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Photolysis and hydrolysis are expected to contribute significantly to the overall degradation of zinc bis dimethyldithiocarbamate (CAS No. 137-30-4) in environmental systems, as experimental data showed.

The hydrolysis half-life of the substance in sterile water was 10.4 min at pH 5, 17.67 h at pH 7 and 6.31 d at pH 9 (25°C in the dark). At pH 5 and 9 the major degradation product was carbon disulfide (CS2) while at pH 9 dimethyldithiocarbamic acid (DDC) was mainly observed.

Photodegradation in water was examined at pH 9 (25°C, continuous light cycle). The photolytic half-life of the substance was approx.. 8.7 h at pH 9. Dimethyldithiocarbamic acid (DDC) was the main intermediate transformation product, which was subsequently transformed to N,N-dimethylthioformamide and N,N-dimethylformamide. No CS2 was observed by this transformation pathway.

When applied to soil samples, the substance was found to undergo an accelerated degradation when exposed to light (half-life of 8-8.9 h in irradiated samples vs. 16.2 – 20.5 h in dark controls). Transformation products were observed in both the irradiated samples and the dark controls. The major degradation products measured were thiram, dimethyldithiocarbamic acid (DCC), N,N-dimethylformamide, CO2 and carbon disulfide.