Clean Label Project flags alarming levels of contaminants in popular snack and nutrition bars

A new report issued by the Clean Label Project warns of critical levels of contaminants — ranging from heavy metals and pesticides to industrial chemicals like BPA and phthalates — among the most popular snack and nutrition bars on the market. 

Testing 165 top-selling bars from 50 leading brands, the Snack and Nutrition Bar Category Insights Report offers a comprehensive look at what athletes, fitness enthusiasts, and those seeking convenient and healthy on-the-go snacking options are really eating — and what’s left off the label.

Among the most concerning findings, 100% of products tested had detectable levels of heavy metals, with 22% exceeding the US state of California’s Prop 65 limits for lead and 6% for cadmium.

Certified-organic bars, on average, had 28% more heavy metals, and 6% of organic-certified bars (three of 51 organic bars tested) tested high in pesticides banned from organic products.

Products marketed as “gluten-free,” “non-GMO,” “vegan,” “soy-free,” and “dairy-free,” on average, consistently tested higher in heavy metals.

Meanwhile, 97% of products were above the previous Prop 65 limits for acrylamide, a chemical linked to cancer. In May 2025, there was a federal landmark court decision to block cancer warnings for acrylamide under California Prop 65.

In a positive finding, bars labeled “kids,” on average, had significantly lower levels of heavy metals, pesticides, and phthalates than their adult counterparts.

“This study highlights a growing truth: our current food safety regulations simply don’t go far enough to protect all consumers from the hidden risks of today’s industrial food system,” says Jaclyn Bowen, executive director of Clean Label Project.

“We’re seeing widespread contamination — from heavy metals and pesticide residues to chemicals migrating from packaging — yet much of it remains unregulated or overlooked. While overdue reforms are finally starting to protect our most vulnerable populations, like infants and children, it’s high time we acknowledge the broader, pervasive contamination issue.”

Deep dive into food safety

The report is based on over 20,000 laboratory tests conducted in partnership with Ellipse Analytics, an ISO-accredited analytical chemistry lab. Contaminants tested include arsenic, cadmium, lead, mercury, BPA/BPS, phthalates, acrylamide, and over 400 pesticides.

Despite the lack of federal regulation on many of these contaminants, states like California and Maryland are beginning to advance food safety laws, starting with baby food. Clean Label Project aims to expand that conversation to the broader food market, particularly products marketed as “nutritious” or wellness-oriented.

“Snack and nutrition bars are a US$7.4 billion category in the US, consumed daily by people aiming to eat healthier,” underscores Bowen. “But health isn’t just calories or macros — it’s also about contamination.”

“We’re urging brands, retailers, and regulators to make this new frontier of food safety a core part of product development. Nutritious foods start with clean ingredients, which come from healthy soil and water, made possible by strong environmental and food safety policy.”

“A healthier future depends on more than labels — it requires transforming the system behind them.”

The report was published on the heels of a nationwide Healthy Babies Bright Futures study on the levels of heavy metals in best-selling store-bought rice.

Previously, the Clean Label Project published findings that 47% of tested protein powders exceeded at least one federal or state regulatory threshold for heavy metal contamination, such as lead and cadmium. In January, US industry associations, including the Natural Products Association and the Council for Responsible Nutrition, called the report’s methodology and outcomes into question.