Small risk of birth defects and low birth weight from living near landfill sites

The results of the study, carried out by the governmental Small Area Health Statistics Unit (SAHSU), based at Imperial College, London, has generated considerable concern as 80% of the UK’s population lives within two kilometres of the UK’s 19,196 landfill sites, which take 81% of the nation’s municipal waste. The study, published on 16 August on the Department of Health (DOH) website, looked at the rates of birth defects, low birth weight, stillbirths and cancer in the vicinity of 9,565 landfill sites. Sites not operational between 1982 and 1997 were excluded from the analysis and national registers were used to identify live births, stillbirths and congenital anomalies, including terminations.

The study found that overall, women stood a 1% increased risk of having a baby with birth defects, meaning around 100 babies a year are being affected in the UK, although the figure grows to 7% if the site contains hazardous waste. “It is unclear whether there are special effects relating to emissions which would be worse at special landfill sites,” commented the study’s lead author, Paul Elliott. “A number of them don’t handle very much hazardous waste and in the UK we have had a policy of sharing that waste with the other sites.” Other elevated rates near so-called ‘special sites’, which are more able to cope with hazardous waste, were that the risk of a heart or genital defect increased by 11%, however the increased risk of an abdominal wall defect went down to 3%.

For all landfill sites, the number of very low birth weight babies (less than 1,500 grams) was found to be around 5% higher, the number of low weight babies (less than 2,500 grams) was 4% higher, but there was no difference found in the rate of stillbirths or in the incidence of cancer.

The SAHSU study authors say that no precise explanation for these findings can be found and have recommended that further investigations into the potential toxicity of landfill emissions and possible exposure pathways is needed in order to help interpret the epidemiological findings. Factors such as crude classification of exposure or residence, and under-reporting of anomalies among live and stillborn children by district health authorities, could lead to either over or under-estimation of the risks of exposure to landfill sites, researchers say.

“This is an important study and the Government is taking it seriously,” commented Dr Pat Troop, Deputy Chief Medical Officer at the Department of Health. “The results are difficult to interpret and we need to put them into context. We cannot say that there is no risk from landfill sites, but given the small numbers of congenital anomalies and the uncertainties in the findings, we are not changing our advice to pregnant women and they should continue with the recommended ante-natal programme.”