Rome - The world simultaneously grapples with the need to produce more food and the need to curb greenhouse gas emissions from the agricultural sector. There are many different technological, or policy options under development and deployment aimed to address these challenges. One of these options involves the use of substances called environmental inhibitors (EIs) that can help mitigate methane emissions from cows and other livestock, and limit the loss of nitrogen from fertilizers used on farms.
The Food and Agriculture Organization of the United Nations (FAO) has produced a report, Environmental Inhibitors in Agrifood Systems - Considerations for Food Safety Risk Assessment, along with a technical brief, to help guide policy makers and all stakeholders in evaluating any possible food safety risks.
The report notes that the potential transfer of EIs residues into the food chain requires careful evaluation and food safety risk assessment to minimize possible negative implications for human health and trade disruptions.
The report focuses on two broad categories: Methanogenesis inhibitors administered to cows and other livestock that lower methane (CH4) emissions from animals, and nitrogen inhibitors applied to soils that aim to reduce nitrogen losses and nitrous oxide (N2O) emissions from crop production.
On 20 January, FAO experts will outline their findings in a webinar and discuss food safety aspects that need to be considered and addressed when using environmental inhibitors in agrifood systems. Those wishing to participate in the webinar, to be held via Zoom at 10:00 CET, can register here.
"Applying a food safety lens is essential when introducing new practices and technologies in agrifood systems said Corinna Hawkes, Director of Agrifood Systems and Food Safety Division (ESF). "By considering food safety at the outset, we can ensure that efforts to reduce environmental impacts are effective, trusted, and well understood."
Currently, the regulatory frameworks for EIs are fragmented, with data requirements and evaluation schemes differing across regions, highlighting the need for a harmonized approach. FAO supports this approach through the scientific advice provided by international expert committees (the Joint FAO/WHO Expert Committee on Food Additives and the Joint FAO/WHO Meeting on Pesticide Residues) that serves as the foundation for the standards of the Codex Alimentarius Commission.
The publication and webinar fall within the FAO Food Safety Foresight Programme that seeks to identify and monitor emerging food safety issues in rapidly evolving agrifood systems.
Key points
Agricultural sources are estimated to account for 58 percent of global CH4 emissions and 52 percent of N2O emissions, according to the Intergovernmental Panel on Climate Change, and FAO projects that, without mitigation, overall greenhouse gas emissions from agrifood systems will grow by more than 30 percent from 2010 through 2050.
Methanogenesis inhibitors have been identified among the strategies to reduce methane emissions from ruminants. They work in several ways; many of them (for example,
3-nitrooxypropanol [3-NOP]) block the key enzyme that catalyzes the final step of CH4 production by microorganisms in the forestomach of ruminant animals. They can be classified as veterinary drugs in some jurisdictions and feed additives in others, leading to different approaches to risk assessment.
Nitrogen, meanwhile, is a crucial nutrient for plant growth and often the most limiting factor in crop productivity. At the same time, when applied as a fertilizer, much of it is lost to the environment through volatilization, leaching, runoff and other processes.
Nitrogen inhibitors (for example, the nitrification inhibitor dicyandiamide [DCD]) are designed to improve nitrogen use efficiency (NUE). As they are generally applied to soils, their potential movement to plant materials consumed by humans or livestock, or direct ingestion by animals in treated soil can be crucial in the possible entry of these compounds into the food chain.
Regardless of how these groups of chemicals may be classified, the minimum data requirements to establish food safety begin with assessing the presence or absence of residues detected in foods, according to FAO.
