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Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

No short-term or long-term toxicity on three toxonomic groups of three trophic levels in the aquatic compartment of MBTS was observed up to its water solubility (i.e. <0.05 mg/L).

Thus, no hazard could be identified.

Additional information

The short-term toxicity and long-term toxicity of MBTS was tested on three trophic levels. The concentrations tested were always higher than its water solubility (i.e. <0.05 mg/L) and precipitation in test vessels were often reported. No acute ot chronic toxic effect of MBTS on three taxonomic groups of three trophic levels was observed up to water solubility.

For the assessment of microorganisms in biological treatment plants, an EC50 > 10000 mg/l was observed after 3 hours exposure at a pH 7.5 - 8.3 and temperature of 20.5 - 22.4 °C (Bayer AG, 1990). To the nitrification inhibition by 2,2'-disulfanediylbis(1,3-benzothiazole) an EC75 of 38 mg/L during a 2 - 4 h incubation period was obtained. (Tomlinson, Boon, and Trotman, 1966). As the most sensitive value, the effective concentration on nitrification inhibition is used for further assessment. MBTS is hydrolytically stable (Hasson & Agrup, 1993). The transformation of MBTS to MBT (CAS: 149-30-4) requires reductive condition and the formation of benzothiazole (BT) and benzothiazolone (BTon) requires high temperature (>60°C) and high pH (>9); and hence these potential metabolites of MBTS are considered to be not relevant in the ecotoxicity studies of MBTS