广东省农耕土壤中四溴双酚A与六溴环十二烷的含量调查及其蓄积水平估算

Contents,distribution and composition of tetrabromobisphenol A and hexabromocyclododecane in agricultural soils of Guangdong

以广东省的农耕土壤为研究对象,利用HPLC-MS/MS法对粤北、粤东、粤西、珠三角地区6个市18个县的360份土壤样品中四溴双酚A(TBBPA)与六溴环十二烷(HBCDs)3种异构体的含量进行测定,旨在探明广东省农耕土壤中两种阻燃剂的含量、分布、异构体的构成特征,并对广东省农耕土壤中TBBPA与HBCDs的蓄积情况进行评估,以期为两者的污染防治提供依据.结果表明,(1)广东省农耕土壤中TBBPA与∑HBCDs(α、β、γ-HBCD之和)的含量范围分别为ND—7.43 ng·g^(-1)dw和ND—3.85 ng·g^(-1)dw,均值分别为0.61 ng·g^(-1)dw和0.68 ng·g^(-1)dw.(2)在采样涉及的6个市中,TBBPA平均含量高低顺序为佛山(0.91 ng·g^(-1)dw)>湛江(0.90 ng·g^(-1)dw)>汕头(0.82 ng·g^(-1)dw)>肇庆(0.44 ng·g^(-1)dw)>惠州(0.34 ng·g^(-1)dw)>韶关(0.24 ng·g^(-1)dw),∑HBCDs平均含量高低顺序为汕头(0.98 ng·g^(-1)dw)>惠州(0.97 ng·g^(-1)dw)>佛山(0.77 ng·g^(-1)dw)>湛江(0.72 ng·g^(-1)dw)>肇庆(0.35 ng·g^(-1)dw)>韶关(0.28 ng·g^(-1)dw).各采样市之间的农耕土壤中TBBPA浓度和HBCDs浓度均有显著的地区差异(方差分析,P<0.001),工业和经济更发达的珠三角地区农耕土壤中的TBBPA与HBCDs浓度明显高于粤北山区.当地阻燃剂使用相关工业年产值与∑HBCDs在农耕土壤中的污染浓度均有强相关性(P=0.021,Spearman相关系数=0.829).(3)广东省农耕土壤中α-HBCD、β-HBCD、γ-HBCD的平均丰度分别为36.1%、9.0%、54.9%,与工业产品中三者的比例有所不同,说明HBCDs在环境蓄积过程中发生了转化与重排.(4)广东省农耕土壤中的TBBPA蓄积量为4.57 t,HBCDs的蓄积量为5.10 t,说明该两种化合物在广东省农耕土壤中已经达到一定程度的蓄积.

To detect the content, distribution, storage and accumulation situation of the tetrabromobisphenol A（TBBPA） and three hexachlorocyclododecane（HBCDs） isomers in farmland soil of Guangdong province,360 soil samples were analyzed by HPLC-MS/MS. The experiment results indicated that the concentrations of TBBPA and ∑HBCDs（the sum of α-HBCD,β-HBCD and γ-HBCD） ranged from ND to 7.43 and ND to 3.85 ng·g^-1dw,with a mean value of 0.608 and0.68 ng·g^-1dw,respectively. For the 6 sampling cities,the rank of average content of TBBPA wasFoshan（0.91 ng·g^-1dw） 〉Zhanjiang（0. 90 ng·g^-1dw） 〉Shantou（0. 82 ng·g^-1dw） 〉Zhaoqing（0.44 ng·g^-1dw） 〉Huizhou（0. 34 ng·g^-1dw） 〉Shaoguan（0. 24 ng·g^-1dw）. According to the average content of ∑HBCDs,the rank was Shantou（0.98 ng·g^-1dw）〉 Huizhou（0.97 ng·g^-1dw）〉 Foshan（0.77 ng·g^-1dw）〉 Zhanjiang（0. 72 ng·g^-1dw）〉 Zhaoqing（0. 35 ng·g^-1dw） 〉Shaoguan（0.28 ng·g^-1dw）. The above results showed that the concentrations of TBBPA and HBCDs in the Pearl River delta regions were significantly higher than the mountain areas of North Guangdong province（P〈0. 001）. The spearman correlation coefficient revealed that there was positive correlation between the local annual output of flame retardants related industry and the content of ΣHBCDs in agricultural soils（P = 0.021,Spearman correlation coefficient = 0.829）. In addition,the average abundance of α,β,γ-HBCD in the agricultural soils of Guangdong province was36.1%,9.0% and 54.9%,which was different from their proportion in the industrial products. The result indicated that HBCDs were transformed and rearranged during environmental accumulation.Lastly,the accumulation of TBBPA and HBCDs in the soils was 4. 57 t and 5. 10 t respectively,which indicated that these two compounds had accumulated to a certain degree in the agricultural soils of Guangdong Province.