Selecting pesticides for inclusion in drinking water quality guidelines on the basis of detection probability and ranking

Abstract

Pesticides released into the environment may pose both ecological and human health risks. Governments set the regulations and guidelines for the allowable levels of active components of pesticides in various exposure sources, including drinking water. Several pesticide risk indicators have been developed using various methodologies, but such indicators are seldom used for the selection of pesticides to be included in national regulations and guidelines. The aim of the current study was to use risk indicators for the selection of pesticides to be included in regulations and guidelines. Twenty-four risk indicators were created, and a detection rate was defined to judge which indicators were the best for selection. The combination of two indicators (local sales of a pesticide for the purposes of either rice farming or other farming, divided by the guideline value and annual precipitation, and amended with the scores from the physical and chemical properties of the pesticide) gave the highest detection rates. In this case study, this procedure was used to evaluate 134 pesticides that are currently unregulated in the Japanese Drinking Water Quality Guidelines, from which 44 were selected as pesticides to be added to the primary group in the guidelines. The detection probability of the 44 pesticides was more than 72%. Among the 102 pesticides currently in the primary group, 17 were selected for withdrawal from the group.

Pesticide Determination in Water Samples from a Rural Area by Multi-Target Method Applying Liquid Chromatography-Tandem Mass Spectrometry

“…Considering the EU guidelines for water quality standards for consumption, the maximum residue limit (MRL) for the total active ingredients is of 0.50 µg L -1 of pesticides, including metabolite degradations and reaction products. 25,26 With regards to this, at least 58% of the samples analyzed in our study have a total concentration of pesticides higher than the recommended. However, it is important to highlight that only 12 pesticides of those 26 confirmed compounds in the screening stage were quantified, which means that the total concentration of pesticides can be even higher.…”

“…This fact emphasizes the need to review the matter of pesticide monitoring in the national legislation. 25,26 Despite the discrepancy between national and international regulations, accordingly to Avelhan and Zylbersztajn, 27 Brazil has the most advanced and restricted law concerning environmental protection, but its enforcement has several loopholes.…”

Farmers’ Criteria for Pesticide Selection and Use in the Pest Control Process

“…Pesticides are a vital component and an integral part of modern agriculture [1,2]. These chemicals quickly gained great popularity as an efficient, labor-saving, and economic tool in pest management in most agricultural sectors [3].…”

Presence of the β-triketone herbicide tefuryltrione in drinking water sources and its degradation product in drinking waters

“…Rice-farming herbicides easily enter natural river waters at higher rates than other pesticides used in upland farming because they are applied to paddy fields where a large amount of water is irrigated, ponded, and drained during the rice-farming seasons (Narita et al, 2014). According to a national survey of drinking and source water quality (Matsui, 2016), rice-farming herbicides such as molinate and pretilachlor are detected more frequently at high concentrations than other pesticides.…”