Prop 65 warning (California)

WARNING: This product contains lead, a chemical known to the State of California to cause birth defects and other reproductive harm.

It is one of the requirements for current Good Manufacturing Practices (cGMP) if we are to sell this product in California according to the so called "Proposition 65".

Customers from California do not react to this warning since it is on most supplements (especially if containing vitamins from fruit/vegetables), but we do not remove this warning when shipping to other states (even though we could of course - but that would mean unnecessary costs). If you were to take many different supplements containing all the nutrients in our supplement, you would get at least the same lead content even if there is no warning (because current Good Manufacturing Practices does not require this on the label if sold outside of California, and sometimes a low-dose or one-ingredient supplement does not contain that much in each tablet).

The lead content is minimal. It is only occurring naturally in some ingredients. The warning is only something we have on the label due to California Law. If we did not sell this to California, we would not need to put the warning there. The prop 65 limit for pregnant women (not cancer) is extremely stringent.

The State of California has established a limit for the lead level in foods much lower than the federal limit set by the U.S. Food and Drug Administration (FDA). For example, the federal limit for pregnant women is 25 micrograms per day, which is 50 times more than the limit in California (0.5 micrograms per day). The result is that some products containing powdered fruits and vegetables may meet the federal limit, but exceed the stricter California limit. In this case, California requires an additional warning.

Often, Larger companies that sell supplements have one label for California and another label for other states (for instance Thorne), and there is similar information on these websites:

“For example, for lead, for children under the age of six, the U.S. Food and Drug Administration has established the “provisional total tolerable intake level” at six micrograms of lead per day.  Consuming less than this amount of lead daily is an amount the U.S. Food and Drug Administration deems to be safe for children in this age group.  By contrast, Proposition 65 requires a warning notice on any product that provides 0.5 micrograms of lead daily – an amount 12 times lower than the U.S. Food and Drug Administration’s “provisional total tolerable intake level” for daily lead consumption in a six-year-old.  For pregnant women, the U.S. Food and Drug Administration’s “provisional total tolerable intake level” for lead is 25 micrograms daily, which is 50 times greater than the amount requiring a Proposition 65 warning notice.  Finally, the U.S. Food and Drug Administration’s “provisional total tolerable intake level” for nonpregnant adults is set at 75 micrograms of lead daily, which is 150 times greater than the amount requiring a Proposition 65 warning notice in the State of California."

We have only one label (for all states), so people from other states often react to this of course (we have customers in California, but they do not react since that warning is on “everything”):

 Practically all foods contain certain levels of one or more of the substances listed by the State of California. In many cases, the exposure levels established by Prop 65 are less than what occurs naturally in fruits, vegetables, grains, and even drinking water.

Proteins, plants, and minerals all are well-known to contain substances that exceed those allowed exposures on the Prop 65 list.

Prop 65 makes no distinction between natural and artificial products.

Prop 65 requires warning labels to be applied to products which contain chemicals on the list (sold in California).

Lead is one element that is on the list.

Lead is an element that exists in nature. It can be found in varying degrees across the globe. Lead is widely distributed in the environment.

Prop 65 has inadvertently affected dietary supplements and herbal ingredients which naturally contain very low levels of certain elements commonly found in soil, plants, and water – a typical example is lead.

The Prop 65 limit of 0.5 mcg/day for lead is far below the amount of lead naturally found in many fruits, vegetables, and herbs grown on clean, non-contaminated soils.

Various countries and safety organizations have reviewed known studies and science to produce safety guidelines on the levels of heavy metals that can be consumed on a daily basis without causing harm. The Prop 65 levels are among the most stringent and build in a 1000-fold safety factor below the no observable effect level for chemicals listed as “reproductive toxicants” – such as lead.

The lead in herb products is not more or less risky than lead found in the American diet, which is reported to provide about 15–25 mcg of lead per day or more – the lead comes mainly from plant foods.

The State of California requires a warning for any product sold in California that would result in a consumer ingesting more than 0.5 mcg of lead in a day. This is an exceedingly low level that is, by law, 1000 times lower than the highest level of lead known by California NOT to cause reproductive harm. In other words, the Prop 65 warning threshold for lead incorporates a 1000-fold safety factor below the level found to have NO observable effect on humans or animals. Therefore Prop 65 sets an extremely stringent warning threshold.

For comparison, where Prop 65 allows for 0.5 mcg/day of lead the following limits are:

  • 250 mcg/day European Union / FAO / WHO
  • 75 mcg/day US FDA
  • 20 mcg/day AHPA – Canada’s Natural Health Directorate

To put this into perspective:

  • One tablet may typically contain 0.2 mcg of lead
  • A daily dosage of 3 tablets may typically contain 0.6 mcg of lead

All of the ingredients in supplements test well below the international and federal accepted safety standards for lead in dietary supplements.

So, the Prop 65 standard is set far below the lead levels allowed anywhere else and is not based on scientific analysis of actual risks, but on a regulatory system contained within the Proposition.

The warning labels required by Prop 65 do not present information about the safety or the risk of any product.

It is important to note that Prop 65 does not ban any products; it just requires warnings on products that contain certain chemicals."

Required labels are misleading rather than informative.

If you would like to read more about Prop 65, please see the link below:

Other examples:



FDA Drinking water action level (AL) is also higher: 0.015 mg/L (15µg/L). So if you drink 1 liter of water just below the action limit, you would get 25 times more lead than from 3 tablets (or 75 times more than from one tablet)! An AL exceedance is not a violation but can trigger other requirements that include water quality parameter (WQP) monitoring, corrosion control treatment (CCT), source water monitoring/treatment, public education, and lead service line replacement (LSLR).

Why is lead in food and supplement products?

Lead is present in small amounts throughout the environment due to its natural occurrence and as a result of human activities. Plants, including those we eat, can absorb lead from the environment. It is not possible to completely remove these during processing. Thus, many food products, even certified organic fruits and vegetables, would be expected to contain trace amounts of lead. Many common foods meet the federal limit for lead, but exceed the stricter California limit (see Table 1).

Table 1. Common Foods With Lead Levels Above California Proposition 65 Limit


Servings Per Day

Amount of Lead

% Prop 65

Grape juice (diluted from frozen concentrate)

1 cup



Dill cucumber pickles

1 large



Cranberry juice cocktail (canned or bottled)

1 cup



Sweet potatoes (canned)

1/2 cup, mashed



Spinach (fresh/frozen, boiled)

1 cup



Carrots (fresh, boiled)

1/2 cup, slices




1 small box (1.5 oz.)




Source: The Total Diet Study, also known as the Market Basket Study, an ongoing program of the U.S. Food and Drug Administration that determines levels of various nutrients and contaminants in foods. These are representative samples from most recent food analysis (2006 to 2008).