Agronomic solutions to decrease arsenic concentrations in rice

Area of Science:

• Environmental Science
• Agricultural Science
• Food Science

Background:

• Rice plants readily accumulate arsenic (As), a toxic metalloid present naturally and from pollution in agricultural soils.
• Elevated As concentrations in rice grains pose significant human health risks, especially with regular consumption and use in infant foods.

Purpose of the Study:

• To review evidence-based strategies for mitigating arsenic accumulation in rice.
• To provide recommendations for implementing these arsenic reduction techniques.
• To identify barriers and knowledge gaps from producer and stakeholder perspectives.

Main Methods:

• Comprehensive literature review of arsenic mitigation strategies in rice.
• Interviews with rice producers and stakeholders to assess implementation challenges.
• Analysis of irrigation management, soil/foliar amendments, cultivar selection, and post-harvest processing.

Main Results:

• Alternate wetting and drying (AWD) irrigation is a highly effective, climate-smart, and potentially cost-neutral method to reduce grain As.
• Combining AWD irrigation with specific soil amendments significantly enhanced arsenic reduction.
• Most field-level mitigation strategies lack large-scale, commercial production trial data.

Conclusions:

• Integrated approaches, combining irrigation and amendments, offer the most effective arsenic reduction in rice.
• Developing and implementing best management strategies requires farmer collaboration and further large-scale field research.
• Addressing knowledge gaps and farm-specific circumstances is essential for widespread adoption of mitigation techniques.