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Since RAV 7NG contains as main ingredient 'diallyl 2,2'oxydiethyl dicarbonate' and experimental data are lacking for RAV 7NG, the experimental data from 'diallyl 2,2'oxydiethyl dicarbonate' were used in a read-across approach.

Justification for read-across from supporting substance RAV 7AT (diallyl 2,2'-oxydiethyl dicarbonate; CAS 142-22-3; EC 205-528-7): about 70 % of RAV 7NG (EC 700-483-4) consists of components that can be found in the commercial ADC grades known as RAV 7AT, Nouryset 200 and CR39. Merely from comparing the similar production processes of these two substances it is apparent that RAV 7AT and RAV 7NG are closely related to each other.  Finally, the physical-chemical, toxicological and ecotoxicological properties of RAV 7NG and RAV 7AT are almost equal and as a result, read across is justified.

Regarding stability in the environment an experiment was conducted with 'diallyl 2,2'oxydiethyl dicarbonate' according to OECD guideline 111 (Mullee, 2005). The abiotic hydrolysis as a function of pH was tested with a nominal concentration of 0.05 mg/L test substance. Buffer solutions of pH 4, pH 7, and pH 9 were used as well as HPLC with MS detection. With increasing pH an increase in hydrolysis rate was observed. At 25 °C a half life of over 1 year was determined, at pH 4 280 days and at pH 9 the half-life corresponds to 68.4 hours, respectively.

Diallyl-2,2`-oxydiethyl dicarbonate is considered to be readily biodegradable according to OECD criteria. The substance was tested under aerobic conditions at 21 °C according to OECD guideline 301 D / EU method C.6 for a time duration of 28 days (van Cinkel and Stroo, 1993). The initial concentration was 2 mg/L and domestic activated sludge was used as inoculum. Based on O2 consumption the substance was degraded to 86 %, thus the endogenous respiration was not reduced. The same guideline was used by RBM Instituto di Ricerche Biomediche (1994) to test the biodegradability of Diallyl-2,2`-oxydiethyl dicarbonate. The sample was observed on days 7, 14, 21, and 28 with the results of 4.4, 9.6, 47, and 73.2 % degradation, respectively. The test material did not have a significant inhibitory effect on the bacterial inoculum.

Additionally to these screening tests, one valid study result is available regarding biodegradation of 'diallyl 2,2'oxydiethyl dicarbonate in soil (Williams and Heim, 1993). The substance was tested in an aerobic fresh soil medium with a concentration of 100 mg/kg soil d.w. The test was conducted at a temperature of 25 +/- 1 °C without light for 14 days. No degradates were observed in the soil extracts. Under sterile as well as under non-sterile conditions the test substance disappeared therefore it is not possible to characterize the extent of biodegradation in this case.

The bioaccumulation potential of Diallyl-2,2`-oxydiehtyl dicarbonate was calculated with EPIWIN software BCFBAFv3.00 by US-EPA (Chemservice S.A., 2010). The aquatic bioconcentration factor (BCF) was determined to be 4.843 L/kg w.w., indicating the low bioaccumulation potential of the substance. Neither experiments regarding aquatic nor terrestrial bioaccumulation have to be conducted according to REACH regulation, due to the fact that no accumulation is expected because of the substance specific logPow of 1.54.

This low value of logPow indicates a low potential for soil adsorption of the test substance. Therefore, no experiment has to be conducted for this endpoint in accordance to REACH regulation. For completeness, again the EPIWIN computer tool (software KOCWINv2.00) was used to calculate the coefficient with the utilization of two different models (Chemservice S.A., 2010). The traditional method (based on logKow) gives a result of 16.9 L/kg and the MCI method 20.69 L/kg. The last value is used more seriously.

Concerning transport and distribution of Diallyl-2,2`-oxydiethyl dicarbonate the Henry´s Law Constant was calculated with the EPIWIN software HENRYWINv3.20. In this case, a result of 1.88 E-002 Pa*m³*mol-1 is reported (Chemservice S.A., 2010).