Thiophanate-methyl

PBT assessment

PBT assessment: overall result

Reference

Name:

Thiophanate-methyl

Type of composition:

legal entity composition of the substance

State / form:

solid: particulate/powder

Reference substance:

Thiophanate-methyl

PBT status:

the substance is not PBT / vPvB

Justification:

Persistence:

Stability: The test item was shown to be stable to hydrolysis at ambient temperature (22 °C) and pH-values (5 – 7). The half-life of the test item at 25 °C was determined to be 867, 36 and 0.7 days at pH 5, 7 and 9, respectively. Under environmental conditions (pH 7 and 12 °C) the test item's hydrolysis constant was calculated to be 0.00028356 h-1 and the DT₅₀ to be 2444.44 h or 101.85 d.

 

Biodegradation: A study on (aerobic) ready biodegradability revealed that the substance is not biodegradable. In further biodegradation simulation tests, it was shown that the test item degraded extensively in the water phase (with DT₅₀ ranging from 0.64 to 2.2 days) and sediment phase (with DT₅₀ ranging from 1.6 days (river) to 3.5 days (pond)) to producing the principal transformation product Carbendazin. The major observed degradation product in the simulation studies was Carbendazim. Carbendazim (CAS 10605-21-7) is not inherently biodegradable in a study according to OECD 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test) and not a PBT/vPvB substance. The substance has been assessed to fulfil the criteria for not P, not B and not T; therefore, it is not classified as a PBT/vPvB substance.

 

Bioaccumulation:

It can be concluded that the substance does not meet criteria for B / vB substance. The partition coefficient octanol/water of the test item was experimentally determined to be 1.4. This value is below the set threshold, therefore, the test item is not considered to have bioaccumulation potential and thus is not considered to be B/vB.

 

Toxicity:

The substance is not classified for mutagenicity Cat.1A or 1B or carcinogenicity Cat.1A or 1B according to Regulation EC No 1272/2008. The substance is not classified for STOT RE Cat. 1 or 2 according Regulation EC No 1272/2008. The long-term toxicity to Daphnia magna revealed a reproduction NOEC of 0.161 mg/L. Currently available data make it appear as unlikely that the substance exhibits long-term toxic effects in the (aquatic) environment. Based on these grounds the screening assignment is "not T".

 

Conclusion:

Based on the available data, the test substance is not considered to be PBT/vPvB.