Hormone levels and sexual development in Flemish adolescents residing in areas differing in pollution pressure.

In 2002, the Centre for Environment and Health in Flanders, Belgium started a human biomonitoring program. For 1679 adolescents, residing in nine study areas with differing pollution pressure, hormone levels and the degree of sexual maturation were measured. Possible confounding effects of lifestyle and personal characteristics were taken into account. Participants from the nine different study areas had significantly different levels of sex hormones (total and free testosterone, oestradiol, aromatase, luteinizing hormone) and the thyroid hormone free triiodothyronine, after correction for confounders. Significantly higher hormone concentrations were measured in samples from participants residing in the area around the waste incinerators, while significantly lower values were found in participants residing in the Albert Canal zone with chemical industry. Sexual maturation of boys as well as girls tended to be somewhat slower in the industrial city of Antwerp and in the Antwerp harbour compared to the other areas in Flanders. Even within the same study area, significant differences in hormone levels could be observed between sub-areas. Data on the internal exposure of the same adolescents to lead, cadmium, PCBs, p,p'-DDE, HCB, 1-hydroxypyrene and t,t'-muconic acid have already been published. The observed differences in hormone levels and in sexual maturation could however only in part be explained by the measured differences in internal exposure to pollutants, suggesting that also other pollutants and other factors that vary in function of the area of residence could play a role. Nevertheless, our results also suggest that local (environmental) factors, acting within a short distance, might influence the measured hormone levels and degree of sexual maturation.

Internal exposure to pollutants measured in blood and urine of Flemish adolescents in function of area of residence.

The Centre for Environment and Health in Flanders, the Northern part of Belgium, started a biomonitoring program on adolescents in 2003. 1679 adolescents residing in nine areas with different patterns of pollution participated in the study. Possible confounding effects of lifestyle and personal characteristics were taken into account. The geometric mean levels of cadmium and lead in whole blood amounted to 0.36 and 21.7 microg l(-1), those of PCBs, DDE and HCB in serum to 68, 94 and 20.9 ng g(-1) fat, and those of 1-hydroxypyrene and t,t'-muconic acid in urine to 88 ng g(-1) creatinine and 72 microg g(-1) creatinine. Significant regional differences in internal lead, cadmium, PCBs, DDE and HCB exposure were observed in function of area of residence, even after adjustment for age, sex, smoking (and body mass index for the chlorinated compounds). Compared to a reference mean, internal exposure was significantly higher in one or more of the areas: Cd and Pb in the Antwerp agglomeration, Cd in the Antwerp harbour, PCBs in the Ghent agglomeration, PCBs, DDE and HCB in the Ghent harbour, Cd, PCBs, DDE and HCB in the rural area, DDE in Olen and in the Albert canal areas. Adolescents living in an area with intensive fruit cultivation (showing overall the lowest values) and, surprisingly, in areas around household waste incinerators (average of six areas), had no significantly increased internal exposures. Subjects from separate areas around waste incinerators showed significant differences in body load of various environmental contaminants.