Heavy Metals Testing

To our Seven Sundays family,

Recently many of you have reached out concerning lead in cassava due to Consumer Reports articles. As always, hearing from you makes us a better company, and we appreciate you reaching out. As founders of a cereal brand focused on People & Planet Health, and as parents of children who eat a lot of our cereal, we understand where you are coming from and care deeply about your concern. Our hope is that the information below will make you feel more comfortable, as it did us. 

We pride ourselves on making cereals with 100% real food ingredients that come from a farm, and the reality is that these ingredients often contain trace naturally-occuring metals from the soil. Knowing this, we regularly test our cereals for heavy metals (lead, cadmium, mercury and arsenic) and compare them to all the state, federal and global food safety reference levels to ensure they are safe to consume. The latest results of that analysis are summarized below. 


First, a little background on heavy metals (arsenic, cadmium, copper, iron, lead, mercury, zinc) and how they make their way into our food system. Not all of these metals are bad for you. We need small amounts of some of them, such as zinc and iron, to keep our bodies healthy.  Studies have shown that healthy zinc and iron levels in the body are important in reducing cadmium and lead absorption and can prevent or reduce any adverse effects from other heavy metals.

It is impossible to live in an environment free of heavy metals: they’re in the ground, the water, the air, and in the products we use every day. We have come a long way to limiting exposure in the U.S. over the last few decades and true heavy metal poisoning is rare.  

In 2022, the FDA released a Total Diet Study, which tested levels of heavy metals in 305 foods - mostly unprocessed. In over 3,000 total samples collected, cadmium was the most common metal detected, showing up in 61% of foods ranging from non-detect to 400 parts per billion (ppb). Lead was detected in 15% of foods ranging from non-detect to 164 ppb. 

Trace levels of heavy metals found in our cereals are naturally occurring in the soil. Nothing in our recipe or manufacturing process adds heavy metals. Just as the roots draw up good nutrients into the seed, leaf, bean, or grain, it also draws up these heavy metals. Certain plants (root vegetables, leafy greens, grains, and seeds) are more prone to heavy metals than others. We have found that sunflower seeds, cassava and cocoa are the highest contributors to cadmium and lead in our cereal.


Trace levels of lead are detected in our Sunflower and Oat Protein cereals below the most conservative levels for lead in food set forth in a California State regulation known as “California Proposition 65” (CA Prop 65). Although there is currently no Federal level for lead in food, the levels are also significantly below the recently proposed Food and Drug Administration (FDA) Interim Reference Levels (IRLs), and levels established by other governing bodies like Environmental Protection Agency (EPA) and European Union (EU) for lead in food products. 

The graph below compares the level of lead from our latest laboratory test data to Prop 65 warning levels (often referenced in the Consumer Reports articles), as well as the recently proposed FDA IRLs for children under 2 (adult levels are 4x higher).


Trace levels of naturally-occurring cadmium were also detected in our Sunflower Cereals and Oat Protein Cereals. Our Oat Protein Cereal tested well below any action levels. The levels per serving of cadmium in our Sunflower Cereal can fluctuate, especially during drought years, to levels recently exceeding the CA Prop 65 warning label requirement. As such, we have recently added a label to our Sunflower Cereal to inform California residents. 

When considering a Prop-65 label on a packaged food, it's important to remember that Prop 65 is a right-to-know law, not a safety law. Prop 65 warnings are required for chemical amounts that occur below any levels of concern for the FDA, EPA, and the World Health Organization (WHO). For cadmium, the level that requires the warning about possible reproductive harm or birth defects is 1,000x lower than the level that has been shown in rigorous studies to cause no observable harm.  

The graph below compares the level of cadmium from our latest lab results to the Prop 65 warning levels for cadmium, as well as the EPA Reference dose (Rfd) for cadmium, which is an estimate of a daily exposure to the general population (including sensitive subgroups) that is likely to be without appreciable risk of deleterious effects during a lifetime. The WHO tolerable weekly intake level is a similar interpretation as the EPA, so we group these together for simplicity.

Other Heavy Metals

Arsenic and mercury have not been detected or are at levels that are orders of magnitude below the most stringent State or Federal labeling or reference guidelines.

Next Steps

While we firmly believe our cereals are, and always have been, safe to eat, we will continue to test, inform and reduce the levels of heavy metals in our cereals. We are already working to shift away from ingredients that can be a source of heavy metals (e.g. cassava flour). We are also testing ingredients further up the supply chain to the soil level and expanding our grower network to different regions.  

For additional transparency, we will continue to update this page quarterly with the most recent testing data. This is a complex topic and sometimes it is helpful to talk to a real person. We are here to listen. Please do not hesitate to reach out to us with additional questions or concerns using the form below or by sending an email to realpeople@sevensundays.com.