Lin H T, Wong S S, Li G C
Residue Control Department, Taiwan Agricultural Chemicals and Toxic Substances Research Institute, Wufeng, ROC.
J Environ Sci Health B. 2001 Jul;36(4):409-20. doi: 10.1081/PFC-100104185.
The environmental fate and distribution of fungicide epoxiconazole were studied by a rice paddy field model ecosystem. One week before the head-sprouting stage, rice plant was treated separately once with OPUS (tradename of epoxiconazole) 12% SC 2.1 kg ha(-1) and 1.4 kg ha(-1), respectively. Soil, water and rice plant were sampled seven days intervals nine times after application. The bioconcentration factor of epoxiconazole on mosquito fish in the ecosystem was also determined, based on the amounts of epoxiconazole content both in fish and water. This was initiated one day after the fungicide treatment, and continued for four days. In addition, the residue of epoxiconazole in rice grains was analyzed after harvest. After harvest, both planted water spinach (Ipomoea aquatica Forsk) and edible amaranth (Amaranthus mangostanüs L.) were analyzed. The results showed that epoxiconazole degraded in the local environment under the experimental conditions described. The degradation equations were in accordance with the first order kinetics. The DT50 of soil, field water and rice plant were 20-69 days, 11-20 days and 14-39 days, respectively. The bioconcentration factors of epoxiconazole on mosquito fish were 12.9 and 10.6 from 2.1 kg ha(-1) and 1.4 kg ha(-1) treatment, respectively. Residues of epoxiconazole in both rice and harvest vegetables were non-detectable. This indicates that epoxiconazole applied to rice at the recommended rates and application frequencies will not accumulate on rice grain and successive cropping vegetables.
通过稻田模型生态系统研究了杀菌剂环氧菌唑的环境归宿和分布。在抽穗前期一周，分别用12% SC 2.1 kg ha(-1)和1.4 kg ha(-1)的OPUS（环氧菌唑商品名）处理水稻植株一次。施药后，每隔7天对土壤、水和水稻植株进行9次采样。根据鱼体和水中环氧菌唑的含量，还测定了该生态系统中环氧菌唑在食蚊鱼体内的生物富集系数。这在杀菌剂处理后一天开始，并持续4天。此外，收获后分析了水稻籽粒中环氧菌唑的残留量。收获后，对种植的空心菜（蕹菜）和苋菜（刺苋）进行了分析。结果表明，在所述实验条件下，环氧菌唑在当地环境中会降解。降解方程符合一级动力学。土壤、田间水和水稻植株的DT50分别为20 - 69天、11 - 20天和14 - 39天。环氧菌唑在食蚊鱼体内的生物富集系数在2.1 kg ha(-1)处理下为12.9，在1.4 kg ha(-1)处理下为10.6。水稻和收获蔬菜中均未检测到环氧菌唑残留。这表明以推荐剂量和施药频率施用于水稻的环氧菌唑不会在水稻籽粒和连作蔬菜上积累。
