Hydrocarbons, C10-C13, n-alkanes, isoalkanes,

Endpoint summary

Description of key information

Phototransformation in air

The available weight of evidence demonstrates that this substance does not absorb light within a range of 290 to 750 nm, the range in which photolysis occurs. Therefore, direct photolysis will not contribute to the degradation of this substance in the air. Further testing is not required under Annex XI, section 1.2.

Hydrolysis

Hydrolysis is a reaction in which a water molecule or hydroxide ion substitutes for another atom or group of atoms present in a chemical resulting in a structural change of that chemical. Potentially hydrolyzable groups include alkyl halides, amides, carbamates, carboxylic acid esters and lactones, epoxides, phosphate esters, and sulfonic acid esters. The lack of a suitable leaving group renders compounds resistant to hydrolysis

The chemical constituents that comprise Hydrocarbons, C10-C13, n-alkanes, isoalkanes, <2% aromatics consist entirely of carbon and hydrogen and do not contain hydrolyzable groups. As such, they have a very low potential to hydrolyze. Therefore, this degradative process will not contribute to their removal from the environment.

Phototransformation in water

The available weight of evidence demonstrates that this substancedoes not absorb light within a range of 290 to 750 nm, the range in which photolysis occurs. Therefore, direct photolysis will not contribute to the degradation of this substance in the aquatic environment. Further testing is not required under Annex XI, section 1.2.

Phototransformation in soil

The direct photolysis of an organic molecule occurs when it absorbs sufficient light energy to result in a structural transformation. The absorption of light in the ultra violet (UV)-visible range, 110-750 nm, can result in the electronic excitation of an organic molecule. The stratospheric ozone layer prevents UV light of less than 290 nm from reaching the earth's surface. Therefore, only light at wavelengths between 290 and 750 nm can result in photochemical transformations in the environment.

A conservative approach to estimating a photochemical degradation rate is to assume that degradation will occur in proportion to the amount of light wavelengths >290 nm absorbed by the molecule.Hydrocarbons, C10-C13, n-alkanes, isoalkanes, <2% aromaticscontains hydrocarbon molecules that absorb UV light below 290 nm, a range of UV light that does not reach the earth's surface. Therefore, this substance does not have the potential to undergo photolysis in water and soil, and this fate process will not contribute to a measurable degradative loss of this substance from the environment.

Biodegradation in water: screening tests

There is data available for this substance. Additionally, key data is also available for structural analogues; Hydrocarbons, C9-C11, cyclics, <2% aromatics; Hydrocarbons, C10-C12, isoalkanes, <2% aromatics; Hydrocarbons, C11-C12, n-alkanes, <2% aromatics, Hydrocarbons, C12-C16, n-alkanes, isoalkanes, cyclics, <2% aromatics, Hydrocarbons, C13-C14, n-alkanes, <2% aromatics; Hydrocarbons, C10-C12, isoalkanes, cyclics, <2% aromatics; Hydrocarbons, C10-C14, isoalkanes, cyclics, <2% aromatics and Hydrocarbons, C12-C13, isoalkanes, cyclics, <2% aromatics and presented in the dossier. The data is read across to this substance based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13.

Biodegradation in water and sediment: simulation tests

Biodegradation in water

There is no data available for this substance. However, key data is available for a structural analogue, Hydrocarbons, C12-C14, isoalkanes, <2% aromatics and presented in the dossier. The data is read across to this substance based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13.

Biodegradation in sediment

This substance is considered readily biodegradable. Therefore, in accordance with REACH Annex IX column 2 exemption, the simulation testing in sediment does not need to be conducted

Biodegradation in soil

This substance is considered readily biodegradable. Therefore, in accordance with REACH Annex IX column 2 exemption, the bidegradation in soil does not need to be conducted.

Bioaccumulation: aquatic/sediment

Standard Bioaccumulation studies for this endpoint are intended for monoconstituent substances and are not appropriate for petroleum UVCB substances. In accordance with Annex XI Section 1.3 the endpoint has been fulfilled using QSAR calculations for representative hydrocarbon structures that comprise the hydrocarbon blocks used to assess the environmental risk of this substance with the PETRORISK model (see the representative structures from the PETRORISK Product Library in the spreadsheet attached in IUCLID section 13.2). As such, testing is not scientifically necessary.

Full justifications for these QSAR are presented in 'Attached justification' within the associated endpoint records, but in brief these are justified because:

-the results are obtained from a QSAR model whose scientific validity has been established

-petroleum substances fall within the applicability domain of the QSAR model

-results are adequate for the purposes of risk assessment

-adequate and reliable documentation is provided

Adsorption / desorption:

Standard adsorption studies for this endpoint are intended for monoconstituent substances and are not appropriate for petroleum UVCB substances. In accordance with Annex XI Section 1.3 the endpoint has been fulfilled using QSAR calculations for representative hydrocarbon structures that comprise the hydrocarbon blocks used to assess the environmental risk of this substance with the PETRORISK model (see the representative structures from the PETRORISK Product Library in the spreadsheet attached in IUCLID section 13.2). As such, testing is not scientifically necessary.

Full justifications for these QSAR are presented in 'Attached justification' within the associated endpoint records, but in brief these are justified because:

-the results are obtained from a QSAR model whose scientific validity has been established

-petroleum substances fall within the applicability domain of the QSAR model

-results are adequate for the purposes of risk assessment

-adequate and reliable documentation is provided

Volatilisation:

Standard Henry's Law Constant studies for this endpoint are intended for monoconstituent substances and are not appropriate for petroleum UVCB substances. In accordance with Annex XI Section 1.3 the endpoint has been fulfilled using QSAR calculations for representative hydrocarbon structures that comprise the hydrocarbon blocks used to assess the environmental risk of this substance with the PETRORISK model (see the representative structures from the PETRORISK Product Library in the spreadsheet attached in IUCLID section 13.2). As such, testing is not scientifically necessary.

Full justifications for these QSAR are presented in 'Attached justification' within the associated endpoint records, but in brief these are justified because:

-the results are obtained from a QSAR model whose scientific validity has been established

-petroleum substances fall within the applicability domain of the QSAR model

-results are adequate for the purposes of risk assessment

-adequate and reliable documentation is provided

Distribution modelling:

The distribution of Hydrocarbons, C10-C13, n-alkanes, isoalkanes, <2% aromatics in the environmental compartments air, water, soil, and sediment, has been calculated using the PETRORISK Model, version 7.04. Computer modelling is an accepted method for estimating the environmental distribution of chemicals. Based on the regional scale exposure assessment, the multimedia distribution of Hydrocarbons, C10-C13, n-alkanes, isoalkanes, <2% aromatics is 15.2% to air, 3.7% to water, 11.4% to soil and 69.7% to sediment. Distribution modelling results are included in the 'Multimedia distribution modelling results' tab in the 2016 PETRORISK spreadsheet attached to the Robust Study Summary (RSS).