For a while now, levels of heavy metals such as lead and cadmium in cacao and chocolate products reported as high compared to other foods have been among the biggest scares in the high flavanol cacao space. It is an undoubtedly important topic of discussion which has already led to positive change in the industry, with a standard of keeping up-to-date and publicly available test results being practiced in some form by almost every major brand. But with this transparency, the outlier of California’s Prop 65 is bound to come up.
Looking through the published heavy metal results of these same trusted cacao brands, it is not hard to notice that virtually none of them fall below the levels outlined in Prop 65. Some, including Vital Purple, remain transparent about this issue by addressing it directly. This begs the question, however: is cacao truly a safe-to-consume superfood if California considers its natural lead and cadmium levels to be potentially hazardous? Read on to find out why Prop 65 might not be telling the whole story:
Table of contents
Cacao and Heavy Metals: The Basics
We talked about this in our last article covering how cacao’s minerals and nutrients may actually help offset heavy metal absorption in the body, but to briefly touch on it again, cacao containing trace heavy metals such as lead and cadmium is very natural. It absorbs these elements from the soil, especially the highly fertile volcanic soil of the regions of Latin America where it is commonly grown, and does so more than most other plants. The nature of providing minimally-processed (or in Vital Purple’s case, raw) cacao means they cannot be removed as easily as in industrial operations, but every major brand who posts results falls well within the federal guidelines for acceptable levels of those substances in food.
Cacao has been safely cultivated and consumed for thousands of years now in the same regions single-origin brands now source their product from.[1] This is not to say organic and high flavanol cacao brands should be exempt from scrutiny, of course, but rather that cacao’s trace heavy metals are not enough to make it exceedingly dangerous, nor do they negate its other powerful health benefits. Important to note as well is that every batch is different, grown differently in different soil in entirely different areas, meaning no two batches should be expected to test exactly the same on heavy metals either.
Key Takeaways:
Cacao’s trace heavy metals are naturally absorbed from the soil where they are grown
Cacao has been safely consumed in these same regions for thousands of years
No two batches are the exact same, and will test a bit differently on heavy metals
Prop 65: An Overview
Officially the Safe Drinking Water and Toxic Enforcement Act, Prop 65 is a long-standing law targeting products containing chemicals that can cause increased risk of cancer or reproductive harm. Rather than outlawing products that would be available elsewhere in the U.S., however, Prop 65 requires warning labels at levels far lower than what the FDA’s guidelines specify. With the understanding that these governing bodies still do not consider any level of food lead exposure to be strictly “safe”, the discrepancy between federal and state regulations on this issue is still very important to understand.
For instance, the FDA determines that 2.2 and 8.8 micrograms per day are the levels at which lead in food becomes potentially harmful to children and adult women respectively.[2] This includes a 10x safety factor, meaning the federal standard is ten times lower than what would be required for the CDC to recommend clinical monitoring for lead exposure in children. In California, meanwhile, a level above 0.5 micrograms per day could require a Prop 65 warning label.[3] For Cadmium, the FDA’s reference value is 0.21-0.36 micrograms per kilogram of body weight per day, whereas Prop 65’s is 4.1 micrograms per day across the board.
Key Takeaways:
Prop 65 is a California law requiring warning labels on products containing certain chemicals
Prop 65 does not ban products that are available in other states
Prop 65’s limits are much stricter and less context-dependent than those of the FDA
Why Prop 65 Doesn’t Tell the Whole Story: Different Limits for Different Foods
Everyone agrees strict regulation and transparency surrounding potentially harmful substances in food is an unequivocal good. This is precisely why Vital Purple specifies our cacao products do not fall within Prop 65’s warning label threshold even though we are not legally required to. However, the nuance of the FDA guidelines taking into account differences between foods and those at lesser or greater risk likely makes them a much better way to assess the safety of cacao than Prop 65’s across-the-board limits.
As said, one major factor explaining the discrepancy between Prop 65 and federal heavy metal guidelines is the context the FDA allows for between different foods. Everything we eat or drink will likely contain some trace amount of naturally-occurring heavy metals, but whether a food is known to absorb slightly more during growth and if it is typically consumed as part of a balanced diet that can mitigate the risk are important to take into account.
With this in mind, the FDA sets a 5 parts per billion limit in bottled water, a 10 ppb limit on fruits as well as most vegetables and meats used in baby food, and a 20 ppb limit on root vegetables and cereals used in baby food.[4] Prop 65, on the other hand, sets that same 0.5 microgram per day limit regardless of the food product in question.
Key Takeaways:
Prop 65 limits are set across the board regardless of the food in question
Cacao and other foods naturally absorb slightly more heavy metals during growth
The FDA sets limits based on the differing needs of different foods
Why Prop 65 Doesn't Tell the Whole Story: Discrepancy in Calculations
Another set of factors leading to Prop 65’s stricter limits relates to how they calculate them in the first place. Firstly, these calculations assume any potentially harmful chemicals are 100% bioavailable, that is, that 100% of the amount consumed is absorbed by and has an effect on the body.[5] This is another area where food-specific context matters, as if you read our previous article on heavy metals in cacao, you will know that cacao’s mineral and nutrient profile mitigates the absorption of its trace lead and cadmium.
The FDA’s own page on cadmium guidelines corroborates this, suggesting that “even in countries in which the consumption of cocoa products is relatively high”, chocolate and cacao are at best minor sources of cadmium exposure.[6] The statistic they cite says at most under 10%, and as low as 0.1% of cadmium exposure is due to cacao, suggesting not only cacao’s ability to mitigate absorption especially as part of a balanced diet, but that bioavailability of heavy metals is likely not close to 100% anyway.
Also influencing the discrepancy in calculations is the much greater safety factor Prop 65 applies. While the FDA ensures lead limits are ten times lower than the amount the CDC recommends monitoring for, Prop 65 requires warning labels for potential reproductive harm even at a thousand times less than their “no observable effect level”.[7]
All this greatly influences the much stricter limits Prop 65 sets on heavy metals compared to the federal government, and explains why you might see a disclaimer or warning label on organic cacao products. Naturally higher heavy metal content of certain foods, a food’s ability to offset absorption via its nutrients and minerals, and a lower bioavailability of metals in certain foods are not taken into account by Prop 65’s blanket limits.
Key Takeaways:
Prop 65 assumes heavy metals are 100% bioavailable when this is likely far from the case
Cacao’s minerals and nutrients may decrease this absorption rate even further
Prop 65 uses a 1,000x safety factor to get their numbers while the FDA uses a 10x one
Sources:
https://pmc.ncbi.nlm.nih.gov/articles/PMC10920634/ [1]
https://www.fda.gov/food/environmental-contaminants-food/lead-food-and-foodwares [2]
https://pmc.ncbi.nlm.nih.gov/articles/PMC7897270/ [5]
https://www.fda.gov/food/environmental-contaminants-food/cadmium-food-and-foodwares [6]
https://oehha.ca.gov/proposition-65/general-info/proposition-65-plain-language [7]
Why Does Cacao Contain Trace Heavy Metals?
Cacao absorbs trace amounts of heavy metals, such as lead and cadmium, as a natural consequence of absorption from the soil in which they are grown. The highly-fertile, often volcanic soil of Latin America combined with the plant's natural ability to absorb substances well means they do list high among the foods containing these chemicals, but they also contain other nutrients and minerals which greatly help offset their absorption.
Does Prop 65 Mean Cacao Is Unsafe?
In most cases, no. Prop 65's limits for warning labels are quite strict, and are set across the board regardless of differing context between foods. Cacao's natural absorption of trace lead and cadmium as well as its nutrients and minerals help offset absorption of these chemicals is not take into account when setting limits.
Why Are Prop 65's Limits So Strict?
Prop 65 assumes a 100% absorption rate on potentially harmful chemicals and has a much greater safety factor than the FDA. It also does not distinguish between different foods, nor does it have any sort of weight-to-consumption ratio like FDA limits often do.
Phillip McCauley
Phillip McCauley is the owner of Natural Zing and Vital Purple at TheOrganicCacao.com.
Writer / Researcher: Trey Norbey
