Dimethyl itaconate

Adsorption / desorption

Description of key information

Irrelevantly low adsorption, high mobility, Koc and Log Koc values obtained by extrapolation

Key value for chemical safety assessment

Koc at 20 °C:

2.5

Additional information

In absence of dissociation and considering the low lipophilicity expressed by an n-octanol/water partition coefficient of 0.86 the adsorption was determined by the HPLC estimation method.

The adsorption properties of the submission item Dimethyl itaconate (CAS 617-52-7) were was measured in a GLP-compliant study (Walker 2014, Harlan Laboratories Report no. 41402218) employing the “Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))” compliant with EU Method C.19 (Commission Regulation (EC) No. 440/2008) and the OECD TG 121 (2001) protocol. The experiment can be considered relevant and adequate for the endpoint, but the submission item eluted out of the calibration range. Because of the little adsorption of the test item, the study is nonetheless deemed conclusive and was rated „reliable with restrictions“, i.e. “Klimisch 2” according to the scale of Klimisch et al. (1997).

Acetanilide (CAS 103-84-4), Phenol (CAS 108-95-2), Atrazine (CAS 1912-24-9), Isoproturon (CAS 34123-59-6), Triadimenol (CAS 55219-65-3), Linuron (CAS 330-55-2), Naphthalene (CAS 91-20-3), Endosulfan-diol (CAS 2157-19-9, Fenthion (CAS 55-38-9), α-Endosulfan (CAS 959-98-8), Phenanthrene (CAS 85-01-8), Diclofop-methyl (CAS 51338-27-3) and DDT (50-29-3) were used as standard references considering the Log Kow values as given in the test guidance. The correlation of fit of the established calibration curve (R²) was 0.9301 demonstrating the reliability of the method in the calibration range from Log Koc 1.25 to 5.63. The column temperature was 30 °C. The test item eluted in one distinctive peak out of the calibration range, after 2.474 min, while the first standard Acetanilide (Log Koc 1.25) was detected after about 2.868 min. Accordingly the adsorption of the test item can be described by Koc < 17.8 and Log Koc <1.25 at 30 °C. The extrapolated Log Koc value was calculated to be approximately 0.39 (Koc 2.5) using the calibration graph function. However, all extrapolated values must be handled with some care.

According to classification schemes, the Koc [mL/g or L/kg] value suggests that the submission item is expected to fall into the

“Very high” (Koc 0-50)

mobility class according to McCall et al. (1980 & 1981) and Swann et al. (1983), or to be

“very mobile” (Koc < 15)

according to Hollis (1991) or the FAO Mobility Classification based on Koc (FAO 2000), or to be

“highly mobile” (Koc < 10)

according to White (2009, U.S. EPA Guidance). This mobility classification was developed by the United Nations Food and Agriculture Organisation (FAO 2000) and is recommended for use in Environmental Fate and Effects Division (EFED) of the U.S. EPA Office of Pesticide Programs (OPP), which is charged with carrying out the environmental portion of pesticide assessment, when it is appropriate to describe the compound's sorption using Koc values (FAO 2000, EPA 2006).

In conclusion the submission item is not adsorbed in a relevant manner and thus is very highly mobile. Nonetheless it is unlikely that it can reach ground waters due to its ready biodegradability as evidenced by Eisner (2011, see chapter on Biodegradation in water: screening tests).

• EPA United States Environmental Protection Agency (2006). Standard Soil Mobility Classification Guidance. Memorandum from S. Bradbury to Environmental Fate and Effects Division. 23 January 2004. Environmental Fate and Effects Division. Office of Pesticide Programs. U.S. EPA.
• FAO Food & Agriculture Organization of the United Nations (2000). Appendix 2. Parameters of pesticides that influence processes in the soil. In FAO Information Division Editorial Group (ed), Pesticide Disposal Series 8. Assessing Soil Contamination. A Reference Manual. Rome (Accessed 10 July 2009).
• Hollis JM (1991). Mapping the vulnerability of aquifers and surface waters to pesticide contamination at the national/regional scale. Pesticides in Soils and Water: Current Perspectives (Walker A ed), BCPC Monograph 47:165-74.
• Klimisch HJ, Andreae M, Tillmann U (1997). A Systematic Approach for Evaluating the Quality of Experimental Toxicological and Ecotoxicological Data. DOI 10.1006/rtph.1996.1076 PMID 9056496 Regul Toxicol Pharmacol 25:1-5.
• McCall PJ, Swann RL, Laskowski DA, Unger SM, Vrona SA, Dishburger HJ (1980). Estimation of Chemical Mobility in Soil from Liquid Chromatography Retention Times. DOI 10.1007/BF01608096 PMID 7362897 Print ISSN 0007-4861 Online ISSN 1432 -0800 Bulletin of Environmental Contamination and Toxicology 24(1):190-5.
• McCall PJ, Laskowski DA, Swann RL, Dishburger HJ (1981). Measurement of sorption coefficients of organic chemicals and their use, in environmental fate analysis pages 94-109 IN Test Protocols for Environmental Fate and Movement of Toxicants: 94th annual meeting, October 21, 22, 1980, Washington, DC, U.S.A. ISBN-10 093558420X ISBN-13 978-0935584202. 330 p.
• Swann RL, Laskowski DA, McCall PJ, Vanderkuy K, Dishburger HJ (1983). A rapid Method for the Estimation of the Environmental Parameters Octanol Water Partition-Coefficient, Soil Sorption Constant, Water to Air Ratio, and Water Solubility. ISSN 0080 -181X Residue Reviews 85:17-28.
• White K (2009). Guidance for Reporting on the Environmental Fate and Transport of the Stressors of Concern in Problem Formulations for Registration Review, Registration Review Risk Assessments, Listed Species Litigation Assessments, New Chemical Risk Assessments, and Other Relevant Risk Assessment. U.S. EPA, Office of Pesticide Programs, Environmental Fate and Effects Division, published 14 December. 19 p. URL http://www.epa.gov/pesticides/science/efed/policy_guidance/team_authors/endangered_species_reregistration_workgroup/esa_reporting_fate.pdf

[LogKoc: 0.39]