Lead author Bjorn Larsen told AFP that when the pair first saw the figure their model calculated, “we didn’t even dare to whisper the number” because it was so “enormous”.
Exposure to a potent toxin lead likely causes 5.5 million cardiovascular diseases linked-premature adult deaths and 765 million lost IQ points among children annually, according to estimates from an article published in Lancet Public Health.
countries to phase lead out of the global economy, which is estimated to generate more than $100 billion in economic value.
“Why are we allowing an industry worth less than $100 billion cause enormous destruction to the biosphere, the food web, public health, social justice and future generations?” the researchers wrote in the paper.
This gain is smaller than the economic losses from premature death from cardiovascular disease and cognitive dysfunction due to lead exposure alone, which cause economic losses of $6 trillion, the study highlighted.
Lead is a heavy metal known to mimic calcium, which is stored in bone. It interrupts metabolic processes in humans, impacting intelligence, and increasing the risk of heart disease, kidney failure and premature death.
“Lead is a remarkably harmful toxin. Even within the context of limited resources, we have to find ways to focus on reducing exposure to it,” Stephen Luby, Professor of Medicine at Stanford University and one of the study’s authors, said in a statement.
Children having blood lead level of 10 microgram per litre (µg/L) suffer a loss of 1 IQ point. Globally, 815 million children are estimated to have blood lead levels greater than 50 µg/L and 413 million children have blood lead levels over 100 µg/L.
While there is no known safe blood lead concentration, even blood lead concentrations as low as 3.5 µg/dL may be associated with decreased intelligence in children, behavioural difficulties and learning problems, according to the World Health Organization.
By 2000, lead was phased out from most gasoline, paint, plumbing and other consumer products. Still, the lead market has seen increasing demand due to low priced lead-acid batteries.
The researchers estimated that 4.5 million metric tons of lead were mined in 2020. If the price of the heavy metal per tonne is $1625, the gross annual revenue from lead mining was approximately $7.3 billion. More than 85 per cent of the lead that is mined or generated through recycling is used to manufacture lead-acid batteries, the paper highlighted.
The heavy metal is toxic to insects, birds and animals as well. They also affect soil microbes.
Considering that the global lead-acid battery business in 2020 was valued at $50 billion, the researchers conservatively estimate that lead-based products contributed less than $100 billion in value to the global economy in 2020.
The researchers, however, added that the full economic costs of lead exposure are far higher, due to the premature death and lost productivity from many other ailments caused by lead exposure and elevated healthcare costs.
While the researchers see value for the world to enter a treaty to eliminate lead mining and sale of lead containing products, they argue that such treaties take years to negotiate. Instead, they said, political authorities can reduce lead use in their own jurisdictions.
Other strategies involve adding progressive tax on lead-based products and subsidies for less toxic alternatives and proposing phase-out date by 2035. This, the paper added, could fuel the development of substitutes.
Even if the world manages to eliminate lead mining and new lead products by 2035, legacy sources of lead will continue to circulate in the economy.
Still, population exposure would progressively decline. In the United States, blood lead levels among children under aged five years declined by 94 per cent 40 years after the Environmental Protection Agency, agency of the US government that sets and enforces national pollution-control standards, began phasing lead out of gasoline.