發(fā)布時(shí)間：2018-11-14 09:56

【摘要】：多環(huán)芳烴(polycyclic aromatic hydrocarbons)是一類(lèi)可以在環(huán)境中持久性存在的持久性有機(jī)污染物(POPs),通過(guò)環(huán)境遷移和食物鏈富集,對(duì)人類(lèi)健康和生態(tài)環(huán)境產(chǎn)生有害影響的化合物。近年來(lái)隨著鄱陽(yáng)湖生態(tài)經(jīng)濟(jì)區(qū)煤炭的大量使用和機(jī)動(dòng)車(chē)尾氣的大量排放,環(huán)境中的PAHs污染加劇,鄱陽(yáng)湖生態(tài)經(jīng)濟(jì)區(qū)城市圈中大氣介質(zhì)及城市農(nóng)田土壤中均檢出PAHs殘留�，F(xiàn)有的對(duì)鄱陽(yáng)湖PAHs的研究都主要是針對(duì)單一介質(zhì),對(duì)區(qū)域尺度下大氣、土壤、沉積物、水體等環(huán)境多介質(zhì)中PAHs的污染特征及環(huán)境過(guò)程的研究相對(duì)較少,缺乏全面系統(tǒng)的認(rèn)識(shí)。本次研究通過(guò)對(duì)鄱陽(yáng)湖不同介質(zhì)土壤、沉積物、水體和大氣樣品的采集,分析了不同介質(zhì)中PAHs的污染水平、組成特征和分布特征。結(jié)果表明:鄱陽(yáng)湖土壤、沉積物、水體、大氣中∑PAHs的含量平均值分別為242.64ng/g,394.74ng/g,0.25μg/L和26.07ng/m3,均低于國(guó)內(nèi)各介質(zhì)中PAHs的平均水平,土壤和沉積物表現(xiàn)為鄱陽(yáng)湖生態(tài)經(jīng)濟(jì)區(qū)PAHs的最終的匯。土壤、沉積物和大氣PM2.5中PAHs主要以4環(huán)以上的大分子PAHs存在,而水體中主要以3環(huán)以下的小分子PAHs為主,利用比值法確定了鄱陽(yáng)湖生態(tài)經(jīng)濟(jì)區(qū)PAHs污染物主要來(lái)自化石燃料燃燒,少量來(lái)自石油直接排放和生物質(zhì)的燃燒排放。鄱陽(yáng)湖生態(tài)經(jīng)濟(jì)區(qū)大氣PM2.5中PAHs在時(shí)間分布上存在差異,呈季節(jié)性變化,表現(xiàn)為冬季大于夏季;在空間分布上存在差異,PAHs整體濃度水平表現(xiàn)為南昌大于九江。季節(jié)性的變化主要是因?yàn)槎炷茉聪牧康脑黾訌亩黾恿薖AHs的輸入量,空間分布差異與南昌、九江兩地的能源消耗量不同和能源消耗結(jié)構(gòu)不同有關(guān)。分析南昌大氣PM2.5中PAHs年度變化可知,南昌市大氣PM2.5中PAHs呈逐年增加的趨勢(shì),主要是因?yàn)榻陙?lái)南昌市化石燃料的消耗能增多,同時(shí)也跟南昌市的氣候變化有關(guān),且研究發(fā)現(xiàn)PAHs的濃度與溫度、相對(duì)濕度、降雨量呈負(fù)相關(guān)。利用潛在生態(tài)風(fēng)險(xiǎn)效應(yīng)的區(qū)間低值(ERL)和效應(yīng)區(qū)間中值(ERM)的方法和加拿大魁北克省淡水沉積物中PAHs的質(zhì)量評(píng)價(jià)標(biāo)準(zhǔn),對(duì)鄱陽(yáng)湖沉積物進(jìn)行生態(tài)風(fēng)險(xiǎn)評(píng)價(jià),可知鄱陽(yáng)湖沉積物PAHs濃度小于ERL,沉積物中PAHs產(chǎn)生負(fù)面效應(yīng)幾率很小,小于生物毒性的臨界效應(yīng)濃度值,鄱陽(yáng)湖沉積物處于生態(tài)風(fēng)險(xiǎn)較低水平。同時(shí)利用加拿大魁北克省淡水沉積物中PAHs的質(zhì)量評(píng)價(jià)標(biāo)準(zhǔn)和荷蘭政府建立的一套標(biāo)準(zhǔn)對(duì)土壤中的多環(huán)芳烴進(jìn)行生態(tài)風(fēng)險(xiǎn)評(píng)價(jià)。結(jié)果顯示,土壤中的多環(huán)芳烴接近罕見(jiàn)效應(yīng)濃度值,符合低風(fēng)險(xiǎn)標(biāo)準(zhǔn)。利用Ba P的毒性當(dāng)量法(TEQ)對(duì)鄱陽(yáng)湖生態(tài)經(jīng)濟(jì)區(qū)水體和大氣進(jìn)行風(fēng)險(xiǎn)評(píng)價(jià),即把其它多環(huán)芳烴都換算為Ba P的濃度,再采用終身致癌風(fēng)險(xiǎn),進(jìn)行健康風(fēng)險(xiǎn)評(píng)價(jià)。經(jīng)計(jì)算,水體終身致癌風(fēng)險(xiǎn)為2.70×10-4,為可接受水平;大氣中成人和兒童的PAHs終身致癌超額危險(xiǎn)度R分別為1.35×10-6和5.80×10-7,小于最大可接受風(fēng)險(xiǎn)水平10-6-10-5,為可接受風(fēng)險(xiǎn)水平。
[Abstract]:Polycyclic aromatic hydrocarbons (PAHs) (polycyclic aromatic hydrocarbons) are a class of persistent organic pollutants (POPs),) which can be persistent in the environment and have harmful effects on human health and ecological environment through environmental transport and food chain enrichment. In recent years, with the large use of coal and the emission of vehicle tail gas, the PAHs pollution in the environment has been intensified, and PAHs residues have been detected in both the atmospheric media and the farmland soil of the ecological economic zone of Poyang Lake. The existing studies on PAHs in Poyang Lake are mainly focused on the single medium, and the study on the pollution characteristics and environmental process of PAHs in the atmosphere, soil, sediment, water and other environmental multi-media at regional scale is relatively few, lacking of comprehensive and systematic understanding. Based on the collection of soil, sediment, water and atmosphere samples from different media in Poyang Lake, the pollution level, composition and distribution of PAHs in different media were analyzed. The results show that the mean values of 鈭，

本文編號(hào)：2330838