Researchers find lead in turmeric

Stanford researchers find lead in turmeric
A merchant displays powdered and whole spices, including turmeric in the Karwan Bazar of Dhaka, Bangladesh. Credit: Abir Abdullah/Asian Development Bank

It's billed as a health booster and healing agent, but it may be the source of cognitive defects and other severe ailments. A new Stanford-led study reveals that turmeric—a commonly used spice throughout South Asia—is sometimes adulterated with a lead-laced chemical compound in Bangladesh, one of the world's predominant turmeric-growing regions.

Long banned from , is a considered unsafe in any quantity. A related analysis published recently confirms for the first time that is likely the primary contributor to elevated blood lead levels among Bangladeshis surveyed.

"People are unknowingly consuming something that could cause major health issues," said the papers' lead author Jenna Forsyth, a postdoctoral scholar at the Stanford Woods Institute for the Environment. "We know adulterated turmeric is a source of lead exposure, and we have to do something about it."

A longstanding problem

The first study, available online in Environmental Research, involves a range of analyses, including interviews with farmers and spice processors in several Bangladesh's districts, which together produce nearly half of the nation's turmeric. Many traced the issue to the 1980s when a massive flood left turmeric crops wet and relatively dull in color. Demand for bright yellow curry led turmeric processors to add lead chromate—an industrial yellow pigment commonly used to color toys and furniture—to their product. The practice continued as a cheap, fast way to produce a desirable color.

Potent neurotoxin

As a potent neurotoxin, lead increases the risk of heart and brain disease in adults and interferes with children's brain development. About 90 percent of children with elevated blood lead levels live in lower-income countries, and resulting cognitive damages are associated with nearly one trillion dollars in lost productivity annually.

"Unlike other metals, there is no safe consumption limit for lead, it's a neurotoxin in its totality," said the papers' senior author Stephen Luby, professor of medicine and the director of research for Stanford's Center for Innovation in Global Health. "We cannot console ourselves proposing that if the contamination were down to such and such level, it would have been safe."

The related study, published Sept. 17 in Environmental Science & Technology, looked at various potential sources of blood lead level contamination in Bangladeshis. Lead comes in various forms, called isotopes, and the ratios of those isotopes vary by the lead's origin. The researchers were able to fingerprint lead chromate-adulterated turmeric as the most likely culprit by matching it to lead isotopes in people's blood. The research is the first to directly link lead in turmeric to lead levels in blood.

Beyond Bangladesh

The researchers did not find direct evidence of contaminated turmeric beyond Bangladesh, and they point out that food safety checks by importing countries have incentivized large-scale Bangladesh spice processors to limit the amount of lead added to turmeric destined for export. However, the researchers caution, "the current system of periodic food safety checks may catch only a fraction of the adulterated turmeric being traded worldwide." In fact, since 2011, more than 15 brands of turmeric—distributed to countries including the U.S. - have been recalled due to excessive levels of lead.

While these recalls and previous studies found the presence of lead in turmeric, none clearly identified the source (some suggested it might be linked to soil contamination), proved the link to blood lead levels or revealed the problem's pervasiveness and incentives perpetuating it.

Toward solutions

Since 2014, Forsyth, Luby and Scott Fendorf, the Terry Huffington Professor in Stanford's School of Earth, Energy and Environment—co-authors on both papers—have worked in rural Bangladesh to assess lead exposure. With funding from the Stanford Woods Institute for the Environment, they first conducted a population assessment that found more than 30 percent of pregnant women had elevated .

The researchers now plan to focus on shifting consumer behaviors away from eating contaminated turmeric and reducing incentives for the practice. They suggest more effective and efficient drying technologies for turmeric processing. They also recommend that import inspectors around the world screen turmeric with X-ray devices that can detect lead and other chemicals.

Although few low-cost answers seem readily available in Bangladesh, the researchers suggest engaging consumers, producers and other stakeholders focused on food safety and public health could provide the seeds of a solution. To that end, Forsyth, Luby and Fendorf are part of an interdisciplinary project team, funded by the Stanford King Center on Global Development, seeking solutions to reduce lead exposure from turmeric, battery recycling and other sources in Bangladesh and beyond.

Among other goals, the team plans to develop business opportunities that reduce lead exposure. One team member, bioengineer Manu Prakash, is developing low-cost technologies to measure lead in turmeric, blood and other sources. Other collaborators, Shilajeet Banerjee and Erica Plambeck, are studying ways to shift demand and create business opportunities for lead-free turmeric.

"Jenna's remarkable work allows us to collaborate with stakeholders in Bangladesh to target effective prevention," Luby said.


Explore further

Are there health benefits to taking turmeric?

More information: Jenna E. Forsyth et al, Turmeric means "yellow" in Bengali: Lead chromate pigments added to turmeric threaten public health across Bangladesh, Environmental Research (2019). DOI: 10.1016/j.envres.2019.108722
Journal information: Environmental Research

Citation: Researchers find lead in turmeric (2019, September 24) retrieved 20 October 2019 from https://phys.org/news/2019-09-turmeric.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
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User comments

Sep 24, 2019
What an effing, clickbait headline.

Sep 24, 2019
so, auntie
where is your proof for your comment?
i mean, you wouldn't denounce empirical evidence out of sheer ignorant spite, would you?

yeah, that's a rhetorical question

perhaps you might lay off consuming the turmeric for a while?
go to your doctor, get tested for lead poisoning
perhaps chelating drugs might prevent further deterioration of your cerebral functions?

Sep 24, 2019
Well, willis, the headline gives the impression that lead is naturally occurring in turmeric. So, rather than a headline that reflects the text, such as -- Researchers find turmeric laced with lead. They went with that clickbait.

There is scientific evidence that turmeric boosts brain function, and I would recommend it to you, but then that would require you to have a brain, to get any benefit.

Sep 24, 2019
oh, poor auntie oral
she is unable to cognate that it does not matter, to the uninformed consumer how the supply of turmeric is contaminated
what does matter to the consumer?
is how much of the product that are purchasing for consumption is contaminated with lead

you implied that you are consuming large quantities of turmeric?
i seriously urge you to get tested for lead poisoning

this is a global criminal enterprise
there are large profits in selling & reselling counterfeit (cinnamon, wine, entertainment )
contaminated (decorative ceramics, bottled water)
defective production runs
American pharmaceuticals
both China's cheap consumer goods)
& most especially obsolete weaponry & polluting waste

auntie oral, you are just one more chump
of piously predatory greed
out of billions of other victims

what?

oh, you thought you were one of the entitled predators?

what an ice-cold bucket of polluted water on your self-delusion of majesty

Sep 24, 2019
you implied that you are consuming large quantities of turmeric?

Oh, brainless willissss..
aren't you the silliest
lacking the benefits of turmeric, you can't see
it is your stupidity that has implicated me
in your insanity
In no way or form, have I implied
my level of consumption, and so you lied
Thus, beyond your capacity to know
sourced from the roots of plants that grow
to what end would these be lead laced
and then be made available for purchase

So, go take your meds and rest a bit
and give us a reprieve from you talking shit.


Sep 24, 2019
@antigoracle.
What an effing, clickbait headline.
In this instance I have to agree with you, mate! I too immediately inferred from that headline that the lead was inherent in the Turmeric, and not a result of processing shenanigans as the article goes on to explain. Whoever came up with that headline should be castigated severely for unnecessarily upsetting casual skimmers of the news headlines who may not have had time to thoroughly read the article itself right away. Bad TITLE editors!

Sep 24, 2019
so auntie, you are not denying regularly dosing yourself with possibly toxic doses of turmeric?

it explains a lot of your incoherent rants
& if you are not purchasing it?
it would be no surprise to your audience to discover you were pilfering your supply from a store

you claim to grow it in sand?
i would wonder at your source of that sand
perhaps a midnight requisition from a neighboring sandbox?
supplying yourself with an extra ration of catshit

you oughta get that sand tested
might sober you up a bit?

Sep 24, 2019
Well willis, please enlighten me. What is a possible toxic dose of turmeric?

Sep 24, 2019
"A new Stanford-led study reveals that turmeric—a commonly used spice throughout South Asia—is sometimes adulterated with a lead-laced chemical compound in Bangladesh, one of the world's predominant turmeric-growing regions."

and

"Many traced the issue to the 1980s when a massive flood left turmeric crops wet and relatively dull in color. Demand for bright yellow curry led turmeric processors to add lead chromate—an industrial yellow pigment commonly used to color toys and furniture—to their product. The practice continued as a cheap, fast way to produce a desirable color."

So it was the consumers themselves who demanded the turmeric they bought should be a bright yellow colour, rather than a washed-out appearance. And the processors gave the consumers what they wanted - a bright yellow colour. The commercial value of appearance of the product motivates fraudulent practices sometimes. And in this case, the fraud affects the brains of the consumer.

Sep 24, 2019
If your feeling peckish
and adventurous
Holland & Barrett Organic High Strength Turmeric with Black Pepper 90 Capsules 600mg
Native to South East Asia, the turmeric plant has been used for thousands of years as both a cooking spice and a natural aid. It's part of the Zingiberaceae family, which also includes ginger
Just look out for that bright yellow colour

Zingiberaceae or the ginger family is a family of flowering plants made up of about 50 genera with a total of about 1600 known species of aromatic perennial herbs with creeping horizontal or tuberous rhizomes distributed throughout tropical Africa, Asia, and the Americas
https://en.wikipe...beraceae

Sep 24, 2019
Headline partially correct. 'Bangladesh' missing from the title.

Sep 24, 2019
So it was the consumers themselves who demanded the turmeric they bought should be a bright yellow colour, rather than a washed-out appearance.
On my planet, an unexpected color often signals lower quality or even dangerous condition of food. It sounds to me like the customers were demanding normal quality, which is normal consumer behavior, and it's not relevant to bring normal consumer behavior into an issue of supplier fraud.

Sep 24, 2019
There are reasonable historical researchers who think the use of lead pipes was the downfall of the Roman empire.

Just sayin'.

Sep 25, 2019
So it was the consumers themselves who demanded the turmeric they bought should be a bright yellow colour, rather than a washed-out appearance.
On my planet, an unexpected color often signals lower quality or even dangerous condition of food. It sounds to me like the customers were demanding normal quality, which is normal consumer behavior, and it's not relevant to bring normal consumer behavior into an issue of supplier fraud.
says ddaye

But, you see, if the consumers/customers hadn't demanded that the turmeric should be a bright, yellow colour, then the merchant would not have gone to the trouble of changing the whitish colour of the turmeric (after the flood) into the colour that the customers wanted. It is a small matter of "supply and demand". Else the merchant would have lost his customers, as well as his revenue and means of earning a living. He gave them what they demanded, and possibly wasn't aware that lead was included for the price.

Sep 25, 2019
So you just explained why they did it, which we all understood. Does that mean it's justified in your mind?

The merchant losing their means of making a living is an embellishment by you. The price would be lower and profits would be less for that particular batch.

Sep 25, 2019
But, you see, if the consumers/customers hadn't demanded that the turmeric should be a bright, yellow colour, then the merchant would not have gone to the trouble of changing the whitish colour of the turmeric (after the flood) into the colour that the customers wanted. It is a small matter of "supply and demand". Else the merchant would have lost his customers, as well as his revenue and means of earning a living. He gave them what they demanded, and possibly wasn't aware that lead was included for the price
IOW pussytard the serial flooder under multiple socks says this is obviously the consumer's fault because they asked for it, which is why she drinks wood alcohol and feeds her dog melamine. "They're cheap - so what?" she drools as she gums her sweet sorghum sandwich while having sex up against the microwave. And another one of her many miscarriages.

Maybe your diet is why you have so many miscarriages, have you ever considered this pussytard? TiO2 by the spoonful-

Sep 25, 2019

Oh, brainless willissss..
aren't you the silliest
lacking the benefits of turmeric, you can't see
it is your stupidity that has implicated me
in your insanity
In no way or form, have I implied
my level of consumption, and so you lied
Thus, beyond your capacity to know
sourced from the roots of plants that grow
to what end would these be lead laced
and then be made available for purchase

So, go take your meds and rest a bit
and give us a reprieve from you talking shit.

So great post and a poem that all I can say is raise my hat! Wonderful!

Sep 25, 2019
The way I understood this issue (which has been around for a long time) is not that lead gives the desired color but that spices are sold by weight. Adding this particular lead isotope - which just happens to have the correct color to be passed off as tumeric - adds a lot of cheap weight.

Sep 25, 2019
Adding this particular lead isotope - which just happens to have the correct color to be passed off as tumeric - adds a lot of cheap weight.
That's pretty disgusting. We'll see what happens to the turmeric market as a result. This could be pretty drastic, in a small-market sort of way.

Sep 25, 2019
The way I understood this issue (which has been around for a long time) is not that lead gives the desired color but that spices are sold by weight. Adding this particular lead isotope - which just happens to have the correct color to be passed off as tumeric - adds a lot of cheap weight.
Now that makes more sense -- the article's narrative begs the question of why not just use a safer food coloring.

https://www.youtu...jZoRtu0Y
"No one on the corner has swagg like us
hit me on my burner prepaid wireless..."

Sep 25, 2019
That's pretty disgusting. We'll see what happens to the turmeric market as a result. This could be pretty drastic, in a small-market sort of way.

Nothing will happen. This practice has been known for many years.

Sep 25, 2019
so?
the victims of criminal activities are to be blamed for the consequences?

that the victims are to be found guilty for allowing themselves to be preyed upon?

with pious prayers by the fakirs, i'm sure

after all, the unscrupulous can't just pass up the lucre

how very trump of you...

Sep 25, 2019
This report reveals a disgusting and dangerous practice, but, it's in faraway Bangladesh.
So, how about what's in your food -
Artificial Sweeteners. Aspartame, (E951) more popularly known as Nutrasweet and Equal, is often found in foods labeled "diet" or "sugar free". ...
High Fructose Corn Syrup. ...
Monosodium Glutamate (MSG / E621) ...
Trans Fat. ...
Common Food Dyes. ...
Sodium Sulfite (E221) ...
Sodium Nitrate/Sodium Nitrite. ...
BHA and BHT (E320)
http://www.hungry...to-avoid

Sep 25, 2019
That's pretty disgusting. We'll see what happens to the turmeric market as a result
"Evidence of Turmeric Contamination With Lead in the United States
"In 2010, a report in Pediatrics detailed the case of a 12-month-old boy who was referred to the Pediatric Environmental Health Center at Boston Children's Hospital with a blood lead level of 28 μg/dL,3 which exceeded the Centers for Disease Control and Prevention's reference level of 5 μg/dL.4 After conducting a detailed investigation of the child's home, the Massachusetts Department of Public Health determined that daily consumption of several lead-contaminated spices, including turmeric, was the primary pathway of exposure.3 Between 2010 and 2014, five other cases of childhood lead poisoning attributable to culinary spice consumption were reported in the United States."

-uh nothing?

Sep 25, 2019
which freakin' woomonger sold that child's parents on feeding spices into the diet of an infant anyway?
if the kid ain't crapping it's diapers enough to your satisfaction?
see a pediatrician!

though these home schooled / church educated parents probably lack the smarts to follow a doctor's instructions

that's almost as bad as feeding an infant, unfiltered raw honey
& no, cooking it ain't going to reduce the botulism spores

Sep 25, 2019
which freakin' woomonger sold that child's parents on feeding spices into the diet of an infant anyway?
if the kid ain't crapping it's diapers enough to your satisfaction?

Well, willis, only to the ignorant Westerner does turmeric/curcumin remain, just a spice. Since, modern medicine is still discovering its health benefits.
At least you ain't crapping your diapers, you use the forum for that.

Sep 25, 2019
all my life. i've been warned
"don't eat that"
"don't eat everything on your plate"
"take these supplements"
"eat more of these,
eat less of those"
"don't drink THAT!"
"drink more water,
drink less coffee"
"eat more chocolate;
eat less chocolate"

& everyone of those smarmy health-food addicts i have endured?

are dead & buried

& i have to keep suffering on, indulging my gluttony

Sep 26, 2019

The American Spice Trade Association's Statement on Lead in Turmeric:
https://www.astas...urmeric/

Lead in Spices, Herbal Remedies, and Ceremonial Powders Sampled from Home Investigations for Children with Elevated Blood Lead Levels — North Carolina, 2011–2018
https://www.cdc.g...6746a2_e

Lead is most dangerous for children.

Sep 26, 2019
Is Turmeric in Ireland?

Sep 26, 2019
must get pretty boring eating plain old spuds all the time?

Oct 01, 2019
Just threw away all my turmeric.

To be honest I never liked that lead chromate aftertaste.

Oct 01, 2019
By the way can you get me an estimate on the number of health conscious folks who ate turmeric regularly for the 'anti-oxidants' ... estimate number of IQ points lost

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