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Experimental data from tests investigating the fate of KDDC in the environment were not conducted since studies from a similar analogue are considered to be suitable for this purpose. Conclusions regarding this section have been drawn based on studies performed on SDDC (Sodium dimethyldithiocarbamate, CAS No. 128-04-1). Both KDDC and SDDC represent salts of dimethyl dithiocarbamic acid (DDC) that are capable of dissociating into the respective ions (K+and Na+) when exposed to water. The physico-chemical parameters of both substances are listed in the table below.

Table 1. Physico-chemical parameters of KDDC and SDDC




CAS no.




potassium dimethyldithiocarbamate

sodium dimethyldithiocarbamate

Molecular weight

159.3 g/mol

143.2 g/mol

Molecular formula



Melting point

Partial melting from 81.5 to 85.0°C followed by slow decomposition

Decomposition at
≥ 253°C

Relative density at 20°C



Vapour pressure at 25°C


< 2×10–4Pa

Log Pow at 20°C

read across to SDDC

pH 5: = –3.2
pH 7: < –2.28
pH 9: < –2.33

Water solubility

read across to SDDC

37.4 - 40% (w/w)
pH 10.5

Considering the similarities in molecular structure and characteristics of these two substances, an analogue approach from SDDC to KDDC is justified.

KDDC exhibits a low vapour pressure and low volatility. Therefore, photodegradation is not an important degradation pathway. Nevertheless, if emitted into the air, KDDC will be rapidly photodegraded (estimated half-life = 4.6 hours for indirect photodegradation, OH-radicals). Furthermore, based on the available information from the analogue substance, KDDC is expected to undergo rapid photolysis in water as well (half-life = 19 hours). Once released into the water phase, hydrolysis might contribute significantly to the degradation of this substance, especially under acidic and neutral conditions (half-lives of 0.6 h and 41.6 hours at pH 4 and 7, respectively).

KDDC is considered to be readily biodegradable and therefore, additional tests on biodegradation in water, sediment and soil are not deemed necessary. Based on the available information, this substance is not expected to persist in the environment.

The estimated Henry’s Law constant (<6.3×10-08Pa m3/mol at 20 °C) indicates that KDDC will not tend to evaporate from the water surface. This substance has no potential for adsorption to solid particles (log Koc = -0.12) and based on its log Kow (<0) and estimated BCF (0.84), bioaccumulation in biota is not expected.