That lead is toxic and can affect human health has been known for almost as long as it has been used by human beings. However, acceptance of the extent of harm it can cause has a more chequered history.

The US first grappled with federal policies to address lead exposure in the 1950s. But it was only in the 1970s that the country largely banned leaded gasoline and lead-based paint — two of the most ubiquitous sources.

Unsurprisingly, industry strongly opposed these bans and tried to refute the evidence of impacts on health. Nevertheless, the bans stood, and the resulting decades saw a dramatic decline in blood lead levels (BLLs) among Americans.

Mexico also faced an epidemic of lead poisoning, which went unrecognised for a long time. A major source of exposure in Mexico was traditional lead-glazed ceramic-ware — which continues to be widely used to cook and serve food across the country.

Given lead poisoning remains largely asymptomatic at lower levels, there is widespread denial in society and among policymakers that traditional pottery could slowly be poisoning the populace.

The Global South has been relatively late to the scene as is evident by a 2023 report in the Lancet which estimated that the overwhelming majority of children with high blood lead levels today live in LMICs.

India is home to 275 million out of the 800 million children estimated to have high BLLs in 2020. Though this figure is shocking, the Indian academic community, which has been researching lead levels for several decades now, was not surprised.

Genetic susceptibility

Lead’s adverse effects in India were being studied beginning in the 1970s according to an analysis done by NITI Aayog and CSIR-NEERI in 2022. A collaborative study between American and Indian universities in 2005 demonstrated that school children with higher blood lead levels achieved lower IQ scores. It was also one of the earliest studies in the world to look at genetic susceptibility factors of children to the adverse impacts of lead.

It is unfortunate that this early cutting-edge research did not find wider applicability in society beyond scientific journals. Awareness of lead poisoning remains abysmally poor among all sections of Indian society today. Limited systematic data on prevalence, the multiplicity of sources, and the often asymptomatic presentation of steadily increasing BLLs have all contributed to the scale of the problem today, with 1 in 2 Indian children exposed to high levels of lead.

Fortunately, India can learn from the experiences of all countries which have tackled the lead problem.

India already has a comprehensive set of standards for lead content in various products.

However, the enforcement of these regulations has been inconsistent. Strengthening regulatory enforcement is crucial to reducing lead exposure, as the example of the above countries has shown. Our health system must also be prepared to effectively identify and treat cases of lead poisoning.

Raising awareness

Most urgently, we need a concerted effort to raise awareness about the dangers of lead exposure, both among the general public and within specific high-risk communities.

We need a whole-of-society approach, where everyone — from government agencies to businesses, from NGOs to individual citizens — works together to eradicate the scourge of lead.

India is in a unique position here — the scale and complexity of the issue in the country means that other LMICs will be looking to India for best practices and policies. India’s robust medico-scientific infrastructure and innovation capabilities also mean it could be at the forefront of cutting-edge research for tackling the problem in an LMIC.

What is clear though, is that India cannot spend any more time denying or ignoring the problem. Lead poisoning today is one of the biggest public health crises facing our young population, particularly given its aspirations to excel in the global knowledge economy, and it must be addressed at the earliest.

The writer is Distinguished Fellow, Pahle India Foundation, and Hu, Professor, Preventive Medicine, University of Southern California