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 anomalies associated with residence near hazardous-waste landfill sites in Europe. Methods We used data from seven regional registers of congenital anomalies in five countries. We studied 1089 livebirths, stillbirths, and terminations of pregnancy with non-chromosomal congenital anomalies and 2366 control births without malformation, whose mothers resided 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 cases/511 controls living 0–3 km from sites, 794/1855 living 3–7 km from sites; combined odds ratio 1·33 [95% Cl 1·11–1·59], adjusted for maternal age and socioeconomic status). There was a fairly consistent decrease in risk with distance away from the sites. A significantly raised odds ratio for residence within 3 km of a landfill 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 anomalies 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 between landfill sites but power to detect such differences was low. Interpretation This study shows a raised risk of congenital anomaly in babies whose mothers live close to landfill sites that handle hazardous chemical wastes, although there is a need for further investigation of whether the association of raised risk of congenital anomaly and residence near landfill sites is a causal one. Apparent differences between malformation subgroups should be interpreted cautiously.