Human exposure to persistent organic pollutants in West Africa--a temporal trend study from Guinea-Bissau.
BACKGROUND
Humans, independent on where they live, are exposed to complex and various mixtures of chemicals, including persistent organic pollutants (POPs). The variability of the exposure depends on sources of the chemicals and is influenced by e.g. geography, social and cultural heritage. While exposures to POPs are frequently studied in populations from developed industrial countries, very little is known on levels and trends of POPs in developing countries, especially in Africa.


OBJECTIVE
The aim of the present study was to investigate levels and temporal trends of POPs in adults from Guinea-Bissau.


METHODS
Serum samples were obtained from an open cohort of police officers in Guinea-Bissau. Repeated samples from 33 individuals were obtained at five time points between 1990 and 2007, in all 147 samples. Pooled serum samples were extracted and cleaned-up prior to analysis by gas chromatography and mass spectrometry. The concentration of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (4,4'-DDT) and its metabolites, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and hexachlorocyclohexanes (HCHs) were determined.


RESULTS
The major POP found in all samples was 1,1-dichloro-2,2-bis(4-chlorophenyl)ethene (4,4'-DDE) followed by 4,4'-DDT. 4,4'-DDE, 4,4'-DDT, PCBs and beta- and gamma-HCH were significantly decreasing over time. The PBDEs were found at low concentrations, with an increasing temporal trend for BDE-153.


CONCLUSIONS
National and international management may be behind the observed decreased organohalogen compound concentrations in humans from Guinea-Bissau from the early 1990's and onwards, similarly to the development of these compounds in humans from industrial countries. In contrast, PBDEs follow a trend of increasing concentrations even though at low levels.
Environmental Chemistry Unit, Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden. linda.linderholm@mmk.su.se
Linda
L
Linderholm
Antonio
A
Biague
Fredrik
F
Månsson
Hans
H
Norrgren
Ake
A
Bergman
Kristina
K
Jakobsson
D000328:Adult; D003634:DDT / Q000097:blood; D003633:Dichlorodiphenyl Dichloroethylene / Q000097:blood; D003632:Dichlorodiphenyldichloroethane / Q000097:blood; D004781:Environmental Exposure / Q000032:analysis* / Q000706:statistics & numerical data; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000097:blood*; D005260:Female; D006169:Guinea-Bissau; D055768:Halogenated Diphenyl Ethers / Q000097:blood; D001556:Hexachlorocyclohexane / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D009930:Organic Chemicals / Q000097:blood*; D011078:Polychlorinated Biphenyls / Q000097:blood; D013995:Time; D055815:Young Adult
D004785:Environmental Pollutants; D055768:Halogenated Diphenyl Ethers; D009930:Organic Chemicals; D003633:Dichlorodiphenyl Dichloroethylene; D001556:Hexachlorocyclohexane; D003634:DDT; D011078:Polychlorinated Biphenyls; D003632:Dichlorodiphenyldichloroethane