The plan is for produce grown in fields or other growing areas and the use of untreated biological soil amendments of animal origin (BSAAO).
Typical examples of untreated BSAAO are raw cattle manure, poultry litter, swine slurry, and horse manure and it can be with contaminated enteric pathogens such as E. coli O157:H7 or Salmonella.
It will evaluate the impact of certain interventions, such as use of a time interval between application of the soil amendment and crop harvest, on predicted risk.
Risk assessment to inform policy
The notice was published in the Federal Register and comments close on May 3 and the risk assessment is to inform policy decisions.
Produce farms use untreated BSAAO because they are inexpensive, readily available, and rich nutrient sources for growing crops.
“Whether it is feasible for a farm to use untreated BSAAO as a principal nutrient source depends on numerous factors, including whether there is a required time interval between application and harvest and the length of such an interval (which may affect the nutrients retained or available from BSAAO), and crop nutrient demand (i.e., the nutrients needed to support crop growth),” said FDA.
The agency acknowledged that required application intervals for certain uses of untreated BSAAO could influence the number of crop cycles for a farm each year and/or the choices farms make regarding which type of amendment to apply.
Produce safety rule decision
The Produce Safety Rule of the Food Safety Modernization Act (FSMA) establishes there is no minimum application interval required when untreated BSAAO are applied in a way that does not contact covered produce during or after application.
Minimum application interval is [reserved] when applied in a manner that does not contact produce during application and minimizes the potential for contact with produce after application.
The proposed rule included a 9-month minimum application interval for untreated BSAAO but was withdrawn in response to public comments.
This was due to the limited scientific evidence relating to the proposed 9-month interval and the need for additional research in this area, said the agency.
Some comments expressed concern that animal habitat, habitat connectivity, and wildlife populations would be at risk if the provisions related to animal intrusion were perceived by produce growers to mean that less habitat and/or more fencing in the production environment is a necessary management strategy.
The risk assessment will look at data and information on the initial prevalence and levels of pathogens in untreated BSAAO; the methods used to apply untreated BSAAO to soils; pathogen survival (and growth) in untreated BSAAO and soils amended with untreated BSAAO.
Pathogen transfer to produce grown in amended soils; pathogen survival and growth on produce; and pathogen survival, growth, and cross-contamination during storage and other steps in the supply chain (e.g., washing) will also be assessed.
It will characterize the variability and uncertainty of pathogen survival and growth under different agricultural and ecological conditions (e.g., soil types, application methods, or geographic locations/climatic factors) and time intervals between application of untreated BSAAO and crop harvest.