Editor’s note: This is part 1 of a 2-part series, “Tracking down a poison.” See part 2 here.
NEW YORK CITY — In 1988, turmeric producers in Bangladesh had a problem. The country sits on the world’s largest delta, where three rivers empty into the Bay of Bengal, flooding annually and leaving behind rich soils that farmers depend on. That year, all three rivers reached their peaks within a matter of days, creating a deluge that submerged three quarters of the country and killed at least 2,000 people.
When the floods subsided, farmers found black and soggy turmeric roots — unappealing to prospective buyers, even if the raw spice remained intact.
Turmeric polishers, who prepare the roots for sale, found a solution: a quick polish to smooth the exterior then a dusting of a yellow pigment to enhance the natural color.
They didn’t know the powder was poison. They were adding lead chromate, a toxic material used in paints and plastics for its yellow hue. The practice persisted for decades until research collaborators from Bangladesh and the United States uncovered the problem.
Bangladesh isn’t alone. Investigators have identified lead in spices brought to the United States from Pakistan, Nepal, Morocco, India, Georgia and other countries. Many low- and middle-income countries have laws governing food safety, but lack the resources to monitor and enforce them. Lead is unsafe in any quantity, affecting children most severely with behavioral and developmental delays. An estimated one in three children in the world has lead poisoning from contact with common exposure sources like paints, informal battery recycling centers, cookware, cosmetics and, in some cases, spices, a 2020 report from the United Nations Children’s Fund (UNICEF) and Pure Earth found
Tests for lead poisoning occur rarely in low- and middle-income countries, where cases are clustered, because doctors lack the information and resources to administer them. Yet in Bangladesh and Georgia research that narrowed in on a specific lead-poisoning problem and its source, along with government investment in enforcement, made the difference. Both countries transformed their spice industries to remove poison pigments.
Uncovering a lead exposure problem
In 2018, a study of pregnant women in rural Bangladesh revealed that 31% had elevated blood lead levels. A research team from Stanford University and Bangladesh’s International Centre for Diarrhoeal Disease Research, or icddr had evidence the women were encountering lead in the solder on tin cans, in turmeric roots and in small pieces of clay sometimes chewed during pregnancy. They analyzed each source at its atomic level and found that only the lead in turmeric matched the lead in the women’s blood. That finding led them to the spice supply chain. “We wanted to be very detailed, because there have been a lot of food safety scares in Bangladesh,” Jenna Forsyth, a research scientist at the Stanford School of Medicine, told Environmental Health News (EHN). Debunked reports of fake eggs and plastic in rice had left the public and government skeptical.
Interviews and workshops with turmeric producers revealed that the practice of adding yellow pigment to turmeric roots started with large floods in the 1980s and persisted decades later. Even when the roots weren’t black from wet conditions, the yellow pigment increased profits. Turmeric roots are a duller brown on the outside, and polishing reveals the yellow spice inside, but that means losing weight and earning less for each root. With the lead chromate pigment, polishers could preserve weight and mimic the warm yellow color.
Finding the lead in Georgia
Thousands of miles away, in the country of Georgia, spice mixes containing the regional yellow marigold flower were contaminated with the same lead chromate pigment. Here, instead of a dusting of color, spice packagers added pigment straight into powdered spices, sometimes in enormous quantities.
Health officials noticed the first signs of trouble in New York City. In the state, doctors test all 1- and 2-year-olds for lead and conduct risk assessments until age 6. Whenever a high blood lead level is identified in a child or an adult in New York City, investigators look for the source.
“We identify patterns in the types of consumer products that contain high levels of lead,” Paromita Hore, director of environmental exposure assessment and education at the New York City Department of Health and Mental Hygiene told EHN. “[Data] can identify at-risk communities.”
Her team has found lead in spices from around the world, typically carried from other countries by individuals into New York. Georgian spices repeatedly ranked among the worst offenders, with high quantities of lead. In the worst instance, a spice mix sample taken during an investigation in September 2020 contained 78,000 parts per million of lead, meaning that nearly 8% of the spice was pure lead.
“The solution is fixing the issue in the abroad country,” said Hore, “so one of our approaches is to share our findings with foreign authorities.” The team reached out to the Georgian consulate in 2011 and in 2015.
Continuing to identify lead in spices from Georgia, in 2017 the New York City health department issued a warning for New Yorkers to get a blood lead test if they had eaten spices from the country. News sites in Georgia picked up the story, and the Georgian National Food Agency responded saying the information “ has nothing to do with today’s reality,” and admonished the media for misleading the public, according to a Google translation of a 2017 Facebook post.
Yet a 2015 study of blood lead levels in Georgia had pointed to a bigger problem in the country. It was led by Dr. Ziad Kazzi, a medical toxicologist and emergency medicine professor at Emory University who traveled frequently to Georgia because of a family connection.
“I asked a question about lead in Georgia and I rapidly discovered there was no answer at the time,” Kazzi told EHN. He launched a study of children’s blood lead levels at a hospital in Tbilisi in 2015, and found that many children had levels above five micrograms per decilitre. This level means a case of lead-poisoning, and it causes children to lose about three to five IQ points, according to UNICEF.
The finding motivated the Georgian government to add blood lead testing to a national survey of children’s health. UNICEF coordinates children’s health surveys in developing countries around the world, but they had never included blood lead testing. Most low- and middle-income countries, where the surveys are conducted, don’t have the equipment or experience to test blood samples for lead. In Georgia’s case, the Italian National Institute of Health agreed to test the samples, collected from more than a thousand children around the country in 2018.
The testing revealed that 41% of children in Georgia had lead poisoning. “It was really appalling, nobody expected this,” Abheet Solomon, global program lead on healthy environments for healthy children at UNICEF told EHN. In a region of western Georgia called Ajarra, 80% of children had lead poisoning.
As the Georgian government and UNICEF started outreach and medical care, Bret Ericson, former chief operating officer at Pure Earth, arrived with a research team to root out the source of lead exposures.
The Pure Earth team went to the homes of children who tested exceptionally high for lead, at 30 micrograms per decilitre or more, six times the typical level for serious concern. They brought an expensive handheld machine that could identify lead presence in anything it was pointed at.
Ericson recalls spending hours in the first few houses, scanning every conceivable item and surface. Then he remembered a few studies he read on the plane to Georgia that mentioned spices as a source of lead exposure, and they started testing spices from families’ kitchens.
Particularly in the Ajarra region, “we started getting hit after hit of exceptionally high levels in spices,” Ericson told EHN. “We found one at 25,000 parts per million, that’s poison, and it’s just in some kid’s house, so it’s heart wrenching stuff,” he said.
Pure Earth contacted spice producers to understand how lead ended up in people’s food. They modeled their outreach off of Stanford and the International Centre for Diarrhoeal Disease Research’s work in Bangladesh, Andrew McCartor, executive director of Pure Earth, told EHN.
“We interviewed everyone in the supply chain from the retail vendor in a bazaar to the wholesaler that supplies them to the manufacturer that supplies the wholesaler,” he said. They discovered that the same lead chromate yellow pigment used in Bangladesh was added to spices by people packing them for sale across Georgia.
The yellow marigold flower loses its bright hue as it dries, so packagers added yellow pigment to increase visual appeal and total weight, “There was no real understanding about the threats” from people in the spice industry, Khatuna Akhalaia, Georgia country director for Pure Earth, told EHN.
Getting the lead out
Georgia’s government passed regulations to ban lead in spices, developed their enforcement capacity and began a public health awareness campaign.
Bangladesh already had laws banning lead in food, but a lack of awareness of the problem in turmeric meant it was never enforced. The mountain of data and information published by researchers convinced the government they needed to act.
The Bangladesh Food Safety Authority distributed roughly 50,000 flyers to people in wholesale markets selling turmeric and the public, explaining that lead chromate powder used on turmeric is poisonous and that they’d start enforcing the rules. Like the spice packagers in Georgia, turmeric polishers and wholesalers in Bangladesh weren’t aware of the health dangers.
Producers became “champions” of removing lead from turmeric once they knew about the health risks, said Forsyth. Her team tested blood lead levels of some people working in turmeric production: high levels were found in everyone from the people doing the polishing to business owners more removed from the raw pigment.
After making the industry aware of the rules, the Bangladesh Food Safety Authority entered a spice market in Dhaka in 2019 with testing equipment, a mobile court and a camera crew to make a public example of enforcing the law.
Officials tested turmeric on the spot, and found it in two shops, where they confiscated the roots and issued $9,288 fines. The media picked up the story, and turmeric producers across Bangladesh saw that the lead chromate had to go.
Early signs of success in removing lead
The research team in Bangladesh returned to turmeric producers in 2021. First they tested turmeric in markets, and found no lead in more than 600 samples purchased from dozens of wholesalers in Dhaka, compared to the 47% of samples that contained lead in 2019. They visited turmeric polishing sites where they had previously seen the yellow pigments at 30% of production sites, and this time found no evidence of its presence. Finally, they repeated blood testing of turmeric polishers, finding a 30% drop in blood lead levels.
For children, removing an exposure source can lower their blood lead level and stop the impacts of lead from progressing, but neurological and developmental damage can’t be undone. In the most extreme cases, with a blood lead level above 45 micrograms per decilitre, doctors can use chelating medicine to remove lead from the blood, but it isn’t recommended below that level due to harsh side effects. Good nutrition with sufficient vitamins can help the body absorb less lead while it’s present in the blood.
Turmeric isn’t the only source of lead exposure in Bangladesh. The country has many informal lead acid battery recycling sites, which can expose people to lead through the air and soil surrounding them. But Forsyth is optimistic when it comes to spices. “We’re seeing some exciting results that, indeed, these local levels have declined frankly more than expected,” she said.
Similarly, in Georgia Pure Earth tested samples from markets in 2022 and found no evidence of lead in any spices, reported Akhalaia. She and Md. Mahbubur Rahman, project coordinator at the International Centre for Diarrhoeal Disease Research, both emphasized the importance of continuing strict monitoring.
“When you take action it works, but later on, when people forget, they can turn back to the same position,” Rahman said. Pure Earth Georgia and the International Centre for Diarrhoeal Disease Research continue to monitor spices in their respective countries to stay vigilant for back sliding.
As for New York City, where the lead in Georgian spices was first flagged, Hore and her team are “seeing a 95% decline in the rate of children with Georgian ancestry with elevated blood lead levels,” she said.