Polychlorinated Dibenzo-p-dioxin and Polychlorinated Dibenzofuran Contamination in Soil and Home-Produced Chicken Eggs Near Pentachlorophenol Sources
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- 作者：Martha E. Harnly ; Myrto X. Petreas ; Jennifer Flattery ; and Lynn R. Goldman
- 刊名：Environmental Science & Technology
- 出版年：2000
- 出版时间：April 1, 2000
- 年：2000
- 卷：34
- 期：7
- 页码：1143 - 1149
- 全文大小：106K
- 年卷期：v.34,no.7(April 1, 2000)
- ISSN：1520-5851
文摘
The sources and pathways of food chain contaminationof the persistent and toxic polychlorinated dibenzo-p-dioxins(PCDDs) and polychlorinated dibenzofurans (PCDFs) areunclear. PCDD/PCDF levels in eggs from chickens raised inbackyards near Oroville, CA, near a former pentachlorophenol(PCP) wood treatment facility (WTF) and four formerPCP waste burners, were previously reported to be elevated(above a level of significant cancer risk, i.e., 1 part pertrillion (ppt) international toxicity equivalent (ITEQ) and abovelevels in eggs from a similar rural area with no suchfacilities). Limited sampling suggested associations withlow ppt soil levels. Further investigations are reported here.Soil concentrations in samples (n = 26) collected fromthe foraging area of a single Oroville backyard have ageometric mean of 30 ppt ITEQ and are uniform, suggestingairborne deposition. Additional samples were collectedfrom homes in Oroville and Stockton, CA also near a formerPCP WTF. Geometric mean dioxin levels in eggs are 2.2and 1.8 ppt ITEQ for Oroville (n = 35), and Stockton (n =5), with 78% of samples above 1 ppt. Correspondingsoil geometric means are 6.2 (n = 17) and 6.6 (n = 5) pptITEQ. Regression models estimate that soil concentrationsof 0.38 and 2.7 ppt ITEQ, depending on whether chickens free-forage, predict an egg concentration of 1 ppt ITEQ. Thecombined evidence suggests that local industrial sourcescan contribute to environmental contamination. The soilconcentrations associated with significant egg contaminationare low, much lower than the dioxin level of 1000 ppt,frequently used for children's ingestion exposures, andpotentially widespread. A broad and global concern for PCDD/PCDF sources and environmental levels, particularly withrespect to human consumption of animal products, isunderscored.