Risk of adverse birth outcomes near landfill sites

Risk of adverse birth outcomes near landfill sitesEvidence suggests that it is probably safe for fetuses to develop near landfill sites Editor-Elliott et al report a large geographical study of adverse birth outcomes in populations living near landfill sites. 1 They conclude that there are small excess risks of congenital anomalies and low birth weight in such populations.Although they advise caution when interpreting their results, the study is nevertheless hailed by the press and by environmental groups as evidence that living near such sites is hazardous to health. 2 The concerns felt by parents, often with no opportunity to move elsewhere, are fuelled, and perhaps on no grounds.Scientists contribute to the media generated intrigue in subtle ways.For example, the description of the paper in an editorial by McNamee and Dolk as a report "on the risks to fetuses associated with residence" when "a study of the statistical association between reported anomalies and residence" would have been more accurate and less sensationalist. 3 Health authorities are left to pick up the pieces when a story breaks, with no advance warning, about a landfill site in their area.Another interpretation of the results of Elliott et al is that this essentially negative study goes some way to reassuring other scientists who have been studying this question that it is probably safe for fetuses to develop near such sites.Any scientist who has any experience of multivariate epidemiological analysis would have to admit that such small and inconsistent excesses and deficits, even though significant, could well be attributable to inadequately adjusted social deprivation, to name but one of many important confounders.The fact that there was no increase after the landfill sites became operational, and a significant deficit of anomalies around landfill sites in Scotland, must leave even the most determined author feeling uneasy about suggesting a causal association.Epidemiological techniques used in this study are blunt instruments unlikely to detect subtle or unidentified effects.Perhaps it is time for epidemiologists to admit that their tools are inadequate to answer this question.Other scientists should take this forward by developing better techniques to identify any putative agents in the gas emissions, leachates, and soil that may be of sufficiently high concentrations to affect human health.Many of these landfill sites are unattractive and foul smelling, attracting seagulls and peppering the landscape with rubbish.More imaginative long term wastemanagement solutions are long overdue.