[Environmental surveys in the areas of Bitterfeld, Hettstedt and a comparative area in 1992-2000]

The aim of the environmental epidemiological study was to determine possible adverse effects on the health of children in the environmentally polluted areas of Bitterfeld and Hettstedt compared to the less polluted area of Zerbst (Eastern Germany). The changes of the health parameters were recorded together with the environmental changes during the time period of 6 years. The study design consisted of three repeated regional cross-sectional studies in 1992/93, 1995/96 and 1998/99. In total, 7,611 questionnaires could be analysed (participation rate: 89%, 75% and 75%). Children living in the most polluted area of Hettstedt had a noticeable higher risk for non-allergic respiratory diseases and symptoms compared to children living in the control area of Zerbst. From 1992 to 1999 a statistically significant decrease in the prevalences of these health outcomes was found. Children without indoor pollutants in their homes had the greatest benefit by the improvement of ambient air quality. The increase in lung function (FVC, FEV1) also underlines the improvement of the respiratory health. Children living in the polluted areas reported allergies more often (physician's diagnosis, allergy specific antibodies). The prevalence of asthma, the bronchial hyperreactivity and atopic eczema was increased within the observational period of 6 years. An increased prevalence was also shown for more severe allergic sensitisation (RAST classes > 17.5 kU/l), while the prevalence of hay fever increased slightly on a non-significant level. The burden with lead and cadmium was higher in children living in polluted areas and decreased during the study period except for 1997 where the lead concentration in blood increased according to the higher lead concentration in settled dust in Hettstedt at that time.