Landfill sites linked to risk of birth defects

Babies born near landfill sites for hazardous waste are at extra risk of being underweight at birth or suffering congenital defects such as spina bifida, a study has revealed.

Birth defects are most likely in babies born near the 774 special landfill sites in Britain which take hazardous industrial waste, says a report commissioned by the Department of Health.

But the increased risks of abnormalities are generally less than 10 per cent and it was not possible to determine landfill sites were the cause, it said.

More research was needed to establish whether toxic emissions from buried waste were behind the higher rate of birth defects or whether factors such as greater social deprivation in areas near waste sites and general ill-health were involved.

Some 80 per cent of the population lives within two kilometres of one of the 19,196 landfill sites in the UK. Many sites are no longer operational.

The main dumps, usually in old quarries, take more than 80 per cent of the municipal waste. The special sites take toxic waste such as solvents, heavy metals and chemicals. There has been little research to establish whether toxic chemicals can escape from the sites and damage human health.

The latest study, the most extensive of its kind undertaken, aimed to establish whether the rate of congenital abnormalities and low birth-weight babies was higher near landfill sites.

Researchers from Imperial College, London, looked at the birth defects in more than 8.2 million babies born near 9,565 landfill sites that were operational between 1982 and 1997.

They found the rate of low birth-weight babies was 5 per cent higher than expected. It was also 4 per cent higher than expected for very underweight babies. The rate of minor congenital abnormalities was 1 per cent higher than expected among children living within two kilometres of an ordinary landfill site, and 7 per cent more than expected near a hazardous waste site.

Rates of spina bifida were 5 per cent higher than expected near domestic landfill sites and 7 per cent higher near hazardous sites.

Rates of abdominal wall defects, gut problems, and genital defects in boys were also generally higher, but they were not always supported by data on hospital admissions.

Findings for heart defects were inconclusive. There was no excess risk of stillbirths and no link to increases in cancer, particularly childhood leukaemia.

Out of 660,000 births each year, 10,000 to 12,000 babies will have congenital defects. The results suggest that 100 babies with congenital defects, 2,500 with a low birth-weight and 280 with very low birth-weight could be related to living near a landfill site.

Professor Paul Elliott, who led the study, said: "We know of no causal mechanism that might explain our findings, and there is considerable uncertainty as to the extent of any possible exposure to chemicals found in landfills. We need to know an awful lot more about what goes in and what comes out of landfill sites and what gets into people."

Dr Pat Troop, the Government's deputy chief medical officer, said the findings were complex and further research was either under way or being commissioned.

"We cannot say there is no risk associated with landfill sites but, given the small number 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 antenatal programme," she said.

Professor Charles Rodeck, a specialist in foetal medicine at University College, London, said scientists still had "almost no idea" about what caused congenital defects, but women should be reassured by the study. He said: "We have to bear in mind that this study can tell us about the association but not about the causation.

"Since the association has barely increased, particularly considering that 80 per cent of us live within two kilometres of a site, I am greatly reassured.

"If a woman asked 'do I have to move away?' I would say no. I am much more concerned about diet, smoking and alcohol."

Steve Lee, the head of waste management and regulations at the Environment Agency, said the common gases found at landfill sites were carbon dioxide and methane and there was "nothing to show" what might have caused abnormalities.

European Union guidelines state that nations have to halve the amount of biodegradable waste disposed of in landfill sites by 2013. But Mike Childs, of Friends of the Earth, said the Government must take further action by increasing the landfill tax, particularly for hazardous waste, and phasing out the burial of toxic waste.

"This study adds to our fears that if you are born near a landfill site you are more likely to be born with a birth defect. Although the authors rightly say we need further research, the Government must not use this as an excuse to delay action," he said.