title: Levels and profiles of organohalogenated contaminants in human blood from Egypt.
abstract: Concentrations of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and some organochlorine pesticides (OCPs) were determined in serum of Egyptian colorectal cancer patients (n = 35) and compared to a healthy control group (n = 32). p,p'-DDE (the major metabolite of DDT) was the most frequently detected contaminant with the highest concentration (median = 131 ng/g lw) in all studied serum samples. BDE-209 was the least frequently detected contaminant with a median concentration <0.3 ng/g lw. The contamination profile in patients and controls was almost identical with p,p'-DDE showing the highest median contribution (77%) and oxychlordane the lowest (1%). The low p,p'-DDT/p,p'-DDE ratio (3.7%) in serum implies bioaccumulation and past exposure to DDT (c.f. recent and ongoing intake). Statistical analysis revealed no significant differences (P > 0.05) between the levels of target contaminants in serum of patients and the control group. Gender, age and body mass index (BMI) were investigated as potential factors influencing serum contaminant levels. ΣDDT, hexachlorobenzene and pentachlorophenol concentrations showed significant positive associations with age and/or BMI of the participants. Comparison with other countries revealed concentrations of PBDEs and PCBs in Egyptian serum among the lowest reported worldwide.
authors.affiliation: Division of Environmental Health and Risk Management, School of Geography, Earth, and Environmental Sciences, University of Birmingham, Birmingham, B15 2TT, United Kingdom; Department of Analytical Chemistry, Faculty of Pharmacy, Assiut University, 71526, Assiut, Egypt. Electronic address: mae_abdallah@yahoo.co.uk.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abou-Elwafa Abdallah
authors.affiliation: Medical Oncology Department, South Egypt Cancer Institute, Assiut University, Assiut, Egypt.
authors.forename: Amen Hamdy
authors.initials: AH
authors.lastname: Zaky
authors.affiliation: Toxicological Center, University of Antwerp, Universiteitsplein 1, 2610, Wilrijk, Belgium.
authors.forename: Adrian
authors.initials: A
authors.lastname: Covaci
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002706:Chlordan / Q000031:analogs & derivatives / Q000097:blood; D015179:Colorectal Neoplasms / Q000097:blood*; D003633:Dichlorodiphenyl Dichloroethylene / Q000097:blood; D004534:Egypt; D005260:Female; D055768:Halogenated Diphenyl Ethers / Q000097:blood*; D006581:Hexachlorobenzene / Q000097:blood; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000097:blood; D008297:Male; D010575:Pesticides / Q000097:blood*; D011078:Polychlorinated Biphenyls / Q000097:blood*
chemical_list: D055768:Halogenated Diphenyl Ethers; D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D002706:Chlordan; C008743:oxychlordane; D003633:Dichlorodiphenyl Dichloroethylene; D006581:Hexachlorobenzene; D011078:Polychlorinated Biphenyls; C010902:decabromobiphenyl ether
keywords: Colorectal cancer; Egyptian blood; OCPs; Organohalogen contaminants; PBDEs; PCBs