A public concern

For months before his second birthday in 2007, Vijay Singh (name changed) had frequent bouts of uncontrolled vomiting three-four times a day. He had turned pale and weak. For almost a year, Vijay’s parents, residents of Barabanki town in Uttar Pradesh, took him to several medical centres. Finally, a doctor at the district hospital in Faizabad, realised Vijay was severely anaemic and began blood transfusions. Even so, his haemoglobin levels remained dangerously low.

Till today, his blood lead level hovers around 50 µg/dL, but he does not show any obvious signs of lead toxicity like weakness or poor physical growth.

An ongoing crisis

Lead poisoning is not a new concern. For more than a century, scientists have been aware that the naturally occurring metal has no biological function that can benefit the human body but can cause devastating physical and developmental impacts.

However, despite the awareness, lead toxicity continues to be a public health concern. Half the children in India report high blood lead levels, reveals a 2020 report by the UN Children’s Fund (UNICEF) and Pure Earth, a US-based environmental health non-profit. The report says 275 million children in India record blood lead levels beyond the tolerable limit of 5 µg/dL. Of these, 64.3 million children’s blood lead levels exceed 10 µg/dL.

In terms of average blood lead levels among the population, some 23 states exceed the 5 µg/dL margin; levels in the remaining 13 states and Union Territories cannot be determined as there is a lack of research and screening mechanisms to collect data.

Lead toxicity is not just a concern in India. The UNICEF-Pure Earth report notes around one in three children worldwide record blood lead levels of over 5 µg/dL. Countries with this burden include Iran, Afghanistan, Yemen, Peru, Vietnam, the Philippines and parts of Central Africa.

Debilitating impacts

The adverse impacts of lead entering the human body have been known since 1920. “The Industrial Revolution caused an epidemic of metal intoxication, urging scientists and physicians of that period to study and identify specific symptoms and organ alterations related to chronic lead poisoning,” says a 2012 study published in the journal Safety and Health at Work by researchers from Italy.

In a newborn, lead poisoning can result in premature birth, low birth weight and slow growth. In children and adults, it can cause anaemia as well as neurological, skeletal and neuromuscular illnesses. The UNICEF-Pure Earth report says children with elevated blood lead levels scored three-five points lower on intelligence tests. This “permanent damage (affects) a child’s brain development and central nervous system, (causing) reduced intelligence, attention deficit disorders and lower educational attainment,” the report notes. This can lead to long-term impacts such as loss of economic productivity.

Present everywhere

Science is clear on the impacts of lead toxicity and research indicates that a significant part of the population is affected. Why then, does the disease continue to remain widespread?

In India, it could be due to the fact that lead does not get as much attention as other potential public health concerns. First of all, the country lacks systems to screen populations for possible exposure. India has some 48 national referral centres for lead projects where blood lead levels can be tested, but screening is usually done on a voluntary basis or at health camps by non-profits.

A study identified 'leaded petrol' as a key source. India had already begun phasing out leaded fuel in 1994, first by introducing low-lead petrol and then by mandating the use of unleaded fuel in April 2000.

Other countries such as the UK took similar steps, which resulted in a decline in deaths associated with lead exposure. India, in contrast, has recorded a 21 per cent increase in deaths caused by lead exposure since 1990.

According to the NITI Aayog-CSIR report, some common occupational and non-occupational sources of lead may be present all around people.

There are measures to protect workers from toxic metal exposure under the Occupational Safety and Health Administration (OSHA) Regulations. However, since the implementation of these norms is voluntary and there is no inspection agency, regulation exists only on paper. Similarly, though the Factories Act, 1948, also has provisions to protect the health and safety of workers, it is difficult to cover all industries.

One lesser-known occupation in the report is “battery work”. Management of lead-acid batteries came under the Batteries (Management and Handling) Rules, 2001. But enforcement capacity to ensure safe and environmentally sound recycling has been inadequate.

In 2022, the Union Ministry of Environment, Forest and Climate Change notified the Battery Waste Management Rules, 2022. The new rules aimed at reducing the share of battery recycling in the informal sector and stressed extended producer responsibility. It remains to be seen whether the government can successfully implement this.

Around this time, the country initiated a phaseout of lead-based paints. But even then, small and medium-scale manufacturers continue to record high levels of lead in their paints; some 31 per cent of household paints had lead concentrations of more than 10,000 PPM, as per information in the NITI Aayog-CSIR report.

Another common source is food. As of now, spices are the only identified sources of lead poisoning, as per experts. In northeastern states, the high moisture content does not allow for turmeric in the region to dry quickly, resulting in a lighter colour. This turmeric is transported to Bihar and West Bengal, where lead is added to the commodity to bring out a deeper yellow colour.

The Food Safety and Standards (Food Products Standards and Food Additives) Regulations, 2011, says the threshold for lead in food of 10 PPM. However, a 2014 study, published in the International Journal of Current Medical And Applied Science notes that among spice samples collected from local markets in Kolkata, “the highest levels of lead was found in chilli powder and turmeric powder, which greatly exceeded the permissible amounts.” There is a need to study the potential presence of lead in other foods.

How to fight this?

Regular screening and testing of lead sources will inform about region-wise prevalence and help tailor interventions, such as “regulations and enforcement, changes in industry practices, training of government officials to assess lead contamination, and changes in public education and consumer behaviour.

We must also enhance the capacity for testing, currently done for blood lead levels. This test only shows how much (lead) is present in circulating blood and not how much is stored in the body.

The final tool is public awareness. We need to devise strategies on a state level, through regional bureaucracy, local press and vernacular language to have a tangible impact. DTE

Views expressed are personal