Down syndrome in births near landfill sites

Objectives The aim of the study was to examine the risk of giving birth to a child with Down syndrome associated with residence near landfill sites in England and Wales. Methods A 2-km zone around 6289 landfill sites processing special (hazardous), non-special and unknown waste type was used to indicate exposure. Postcodes within the 2-km zone were classified as ‘exposed’ and people living beyond 2 km comprised the reference population. Health outcome data were Down syndrome registrations from a national registry including 21 cytogenetic laboratories in England and Wales, for the years 1989 to 1998. With a Bayesian regression model, we calculated relative risks for the population living within 2 km of landfill sites relative to the reference population, assuming a common relative risk for all landfill sites. Adjustments were made for major confounders. Results There were 4640 cases of Down syndrome within 2 km of a landfill site. We found no excess risks of Down syndrome related to landfill sites. Adjustment for socio-economic status (SES) did not influence our estimates. There were no differences in risk between hazardous waste sites and other landfill sites. Conclusion We found no excess risk of Down syndrome in populations living near landfill sites. Copyright © 2007 John Wiley & Sons, Ltd.