Is There Arsenic in Potato Skins? Understanding the Risks and Safe Practices

December 17, 2025 •

4 min read

Multiple studies have shown that root vegetables, including potatoes, can accumulate heavy metals like arsenic in their skins from contaminated soil. This raises important questions for consumers concerned with food safety: Is there arsenic in potato skins, and what are the real risks?

Quick Summary

Potato skins can accumulate small amounts of arsenic, primarily from contaminated soil, though levels are generally not a health risk for typical consumption. Peeling can significantly reduce exposure, particularly for potatoes grown in historically polluted areas.

Key Points

Arsenic Accumulation: Arsenic can be found in potato skins, absorbed from the soil where the vegetable is grown.
Low Health Risk for Most: For potatoes from typical, commercially regulated farms, arsenic levels in the skin are generally too low to pose a health risk.
Peeling is a Precaution: Peeling potatoes is the most effective way to remove accumulated arsenic and is highly recommended if the potatoes were grown in potentially contaminated soil.
Arsenic vs. Solanine: Do not confuse arsenic with solanine, the neurotoxin indicated by greening and sprouting. Store potatoes properly to prevent solanine formation.
Wash Thoroughly: Always scrub potatoes well with a brush to remove surface soil, which may contain heavy metal residue.
Contaminated Soil: Potatoes grown in areas with historically high arsenic levels, such as old orchard lands, pose a higher risk.
Nutritional Value: Potato skins contain valuable fiber, vitamins, and minerals, but a safe preparation method is important.

The Science Behind Arsenic Accumulation in Potatoes

Arsenic is a naturally occurring element found in the earth's crust, but it can also enter soil and water through human activities, such as industrial pollution and the historical use of lead arsenate pesticides. As a root vegetable, the potato grows in direct contact with the soil, and like other plants, it absorbs water and nutrients from its environment. During this process, any heavy metals present in the soil can be taken up by the plant. Research confirms that heavy metals, including arsenic, are preferentially accumulated in the outer layers and skin of root vegetables like potatoes and carrots. A study by the USDA found that arsenic concentration was, on average, 61% higher in the peel than in the peeled tuber when grown in historically contaminated orchard soils. This confirms that while the entire potato may contain trace amounts of arsenic, the skin is where it is most concentrated.

Arsenic vs. Solanine: A Critical Distinction

It is crucial to differentiate between arsenic, a heavy metal absorbed from the soil, and solanine, a natural toxin produced by the potato plant itself. Solanine is a glycoalkaloid that acts as a natural pesticide, and its levels increase when potatoes are exposed to light, causing them to turn green. This greening is a visual indicator of potentially high solanine levels, which can cause digestive issues, headaches, or more severe neurological problems if consumed in large quantities. Unlike arsenic, which is removed primarily by peeling, solanine is not effectively destroyed by cooking methods like boiling or baking. To protect against solanine poisoning, any green parts or sprouts should be completely removed and discarded. Arsenic, on the other hand, is an environmental contaminant, and while its accumulation is a concern, it is a separate issue from solanine.

Factors Influencing Arsenic Levels in Potatoes

The amount of arsenic in a potato's skin depends on several factors, with the most significant being the level of contamination in the soil where it was grown.

Soil Quality: The primary determinant is the arsenic concentration in the soil itself. Potatoes grown in areas with naturally high arsenic levels or on land historically treated with lead arsenate pesticides will have higher uptake.
Growing Location: Local soil composition and history play a major role. For example, some areas have stricter regulations or less historical contamination than others.
Bioavailability: Soil properties like pH can affect how readily plants absorb heavy metals. Some studies have shown that lower soil pH can increase the bioavailability of certain metals, though this effect can vary.

Commercial vs. Home-Grown Potatoes

For most consumers purchasing potatoes from a typical grocery store, the risk from arsenic in potato skins is very low. Commercial farms operate under regulations and are typically not located on heavily contaminated land. However, those who grow their own potatoes on land with unknown history, such as former agricultural fields, or live in areas with known contamination should take extra precautions. A specific study on potatoes grown in a contaminated soil region found that while soil arsenic levels were elevated, the arsenic in the edible potato flesh was below detection limits, indicating low transfer efficiency.

Comparison of Potato Skin and Flesh

To make an informed decision, it is helpful to weigh the benefits and risks of consuming potato skins.


Feature	Potato Skin	Potato Flesh
Heavy Metal Concentration	Higher concentration, especially of arsenic, lead, and cadmium, absorbed from soil.	Significantly lower heavy metal concentration, even in contaminated environments.
Fiber Content	Rich in fiber, which supports digestion and gut health.	Contains a moderate amount of soluble fiber, but less than the skin.
Vitamins	Contains vitamin C, but less than the flesh.	Primary source of vitamin C in the potato.
Minerals	Contains significant amounts of iron, potassium, and magnesium.	Also contains potassium and magnesium, but a large portion is in the flesh.
Antioxidants	Rich in antioxidants, such as polyphenols and flavonoids.	Contains fewer antioxidants than the skin.
Natural Toxins	Can contain solanine if green or sprouted.	Can contain solanine, especially if the green coloring has spread into the flesh.

Practical Steps for Reducing Arsenic and Other Toxins

Wash Thoroughly: Always scrub potatoes well under running water using a vegetable brush to remove any lingering soil particles.
Peel When in Doubt: If you are uncertain about the soil conditions where your potatoes were grown, peeling them is the most effective method for removing potential heavy metal contamination.
Inspect for Greening: Store potatoes in a cool, dark, and dry place. If the skin has turned green or started to sprout, cut away and discard those sections entirely, as they contain higher levels of solanine.
Vary Your Diet: Diversifying your vegetable intake reduces the risk of over-consuming any single potential contaminant source.
Consider Origin: If you have concerns about local soil contamination, consider purchasing produce from certified organic growers or suppliers who test their products for heavy metals.

Conclusion: The Final Verdict on Potato Skins

While it is true that trace amounts of arsenic can accumulate in potato skins, especially when grown in contaminated soil, the risk for the average consumer is minimal. For commercially sourced potatoes, the levels are generally not a cause for concern. The potential health benefits of consuming the skin, which is rich in fiber, vitamins, and minerals, can outweigh the very small risks for most people. The key lies in informed preparation. By properly washing your potatoes and peeling them when there is a risk of contamination (such as from unknown or historically polluted land), you can enjoy the nutritional benefits of the entire vegetable while safely minimizing your exposure to potential heavy metals. Always be vigilant for signs of solanine, like green spots, and remove them completely before cooking.

Learn more about food contaminants from the World Health Organization.

Frequently Asked Questions

Yes, it is generally safe to eat potato skins from commercially sourced potatoes. The skin is a nutritious source of fiber, vitamins, and minerals. However, if you are unsure of the potato's origin or suspect soil contamination, peeling is the safest option.

Arsenic is absorbed by the potato from the soil it grows in, and it tends to accumulate most heavily in the outer layers, or skin. The source of the arsenic can be natural geology or man-made contamination, such as from historical pesticide use on farmlands.

You cannot visually detect arsenic in a potato. The risk is primarily based on the soil conditions. If you grow your own potatoes on land with a history of pesticide use (like old orchards), it is best to peel them. For store-bought potatoes, the risk is typically low.

Washing can remove arsenic that is on the surface in residual soil, but it will not remove the arsenic that has been absorbed into the skin tissue itself. Peeling is the most effective way to eliminate the majority of the arsenic absorbed by the skin.

Green potatoes or those with sprouts should not be consumed, even after peeling. The green color indicates the presence of solanine, a natural neurotoxin. You should trim away any green areas or sprouts completely, but if the potato is very green or bitter, it is best to discard it.

Yes, research shows that other heavy metals such as cadmium and lead can also accumulate in potato skins, with higher concentrations in the peel than the flesh. Like arsenic, this accumulation is dependent on the soil quality.

For most people eating commercially grown potatoes, the nutritional benefits of the skin (fiber, minerals, vitamins) far outweigh the minimal risk from trace arsenic. The key is proper preparation, including thorough washing and peeling if contamination is suspected.