Behavior of the herbicide metolachlor in carps

제초제 metolachlor의 잉어체내 행적

  • Kyung, Kee-Sung (Department of Crop Protection, National Institute of Agricultural Science and Technology, RDA) ;
  • Kim, Jin-Wha (Department of Crop Protection, National Institute of Agricultural Science and Technology, RDA) ;
  • Lee, Byung-Moo (Department of Crop Protection, National Institute of Agricultural Science and Technology, RDA) ;
  • Oh, Byung-Youl (Department of Crop Protection, National Institute of Agricultural Science and Technology, RDA) ;
  • Jeong, Young-Ho (Department of Crop Protection, National Institute of Agricultural Science and Technology, RDA) ;
  • Lee, Jae-Koo (Department of Agricultural Chemistry, Chungbuk National University)
  • 경기성 (농업과학기술원 작물보호부 농약안전성과) ;
  • 김진화 (농업과학기술원 작물보호부 농약안전성과) ;
  • 이병무 (농업과학기술원 작물보호부 농약안전성과) ;
  • 오병렬 (농업과학기술원 작물보호부 농약안전성과) ;
  • 정영호 (농업과학기술원 작물보호부 농약안전성과) ;
  • 이재구 (충북대학교 농과대학 농화학과)
  • Published : 1999.08.25

Abstract

In order to investigate the behavior of the herbicide metolachlor [2-chloro-6'-ethyl-N-(2-methoxy-1-methylethyl)aceto-O-toluidide] in fish, carps (Cyprinus carpio L.) were exposed to the herbicide at $LC_{10}$(1.93 mg/L) for 4 days. Metolachlor dissolved in water was absorbed rapidly into carps to mark the maximum concentration 6 hours after exposure. The amounts of the $^{14}C$-metolachlor and its metabolites absorbed in gall were much higher than those in the other parts, strongly suggesting that biliary excretion involving enterohepatic recirculation could be an important route for the elimination of metolachlor. The $^{14}C$-radioactivity distributed into aqueous phase fraction in test water and in carp extract was increased in time-dependent manner. Extraction rate of $^{14}C$ absorbed in carp tissues was decreased remarkably up to 6 hours after exposure, suggesting that the possible polar metabolites of metolachlor were transformed into the conjugates to form non-extractable bound residues.

제초제 metolachlor [2-chloro-6'-ethyl-N-(2-methoxy-1-methylethyl)aceto-O-toluidid]의 잉어체내 행적을 구명하기 위하여 $LC_{10}$(1.93 mg/L)으로 metolachlor를 처리한 시험수에 잉어를 경시적으로 노출시켰다. 수중의 metolachlor는 잉어 체내에 신속히 흡수 이행되어 노출 후 6시간에 최대 흡수량을 나타내었으며, 잉어에 흡수 이행된 metolachlor의 주요 배설경로는 담도이었다. 또한 잉어 체내에 흡수 이행된 방사능의 추출율이 처리 후 6시간까지 현저히 감소하여 잉어 체내에서 생성된 극성 대사산물이 잉어체내에서 접합체를 형성한 후추출이 불가한 결합잔류물을 형성하였음을 시사하였다. 시험수와 잉어 추출액중 방사능이 수상으로 분배된 양이 각각 처리후 12시간과 6시간에 가장 높았고 그 양도 각각 총처리 방사능의 약 14% 및 12%로써 metolachlor가 잉어 체내에서 신속히 대사될 가능성을 시사하였다.

Keywords