Abstract
Promoting the organic farming, much of the plant extracts used for controlling pests and fungi have been imported from China, India and Myanmar. But, it is so worrisome that aquatic animals such as muddy loach inhabiting in paddy field and common carps in river exposed to the pests and fungi likely be harmed. This study was conducted in order to evaluate the risks of aquatic animals influenced by the three plant extracts, i.e. Sophora flavescens, Azadirachta indica and Derris elliptica. The toxicities of common carp (Cyprinus Carpio), muddy loach (Misgurnus anguillicaudatus) and PEC (Predicted environmental concentration) exposed to the three plant extracts were estimated by the typical spray volume method. Risks were determined by the toxicity value as 48-hr $LC_{50}$ (Lethal concentration, median) or NOEC (No observed effect concentration) into PEC. 48-hr $LC_{50}$ of Common carp and NOEC by Sophora flavescens extracts was 7.9 and 6.2 mg/L, 26.8 and 21.8 mg/L by Azadirachta indica extracts and 47.0 and < 24.0 mg/L by Derris elliptica extracts, respectively. 48-hr $LC_{50}$ of Muddy loach and NOEC by Sophora flavescens extracts was 16.9 and 10.0 mg/L, 35.6 and 30.0 mg/L by Azadirachta indica extracts, and 73.9 and < 40 mg/L by Derris elliptica extracts, respectively. Therefore, acute toxicities of the three plant extracts for aquatic animals were proved to be very low level. PEC of Sophora flavescens extracts in paddy, drainage and river water was 68.0~3.0, 11.33~0.50 and 3.0~0.0018 mg/L, respectively. TER of Sophora flavescens extracts in the three water was 0.2~5.6, 1.5~33.8 and 2.6~4388.9, respectively. PEC of Azadirachta indica extracts in paddy, drainage and river water was 90.9~1.2, 15.2~0.2 and 4.8~0.00075 mg/L, respectively. TER of Azadirachta indica extracts in the three water was 0.4~29.7, 2.3~178.0 and 4.5~35733.3, respectively. PEC of Derris elliptica extracts in river water was 0.0063 mg/L. TER of Derris elliptica extracts in river water was 5222~15667.
최근 유기농업자재의 주요 원재료인 고삼, 님, 데리스 등의 식물추출물은 중국, 미얀마, 인도 등 외국에서 수입하여 해충방제용으로 많이 사용하고 있는데, 본 논문은 이들 세가지 식물추출물에 대한 독성과 위해성을 평가하 여 유기농업자재의 관리와 환경생물보호에 활용하고자 하였다. 잉어 48시간 반수치사농도와 무영향농도는 고삼추출물은 7.9, 6.2 mg/L, 님추출물은 26.8, 21.8 mg/L, 데리스추출물은 47.0, < 24.0 mg/L으로 독성이 낮았다. 미꾸리 48시간 반수치사농도와 무영향농도는 고삼추출물은 16.9, 10.0 mg/L, 님추출물은 35.6, 30.0 mg/L, 데리스추출물은 73.9, < 40mg/L로 독성이 낮은 수준이었다. 고삼추출물 자재의 논, 배수로 및 강에서의 물중 추정농도는 각각 68.0~3.0, 11.33~0.50 3.0~0.0018 mg/L이었고, 독성노출비는 논, 배수로 및 강물에서 각각 0.2~5.6, 1.5~33.8, 2.6~4388.9이었다. 논이나 배수로에서의 미꾸리에 대한 위해성과 강에서의 잉어에 대한 위해성은 낮은 것으로 평가되었다. 님추출물의 논물, 배수로물 및 강물 중 추정농도는 각각 90.9~1.2, 15.2~0.2, 4.8~0.00075 mg/L이었고 독성노출비는 각각 0.4~29.7, 2.3~178.0, 4.5~35733.3이었다. 논에 사용하는 님추출물 중 독성노출비로 평가하였을 때 미꾸리에 위해가능성이 있는 자재가 있었으나 사용량이 많은 것이 원인으로 추가적인 연구가 필요하였고, 배수로나 하천에서는 어류에 대한 위해성이 낮았다. 데리스추출물 5종의 경우 독성노출비가 5222~15667로서 위해성이 매우 낮았다.
