A resource and pathway for potential risk of the contamination of Taichung Wuri of heavy metals for croplands

本研究主要目的為探討利用線性迴歸分析方法計算烏日區稻米鉛污染情形之可行性。本研究使用現地採樣所得之觀測資料進行線性迴歸分析，並將採樣結果帶入迴歸公式回推稻米污染情形，進而推測本地區稻米污染途徑與來源。 現地採樣結果除大氣與渠道底泥鉛濃度外，土壤、稻米、植物體與稻葉鉛濃度在威宇金屬附近濃度偏高。稻葉和土壤鉛濃度對稻米鉛濃度做線性迴歸結果中稻葉與稻米之R2為0.55，P-value小於0.001，土壤與稻米之R2為0.097，P-value為0.024，相較之下稻葉與稻米之相關性較為顯著；大氣鉛濃度對稻米與稻葉鉛濃度線性迴歸之P-value皆小於0.05，可判斷有一定程度之相關性。但大氣和土壤鉛濃度的P-value則為0.24，顯著性較低。推測本地區鉛米的主要污染途徑應為受污染土壤揚塵由葉面進入植物體，傳輸至稻穗中。 在102年第一期大氣鉛濃度偏低，此原因可能為威宇後門採樣點(管制地號336)採集失敗使得大氣鉛濃度數值不符現況所致。在102年第二期的土壤、大氣、稻米和稻葉之觀測值皆較前三期高。The purpose of this project is to investigate the contamination of heavy metal, lead and the organic pollutant, dioxin in the paddy fields contaminated by lead. Following the practice management of the paddy, two growing seasons in a year, in Taiwan, field campaigns including the sampling of soil, plant, air and water, sediment were conducted. Using linear regression to analyze the correlation of these data, we can know the pathway of lead pollution in this area. The lead concentration of soil, rice, plant, and rice leaf are obviously high around Wei-Yu Metal Company. The linear regression results show that R2 is 0.55 and P-value less than 0.001 between lead of rice and rice leaf, R2 is 0.097 and P-value is 0.024 between lead of rice and soil. By comparison rice and rice leaf are statistically significant difference. The P-value less than 0.05 between air and rice, and between air and rice leaf, but P-value is 0.24 between air and soil. It can be inferred that the contaminated rice is mainly caused from the dust emission. The data of air in season one in 2013 are low, possibly because sampling failure at Wei-Yu Metal Company back door. The data of soil, air, rice, rice leaf in season two in 2013 are higher than three other season.第一章 研究緣起與目的 1 1.1、研究緣起 1 1.2、研究目的 1 第二章 文獻回顧 2 2.1 鉛米污染案例 2 2.2 鉛米事件調查報告 3 2.3 重金屬鉛傳遞路徑 4 第三章 研究方法 5 3.1、研究流程 5 3.2、現地採樣 6 3.3、重金屬分析 10 第四章 結果與討論 11 4.1、現地採樣結果 11 4.1.1、樣本分析結果 11 4.1.2、線性迴歸結果 16 4.2、迴歸分析回推稻米鉛濃度 18 4.2.1、GTx模擬結果 18 4.2.2、迴歸結果之稻米平均鉛濃度計算 20 4.3、八大重金屬與戴奧辛指紋分析 24 4.3.1、八大重金屬指紋分析 24 4.3.2、戴奧辛指紋分析 30 第五章 結論與建議 33 5.1、結論 33 5.2、建議 34 參考文獻 36 附錄 烏日區五期鉛濃度採樣資料 3