Hydrocarbons, C17-C19, n-alkanes, <2% aromatics

Endpoint summary

Description of key information

Adsorption / desorption:

Hydrocarbons, C17 -C19, n-alkanes, <2% aromatics are hydrocarbon UVCBs. Standard tests for this endpoint are intended for single substances and are not appropriate for this complex substance. However, this endpoint is characterised using quantitative structure property relationships for representative hydrocarbon structures that comprise the hydrocarbon blocks used to assess the environmental risk of this substance with the PETRORISK model (see Product Library in PETRORISK report attached in IUCLID section 13).

Adsorption coefficient has been calculated using Petrorisk.  The Koc for Hydrocarbons, C17 -C19, n-alkanes, <2% aromatics ranges from 1.20 x10^4 - 2.14 x10^8.

The following data on other representative substances have been included as a weight of evidence. The data is estimated using the calculation in the Concawe Library of Petrorisk, using SPARC v4.2 program (May 2008).

 

K_oc of icosane has been estimated by calculation in the Concawe Library of Petrorisk, using SPARC v4.2 program (May 2008). The calculated value is 1.84 x 10¹¹ L/kg, using a log Kow of 11.46. This result suggests that icosane is expected to be immobile in soil.

Henry's Law Constant (Volatility):

Volatilisation is dependent on Henry's Constant (HC) which is not applicable to complex substances.

Standard tests for atmospheric oxidation half-lives are intended for single substances and are not appropriate for these complex substances. However, this endpoint is characterized using quantitative structure property relationships for representative hydrocarbon structures that comprise the hydrocarbon blocks used to assess the environmental risk of these substances with the PETRORISK model (see library tab in PETRORISK spreadsheet attached to IUCLID section 13).

 

Henry's law constant for icosane has been estimated in the Concawe library, using SPARC v4.2 program. The obtained value is 55.6 atm-m³/mol.

Distribution modelling:

The distribution of C14-20 Aliphatics (≤2% aromatic) in the environmental compartments, air, water, soil, and sediment, has been calculated using the PETRORISK Model, version 5.2. Computer modeling is an accepted method for estimating the environmental distribution of chemicals. Distribution modeling results are included in the 'Multimedia distribution modeling results' tab in the PETRORISK spreadsheet attached to IUCLID section 13.

Based on the regional scale exposure assessment, the multimedia distribution of Hydrocarbons, C13-C18, n-alkanes, isoalkanes, cyclics, <2% aromatics is 0.45 % to air, 0.95 % to water, 8.8 % to soil and 89.8% to sediment.

Based on the regional scale exposure assessment, the multimedia distribution of Hydrocarbons, C14-C16, n-alkanes, <2% aromatics is 5.28 %to air, 0.37% to water, 7.01% to soil and 87.34% to sediment.

Based on the regional scale exposure assessment, the multimedia distribution of Hydrocarbons, C14-C18, n-alkanes, isoalkanes, cyclics, <2% aromatics is 4.1% to air, 0.34% to water, 6.96 % to soil and 89% to sediment.

Based on the regional scale exposure assessment, the multimedia distribution of Hydrocarbons, C14-C20, n-alkanes, <2% aromatics is 0.65% to air, 0.40% to water, 7.44% to soil and 91.51% to sediment.

Based on the regional scale exposure assessment, the multimedia distribution of Hydrocarbons, C14-C20 (even numbered), n-alkanes, isoalkanes, <2% aromatics is 22% to air, 0.31% to water, 5.97% to soil and 72% to sediment.

Based on the regional scale exposure assessment, the multimedia distribution of Hydrocarbons, C16-C20, n-alkanes, isoalkanes, cyclics, <2% aromatics is 1.81% to air, 0.078% to water, 6.96% to soil and 90% to sediment.

Based on the regional scale exposure assessment, the multimedia distribution of icosane is 0.56% to air, 0.02% to water, 7.68% to soil and 91.74% to sediment.

Based on the regional scale exposure assessment, the multimedia distribution of hexadecane is 5.13% to air, 0.1% to water, 89.03% to sediment and 5.74% to soil.