Written by
Louise W Lu, PhD, MPH, BMLS
Reviewed by
Alexandra V Goldberg, Registered Dietitian
When you think of climate change, you probably imagine melting glaciers, rising sea levels, or extreme weather. But what if we told you that it’s also affecting the safety of your food — especially rice, the daily staple for over half the world’s population?
A groundbreaking new study from Columbia University’s Mailman School of Public Health has uncovered a troubling connection: as the planet warms and carbon dioxide (CO₂) levels rise, arsenic levels in rice are also increasing — and that could raise serious health risks for millions, particularly across Asia (Ziska et al., 2024).
Let’s break down what this means, and what you can do about it.
Jump to a Section:
- Climate Change and Rice: What’s the Link?
- Why Arsenic Is So Dangerous
- How to Reduce Arsenic in Rice at Home
- References
Climate Change and Rice: What’s the Link?
Over the next 25 years, climate models predict many parts of Asia will see average temperature increases of more than 2°C, along with rising levels of carbon dioxide (CO₂).
Researchers from Columbia University, Johns Hopkins, and the Chinese Academy of Sciences found that these changes increase inorganic arsenic (iAs) — the most toxic form — in rice plants.
- Warmer temperatures and CO₂ change soil chemistry in flooded paddy fields.
- This makes arsenic more bioavailable, so rice absorbs it more easily.
- Rice already absorbs more arsenic than other grains due to its waterlogged growth conditions.
Using the FACE (Free-Air CO₂ Enrichment) method, scientists studied 28 rice types over 10 years and modeled the health risks in 7 countries: Bangladesh, China, India, Indonesia, Myanmar, the Philippines, and Vietnam.
- China could face up to 13.4 million new cancer cases by 2050 due to arsenic in rice.
- Other countries may also see increases in lung and bladder cancers, diabetes, and heart disease.
Why Arsenic Is So Dangerous
Arsenic is a naturally occurring toxin found in soil and water. In rice, it builds up in the grain — and in your body.
Long-term arsenic exposure from rice can raise the risk of:
- Lung, bladder, and skin cancer
- Ischemic heart disease
- Type 2 diabetes
- Pregnancy complications
- Developmental problems in children
- Weakened immunity (Ziska et al., 2024)
In parts of southern China, Southeast Asia, and South Asia, rice is already one of the biggest sources of arsenic in the diet.
How to Reduce Arsenic in Rice at Home
Here are simple ways to lower arsenic in rice while preserving nutrients:
Best Method: Parboil + Absorption (Most Effective)
Removes up to 74% of arsenic from white rice and keeps most nutrients intact.
- Rinse rice thoroughly with filtered water.
- Boil enough water (2 cups for every 1 cup of rice).
- Add rice, boil for 5 minutes.
- Drain all water.
- Add fresh filtered water (2:1 ratio) and return to boil.
- Simmer on low until all water is absorbed.
Other Helpful Tips
- Rinse rice 3–5 times before cooking.
- Use extra water (6–10 parts water to 1 part rice) and drain after cooking. Removes 40–60% of arsenic.
- Use filtered water for rinsing and boiling.
References
Ziska, L.H., Wang, D., Kim, B.F., Nachman, K.E., Chiger, A.A., et al. (2024). Impact of climate change on arsenic concentrations in paddy rice and the associated dietary health risks in Asia: an experimental and modelling study. The Lancet Planetary Health.
