Residue Analysis (Pesticide/Herbicide)

Pesticide/Herbicide residue is defined by the World Health Organization as "any substance or mixture of substances in food for man or animals resulting from the use of a pesticide and includes any specified derivatives, such as degradation and conversion products, metabolites, reaction products, and impurities that are considered to be of toxicological significance." Pesticide and herbicide residue determination in water is becoming an especially imperative and challenging issue. Commonly, it involves the simultaneous trace analysis of hundreds of compounds belonging to many chemical classes.

Pesticide

Modern farming requires pesticides to control insects and other parasites in order to guarantee the needs of a growing population. Although important advances in biological control and use of natural substances in pest control have been achieved, the use of diverse classes of synthetic pesticides is still the principal means to guarantee high crop productivity. The wide use of pesticide is heavily contaminating groundwater, rivers, and lakes.

Herbicide

Herbicides in drinking water are becoming a major health concern as the conventional water treatments used by 90% of public water utilities in this country do not remove any of the herbicides that are most commonly applied in the U.S. Moreover, people that live in rural, agricultural areas are at the greatest risk of drinking herbicide contaminated water as the vast majority of them get their water from private wells which are not subject to routine testing.

How pesticide/herbicide get into drinking water

(1) Gradual accumulation in the soil where they slowly percolate down into underground water.
(2) Heavy rainfall and irrigation which wash herbicides off farmland and fall into lakes and rivers.

Pesticide/herbicide leach more quickly through coarse textured (sandy) soils that are low in organic matter and more slowly through fine textured (clay) soils and soils high in organic matter. The water solubility and adsorption characteristics of the herbicide also influence leaching. Higher solubility herbicides leach more quickly compared with herbicides with lower solubility.

The exposure to pesticide/herbicide has been associated with a wide range of adverse effects to human health, from skin irritation to several types of cancer, with the last one being the dominant and the most severe reported effect. Additionally, an elevated rate of other diseases, such as diabetes, neurodegenerative disorders like Parkinson's and Alzheimer's, reproductive disorders and birth defects, have also been associated with pesticide exposure.

To analyze the residue in water, pesticide/herbicides are initially extracted from water by different procedures: Solid Liquid Extraction (assisted or not by ultrasounds, microwaves, etc.), Liquid Liquid Extraction, or sorbent-based extraction techniques (SPE, SPME, MSPD, etc.) can be explored to extract pesticide/herbicides. A suitable cleanup or a second extraction may also be necessary, depending on the application. The procedure is simpler when samples are liquid, then GC, LC, CE are chosen for analysis, immunoassays or biosensors have also been used with success.

Alfa Chemistry is professional in water impurity analysis and we can provide accurate and reliable tests results within the time constraint. We have conducted well water analysis, drinking water quality analysis, watersheds and rivers analysis and wastewater, stormwater, runoff analysis. Please feel free to contact us if you have any concern or would like us to perform any water residue testing. Check our instruments list to see our capabilities.