Tagun Rungnapa, Boxall Alistair B A
Biology Department, Chiang Mai Rajabhat University, Chiang Mai, 50300, Thailand.
Environment Department, University of York, Heslington, York, YO10 5DD, UK.
Bull Environ Contam Toxicol. 2018 Apr;100(4):516-523. doi: 10.1007/s00128-018-2291-y. Epub 2018 Feb 13.
In the field, aquatic organisms are exposed to multiple contaminants rather than to single compounds. It is therefore important to understand the toxic interactions of co-occurring substances in the environment. The aim of the study was to assess the effects of individual herbicides (atrazine, 2,4-D, alachlor and paraquat) that are commonly used in Thailand and their mixtures on Lemna minor. Plants were exposed to individual and binary mixtures for 7 days and the effects on plant growth rate were assesed based on frond area measurements. Experimental observations of mixture toxicity were compared with predictions based on single herbicide exposure data using concentration addition and independent action models. The single compound studies showed that paraquat and alachlor were most toxic to L. minor, followed by atrazine and then 2,4-D. For the mixtures, atrazine with 2,4-D appeared to act antagonistically, whereas alachlor and paraquat showed synergism.
在野外，水生生物接触的是多种污染物而非单一化合物。因此，了解环境中共存物质的毒性相互作用非常重要。本研究的目的是评估泰国常用的几种除草剂（阿特拉津、2,4-滴、甲草胺和百草枯）及其混合物对浮萍的影响。将植物暴露于单一除草剂和二元混合物中7天，并根据叶面积测量评估对植物生长速率的影响。使用浓度相加和独立作用模型，将混合物毒性的实验观察结果与基于单一除草剂暴露数据的预测结果进行比较。单一化合物研究表明，百草枯和甲草胺对浮萍毒性最大，其次是阿特拉津，然后是2,4-滴。对于混合物，阿特拉津与2,4-滴似乎表现出拮抗作用，而甲草胺和百草枯则表现出协同作用。
