Intra-individual variations and temporal trends in dioxin levels in human blood 1987-2002

Objectives: In Sweden, an important source for exposure to persistent organochlorine pollutants, such as PCDD and PCDF, is through intake of fatty fish from the Baltic Sea off the Eastern coast of Sweden. The present study assesses temporal trends for human levels of PCDD/F between 1987 and 2002 among 26 men from Sweden. In addition, we investigate the impact of potential determinants (age, relative change in BMI and fish consumption) on the relatively change in individual PCDD/F congener levels between 1987 and 2002. Methods: In 1987, nine of the men did not eat fatty fish from the Baltic Sea, eight had a moderate intake, and nine were high consumers. For the same individuals,blood samples were collected in 1987 as well as in 2002, and the concentrations of seven PCDD and 10 PCDF congeners were analyzed at the same laboratory. Results: The WHO-TEQ levels for PCDD/F did not significantly change over the 15-year period. There were, however, some specific congeners that significantly had changed over time. None of the investigated determinants were associated with the change over time for the specific PCDD/F congeners. Conclusion: The present study may be of importance for risk assessment and setting standards for food contamination with PCDD/F, especially regarding intake of fatty fish from the Baltic Sea.