浙江省嘉善县人群结直肠癌发病与有机氯污染的关系

Relationship between organochlorine pollution in soil and rice and the incidence of colorectal cancer in Jiashan county,Zhejiang province

目的 探讨有机氯污染与结直肠癌发病的关系。方法 采用分阶段整群随机抽样的方法,按结直肠癌标化发病率高低在嘉善县抽取11个乡镇,再随机抽取行政村、自然村,采集各自然村的大米和稻田土壤样品,测定其中各有机氯指标的含量,结合各乡镇的结直肠癌发病资料,用Spearman等级相关进行统计分析。结果 大米和土壤中农药六六六(六氯环己烷,HCH)、滴滴涕(二氯二苯三氯乙烷,DDT)含量均未超过国家标准。各乡镇的结直肠癌标化发病率、各乡镇大米中的δ-HCH、γ-HCH、五氯酚钠以及土壤中δ-HCH含量差异存在显著性;结直肠癌标化发病率与大米中总DDT含量、直肠癌标化发病率与大米中总DDT、1,1-双(对-氯苯基)二氯乙烯(PP’-DDE)含量、结肠癌标化发病率与大米中多氯联苯(PCB_s)的1245组分含量之间存在统计学上的显著相关关系,相关系数分别为0.636、0.691、0.716、0.658,P值均<0.05。结论 直肠癌与有机氯农药(主要是大米中总DDT、PP’-DDE)含量存在统计学上显著的相关关系,而结肠癌与大米中PCB_s的1245组分含量存在显著相关关系。但作为生态学研究,其结论还有待于进一步的确证。

Objective To study the relationship between orgnochlorine and colorectal cancer. Methods With multistage cluster random sampling, 11 towns were drawn based on the standarized incidence of colorectal cancer. Administrative and natural villages were drawn subseqently. Rice and soil samples in the paddy fields were colected in the villages. The contents of organochlorine were detected. Rank correlation analysis was performed together with the data of colorectal cancer incidence. Results The contents of hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) in both rice and soil samples were below the amounts of the country. Statistics showed that the standardized incidence rates were significantly different among the 11 towns. The contents of δ-HCH, γ-YHCH,sodium pentachlorophenate in rice and those of δ-HCH in soil were statistically different among the towns through the rank sum test. The standardized incidence of colorectal cancer was significantly connected with the content of total DDT in rice while rectal cancer with total DDT and PP'-DDE and colon caner with 1245 of polychlorinated biphenyl (PCBs). The correlation coeffcients wer 0. 636, 0.691, 0. 716 and 0.658 respectively (P<0.05). Conclusions Rectal cancer was statistically correlated with organochlorine, mainly for total DDT and diclorodiphenyldichloroeethylene (PP'-DDE). Colon cancer was significantly associated with 1245 of PCBs. Further study should be performed since this research was only an ecological study.