Kolpin D W, Thurman E M, Linhart S M
U.S. Geological Survey, 400 S. Clinton St., Box 1230, Iowa City, Iowa 52244, USA.
Arch Environ Contam Toxicol. 1998 Oct;35(3):385-90. doi: 10.1007/s002449900392.
Numerous studies are being conducted to investigate the occurrence, fate, and effects on human health and the environment from the extensive worldwide use of herbicides to control weeds. Few studies, however, are considering the degradates of these herbicides in their investigations. Our study of herbicides in aquifers across Iowa found herbicide degradates to be prevalent in ground water, being detected in about 75% of the wells sampled. With the exception of atrazine, the frequencies of detection in ground water for a given herbicide increased multifold when its degradates were considered. Furthermore, a majority of the measured concentration for a given herbicide was in the form of its degradates-even for a relatively persistent compound such as atrazine. For this study, degradates comprised from 60 to over 99% of a herbicide's measured concentration. Because herbicide degradates can have similar acute and chronic toxicity as their parent compounds, these compounds have environmental significance as well as providing a more complete understanding of the fate and transport of a given herbicide. Thus, it is essential that degradates are included in any type of herbicide investigation.
目前正在进行大量研究，以调查在全球范围内广泛使用除草剂控制杂草所产生的发生情况、归宿及其对人类健康和环境的影响。然而，很少有研究在调查中考虑这些除草剂的降解产物。我们对爱荷华州各地含水层中的除草剂进行的研究发现，除草剂降解产物在地下水中普遍存在，在约75%的采样井中都有检测到。除莠去津外，当考虑其降解产物时，特定除草剂在地下水中的检测频率会增加数倍。此外，即使对于像莠去津这样相对持久的化合物，特定除草剂的大多数测量浓度也是以其降解产物的形式存在。在本研究中，降解产物占除草剂测量浓度的60%至99%以上。由于除草剂降解产物可能具有与其母体化合物相似的急性和慢性毒性，这些化合物不仅具有环境意义，还能更全面地了解特定除草剂的归宿和迁移。因此，在任何类型的除草剂调查中都必须纳入降解产物。
