Researchers at the World Bank have presented evidence which suggests that lead exposure may be a deadlier culprit for heart disease deaths than even smoking or poor diets.
The analysis was based on data from the 2019 Global Burden of Disease study, including estimates of blood lead levels in 183 countries.
The study simulated the number of heart disease deaths attributable to lead, concluding that approximately 5.5 million deaths worldwide could be linked to the toxic metal. This number starkly contrasts the 2 million deaths attributed to smoking and the 2.6 million from high cholesterol.
“Although global lead exposure has declined substantially since the phasing out of leaded gasoline, sources of lead exposure remain plentiful, especially in low-income and middle-income countries,” wrote the study authors. “Lead is one of WHO’s ten chemicals of major public health concern.”
Lead finds its way into our drinking water from aging infrastructure. Service pipes connecting homes to water mains made out of the heavy metal primarily cause this. Houses in Florida, followed by Illinois and Ohio, are at the highest risk.
Lead is notorious for its cumulative toxicity. Over time, it can cause an array of heart problems by instigating high blood pressure and interfering with nerve functions leading to arrhythmias.
It does this by causing blood vessels to constrict and by impairing kidney function. High blood pressure then exacerbates heart problems by putting additional strain on the heart and contributing to arterial damage.
For young children and infants, the risks are even greater. Lead can severely impact brain and central nervous system development. This results in issues like speech problems, language difficulties, and developmental delays.
“Our findings suggest that global lead exposure has health and economic costs at par with PM2·5 air pollution,” wrote the study authors.
For example, lead exposure is causing children in developing nations to lose an average of six IQ points. This alarming number is six times higher than previous estimates. The epidemic carries an estimated global economic toll of $6 trillion annually.
The research has ignited varied reactions. Environmental economist and study lead author Bjorn Larsen expressed his astonishment at the figures.
Larsen told AFP that when the researchers first saw the figure their model calculated, “we didn’t even dare to whisper the number” because it was so “enormous.”
Richard Fuller, president of Pure Earth, said that in developing countries, previous surveys had mostly found higher blood lead levels than what has been estimated by World Bank. He emphasized that the study is a dire “wake-up call” to the global community.
Yet, skepticism remains. Notably, Dr. Roy Harrison from the University of Birmingham raised concerns regarding the model’s applicability on a global scale. He told AFP the research is “interesting, but subject to many uncertainties.”
The revelations from this study have spurred essential discussions about the quality of drinking water and the potential dangers. Health officials hope that authorities will take the necessary steps to address this global threat to human health.
The study is published in the journal The Lancet Planetary Health.
Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates.