Donald David B, Cessna Allan J, Sverko Ed, Glozier Nancy E
Environment Canada, Regina, Saskatchewan, Canada.
Environ Health Perspect. 2007 Aug;115(8):1183-91. doi: 10.1289/ehp.9435.
Human health anomalies have been associated with pesticide exposure for people living in rural landscapes in the northern Great Plains of North America.
The objective of this study was to investigate the occurrence of 45 pesticides in drinking water from reservoirs in this area that received water primarily from snowmelt and rainfall runoff from agricultural crop lands.
Water from 15 reservoirs was sampled frequently during the spring pesticide application period (early May to mid-August) and less frequently for the remainder of the year. Drinking water was sampled in early July. Sample extracts were analyzed for pesticide content using mass spectrometric detection.
We detected two insecticides and 27 herbicides in reservoir water. Consistent detection of a subset of 7 herbicides suggested that atmospheric deposition, either directly or in rain, was the principal pathway from fields to the reservoirs. However, the highest concentrations and number of herbicides in drinking water were associated with runoff from a localized 133-mm rainfall over 15 days toward the end of spring herbicide application. Water treatment removed from 14 to 86% of individual herbicides. Drinking water contained 3-15 herbicides (average, 6.4).
We estimated the mean annual calculated concentration of herbicides in drinking water to be 75 ng/L (2,4-dichlorophenoxy)acetic acid, 31 ng/L (2-chloro-4-methylphenoxy)acetic acid, 24 ng/L clopyralid, 11 ng/L dichlorprop, 4 ng/L dicamba, 3 ng/L mecoprop, and 1 ng/L bromoxynil. The maximum total concentration of herbicides in drinking water was 2,423 ng/L. For the seven herbicides with established drinking water guidelines, all concentrations of the individual chemicals were well below their respective guideline. However, guidelines have not been established for the majority of the herbicides found in drinking water or for mixtures of pesticides.
对于生活在北美大平原北部乡村地区的人们而言，人体健康异常与农药接触有关。
本研究的目的是调查该地区水库饮用水中45种农药的出现情况，这些水库的水主要来自农业耕地的融雪和降雨径流。
在春季农药施用期（5月初至8月中旬）频繁采集15个水库的水样，一年中的其余时间采样频率较低。7月初采集饮用水样本。使用质谱检测分析样本提取物中的农药含量。
我们在水库水中检测到两种杀虫剂和27种除草剂。7种除草剂的一致检测表明，大气沉降，无论是直接沉降还是通过降雨沉降，是从农田到水库的主要途径。然而，饮用水中除草剂的最高浓度和数量与春季除草剂施用末期15天内局部133毫米降雨产生的径流有关。水处理去除了14%至86%的各种除草剂。饮用水中含有3至15种除草剂（平均6.4种）。
我们估计饮用水中除草剂的年均计算浓度为：75纳克/升（2,4-二氯苯氧基）乙酸、31纳克/升（2-氯-4-甲基苯氧基）乙酸、24纳克/升氯吡嘧磺隆、11纳克/升二氯丙酸、4纳克/升麦草畏、3纳克/升甲草胺和1纳克/升溴苯腈。饮用水中除草剂的最大总浓度为2423纳克/升。对于有饮用水准则的7种除草剂，所有单一化学品的浓度均远低于各自的准则。然而，对于饮用水中发现的大多数除草剂或农药混合物，尚未制定准则。
