RISK OF CONGENITAL-ANOMALIES NEAR HAZARDOUS-WASTE LANDFILL SITES IN EUROPE - THE EUROHAZCON STUDY

Background Waste-disposal sites are a potential hazard to health. This study is a multicentre case-control study of the risk of congenital a nomalies associated with residence near hazardous-waste landfill sites in Europe. Methods We used data from seven regional registers of cong enital anomalies in five countries. We studied 1089 livebirths, stillb irths, and terminations of pregnancy with non-chromosomal congenital a nomalies and 2366 control births without malformation, whose mothers r esided within 7 km of a landfill site; 21 sites were included. A zone within 3 km radius of each site was defined as the ''proximate zone'' of most likely exposure to teratogens. Findings Residence within 3 km of a landfill site was associated with a significantly raised risk of congenital anomaly (295 eases/511 controls living 0-3 km from sites, 7 94/1855 living 3-7 hm from sites; combined odds ratio 1.33 [95% CI 1.1 1-1.59], adjusted for maternal age and socioeconomic status). There wa s a fairly consistent decrease in risk with distance away from the sit es. A significantly raised odds ratio for residence within 3 km of a l andfill site was found for neural-tube defects (odds ratio 1.86 [1.24- 2.79]), malformations of the cardiac septa (1.49 [1.09-2.04]), and ano malies of great arteries and veins (1.81 [1.02-3.20]). Odds ratios of borderline significance were found for tracheo-oesophageal anomalies ( 2.25 [0.96-5.26]), hypospadias (1.96 [0.98-3.92]), and gastroschisis ( 3.19 [0.95-10.77]). There was little evidence of differences in risk b etween landfill sites but power to detect such differences was low. In terpretation This study shows a raised risk of congenital anomaly in b abies whose mothers live close to landfill sites that handle hazardous chemical wastes, although there is a need for further investigation o f whether the association of raised risk of congenital anomaly and res idence near landfill sites is a causal one. Apparent differences betwe en malformation subgroups should be interpreted cautiously.