Lead exposure: Greater threat to heart health than smoking or cholesterol

New research highlights lead's deadly health impact.

  (photo credit: INGIMAGE)
(photo credit: INGIMAGE)

According to a new study, lead exposure is proving to have a more severe global health impact than previously anticipated, leading to over 5 million deaths each year. This danger is now on par with the threat posed by air pollution. Furthermore, this research suggests that exposure to lead results in young children in developing nations losing nearly six IQ points on average.

The harmful effects of lead contamination on health are well-established, particularly about heart disease and the cognitive development of young children. Consequently, the sale of leaded gasoline has been banned worldwide. However, individuals can still be exposed to this potent neurotoxin through various sources, including food, soil, cookware, fertilizers, cosmetics, lead car batteries, toys, and jewelry.

Lead Study in the Lancet

Two economists from the World Bank, the authors of the study published in the Lancet Planetary Health journal, assert that this research is the first to quantify the impact of lead exposure on heart disease-related deaths and IQ reduction in children across both affluent and developing nations.

Bjorn Larsen, the study's lead author, expressed astonishment at the numbers his model produced, stating, "I didn't even dare to whisper the number because it's so huge."

The model's calculations indicate that in 2019, 5.5 million adults died from heart disease due to lead exposure, with 90 percent of these fatalities occurring in low- and middle-income countries. This figure is six times higher than previous estimates and accounts for approximately 30% of all cardiovascular disease-related deaths, making lead exposure a more significant contributor to heart disease than smoking or high cholesterol, as per Larsen.

Sharp Decline in IQ Due to Lead Exposure

The study also reveals that in 2019, children under five worldwide lost a cumulative total of 765 million IQ points due to lead poisoning. A staggering 95 percent of these cases originated in developing countries, marking an increase of nearly 80 percent compared to previous estimates.

World Bank researchers have estimated the economic cost of lead exposure at $6 trillion in 2019, equivalent to seven percent of the global gross domestic product.Researchers used data on blood lead levels from 183 countries obtained during the 2019 Global Burden of Disease Study to conduct their analysis. Unlike previous studies that primarily focused on lead's effect on blood pressure, this new research investigates how lead impacts the heart, including the hardening of arteries that can lead to strokes.

President of Pure Earth, Richard Fuller, suggests that surveys in developing countries often reveal higher blood lead levels than those estimated in this study, indicating that lead's impact may be even more severe than reported. He emphasizes the need for immediate attention to this issue, referring to it as a "wake-up call."

Larsen acknowledges that there is still much to learn about the different sources of lead contamination contributing to blood lead levels. Fuller points out that a portion of this puzzle was unveiled in a recent Pure Earth report, which analyzed 5,000 consumer products and food samples across 25 developing countries. The findings showed high rates of lead contamination in metal pots and pans, ceramic cookware, paint, cosmetics, and even toys, which Fuller asserts is a significant factor contributing to lead poisoning in impoverished nations, stating, "The kitchen utensils in which they cook the food are the ones that poison them."