Lead and Cadmium found in chocolat

[DirtMechanic]

Now how do these metals get into chocolate? Does anyone know if the plant could be the source? Consumer Reports is said to be the reporter in this article;

Consumer Reports Found Lead In Dark Chocolate From Trader Joe's, Lindt, And More - Tasting Table

If you like dark chocolate, you're not going to like the findings of a new study that looked at lead and cadmium levels in popular dark chocolate bars.

www.tastingtable.com

This source article has a lot of answers and context. Still bothersome to me.

Lead and Cadmium Could Be in Your Dark Chocolate - Consumer Reports

Consumer Reports tested 28 dark chocolate bars and found cadmium and lead in all of them. Here's how to limit your heavy metal exposure.

www.consumerreports.org

 

[YumYum]

It is my understanding that in order for a plant to uptake a nutrient, it has to be in a water soluble form. Elemental lead is not water soluble so can not be taken in by plants but I don't know if plain elemental lead is just laying around in the ground. It is most likely bound to some other mineral which may or may not be water soluble. There are water soluble forms of lead along and the same thing is true with cadmium and probably other heavy metals.

I'm guessing the irrigation water is the culprit by being contaminated or at least slightly contaminated and builds up forms of heavy metals in the soil every time it is irrigated and would be worser during times of drought. Here is an article about water systems containing lead written in 2016.

If the Maine Elementary School was found to be 42 times higher than the acceptable level of 15 ppb in drinking water, that would be 630 ppb (0.63 ppm) of lead in drinking water. A gallon of that water would contain 2.4 mg of lead.
water weight per gallon 3,778,425 mg * 0.63 ppm / 1,000,000 = 2.4 mg
So if you drank 1/2 gallon of that water per day, then you drank 1.2 mg of lead.

According to the figures, if you eat a 1.55 oz Hersheys Special Dark then you would have only eaten 0.0021 mg of lead.
2.65 * 0.0005 MADL mg * 1.55 oz = 0.00205375
Not that I condone injesting lead but that is far less than what they drink at that Elementary School.

The only reason they are saying "dark chocolate" and not "milk chocolate" is because the addition of milk into the chocolate dilutes the cocoa and lead enough to be below their "safe limit" but it is still in there.

 

[Oliver Buckle]

YumYum, the lead came from dust when drying the beans, not taken up by the plant, that was only the cadmium. My guess is that's lead from petrol engines.
I thought it was interesting that older bushes had beans with much higher levels of cadmium, does it accumulate in the bush do you think? Or maybe a deeper root system reaches a more contaminated source?

 

[YumYum]

In the US fuel doesn't have lead in it anymore. A long time ago it did. It was banned for the fact it was exhausting lead into the atmosphere. I'm not sure about any other countries banning leaded gasoline, but yea it could come through the exhaust pipe and land on beans being dryed by a roadside. Radiators have had lead solder in them which could potentially make it through the exhaust pipe via a bad head gasket or something. I'd hate to know there is lead dust flying around for me to breathe.

Lead is similar to calcium. When humans injest lead, the body doesn't know the difference so it goes into the bones and doesn't move. Mabye that is what happens with the outer shell of the bean, replacing calcium with lead because more calcium is supposed to go into the shell than the rest of the bean?

 

[Oliver Buckle]

I think it was in the second article they talked about the origins of the metals, and the lead definitely turned up after harvest when the beans were drying. We don't have leaded petrol here anymore either, but I had assumed most cacao originated in South America using cheap labour. I don't know what happens there either, but if there are ancient engines, unadapted to unleaded fuel, that would be where I would expect to find them. Also I don't know how long lead would hang about? I bet if you grew crops on the central reservation of a freeway they would still be fairly contaminated, it's not very reactive stuff on the whole.
I am still wondering about the older bushes having higher cadmium levels, larger, deeper root systems is the only explanation I can come up with. The authors suggest mixing beans from young and old bushes and eating chocolate with lower proportions of coca mass. They say eating an ounce of 80% dark chocolate a day would soon lead to real problems, but I thought that it was accumulative, so you would still get problems with less, it would just take a bit longer.

 

[DirtMechanic]

I think it was in the second article they talked about the origins of the metals, and the lead definitely turned up after harvest when the beans were drying. We don't have leaded petrol here anymore either, but I had assumed most cacao originated in South America using cheap labour. I don't know what happens there either, but if there are ancient engines, unadapted to unleaded fuel, that would be where I would expect to find them. Also I don't know how long lead would hang about? I bet if you grew crops on the central reservation of a freeway they would still be fairly contaminated, it's not very reactive stuff on the whole.
I am still wondering about the older bushes having higher cadmium levels, larger, deeper root systems is the only explanation I can come up with. The authors suggest mixing beans from young and old bushes and eating chocolate with lower proportions of coca mass. They say eating an ounce of 80% dark chocolate a day would soon lead to real problems, but I thought that it was accumulative, so you would still get problems with less, it would just take a bit longer.

I read the lead accumulated in the shells such that as they were spread out to dry and have the shells cracked off the residues were exposed to the shelled meat. They are not cleaning the area between dryings from what I understand.

 

[YumYum]

I am still wondering about the older bushes having higher cadmium levels, larger, deeper root systems is the only explanation I can come up with.

I don't know anything about cocoa plants but a picture I saw showed a deep tap root so I think that could be. I imagine South America too when I think of this.

I read the lead accumulated in the shells such that as they were spread out to dry and have the shells cracked off the residues were exposed to the shelled meat. They are not cleaning the area between dryings from what I understand.

That would be a good place to start.

This page from 2005 says Nigeria uses leaded gasoline and contamination from leaded gasoline emissions may occur during the fermentation and sun-drying of unshelled beans at cocoa farms. Imagine what kind of health the workers are in.

 

[cpp gardener]

While Cacao trees are native to Central and South America, the vast majority of beans are produced in Africa. I think mainly because there are fewer pests and diseases that affect them since they aren’t native.
The Cadmium is accumulated from naturally occurring deposits in the soil. That’s why older trees produce higher concentrations than younger trees.