Medicine

Lead exposure increases risk for premature deaths & cardiovascular diseases

Lead exposure increases risk for premature deaths & cardiovascular diseases

"Our study calls into question the assumption that specific toxicants, like lead, have "safe levels", and suggests that low-level environmental lead exposure is a leading risk factor for premature death in the U.S., particularly from cardiovascular disease", Professor Lanphear said.

There are regulations in place to safeguard people against lead exposure but about 90 percent of US are still exposed to the contaminant, CNN noted.

"In other words, they aren't saying that current exposure to lead in the environment is the main thing here, as much of the exposure would have been in the past when regulation was much less strict than it is now". The results from the study said that low-levels of lead exposure, between one and five micrograms per decilitre of blood, can increase the risk of premature death.

For this latest research, Prof.

Lanphear analyzed earlier United States government research from the National Health and Nutrition Examination Survey (NHANES). Lanphear and his team sought to determine how exposure to lead contributes to all-cause mortality and cardiovascular disease (CVD) mortality in the U.S.

The new Lancet study estimates that deaths from lead exposure approach the levels attributable to smoking, which kills 483,000 Americans each year.

Subjects were enrolled in the study between 1988 and 1994.

At the outset, the average level of lead found in the participants' blood was 2.7 µg/dL, but ranged from less than 1 to 56 µg/dL.

Professor Kevin McConway, Emeritus Professor of Applied Statistics at the Open University, said: "The researchers make a very important point in their report - that it is more accurate to view this study as estimating how many deaths might have been prevented if historical exposures to lead had not occurred".

These figures are nearly 10 times higher than previously estimated in a report by the Institute for Health Metrics and Evaluation at the University of Washington in Seattle, CNN reported.




More than 4,400 people died in the period - and the tenth with the highest level of lead in their blood were 37 per cent more likely to be among them than the tenth with the least.

Using these data, the team calculated that blood lead levels higher than 1 μg/dL are responsible for around 412,000 deaths in the USA each year.

These subjects were also 70 percent more likely to die from CVD, and their risk of death from heart disease was doubled. Of these, around 256,000 are from CVD.

Professor Lanphear said: "Our study calls into question the assumption that specific toxicants like lead have "safe levels" and suggests that low-level environmental lead exposure is a leading risk factor for premature death".

These results were adjusted for age, sex, household income, ethnic origin, diabetes, BMI, smoking status, alcohol consumption, diet, physical activity, and amount of cadmium in urine.

Of environmental lead exposure, he said: "If we took that seriously, without knowing anything more about genetics, without any more expensive drugs, we could much more strategically reduce deaths from heart disease, which is pretty hopeful, actually".

Are there any "safe levels" of toxicants?

"Public health measures", he goes on, "such as abating older housing, phasing out lead-containing jet fuels, replacing lead-plumbing lines, and reducing emissions from smelters and lead battery facilities, will be vital to prevent lead exposure".

Additionally, they note that they could not control for exposure to other contaminants that might affect cardiovascular health, such as arsenic or air pollution.

The authors note some limitations, including that their results rely on one blood lead test taken at the start of the study and therefore can not determine any effect of further lead exposure after the study outset.