SPATIAL EVALUATION OF BIRTH DEFECTS AND ENVIRONMENTAL HAZARDS IN POLAND

Abstract

ISEE-520 Introduction: The Polish Birth Defects Register (PRWWR), member of EUROCAT, registers birth defect cases comprising all types of defects and address and topographical coordinates of place of mother’s residence. A subarea (subPRWWR) in west north Poland with 653 communes (21% of communes in Poland with 6.8% Poland’s population) was selected for the study. The aim of study was to evaluate differences in spatial distribution of birth defects incidence rates within subPRWWR, identification of locations with the highest rates and description of environmental hazard profiles of these clusters. Methods: Spatial autocorrelation of the birth defect cases was tested. The birth defect cases were aggregated to communes with respect to all defects and specific groups (according to ICD10). For all communes in subPRWWR the rates of defects per 10000 births was calculated. One-side Fisher’s exact test was applied to find communes with the index significantly statistically greater than the mean for whole subPRWWR. The hazard indexes for air pollution, accumulated solid wastes, untreated sewage and percentage of population supplied chlorinated drinking water have been also aggregated to the integrated index of environmental health hazard. Results: The study covered a period of 1998-1999. In 1998, 1437 children were born with birth defects on the area of subPRWWR and 1127 children in 1999. Geostatistical autocorrelation test confirmed that clusters of birth defect cases exist in subPRWWR. The index of birth defects incidence was significantly higher in 47 communes in 1998, in 36 communes in 1999 and in 27 communes in 1998 and in 1999 combined, than the mean value for the whole subPRWWR. Discussion: Spatial analysis of the distribution of birth defects indicated that there are cluster areas where the incidence of birth defects is significantly higher than average for all cases as well as for selected groups of defects. Environmental indexes used for analysis of spatial distribution of environmental health hazards have an integrated character. In view of limited environmental data it was not possible in this pilot study to assess correlation between incidence of birth defects and indexes of environmental hazards. Further studies will require detail investigations into environmental health hazards profiles for birth defects cluster areas. The birth defects data collection will be extended to cover a period of five years and an attempt will be made to analyze potential links between the incidence of birth defects and environmental hazards.