隨著經濟(ji)的快速(su)發展(zhan)和科(ke)學技術的不(bu)斷(duan)進步，人類在(zai)生產活動過程中排放的污(wu)(wu)染(ran)物已經對(dui)自然(ran)環(huan)境(jing)造成了(le)嚴(yan)重(zhong)(zhong)(zhong)(zhong)影響，其(qi)(qi)中重(zhong)(zhong)(zhong)(zhong)金(jin)(jin)(jin)屬(shu)(shu)(shu)污(wu)(wu)染(ran)尤(you)為(wei)突出(chu)。化(hua)學上(shang)跟據金(jin)(jin)(jin)屬(shu)(shu)(shu)的密度(du)(du)把金(jin)(jin)(jin)屬(shu)(shu)(shu)分為(wei)重(zhong)(zhong)(zhong)(zhong)金(jin)(jin)(jin)屬(shu)(shu)(shu)和輕(qing)金(jin)(jin)(jin)屬(shu)(shu)(shu)，其(qi)(qi)中密度(du)(du)大于4.5g/cm3的金(jin)(jin)(jin)屬(shu)(shu)(shu)為(wei)重(zhong)(zhong)(zhong)(zhong)金(jin)(jin)(jin)屬(shu)(shu)(shu)。如(ru): Au、Ag、Cu、Pb、Zn、Ni、Co、Cr、 Hg、Cd等大約45種。As在(zai)定(ding)義上(shang)講(jiang)雖不(bu)屬(shu)(shu)(shu)于重(zhong)(zhong)(zhong)(zhong)金(jin)(jin)(jin)屬(shu)(shu)(shu)范(fan)疇(chou)，但因為(wei)其(qi)(qi)行(xing)為(wei)與(yu)來(lai)源以(yi)及(ji)危害都與(yu)重(zhong)(zhong)(zhong)(zhong)金(jin)(jin)(jin)屬(shu)(shu)(shu)相累(lei)似，故(gu)通常將As也列入重(zhong)(zhong)(zhong)(zhong)金(jin)(jin)(jin)屬(shu)(shu)(shu)的討論范(fan)疇(chou)。從環(huan)境(jing)污(wu)(wu)染(ran)的角度(du)(du)說，重(zhong)(zhong)(zhong)(zhong)金(jin)(jin)(jin)屬(shu)(shu)(shu)是指包括Hg、Cd、Pb、Gr 以(yi)及(ji)準金(jin)(jin)(jin)屬(shu)(shu)(shu)As等生物毒(du)性顯(xian)著的金(jin)(jin)(jin)屬(shu)(shu)(shu)。重(zhong)(zhong)(zhong)(zhong)金(jin)(jin)(jin)屬(shu)(shu)(shu)具(ju)有難(nan)降解、易積累(lei)、毒(du)性大和隱蔽性、長期性、不(bu)可逆性等特點,不(bu)僅污(wu)(wu)染(ran)了(le)城(cheng)市(shi)(shi)土(tu)壤(rang)(rang),使其(qi)(qi)土(tu)壤(rang)(rang)生態環(huan)境(jing)嚴(yan)重(zhong)(zhong)(zhong)(zhong)惡化(hua)，還通過地表徑(jing)流、地下水、食物鏈等途徑(jing)進入人體，嚴(yan)重(zhong)(zhong)(zhong)(zhong)危害城(cheng)市(shi)(shi)居民的身體健康，因此土(tu)壤(rang)(rang)重(zhong)(zhong)(zhong)(zhong)金(jin)(jin)(jin)屬(shu)(shu)(shu)研究日益(yi)受到人們的重(zhong)(zhong)(zhong)(zhong)視。

　　食品、土(tu)(tu)(tu)壤、水(shui)質(zhi)逐漸被(bei)工業廢(fei)氣、廢(fei)水(shui)、廢(fei)渣所污染，甚至有些人直(zhi)接用(yong)工業廢(fei)水(shui)澆灌莊稼，造成土(tu)(tu)(tu)壤耕作層內的鎘(ge)、銅、砷、鉻、汞、鎳、鐵、鋁、鋅、錳(meng)、銅等(deng) 重(zhong)(zhong)(zhong)(zhong)金(jin)屬(shu)(shu)(shu)大(da)量富積、積累(lei)，特別是城市郊區現象(xiang)(xiang)更為嚴重(zhong)(zhong)(zhong)(zhong)；加上大(da)量使用(yong)無機化學農藥等(deng)致使蔬(shu)菜(cai)和(he)魚類體內的重(zhong)(zhong)(zhong)(zhong)金(jin)屬(shu)(shu)(shu)含量嚴重(zhong)(zhong)(zhong)(zhong)超標的情況，不斷在(zai)人體內積累(lei)，導致 消費者重(zhong)(zhong)(zhong)(zhong)金(jin)屬(shu)(shu)(shu)慢(man)性(xing)中毒現象(xiang)(xiang)發(fa)(fa)(fa)生，國內已發(fa)(fa)(fa)生多起重(zhong)(zhong)(zhong)(zhong)金(jin)屬(shu)(shu)(shu)集體中毒事(shi)件，已引起政府(fu)的高度重(zhong)(zhong)(zhong)(zhong)視和(he)社會各界的廣泛關注(zhu)，但是當前重(zhong)(zhong)(zhong)(zhong)金(jin)屬(shu)(shu)(shu)測(ce)定(ding)方法(fa)測(ce)定(ding)速(su)度慢(man)、步(bu)驟 繁瑣且儀器昂貴。基于這種(zhong)形勢，我們開發(fa)(fa)(fa)出了重(zhong)(zhong)(zhong)(zhong)金(jin)屬(shu)(shu)(shu)快速(su)測(ce)定(ding)方法(fa)，可對(dui)蔬(shu)菜(cai)、食品、土(tu)(tu)(tu)壤、有機肥、煙葉(xie)等(deng)樣品中的鉛、砷、鉻、鎘(ge)、汞等(deng)進行快速(su)聯(lian)合測(ce)定(ding)。

　　土壤重金屬檢(jian)測(ce)儀檢(jian)測(ce)原理：樣品經消(xiao)化后(hou)，所有形態的(de)(de)重金屬(包括砷(shen)、鉛、鎘、鉻、汞、鎳、鐵(tie)、鋁(lv)、鋅、錳、銅等(deng))都轉化為離子型態，加入相關(guan)(guan)檢(jian)測(ce)試劑后(hou)顯色，在(zai)一(yi)定(ding)濃度范(fan)圍內溶液顏(yan)色的(de)(de)深淺與重金屬的(de)(de)含量呈比例關(guan)(guan)系，服(fu)從朗伯--比爾(er)定(ding)律，再(zai)通(tong)過儀器進(jin)行測(ce)定(ding)得出(chu)含量值，與國家標(biao)(biao)準農產品安全質量無(wu)公(gong)害蔬菜安全要求允許限量的(de)(de)標(biao)(biao)準進(jin)行比較，來判斷蔬菜樣品重金屬含量。

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