폐금속광산 주변 논토양 및 벼작물의 비소함량과 계절적 변화

Contents and Seasonal Variations of Arsenic in Paddy Soils and Rice Crops around the Abandoned Metal Mines

이 연구는 국내 휴폐금속광산 주변의 논토양과 식물(벼)의 비소 오염과 계절적 변화를 고찰하고, 토양과 식물의 유 기적 관계규명을 위해 토양시료를 왕수, 1 M MgCl2, 0.01 M CaCl2 및 0.05 M EDTA 등 다양한 추출제로 전처리하 여 비소를 분석하였다. 화학분해 방법에 따른 함량 변화는 통계적으로 유의한 양의 상관관계를 보이며(p<0.01), 1 M MgCl2>0.01 M CaCl2>0.05 M EDTA 순으로 나타났다. 벼줄기의 생물학적 농축계수는 산화환경보다 환원환경에서 높았으며, 백미시료에서는 농축계수가 0.02로 낮게 나타났다. 농가의 1일 평균 쌀소비량인 315 g을 적용하여 세계보 건기구의 미량원소 1일 섭취 최대허용량과 비교한 결과 농가에서는 65%의 높은 섭취량을 보여, 이들 쌀 소비에 의한 비소의 인체섭취도에 중요한 역할을 하고 있음을 확인하였다.

The objective of this study is to investigate the contents and seasonal variation of arsenic in soils and crop plant(rice) in paddy fields around the abandoned metal mines in Korea. The soils were extracted by various methods including aqua regia, 1 M MgCl2, 0.01 M CaCl2 and 0.05 M EDTA to evaluate the relationships between soils and crop plants(rice). According to correlation analysis, statistically significant correlation with the four methods( p<0.01) were found in soils extracted by various chemical solutions and arsenic contents in soils were decreased in the order of 1M MgCl2 > 0.01M CaCl2 > 0.05 M EDTA. Biological accumulation coefficients(BACs) of rice stalks were higher than those of rice grain, and the coefficients under reducing(August) environment were higher than those under oxidizing conditions(October). Assuming the rice consumption of 315 g/day by farm households in Korea, the amount of daily intake of arsenic were estimated to be 77.8 μg/day. The daily intake of arsenic from the rice estimates up to 65% of ADI(acceptable daily intake) that the FAO/WHO Joint Food Additive and Contaminants Committee has set to evaluate their safeties.