Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Reliable studies (Klimisch score 1 or 2) that can be used in the assessment of the bioaccumulation potential of thiourea are not available. Nonetheless, a new bioaccumulation study in aquatic species does not need to be conducted, as in accordance with column 2 of REACH Annex IX the substance has a low potential for bioaccumulation (log octanol water partition coefficient less than 3).

This statement is further supported by two Klimisch 3 studies conducted by Geyer et al. (1984) and Freitag et al. (1985):

- Geyer et al. (1985) exposed algae (Chlorella) to 14C-labelled thiourea for at least 24 h at room temperature (20-25 °C). The bioaccumulation factor for the alga Chlorella was determined to be 54.

- Freitag et al. (1985) experimentally determined the bioconcentration of thiourea in the fish Leuciscus idus melanotus after 3 days of exposure to be < 10.

Due to the information and results presented above, it can be concluded that thiourea does not have a significant potential for bioaccumulation. Following the precautionary principle the higher BCF value of 54 is used as key value in the risk assessment.

Data on terrestrial bioaccumulation are not available.