2,2-dichloro-1,1,1-trifluoroethane

Ecotoxicological Summary

Additional information

HCFC 123 aquatic toxicity was studied in fish, aquatic in vertebrates and algae.

A short-term toxicity in Rainbow trout (S. gairdneri) was carried out (Life Science Research 1992b) at nominal concentrations of 0, 13.3, 23.5, 42.5, 74.3 and 133 mg/L HCFC 123 under semi-static conditions. The test was performed in closed system to avoid substance volatilisation. After 24, 48, and 72 hours, the surviving fish in each vessel were transferred to another vessel containing fresh dilution water. The test material was then added and the medium stirred for 3 hours.

The highest nominal concentration at which no mortalities occurred and the lowest at which there was 100% mortality were 42.5 and 133 mg/L, respectively (mean measured concentrations, 33.3 and 90.6 mg/L). The majority of deaths occurred within 24 hours at 133 mg/L (nominal) and within 48 hours at 74.3 mg/L (nominal). Treatment-related effects were seen at all exposure levels. At 74.3 and 133 mg/L (nominal), all fish were affected within 4 hours and, during the course of the test, exhibited darkened pigmentation, lethargic behavior, and loss of coordination. At 13.3, 23.5, and 42.5 mg/L (nominal), respectively, 2, 3, and 4 fish were affected at the end of the test, exhibiting either darkened pigmentation or lethargic behavior. An approximate 96 -h LC50 of 55.5 mg/l (measured concentration) was calculated.

A short-term study was conducted on water fleas (D. magna) at nominal concentrations of 3.47, 6.94, 13.9, 27.7, 55.2 mg/l HCFC 123 (Life Science Research 1992c). The test was conducted in a closed system to avoid substance volatilisation.

Exposure levels were monitored by a GC method of analysis. On 3 occasions during the test (0, 48, and 96 hours) duplicate samples were removed from the test medium at each concentration for analysis. A 48 -h EC50 of 17.9 mg/l (measured concentration, based on immobility) was established. No NOAEC could be established.

Finally, an algae study was conducted on S. capricornutum at nominal concentrations of 13.3, 42.5, 133, 425, and 1327 mg/L HCFC 123 under closed system conditions. The study results allowed calculating a 96 -h EC50 of 96.6 mg/l and 67.8 mg/l for growth rate and biomass, respectively.

Conclusion on classification

Based on all available ecotoxicological data for daphnids, fish and algae,2,2 -dichloro-1,1,1 -trifluoroethane could meet the criteria for classification as R52/53 according to Directive 67/548/EEC and as Aquatic chronic toxicity category 3 under EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 (48 h-EC50 in D.magna is 17.3 mg/l and the substance is not readily biodegradable). However, even though HCFC 123 results not readily biodegradable, the low persistence in aqueous compartment is assured by the high volatility of the substance (see section 5.4.4). Due to the low persistence of HCFC 123 in water, no chronic toxicity to aquatic biota is expected to occur and the classification for aquatic chronic toxicity is not deemed necessary.

The substance is classified as dangerous for the ozone layer (R59) according to Directive 67/548/EEC and hazardous to the ozone layer (H420) according to Regulation (EC) No. 1272/2008.