48-hour LL0 for mortality is reported as 1000 mg/L. There was also no mortality in the control. The data from these two studies are used as read-across data to hydrocarbons, C12-C13, isoalkanes, cyclics, <2% aromatics.

Marine:

The 100% water soluble fraction (WSF) of hydrocarbons, C10-C14, isoalkanes, cyclics, <2% aromatics, at a loading of 81,000 mg/L did not produce a 50% mortality with Mysidopsis bahia after a 96-hour exposure. Therefore, the 96-hour LL50 value is reported as >81,000 mg/L. There was also no mortality in the control. These data are used as read-across data to hydrocarbons, C12-C13, isoalkanes, cyclics, <2% aromatics.

Chronic Invertebrate Toxicity:

The read across test substance C11 -C13, isoalkanes, cyclics, showed no effects on survival, reproduction, or length at a nominal loading of 1 mg/L. Therefore, the 21-Day No Observed Effect Loading Rate (NOELR) = 1.0 mg/L for these endpoints based upon nominal loading level.

In a second 21-day study, the adult daphnids exposed to hydrocarbons, C10-C12, isoalkanes, <2% aromatics, at a loading rate of 1 mg/L produced significantly fewer (<0.05) live offspring per adult than the adult daphnids in the control media. Therefore, the 21-day NOELR for reproduction was reported as <1 mg/L. There was 10% immobility of parents in the treatment solution, which was equivalent to the control mortality, therefore the EL50 can be reported as >1 mg/L. The data from these two studies are used as read-across data to hydrocarbons, C10-C13, isoalkanes, cyclics, <2% aromatics. Here we use the data from C11 -C13 isoalkanes, cyclics as our key study and therefore the apporpriate NOELR because it more closely resembles the composition of the taget substance than does the C10 -C12 isoalkanes which does not contain C13 compounds.

Algal Toxicity:

Growth of alga cultures, as measured by biomass and growth rate, exposed to a water accommodated fraction of hydrocarbons, C10-C12, isoalkanes, <2% aromatics, was not inhibited over 72 hours. The growth of algae in the the test systems was greater than the controls, which performed normally. Therefore, the 72-hr EL50 values for the two endpoints are reported as >1000 mg/L. The 72-hr NOELR values for biomass and growth rate are reported as 1000 mg/L, respectively. Growth of alga cultures, as measured by biomass and growth rate, exposed to a water accommodated fraction of hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, <2% aromatics, was not inhibited over 72 hours. The growth of algae in the the test systems was greater than the controls, which performed normally. Therefore, the 72-hr EL50 values for the two endpoints are reported as >1000 mg/L. The 72-hr NOELR values for biomass and growth rate are reported as 1000 mg/L, respectively. The data from these two studies are used as read-across data to hydrocarbons, C12 -C13, isoalkanes, cyclics, <2% aromatics.

Toxicity to microorganisms:

Isododecane at the highest loading rate, 2 ml/L, did not inhibit the respiration rate of Pseudomonas putida over an exposure period of 5 hours. These data are used as read-across data to hydrocarbons, C12-C13, isoalkanes, cyclics, <2% aromatics. In addition, the hydrocarbons, C10-C13, isoalkanes, cyclics, <2% aromatics, estimated protozoan, Tetrahymena pyriformis, 48-hr EL50 value for this substance is >1000 mg/L based on growth inhibition.