Produce Program, VT Agency of Agriculture, Food and Markets
It’s that time of year again – the leaves are changing, the air is crisp, and wait … what’s that smell? It could very well be manure or compost being incorporated into a nearby field. Around this time of year, produce farms across the state add compost, manure, and other amendments to the soil to provide nutrients and organic matter. Manure and compost can be valuable assets to many farms to keep soils healthy. Farms use a variety of methods to incorporate these amendments as well as different techniques for storing, applying, and composting. While soil amendments are important for maintaining on-farm fertility, it’s important to keep in mind potential produce safety risks when handling and applying amendments.
The FSMA Produce Safety Rule
The Food Safety Modernization Act (FSMA) Produce Safety Rule (PSR) is a U.S. Food and Drug Administration regulation that establishes minimum food safety standards for farms that grow, harvest, pack or hold produce in an effort to reduce foodborne illness. The PSR is divided into several sections, called subparts, and includes Subpart F – Biological Soil Amendments of Animal Origin and Human Waste. This subpart contains requirements for soil amendment storage and handling practices, application methods, treatment processes, and recordkeeping. While not every produce farm is subject to the PSR, it’s important to understand the risks associated with soil amendments of animal origin.
The FDA defines biological soil amendment of animal origin (BSAAO) as “a biological soil amendment which consists, in whole or part, of materials of animal origin, such as manure, or non-fecal animal byproducts including animal mortalities, or table waste, alone or in combination.” In addition to manure and compost, examples of BSAAO include bone meal, blood meal, fish emulsion, and post-consumer food waste (such as plate scrapings).
Biological Soil Amendments of Animal Origin (BSAAO) Requirements and Best Practices
Let’s look at some of the requirements in the PSR as they pertain to BSAAO. Keep in mind that the PSR only applies to farms that are covered under the rule, but best practices can be used by all produce growers.
- Rule requirement: You must handle, convey and store any BSAAO in a manner and location such that it does not become a potential source of contamination to covered produce, food contact surfaces, areas used for a covered activity, water sources, water distribution systems, and other soil amendments. See 21 CFR §112.52(a).
- Best practices: Whenever possible, keep manure, compost, or other BSAAO piles under cover and protected from rain, wind, and wildlife. Store BSAAO in a location that will not cause risks of runoff or leachate, e.g. by locating piles downslope or far away from produce growing areas. Use dedicated equipment and clothing when handling BSAAO and/or clean equipment and clothing after working with BSAAO to prevent cross contamination.
- Rule requirement: Untreated BSAAO must be applied in a manner that does not contact covered produce (produce subject to the PSR) during application and minimizes the potential for contact with covered produce after application. See 21 CFR §112.56(a).
- Best practices: If you plan to use untreated BSAAO for growing covered produce, make sure to apply BSAAO in a manner that does not contact the crop during application, and that either minimizes or does not contact the crop after application. For example, a farm may choose to incorporate untreated manure or compost to a field in the fall, which will then be planted the following spring with a crop such as peppers, tomatoes, or trellised peas that do not have a harvestable portion that comes into direct contact with the soil. The farm may also choose to grow the crop on plasticulture to further reduce the risk of contact between an untreated BSAAO and the harvestable part of the crop.
- Rule requirement: BSAAO treated to the standard in 21 CFR §112.54(a) can be applied in any manner, as long as that BSAAO is stored, conveyed, and handled so as not to become a source of potential contamination, and the farm keeps annual records from the supplier to document the product underwent a scientifically valid treatment process that meets the microbial standards in 21 CFR §112.55(a).
- Best practices: Use a treated BSAAO to side dress a crop if the amendment is likely to contact the crop during application. For example, a farm may determine that they cannot reliably side dress a brassica crop in a way that minimizes potential contact with the crop, and therefore chooses to purchase a BSAAO fertilizer, such as heat-treated poultry manure, from a company that processes the BSAAO with a scientifically valid treatment process. The farm keeps the required annual records from the supplier to document that the BSAAO fertilizer meets the appropriate scientifically valid treatment standards.
Many farms are already following parameters similar to these that are established by certifying bodies like the National Organic Program and the USDA Good Agricultural Practices (GAP) program. These programs typically require a harvest interval between when manure is incorporated in a field and when the crop can be harvested. Ongoing research by the FDA and other organizations supports the concept that the risk from potential contamination is lowered by an application-to-harvest interval. The FDA is conducting further research trials to determine whether a specific application-to-harvest interval is appropriate for untreated BSAAOs used to grow covered produce.
Whether you are a large farm spreading amendments on your fields, or a hobbyist with a small garden, there are ways to decrease the food safety risks associated with using biological soil amendments of animal origin. Safe handling, storage, and application practices can help ensure fresh produce continues to be safe to consume raw. For more information on best practices, potential risks, and regulatory guidance, visit the Vermont Agency of Agriculture’s Produce Program website at agriculture.vermont.gov/produceprogram .
Questions? If you are a Vermont produce farm and need assistance in determining whether your farm is subject to the FSMA Produce Safety Rule, or would like further information on produce safety best practices, contact the Produce Program at AGR.FSMA@vermont.gov or (802) 511-3132.
1 The full text of the FSMA Produce Safety Rule, including definitions and requirements, can be found at go.usa.gov/xmpKH (case-sensitive URL).