New estimates suggest that 256000 premature deaths from cardiovascular disease – including 185000 deaths from ischemic heart disease – in the USA may be linked to historical lead exposure in middle-aged and older adults (people currently aged 44 years or over), according to an observational study following 14300 people for almost 20 years, published in The Lancet Public Health journal.
Previous estimates, which assumed that low-level lead exposure did not increase the risk of premature death, produced substantially fewer deaths. However, this new study finds that low-level lead exposure (between 1-5 micrograms of lead per decilitre of blood) increases the risk of premature death, especially from cardiovascular disease. Lead exposure is linked to high blood pressure, hardening of the arteries and ischemic (coronary) heart disease.
Exposure occurs from lead that remains in the environment from historic use in fuel, paint and plumbing, as well as ongoing exposures from foods, emissions from industrial sources, and contamination from lead smelting sites and lead batteries.
This study is the first to estimate the number of deaths in the United States from low-level lead exposure using a nationally-representative sample.
“Our study estimates the impact of historical lead exposure on adults currently aged 44 years old or over in the USA, whose exposure to lead occurred in the years before the study began,” says lead author Professor Bruce Lanphear, Simon Fraser University, Canada.
“Today, lead exposure is much lower because of regulations banning the use of lead in petrol, paints and other consumer products, so the number of deaths from lead exposure will be lower in younger generations. Still, lead represents a leading cause of disease and death, and it is important to continue our efforts to reduce environmental lead exposure.”