Removal of Malathion Residues from Fruits and Vegetables by Washing Processes

과일채소중 말라티온 잔류분(殘溜分)의 세척효과

In order to determine the removal efficiency of pesticide residues in fruits and vegetables by washing processes, samples of lettuce, young Chinese radish, Chinese cabbage, green red pepper, strawberry and grape were artificially contaminated with malathion and washed according to the household practices. After three times washings with water, the remaining ratios of malathion residues in grape, green red pepper, strawberry, young Chinese radish, lettuce and Chinese cabbage were 9.7%, 25.2%, 28.0%, 29.7%, 38.9% and 57.5%, respectively. After washing with detergent solution followed by two times rinsing with water, the remaining ratios of malathion residues in the same food samples were 1.6%, 8.3%, 15.8%, 24.8%, 27.2% and 45.9%, respectively. The removal efficiency of malathion by detergent washing was significantly higher than the water washings only. The removal ratio of malathion residues was the highest in the first washing and the ratio fell greatly in the following washings. The removal efficiency was not quite different in the temperature range of $5-35^{\circ}C$ of the washing solution, but the efficiency at $100^{\circ}C$ was 2-3 times higher than other temperature ranges.

과일과 채소에 오염(汚染)된 잔류농약(殘留農藥)의 세척(洗滌)효율을 알기 위하여 상추, 열무, 풋고추, 딸기, 포도에 말라티온을 인위적으로 처리하고 가정(家庭)에서의 세척(洗滌)방법에 준하여 실험한 결과는 다음과 같다. 물에 의하여 3회 세척한 후의 말라티온 잔류율(殘留率)은 포도 9.7%, 풋고추 25.2%, 딸기 28.0%, 열무 29.7%, 상추 38.9%, 배추57.5%로서 배추에서 세척(洗滌)효율이 가장 낮았다. 연성세제(軟性洗劑)로 1 회 세척하고 물로 2 회 수세(水洗)한 후의 말라티온 잔류율(殘留率)은 포도 1.6%, 풋고추 8.3%, 열무 15.8%, 딸기 24.8%, 상추 27.2%, 배추 45.9%로서 세제(洗劑)에 의한 효과가 현저히 증가하였다. 부착(附着)된 말라티온은 1 회 세척에서 가장 많이 제거되었고 그후의 세척에서는 별로 제거되지 않았다. 수온(水溫)이 $5{\sim}35^{\circ}C$ 범위에서는 세제(洗劑) 효율에 큰 차이가 없었고, $100^{\circ}C$에서는 세척효율이 이보다 $2{\sim}3$배 더 높았다.