Risk analysis for groundwater intakes based on the example of neonicotinoids.

Area of Science:

• Environmental Chemistry
• Ecotoxicology
• Water Quality Management

Background:

• Neonicotinoids are widely used, broad-spectrum insecticides dominating the global market.
• Their widespread environmental distribution necessitates understanding their impact on aquatic ecosystems.
• Groundwater contamination by neonicotinoids is a significant global concern.

Purpose of the Study:

• To propose a novel risk analysis approach for groundwater contamination by emerging contaminants.
• To evaluate the risk posed by four neonicotinoids (acetamiprid, clothianidin, thiamethoxam, imidacloprid) to groundwater quality.
• To assess the implications for human and ecological health based on drinking water standards.

Main Methods:

• Laboratory-based column experiments simulating pesticide migration in soil.
• Dynamic method applied to assess contaminant transport under realistic conditions.
• Risk analysis framework integrating pesticide properties and groundwater intake scenarios.

Main Results:

• Acetamiprid and thiamethoxam use poses an acceptable risk to groundwater quality for drinking and food purposes.
• Clothianidin and imidacloprid present a significant risk of groundwater contamination.
• Even at manufacturer-recommended concentrations, clothianidin and imidacloprid levels in groundwater intakes can exceed safe drinking water limits (<0.1 μg/L) by several to hundreds of times.

Conclusions:

• Risk assessment is crucial for managing neonicotinoid contamination in water resources.
• Clothianidin and imidacloprid require stricter regulation and management to prevent widespread groundwater pollution.
• The proposed risk analysis method effectively identifies pesticides posing unacceptable threats to drinking water safety.