Lead exposures are linked to more deaths than common infectious diseases including Tuberculosis (TB), Malaria and HIV/AIDS.
Lead is a Major Cause of Mortality
Lead stands alone among common hazardous chemicals in both its ubiquity and its impact on public health. Although the effects of lead exposure on children’s development, intellectual capacity and behavior are well-known, there is considerably less awareness of the huge contribution that these exposures have on mortality.
The Institute for Health Metrics and Evaluation (IHME) has estimated the number of deaths from lead and other chemical exposures. Due to lead’s impact on blood pressure and resulting increase in heart attacks and stroke, lead has emerged as the principal chemical killer resulting in more than 1.5 million deaths per year.
In contrast to other well-known global killers, this number exceeds annual deaths from Tuberculosis (TB), Malaria, HIV/AIDS and nutritional deficiencies (see figure below). As exposures to lead are generally much greater in low and middle-income countries, the great majority of these deaths occur in those countries. At the same time, global health spending on lead poisoning prevention represents less than 0.0003% of the approximately $30 billion dollars a year spent on TB, Malaria and HIV/AIDS.
How reliable are these estimates?
The hazards of lead exposure have been more extensively studied than any other toxicant which has resulted in more than 28,000 publications in the peer-reviewed literature. Multiple studies have demonstrated the impact of lead on blood pressure, heart attacks and stroke. Estimates of global deaths linked to these exposures vary with a 2023 study by the World Bank reporting that the more than 5.5 million adults died from cardiovascular disease due to lead exposure.
Silica Dust is a Major Cause of Lung Disease and Death
The hazard of breathing silica dust in mining and other trades has been understood for centuries. However, these exposures are generally uncontrolled in informal sector mining, quarrying, stone crushing, ore processing and construction sites around the world. It is estimated that there are 45 million self-employed artisanal miners in more than 75 mostly low and middle-income countries. It is anticipated that the growth in mining needed for the “green energy transition” will also result in significant increase in artisanal mining.
The resulting burden of disease from unmitigated dust exposure in informal workplaces is not well studied. However recent studies documenting TB, silicosis and lung disease among informal miners demonstrates that silica dust exposures and health outcomes are significantly worse than what has been experienced in industrial mining. Consider, for example, these impacts:
In Malawi informal miners 50% more likely to develop TB than industrial miners;
In Ghana informal miners had a 2.5 times greater TB prevalence than background; and
Informal miners in Zimbabwe had a 34 times greater TB prevalence than background rates in the general population and 19% had silicosis.
These exposures are responsible for death and disease that is ravaging mining communities. However, our research conducted over the past 20 years has demonstrated that low-cost dust controls can be highly effective in significantly reducing respirable silica dust concentrations and lowering the risk of disease.