Division of Occupational and Environmental Medicine and Psychiatric Epidemiology, Department of Laboratory Medicine, Lund University Hospital, SE-221 85 Lund, Sweden. lars.hagmar@med.lu.se
BACKGROUND: An important question is whether human serum levels of persistent organic pollutants has continued to decrease during the last decades. The aim of this study was to assess intra-individual variations over time of serum levels of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethene (p,p'-DDE) and hexachlorobenzene (HCB), considering the impact of a number of possible determinants. METHODS: Blood samples were drawn for the same 39 subjects in 1991 and 2001. Interviews were made at both occasions. Lipid adjusted serum concentrations of CB-153, p,p'-DDE and HCB were determined in both sets of blood samples using gas chromatography-mass spectrometry. The fatty acid composition of the serum lipids was analyzed by means of gas-liquid chromatography. RESULT: The CB-153 concentrations in serum had averagely decreased with 34% in between 1991 and 2001 (p