Can Steaming Reduce Rice Arsenic Levels? The Surprising Truth

December 8, 2025 •

3 min read

According to the World Health Organization (WHO), rice absorbs significantly more arsenic than other crops, a health concern that has led many to seek safer preparation methods. A common question that arises is: can steaming reduce rice arsenic levels? The answer is more complex than a simple yes or no, as it depends on the exact cooking method and water-to-rice ratio used.

Quick Summary

Steaming is generally less effective at removing arsenic from rice compared to methods that use and discard excess water. Maximum arsenic reduction is achieved through parboiling or boiling in a high volume of water, which leaches the contaminants out before draining.

Key Points

Steaming is Minimally Effective: Because steaming uses an absorption method, most of the leached, water-soluble arsenic is reabsorbed back into the rice.
Boiling is Most Effective: Cooking rice in a large volume of excess water, then discarding it, can remove a substantial amount of arsenic.
The PBA Method is an Excellent Compromise: The parboiling with absorption (PBA) method removes a high percentage of arsenic while preserving the nutritional value and preferred texture of the rice.
Brown Rice Has Higher Arsenic Levels: Due to arsenic accumulation in the outer bran layer, brown rice contains more arsenic than polished white rice.
Water Quality Matters: Using arsenic-contaminated water for cooking can contaminate the rice, even if the grain itself has low initial levels.
Always Rinse and Consider Soaking: Rinsing rice multiple times can help remove surface arsenic, and pre-soaking can further enhance removal, especially when combined with boiling.

Steaming vs. Boiling: Why the Water Ratio Matters

Steaming rice involves using a specific, limited amount of water that is fully absorbed by the grain during cooking. This "absorption method" is convenient but fundamentally limits the removal of water-soluble arsenic. Since the arsenic leached out of the rice ends up in the cooking water, an absorption method traps most of the heavy metal within the final product.

In contrast, boiling rice in a large volume of water and then draining the excess is far more effective. This process, often called the "pasta method," allows the arsenic to leach into the cooking water, which is then discarded. Studies have shown that a high water-to-rice ratio (6:1) can remove a large percentage of inorganic arsenic, the more toxic form.

The “Parboiling with Absorption” (PBA) Method

For those who prefer a fluffier texture than the excess-water method provides, a hybrid technique known as the "parboiling with absorption" (PBA) method is an excellent compromise. This technique was developed to maximize arsenic removal while retaining nutrients.

Here is a step-by-step breakdown of the PBA method:

Initial Rinse and Parboil: First, add rice to pre-boiled water in a ratio of 1:4 (rice to water) and simmer for 5 minutes. This initial boil is crucial for leaching surface-bound arsenic.
Drain and Refresh: After the initial 5-minute parboil, drain the water, which now contains a significant portion of the inorganic arsenic.
Final Cook: Return the rice to the pot, add fresh water (using a lower ratio, like 1:2), and cook on low heat until all the water is absorbed.
Results: Studies have demonstrated that the PBA method removes 54% of inorganic arsenic from brown rice and 73% from white rice, all while retaining essential minerals.

Additional Factors for Minimizing Arsenic in Rice

While cooking methods are key, other factors also play a significant role in determining the final arsenic level in your rice.

Choosing the Right Rice: Brown rice typically contains higher levels of inorganic arsenic than white rice because arsenic accumulates in the bran layer, which is removed during the milling process for white rice. Opting for white rice or certain varieties like basmati, which often have lower baseline levels, can help.
The Source of Your Water: The quality of your cooking water is paramount. If you live in an area with high arsenic contamination in the tap water, cooking with that water can actually increase the arsenic content of your rice. Always use clean, low-arsenic water for cooking and rinsing.
Pre-Soaking: Soaking rice overnight before cooking can further reduce total arsenic content by up to 18% when combined with the excess-water method. This practice promotes the leaching of inorganic arsenic into the soaking water, which should be discarded.

Comparison of Cooking Methods for Arsenic Reduction


Cooking Method	Water-to-Rice Ratio	Arsenic Removal Efficacy	Key Characteristic
Steaming (Absorption)	1:2 to 1:2.5	Minimal to None	All water is absorbed, trapping arsenic.
Boiling (Excess Water)	6:1 or higher	Up to 60% or more	Uses a large volume of water that is drained.
Parboiling & Absorption (PBA)	1:4 (parboil), then 1:2 (absorb)	High (73% white, 54% brown)	Two-step process that discards initial water.
Soaking + Boiling	5:1 (boil) after overnight soak	High (can exceed 80%)	Soaking promotes leaching, boiling drains contaminants.

Conclusion: Steaming is Not the Solution for Arsenic Reduction

Based on scientific findings, relying on steaming alone is not an effective strategy to significantly reduce the arsenic content in rice. Because the limited cooking water is fully absorbed, the arsenic is simply retained within the finished dish. For those concerned about arsenic exposure, particularly in rice-heavy diets or for young children, adopting a method that involves discarding excess water is far more beneficial. The most effective and widely recommended methods involve either boiling with a large excess of water, or the two-step parboiling with absorption (PBA) technique. Combining these strategies with a thorough rinse, using clean water, and choosing rice types with naturally lower arsenic levels offers the best approach to ensuring a safer, healthier meal. For further reading, consult the World Health Organization (WHO) and other food safety authorities on their recommendations regarding heavy metals in food.

Frequently Asked Questions

Steaming is one of the least effective methods for removing arsenic. Unlike boiling in excess water, where arsenic can be drained off, steaming involves the rice absorbing all the cooking water, meaning most of the leached arsenic is reabsorbed.

No, a standard rice cooker that cooks by absorption is not effective at removing arsenic. The process traps the arsenic inside the rice grain along with the water, which is why methods involving discarding excess water are recommended instead.

The most effective method is boiling rice in a high volume of water (at least a 6:1 ratio of water to rice) and then draining the excess water, similar to cooking pasta. This can remove 40-60% of the inorganic arsenic.

Yes, brown rice typically contains higher levels of arsenic than white rice. This is because arsenic accumulates in the outer bran layer of the grain, which is removed during the polishing process for white rice.

Rinsing rice multiple times before cooking can help remove some surface arsenic, though its effectiveness varies by rice type. Combining rinsing with cooking in excess water is a more powerful approach.

While soaking rice before cooking can promote some arsenic leaching, it is not a standalone solution. For best results, soaking should be combined with cooking methods that involve draining the contaminated water.

The PBA method involves a two-step process. Rice is first parboiled briefly in a high volume of water for about 5 minutes to remove a significant amount of arsenic. This water is then discarded, and the rice is cooked with fresh, clean water until absorbed, resulting in both low arsenic and a preferred texture.