Gu Ji-Guang, Fan Yanzhen, Gu Ji-Dong
Key Laboratory of Terrestrial Ecological Process, Shenyang Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 10015, PR China.
Chemosphere. 2003 Sep;52(9):1515-21. doi: 10.1016/S0045-6535(03)00490-9.
Persistence and degradation of the herbicides Atrazine, Cyanazine and Dicamba were measured in laboratory microcosms incubated under methanogenic condition using three soils of China. Results showed that Atrazine was more resistant to degradation than Cyanazine and Dicamba for the 300 days of incubation. Between 30% and 40% of the initially introduced chemicals were found to be not recoverable through solvent extraction of the incubated soils. Our results also indicated that the half-life of these herbicides in the three soils generally followed: Atrazine>Cyanazine>Dicamba. Biodegradation of Cyanazine and Dicamba was further substantiated by establishing enrichment cultures in which the degradation of the respective herbicides could be accelerated by the microorganisms. Our results suggest that biodegradation of xenobiotics can be established through enrichment culture transfer technique and non-extractability of chemicals should be taken into account in evaluation of chemicals' fate and risk.
在中国的三种土壤中，在产甲烷条件下培养的实验室微观世界中，测定了除草剂阿特拉津、氰草津和麦草畏的持久性和降解情况。结果表明，在300天的培养期内，阿特拉津比氰草津和麦草畏更抗降解。通过对培养土壤进行溶剂萃取发现，最初引入的化学物质中有30%至40%无法回收。我们的结果还表明，这些除草剂在三种土壤中的半衰期一般为：阿特拉津>氰草津>麦草畏。通过建立富集培养进一步证实了氰草津和麦草畏的生物降解，在富集培养中，相应除草剂的降解可被微生物加速。我们的结果表明，可通过富集培养转移技术建立异生素的生物降解，并且在评估化学物质的归宿和风险时应考虑化学物质的不可萃取性。
