Ziram

Endpoint summary

Additional information

Studies investigating the short-term toxicity of zinc bis dimethyldithiocarbamate (CAS No. 137-30-4) are available for all terrestrial trophic levels and long-term toxicity results are available for vertebrates and invertebrates.  

Results from the short-term toxicity studies on terrestrial organisms revealed acute toxic effects toward earthworms with an LC50 (14 d) of 140 mg a.i./kg dw soil. Furthermore, effects to bird species were observed after acute oral and dietary exposure (LD50 = 97 mg a.i./kg bw and LC50 = 5156 ppm a.i., respectively). The substance showed no effects on survival of honeybees after 48 hours exposure via oral and contact routes (LD50 (48 h) > 100 µg/bee). The substance does not cause adverse effects to plants growth or condition up to the highest concentration tested (9 kg/ha, recalculated to 9.192 mg a.i./kg soil dw) as Tier 1 studies with Ziram WG 76 showed. Furthermore, no short-term toxic effects were caused by the substance to soil microorganisms up to the highest tested concentration of 40.5 mg test item/kg soil dw (LC50 (28 d) > 40.5 mg test item/kg soil dw). 

Chronic tests showed no effects on the earthworm Eisenia fetida (NOEC (55 d) ≥ 10.1 mg a.i./kg soil dw, OECD 222) or effects on mortality and reproduction of Folsomia candida and Hypoaspis aculeifer (NOEC≥17.1 mg a.i./kg soil dw, OECD 232 and 226).The soil microflora activity resulted into an LC50 (28 d) > 40.5 mg test item/kg soil dw (nominal) and the birds reproduction study revealed a NOEC (20 wk) of 500 mg a.i./kg diet. Chronic toxicity is not expected in terrestrial organisms exposed to zinc bis dimethyldithiocarbamate due to its rapid biodegradation in the soil compartment with half-lives of < 2 days (aerobic) and 14 days (anaerobic).