Does Coffee Have Heavy Metals?

Coffee, like many agricultural foods, may contain trace amounts of heavy metals (Pb, Cd, As, Hg). Whether these levels present a concern depends on their concentration, the amount consumed and total dietary exposure. 

To answer the question “Does coffee have heavy metals in dangerous amounts?”, first assess the producer and their sourcing. Proper quality control helps ensure those amounts are within appropriate quality and safety expectations.

Are There Heavy Metals in Coffee?

The answer to “are there heavy metals in coffee?” is yes, it can naturally contain lead, cadmium, arsenic and mercury because it grows in soil and passes through several production stages. However, they are present in very small amounts that do not necessarily make the drink unsafe. 

At a glance

A peer-reviewed survey of eight roasted Arabica samples reported the ranges below. 1 ppm (parts per million) = 1mg/kg of total mass. 1 µg = 0.000000001 kg.

These benchmarks reflect total daily exposure to heavy metals through diet and environment..

How Do Heavy Metals Get Into Coffee?

Heavy metals in coffee accumulate during growth and processing.

Natural Soil Uptake

Minerals that are already in the soil are absorbed by coffee roots. Heavy metal levels in beans can vary depending on whether the soil is mineral-rich or volcanic.

Fertilizers, Irrigation & Environmental Contamination

Cadmium can be introduced by some phosphate fertilizers. If the field is exposed to industrial runoff or contaminated irrigation, additional heavy metals may also be injected.

Processing, Drying & Roasting

Water, dust, or equipment can increase the concentration of heavy metals in coffee during the drying, storing, roasting, and grinding processes. Increased production quality control reduces this impact.

Which Heavy Metals Are Found in Coffee 

The main heavy metal contaminants in coffee are lead, cadmium, arsenic and mercury.

Lead (Pb)

Lead is a cumulative neurotoxicant that can also affect the cardiovascular system and kidneys. May enter coffee through soil, airborne pollution or processing contact. Lead is regulated by the WHO and FDA, both of which state that there is no safe dose.

Cadmium (Cd)

Cadmium accumulates mainly in the kidneys and may cause renal health problems. Common sources include soil deposits and phosphate fertilizers. Is regulated by the FDA, with a weekly intake benchmark of 0.21-0.34 µg/kg bw.

Arsenic (As)

Chronic exposure to inorganic arsenic has been linked to skin lesions and increased cancer risk. Enters crops mostly via contaminated soil and irrigation water. No tolerable intake level has been established for inorganic arsenic, but EFSA cites 0.06 μg/kg bw per day as the lowest dose associated with skin problems.

Mercury (Hg)

Mercury can affect the nervous, digestive and immune systems. It mostly contaminates crops through the water and soil. Mercury is regulated by most of the world’s health organizations, with the Govt of Canada citing 0.47 µg/kg bw as the tolerable daily intake.

How Do Coffee Brands Test for Heavy Metals?

Many quality-focused brands use independent testing to verify if their coffee is high in heavy metals. They normally do it in accredited labs, using sensitive methods like ICP-MS, which can detect very low concentrations. Quality control should also include supplier approval, certificates of analysis, ingredient traceability, and batch-specific testing prior to product release. The results must then be compared with the relevant limits for each sales market, as requirements vary by contaminant and product category.

The current MDLA Wellness Organic Mushroom Coffee production batch was independently tested by Eurofins for selected heavy metals, mycotoxins and microbiological parameters. We also work with certified suppliers and document our standards on the Product Quality and Ingredients & Quality pages. Some more strong transparency signals include disclosing the laboratory, testing scope and product batch where available.

Should You Be Worried? What "Safe Exposure" Actually Means

The concern with toxic heavy metals is cumulative intake, since some can remain in the body and add to exposure from water and other foods. However, published coffee assessments have generally reported hazard quotients below levels of concern for the samples and consumption patterns studied. In those studies, exposure to heavy metals from coffee was not considered significant.

That does not make every origin or batch identical; risk still depends on concentration, serving size, frequency and the rest of your diet. Coffee's established health benefits also remain relevant, so the sensible response is quality control rather than stopping drinking coffee altogether. Instead, look for reputable providers who are transparent about their sourcing and testing.

How to Choose a Coffee Brand That's Tested for Heavy Metals

• Look for an independent laboratory. Check for a named lab and a stated testing scope.

• Check the finished product. Confirm which exact item was analyzed rather than relying on a generic ingredient report.

• Review the testing panel. It should test heavy metals such as lead, cadmium, arsenic, mercury, with mycotoxins and other relevant contaminants, depending on the product and sourcing risk.

• Confirm sourcing controls. Check for supplier standards and manufacturing information.

• Do not treat organic as a lab result. Certification cannot guarantee the lowest levels of naturally occurring metals. Look for both certification and independent analysis.

To choose a high-quality functional drink, explore our Organic Mushroom Coffee with Lion's Mane and Chaga, with the current batch being independently tested for heavy metals, mycotoxins and microbiological parameters by Eurofins.

See how MDLA Wellness approaches sourcing, testing and transparent quality, then choose the blend that fits your routine.

FAQ

Does all coffee have heavy metals?

No, metals may be detected in some samples and remain below laboratory detection limits in others. The amount depends on coffee’s growing conditions and post-harvest handling. 

Is coffee high in heavy metals compared to tea or cocoa?

No, coffee isn’t classified as a consistently high-exposure food. In tea and cocoa, heavy metal content also varies widely by origin and preparation.

Are heavy metals in coffee dangerous during pregnancy?

Heavy-metal exposure is an important consideration during pregnancy, particularly for lead and mercury. However, the extent of exposure to them from coffee depends on the measured concentration and the amount consumed. Pregnant consumers should also follow medical guidance regarding caffeine intake and discuss individual concerns with their healthcare professional.

Does organic coffee have fewer heavy metals?

Organic coffee can reduce synthetic inputs, but metals may naturally occur in water or soil. The best criteria for clean coffee are independent testing and rigorous quality control.

How can I tell if my coffee has been tested?

Look for a named laboratory, a dated certificate and a list of analytes.

Does brewing coffee remove heavy metals?

Brewing changes how much transfers into the drink and research shows that some metals (lead, cadmium included), can pass into the infusion. Water quality and brewing method also affect the final coffee heavy metal concentrations.

Explore MDLA Wellness organic coffee. Rigorous quality control, transparent testing, high-grade ingredients.

Sources

1. EFSA, “PLS: Update of the risk assessment of inorganic arsenic in food”, 18 January, 2024 https://www.efsa.europa.eu/en/plain-language-summary/update-risk-assessment-inorganic-arsenic-food

2. FDA, “Lead in Food and Foodwares”, 6 January, 2025 https://www.fda.gov/food/environmental-contaminants-food/lead-food-and-foodwares

3. FDA, “Cadmium in Food and Foodwares” https://www.fda.gov/food/environmental-contaminants-food/cadmium-food-and-foodwares

4. Kowalska, G., “The Safety Assessment of Toxic Metals in Commonly Used Herbs, Spices, Tea and Coffee in Poland”, International Journal of Environmental Research and Public Health, 2021
   https://www.mdpi.com/1660-4601/18/11/5779

5. MDLA Wellness, Product Quality
   https://mdlawellness.com/pages/product-quality

6. MDLA Wellness, Ingredients & Quality
   https://mdlawellness.com/pages/ingredients-quality

7. MDLA Wellness, Organic Mushroom Coffee with Lion’s Mane & Chaga https://mdlawellness.com/products/organic-mushroom-coffee-fusion-lion-s-mane-chaga

8. WHO, “Mercury”, 24 October, 2024
   https://www.who.int/news-room/fact-sheets/detail/mercury-and-health

9. WHO, “Lead poisoning”, 10 June, 2026
   https://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health

10. Winiarska-Mieczan, A., Kwiatkowska, K., Kwiecień, M., Zaricka, E., “Assessment of the risk of exposure to cadmium and lead as a result of the consumption of coffee infusions”, Biological Trace Element Research, 2020
    https://pmc.ncbi.nlm.nih.gov/articles/PMC8055627/

11. Health Canada, “Mercury in Fish: Questions and Answers” https://www.canada.ca/en/health-canada/services/food-nutrition/food-safety/chemical-contaminants/environmental-contaminants/mercury/mercury-fish-questions-answers.html