Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Environmental behaviour

According to the industrial users of 1,2,3-trichloropropane the substance is to the greatest extent emitted into the wastewater and to a minor extent into the atmosphere. The substance is soluble in water (1750 mg/L at 25 °C). Based on the measured Henry’s Law Constant of 22.8 Pa x m3 x mol-1 (Tancrède and Yanagisawa 1990) it is expected that 1,2,3-trichloropropane has a moderate volatility from the aqueous phase. Experimental data show that the half-life for stripping of 1,2,3-trichloropropane from water is between 1 and 1.5 hours (Dilling 1977, Albanese et al. 1987). A fraction of the substance dissolved in wastewater will be released to the atmosphere in wastewater treatment plants (SPI 2003). On the other hand, 1,2,3-trichloropropane may be washed out from the atmosphere by wet deposition considering the water solubility of 1,2,3-trichloropropane (WHO 2003). It is therefore expected that exchange of the substance between the aquatic and atmospheric environment occurs. The washing out of substance from the atmosphere can also lead to deposition of 1,2,3-trichloropropane onto soil. The adsorption/desorption behaviour of 1,2,3-trichloropropane was studied using silty and sandy loam (Walton et al. 1992). The Koc values resulting from the experiments were in the range of 77 to 95 indicating the low ability of the substance for adsorption. These low values show the high mobility of 1,2,3-trichloropropane in soil that may lead to the appearance of the substance in groundwater.

Modelling of environmental distribution

The predominant environmental target compartments for 1,2,3-Trichloropropane are air (approximately 85 % of the emitted mass) and water (about 11 %) if a Mackay Level I model with six compartments is used to model the environmental distribution of the substance (Mackay et al. 1993). The picture changes considerably when a Mackay Level III model is used instead: the US Environmental Protection Agency modelling program EPIWIN V3.10 Fugacity model under the assumption of evenly distributed emissions (1000 kg/hr) into air, water and soil predicts that the greatest portion of 46.7 % of 1,2,3-Trichloropropane will end up in the soil compartment, whereas 34.9 % will end up in the water compartment, 18.3 % in the air compartment and 0.12 % in the sediment (SPI 2003). The model calculated a persistence time of 335 hours. Recently, the environmental distribution of the substance was modelled with the US Environmental Protection Agency modelling program EPIWIN V4.0 Fugacity model by taking into account a more realistic emission scenario, where the greatest emission was into the water (1000 kg/hr) and less emission was into the air (100 kg/hr) and the soil (1 kg/hr) (Wormuth 2009). Under these conditions the greatest portion of 1,2,3-Trichloropropane emitted into the environment ends up in the water compartment (85.1 %) and the air compartment (13.6 %). Only minor portions may be found in the soil and sediment compartments (0.65 and 0.64 %, respectively). The persistence time calculated by the model is 334 hours and thus similar to the time calculated before.