Some dried spices contain 'concerning' levels of toxic heavy metals, study finds

• Several brands of dried spices have sold products containing traces of heavy metals.
• Almost one-third of products tested in a recent study had "concerning" combined levels of arsenic, lead, and cadmium.

Dried thyme and oregano were among the most "surprising and worrisome" sources of heavy metals exposure uncovered in a recent investigation from Consumer Reports.

Nearly a third of 126 store-bought spices tested by the team had high enough levels of arsenic, lead, and cadmium combined to pose a health risk for regular consumers, according to the report published Tuesday.

The organization tested spices made by McCormick, Trader Joe's, and Whole Foods, among other popular national and private-label brands.

Thirty-one products had lead levels that exceeded the maximum amount anyone - adult or child - should have in a day, according to Consumer Reports' experts. Frequent exposures to even smaller amounts of lead and other heavy metals can affect brain development in children and overall health in adults.

Thyme and oregano topped the charts for the most widespread contamination; all five thyme products and seven types of ground oregano tested had concerning levels of heavy metals.

Across the rack, there was no single predictor of which spices had the highest metal levels. For some brands, one product would raise moderate concern while others would pass the test, and labels like "organic" and "packed in the USA" didn't matter.

Black pepper, curry, and garlic powder were among the safer spices

Not all of the spices tested positive for heavy metals. Black pepper, coriander, curry powder, garlic powder, saffron, sesame seed and white pepper all passed with "no concern."

Other spices - basil, chili powder, cumin, ginger, paprika and turmeric - had mixed rankings of moderate to no concern across various brands. Only three products reached the "high concern" level: La Flor ground oregano, La Flor ground turmeric, and Happy Belly (Amazon) ground thyme.

Products from McCormick, Spice Islands, Great Value (Walmart), Kirkland Signature (Costco), Trader Joe's, and 365 Whole Foods Market all had products that fell either into the "some concern" or "moderate concern" category.

Insider reached out to the companies named in the report and did not get any immediate responses.

Even small amounts of heavy metals could add up in a dangerously well-spiced dish

Although spices represent a relatively small portion of overall dietary lead exposure, traces of the heavy metals can add up over time if you're one to season your food.

For instance, a dish with just a quarter-teaspoon each of Great Value (Walmart) Chili Powder, Trader Joe's Organic Cumin, and La Flor Oregano per serving would contain enough arsenic, cadmium, and lead to pose a concern, Lisa L. Gill wrote for Consumer Reports.

Childhood lead exposure can lead to difficulties with learning, behavior, hearing, and speech. For adults, chronic heavy metal exposure can contribute to central nervous system problems, reproductive problems, and hypertension, and can damage kidney and immune function.