Denmark | New pesticide found in groundwater

In connection with the groundwater monitoring in 2023, the Danish Environmental Protection Agency has found the substance DMSA in the groundwater.

DMSA is a breakdown product from the active substance cyazofamide. Cyazofamid has been approved and used to control fungal diseases in potatoes in the period 2004 to 2023.

Analyzes have been carried out on groundwater samples from 247 intakes in groundwater boreholes, where DMSA has been found in eight of the intakes. This corresponds to 3.2 percent of intakes. The highest detected concentration is 0.49 µg/L. The finds are located in Central and South Jutland.

All findings are exceedances of the applicable quality requirement, which for DMSA is 0.01 µg/L. This quality criterion has been tightened in relation to the general requirement value for pesticides of 0.10 µg/L. The stricter quality criterion is set on the basis of a precautionary principle, as DTU cannot rule out in a health assessment for the substance that DMSA may cause damage to heritage plants, and there is also no data available for an actual risk assessment for health.