Lead In Turmeric? Not On Farms, But During Processing: Study

In findings that could bring relief to millions of turmeric growers across the country, a new study has found that lead contamination in turmeric is unlikely to originate on farms, but is more likely to occur after harvest during processing, handling, storage or deliberate adulteration.

The study by environmental research and advocacy organisation ‘Toxics Link’ found that raw turmeric rhizomes collected directly from farms across six States contained lead levels well within the safety limits prescribed by the Food Safety and Standards Authority of India (FSSAI).

The findings shift the focus of food safety concerns from agricultural practices to vulnerabilities in the spice supply chain.

India, the world's largest producer, consumer and exporter of turmeric, depends heavily on the spice not only as a kitchen staple but also as an ingredient in Ayurveda, traditional medicine and religious practices.

The report, Lead in Turmeric, analysed 13 raw turmeric samples collected from farms in Maharashtra, Telangana, Tamil Nadu, Odisha, Karnataka and Madhya Pradesh. The samples were tested in an NABL-accredited laboratory using Inductively Coupled Plasma Mass Spectrometry (ICP-MS), one of the most sensitive analytical methods for detecting heavy metals.

Lead concentrations ranged from below the laboratory's limit of quantification (0.05 mg/kg) to 1.87 mg/kg—well below the FSSAI's maximum permissible limit of 10 mg/kg for turmeric.

The findings suggest that naturally cultivated turmeric contains only background levels of lead, reinforcing evidence that the high concentrations detected in some commercially available turmeric powders are introduced later in the supply chain rather than absorbed from the soil during cultivation.

Researchers point to post-harvest contamination through processing, grinding, storage and packaging, or deliberate adulteration with lead chromate, an industrial chemical illegally used to enhance turmeric's bright yellow colour and improve its market value.

The issue has drawn increasing global attention in recent years. International investigations have reported dangerously high lead concentrations in turmeric sold in parts of South Asia, with some samples containing lead chromate at levels several times higher than permissible limits. Such incidents have triggered food safety alerts and raised concerns about India's spice exports and consumer confidence in international markets.

The study also comes amid heightened attention to food contamination following a series of regulatory actions by Indian authorities against unsafe or adulterated food products.

Lead exposure remains one of the most serious environmental health risks worldwide. The World Health Organization (WHO) states that there is no safe level of lead exposure, particularly for children. Even small amounts can permanently affect brain development, reduce intelligence quotient (IQ), impair learning ability and cause behavioural disorders. Long-term exposure is also associated with kidney damage, cardiovascular disease, anaemia, reproductive disorders and adverse pregnancy outcomes.

Commenting on the findings, Satish Sinha, Associate Director, Toxics Link, said, "Our findings indicate that turmeric cultivated on farms generally complies with existing food safety standards for lead. The evidence points towards contamination occurring after harvest, making it imperative to strengthen surveillance and regulatory oversight across processing, packaging, and marketing stages."

He added, "Protecting consumers requires greater traceability throughout the supply chain and strict enforcement against food adulteration."

The report notes that although environmental contamination through soil, irrigation water, industrial emissions and agricultural inputs has often been considered a possible source of heavy metals, the present study found little evidence that these factors significantly contribute to lead levels in raw turmeric. Instead, it identifies post-harvest handling as the critical stage requiring regulatory attention.

Based on its findings, Toxics Link has urged the FSSAI and State food safety authorities to strengthen routine surveillance of turmeric and other spices sold in wholesale and retail markets.

It has also recommended improving traceability throughout the supply chain, conducting targeted inspections of processing and packaging units, and taking stringent action against deliberate adulteration.

The organisation has further called for larger multi-State studies incorporating soil, irrigation water, agricultural inputs and processing facilities to better understand contamination pathways and strengthen food safety governance.

Experts say such investigations are essential because India accounts for nearly 80 per cent of global turmeric production and exports substantial quantities to international markets, where food safety standards are becoming increasingly stringent.