雷州半岛典型区域土壤邻苯二甲酸酯(PAEs)污染研究

PAEs Pollution in Soils from Typical Agriculture Area of Leizhou Peninsula

在雷州半岛典型农业区共采集了71个表层土样和3个剖面土样,采用GC-FID检测方法分析了土壤中邻苯二甲酸酯(PAEs)16种化合物含量,并对其污染水平及分布特征进行了研究。结果表明,除了一个样品未检出PAEs化合物外,其余70个样品均有检出,PAEs含量(∑PAEs)在ND￣5452.7μg·kg-1之间,平均736.5μg·kg-1。属于美国国家环保总局优先控制的6种PAEs化合物中,DEP、DMP和DnBP含量超过了美国土壤PAEs控制标准,样品超标率分别为1.4%、45.07%和91.55%,其余3种优控PAEs化合物(DEHP、DnOP、BBP)的含量均低于美国标准。总的来看,雷州半岛农业土壤∑PAEs含量处于较低水平。雷州半岛农业土壤中PAEs化合物组分主要以DnBP、DEHP、DIP、BEHP和DAP为主,它们的平均含量分别为282.3、140.7、92.55、79.63和45.94μg·kg-1。在4种主要利用类型土壤中,∑PAEs含量高低排序为甘蔗地→水田→菜地→果园地;按雷州半岛各区域∑PAEs含量高低排序则为:雷州→霞山→赤坎→吴川→徐闻→廉江→麻章→坡头→遂溪。土壤剖面点各层∑PAEs残留总量总体上随着深度的增加呈下降趋势,DEHP进入土壤以后,主要吸附在土壤的表层,也基本上随深度的增加呈现递减趋势;而DnBP含量较高时,在土壤剖面中的分布呈先增加而后又随深度降低的规律。

In order to assess and analyze the pollution level and distribution character of phthalic acid esters （PAEs） in soils of Leizhou peninsula, south of China, 71 topsoil samples and 3 soil profile samples were collected from 4 functional agriculture areas of Leizhou peninsula, 16 PAEs including dimethyl phthalate（DMP）, diethyl phthalate（DEP）, diisobutyl phthalate（DIP）, di-n-butyl phthalate（DnBP）, bis（methoxyethyl） phthalate （BMP）, hexyl-2-ethylhexyl phthalate（HEP）,Bis（ethoxyethyl）phthalate （BEHP）, di-amyl phthalate（DAP）, di-n-hexyl phthalate （I）HP）, butylbenzyl phthalate（BBP）,bis（4-methyl,2-pentyl）phthalate（BMPP）, bis（2-n-butoxyethyl）phthalate（BnBP）, dicyclohexyl phthalate （DCP）, di-n-octyl phthalate（DnOP）, di-nonyl phthalate（DnP） and di-2-ethylhexyl） phthalate（DEHP） were determined by gas chromatography- FID detector （GC-FID）. Total contents of the 16 PAE compounds（∑ PAEs） in all top soils ranged from ND to 5452.7μg·kg^-1, with the average 736.51μg·kg^-1. Among 6 U.S.EPA priority pollutants of PAEs, the contents of DMP, DEP and DnBP in all top soils exceeded the control limits of PAEs in American soil by 1.4%, 45.07% and 91.55% respectively, but the contents of DEHP, DnOP and BBP were less than the control limits. The pollution level of PAEs in topsoil of Leizhou peninsula was lower than that reported in the country. The main components of PAE compounds in soils of Leizhou peninsula were DnBP, DEHP, DIP, BEHP and DAP, and their averaged concentrations in soils was 282.3, 140.7, 92.55, 79.63 and 45.94μg·kg^-1 respectively. Although distribution of ∑ PAEs in the samples was not well defined, the data suggested the order of pollution potential was sugarcane soil〉paddy field〉pot garden〉fruit garden among 4 functional agriculture areas, and that was Leizhou〉Xiashan〉Chikan〉Wuchuan〉Xuwen〉Lianjiang〉Mazhang〉Potou〉Suixi among 9 districts of Leizhou peninsula. The contents of ∑PAEs and DEHP decreased with the depth of soil profile, but when the contents of DnBP were higher, the contents of ∑ PAEs and DEHPy increased with depth earlier then decreased.