An extraction method and residues of benzimidazole fungicides in soybean sprouts

콩나물중 benzimidazole계 농약의 추출방법과 잔류성

An analytical method was approached to determine the residues of benzimidazole fungicides in soybean sprouts and was compared with traditional solvent-based method of extraction, solid phase extraction(SPE) and matrix solid phase dispersion(MSPD). The recoveries of carbendazim for liquid-liquid extraction (LLE), SPE and MSPD in soybean sprouts were $69.25{\sim}79.16$, $79.99{\sim}90.42$ and $92.40{\sim}98.48%$, respectively. The recoveries of thiabendazole for LLE, SPE and MSPD in soybean sprouts were $64.86{\sim}83.26$, $79.12{\sim}94.04$ and $65.44{\sim}73.92%$, respectively. The residues of carbendazim by elapsed time under our cultivated soybean sprouts program found $0.10{\sim}0.25$ mg/kg after 5 days and trace concentration of carbendazim was detected after 7 days. Of the 448 samples analyzed, less than 1.5% had residues of carbendazim ranged from 0.05 to 0.37 mg/kg.

콩나물중 잔류농약의 효율적인 분석법을 확립하기 위하여 carbendazim과 thiabendazole을 0.1, 0.3, 0.5 mg/kg 씩 첨가하여 농약성분의 추출방법을 비교하였고, 잔류성을 평가하기 위하여 thiophanate-methyl 1.0, 2.0 g/L 용액에 수침시킨 콩으로 콩나물을 재배하면서 매일 잔류량을 조사하였으며, 또한 시중에 유통되는 콩나물중 benzimidazole계 농약의 잔류실태 조사를 실시하였다. 추출방법에 따라 carbendazim의 회수율은 LLE $69.25{\sim}79.16%$, SPE $79.99{\sim}90.42%$, MSPD $92.40{\sim}98.48%$이었으며, thiabendazole의 회수율은 LLE $64.86{\sim}83.26%$, SPE $79.12{\sim}94.04%$, MSPD $65.44{\sim}73.92%$로 고체상 추출방법이 우수하였다. 또 재배기간별 carbendazim 잔류량은 콩나물 출하적기인 재배 5일 째 $0.10{\sim}0.25$ mg/kg이었으며, 출하적기를 넘긴 7일째에도 농약이 잔류되었다. 유통 콩나물 448건을 검사한 결과 6건에서 carbendazim이 검출되었고 검출량은 3건에서 0.1 mg/kg 미만이었으나 3건에서는 0.1 mg/kg을 초과하여 최대 0.37 mg/kg까지 검출되었다.