Pesticides and Their Metabolites in Drinking Water
Analysing water or drinking water for pesticide residues requires other methods than the detection of pesticides in fruit or vegetables or even in processed foods. ifp Institut für Produktqualität has established a special drinking water multimethod for the sensitive determination of a total of 464 agents and metabolites (including phenoxy carboxylic acid / acidic herbicides). After special extraction, determination is performed by means of HPLC-MS/MS and GC-MS/MS.
In addition, we offer individual analyses for substances not covered by the multimethod, e.g.:
- chlorate and perchlorate
- glyphosate and AMPA
How do pesticides get into the water?
In conventional agriculture pesticides are extensively used on crops in order to guarantee the crop yield. In organic farming, by contrast, the use of chemical/synthetic pesticides is forbidden. However, it is hardly possible to keep both types of crop separate from each other. Driftage to neighbouring crops or waters due to weather conditions cannot be excluded. In addition, even when used appropriately in conventional farming, residues may trickle into the groundwater and hence into the drinking water. In this, factors such as the soil conditions and the chemical properties of the respective pesticide play a part. Apart from the pesticides themselves, their in part toxic metabolites may also contaminate the water.
Maximum allowed concentration for pesticide residues in drinking water
In Europe the quality of water intended for human consumption is defined in Council Directive 98/83/EC and translated into German national law by the German Drinking Water Ordinance (TrinkwV 2001). According to the German Drinking Water Ordinance, no single pesticide agent and no relevant metabolic or reactive product may exceed the limit value specified in Annex 2 Part 1 of 0.1 microgram per litre (µg/L). Furthermore, in the event of multiple residues, the sum of the individual substances must not exceed the maximum concentration of 0.5 µg/L. A significantly lower limit value (of 0.03 µg/L) applies to the persistent insecticides Aldrin, Dieldrin, Heptachlor and its metabolite heptachlorepoxide.