东莞地下水邻苯二甲酸酯分布特征及来源探讨

The distribution characteristics and source of phthalic acid esters in groundwater of Dongguan

在广东东莞地区采集了59组地下水水样和9组地表水水样,采用气相色谱-质谱联用技术进行测定。结果表明,地下水中邻苯二甲酸酯(PAEs)的检出率为39.0%,6种PAEs的质量浓度在未检出～6.70μg/L。其中,邻苯二甲酸双(2-乙基己基)酯(DEHP)检出率最高,为22.0%,最大值为6.20μg/L;邻苯二甲酸二正丁酯(DnBP)次之,检出率为20.3%,最大值为4.70μg/L;邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)以及邻苯二甲酸丁苄酯(BBP)均仅有个别检出;邻苯二甲酸二正辛酯(DnOP)未检出;DnBP在部分地下水中有少量超标。地下水中PAEs主要分布于东莞市的周边地区,部分出现于厚街镇的东部和北部;在东莞地区的地下水水样中,以单种PAEs检出为主;地下水中PAEs与地表水中PAEs的分布特征存在明显的相似性,均以DnBP和DEHP为主。含PAEs地表废水的下渗以及环境中废弃塑料制品PAEs的释放是东莞地区地下水中PAEs的重要来源。

59 groundwater samples and 9 surface water samples were collected from Dongguan area in Guangdong.Gas chromatography and mass spectrum（GC/MS） was applied to detect the contented of phthalic acid esters（PAEs） in these water samples.The result showed that the detection rate of PAEs,include dimethyl phthalate（DMP）,diethyl phthalate（DEP）,di-n-butyl phthalate（DnBP）,butyl benzyl phthalate（BBP）,bis（2-ethylhexyl） phthalate（DEHP）,and di-n-octyl phthalate（DnOP）,in groundwater was 39.0%,the total concentration of six kinds of PAEs was at 0-6.70 μg/L.Among them,DEHP had the highest detection rate（22.0%） and detection value（6.20 μg/L）,which was followed by DnBP,with the detection rate of 20.3% and detection value of 4.70 μg/L respectively;DMP,DEP,and BBP were detected in only a few of samples;there was no DnOP detected in all these groundwater samples;while the concentration of DnBP in few groundwater samples was exceeded drinking water standard.The PAEs polluted groundwater was mainly distributed in the surrounding of Dongguan area,only some of them were distributed in the east and north of Houjie town,and most of groundwater samples were detected containing only one kind of PAEs.There was an obvious comparability between the PAEs distribution in groundwater and in surface water.DEHP and DnBP were also the dominating PAEs in surface water.PAEs which released from the abandoned plastic products and infiltrated from the surface waste water were the important sources of PAEs in groundwater of Dongguan.