Pesticide residues increasingly found in Estonia's farmland soils

Estonia's state Environment Agency (Keskkonnaagentuur) says pesticide residues are being found increasingly often in the country's arable soils. Agency adviser Martin Maddison said that while concentrations remain low and do not exceed limit values, detections have been rising year after year.

Maddison warned that pesticides in use could eventually begin accumulating in the soil, potentially affecting soil organisms in the future. The agency runs long-term soil monitoring to track changes early so that measures can be taken to restore soil health where needed.

Overall condition still generally good

Most monitored indicators still point to healthy soil conditions. Soil pH remains suitable for plant growth, nutrient levels are sufficient, and heavy metal concentrations stay below target values. No significant changes were found in the thickness of the humus horizon, the nutrient-rich upper soil layer essential for plant growth.

However, long-term monitoring data combined with 2025 results point to several trends requiring attention: declining organic carbon levels, phosphorus accumulation, soil compaction, and the growing presence of pesticide residues.

Heavy rainfall took a toll

Last summer was exceptionally rainy in Estonia, affecting the naturally moist, clay-like gley soils examined in the monitoring program. During heavy rain, soil pores — which can make up as much as 60 percent of total soil volume — quickly fill with water, depriving soil organisms of oxygen and slowing biological activity.

As a result, plants can struggle to absorb nutrients even in otherwise fertile soil, sometimes dying before they can be harvested. Maddison also pointed to a more visible consequence of the heavy rains: crops being flattened in grain fields, destroying the harvest.