One of the most common origins of foodborne illness outbreaks in the United States comes from the watering of agricultural produce with contaminated water. This occurs when water used to irrigate agricultural produce contains harmful pathogens which are then transferred to the edible portion of the plant. To combat this issue, the Food and Drug Administration (FDA) has published rules requiring testing of pre-harvest agricultural water. Specifically, on May 2024 the FDA published a final rule amending the provisions for pre-harvest agricultural water on covered produce other than sprouts as part of the 2015 “Standards for the Growing, Harvesting, Packing, and Holding of Produce for Human Consumption” rule. The updated rule requires covered farms to complete annual assessments that evaluate pre-harvest agricultural water by identifying potential conditions that might contaminate agricultural water, and enacting corrective or mitigation measures to combat the conditions that could cause contamination.

Background and timeline of rule

The Federal Food, Drug, and Cosmetics Act (FDCA) is the primary statute governing FDA’s food safety authority. In 2011, the Food Safety Modernization Act (FSMA) was signed into law to update the FDCA. FSMA was a landmark legislation because it shifted the nation’s food safety system from focusing on responding to foodborne illness to instead focus on preventing foodborne illness. In its implementation of FSMA, the FDA issued nine foundational rules, including the Produce Safety Rule (PSR). FSMA required the FDA to “to establish science-based minimum standards for the safe production and harvesting of those types of fruits and vegetables, including specific mixes or categories of fruits and vegetables, that are raw agricultural commodities for which the Secretary has determined that such standards minimize the risk of serious adverse health consequences or death.” 21 U.S.C. § 350h. The PSR works to establish those standards.

2015 rulemaking

To implement the FSMA requirement of establishing science-based minimum standards, FDA published a proposed rule in 2013 titled “Standards for the growing, harvesting, packing, and holding of produce for human consumption,” commonly referred to as the Produce Safety Rule. Finalized in 2015, this rule applies to “covered produce” including raw nuts, raw fruit, carrots, lettuce, spinach, onions, citrus, and more. Included in the final PSR is a section, Subpart E, that requires agricultural water to be safe and adequate for its intended use. Subpart E also included standards for microbial quality criteria based on the intended use of agricultural water. For pre-harvest agricultural water used on covered produce other than sprouts, the microbial water quality criteria consisted of a geometric mean of 126 or less colony forming units generic E. coli per 100 millimeters, and a statistical threshold value of 410 or less colony forming units generic E. coli per 100 millimeters. Essentially, this means that Subpart E establishes a maximum number of E. coli that could be present in water before the water is considered contaminated. Additionally, Subpart E establishes standards for collecting samples from irrigation sources, including untreated surface waters and untreated ground water sources.

2019 Extension of Compliance Dates

Following the 2015 final PSR, FDA received stakeholder feedback expressing frustration with the “one-size-fits-all” nature of the PSR. Stakeholders felt the rule did not sufficiently address the diversity present in agriculture, including the variety in water uses and availabilities. Because of the concerns of various stakeholders, FDA extended the compliance dates for Subpart E while it considered how to modify the rule.

2021 Agricultural Water Proposed Rule

In 2021, FDA proposed a rule to substantially change Subpart E. The proposed rule only changed the agricultural water requirements for farmers growing covered produce other than sprouts. This  rule does not affect the water used to grow sprouts, nor the water used in harvesting, packing, and holding all covered produce. This rule change is specifically for pre-harvest agricultural water used for growing non-sprout, covered produce. The proposed rule replaced the microbial quality criteria standards established in the 2015 rule with the creation of assessments for pre-harvest agricultural water. Following the 2021 proposed rule, FDA published an extension of compliance dates for Subpart E of the PSR in 2022. For a detailed description of the PSR background and the proposed 2021 rulemaking, click here to view NALC article “Focus on Food: FDA Publishes Proposed Agricultural Water Rule.”

Final Rule

Under the final rule, published May 6, 2024, the FDA revises Subpart E of the Produce Safety Rule to establish requirements for systems-based pre-harvest agricultural water assessments. Covered farms must complete the assessments and use their outcomes to identify potential hazards and make risk management decisions. The updated rule includes options for corrective and mitigating measures covered farms may use if their assessment outcomes necessitate it.

Assessments Factors

The following factors must be evaluated in the assessments to identify conditions that are reasonably likely to introduce known or reasonably foreseeable hazards into produce or food contact surfaces:

• Agricultural water systems. This factor includes the location and nature of the water source. For example, this looks at whether the water source is ground water or surface water. Next, this factor evaluates the type of water distribution systems. For example, looking at whether the water distribution system is open or closed to the environment. Last, this factor evaluates the degree to which the system is protected from possible sources of contamination. Sources of contamination could include other users of the water system, animal impacts, adjacent and nearby land uses related to animal activity, the application of biological soil amendments of animal origin (BSAAOs), or the presence of untreated or improperly treated human waste.
• Agricultural water practices. This factor includes evaluating the type of application method, such as an overhead sprinkler or spray, drip, furrow, flood, and seepage irrigation. Additionally, this factor evaluates the time interval between the last direct application of agricultural water and harvest of the covered produce.
• Crop characteristics. This factor evaluates the susceptibility of the covered produce to surface adhesion or internalization of hazards.
• Environmental conditions. This factor looks to the frequency of heavy rain or other extreme weather events that impact the agricultural water system or damage produce. Examples of impacts to the agricultural water system includes the stirring of sediments that may contain human pathogens. While damage to the produce is noteworthy because it could result in an increased susceptibility of produce to contamination. Last, this factor also looks at the impact of air temperatures and sun (UV) exposure.
• Other relevant factors. This factor provides covered farms with an option of incorporating other relevant factors to the assessment that may be unique to the circumstances of their operations. Additionally, this factor recognizes that there are other PSR subparts which include requirements for protecting agricultural water sources and distribution systems from contamination, and allows covered farms to include their compliance with those requirements in the assessment under this factor.

Assessment Outcomes

After conducting the pre-harvest agricultural water assessment and identifying potential conditions that might introduce hazards onto produce or food contact surfaces, covered farms are required to use assessment outcomes to determine the necessity of implementing corrective or mitigation measures. The determinations must be written and will require covered farms to take the following actions to reduce potential contamination of covered produce. First, if it is determined that agricultural water is not safe or is not of adequate sanitary quality for intended uses, then producers must immediately discontinue use and take corrective measures before resuming use of the water for pre-harvest activities. However, if producer determines there is one or more known or reasonably foreseeable hazards related to animal activity, BSAAOs, or untreated or improperly treated human waste on adjacent or nearby land for which mitigation is reasonably necessary, then they must implement mitigation measures promptly, and no later than the same growing season. Similarly, if it is determined there is one or more known or reasonably foreseeable hazards not related to animal activity, BSAAOs, or untreated or improperly treated human waste on adjacent or nearby land, for which mitigation is reasonably necessary, then they must implement mitigation measures as soon as practicable and no later than the following year, or test water as part of the assessment and implement measures, as needed, based on the outcome of the assessment. Last, if a producer determines there are not any known or reasonably foreseeable hazards for which mitigation is reasonably necessary, then they must regularly inspect and adequately maintain the water systems.

Corrective and Mitigation measures

Based on the assessment outcomes, and subsequent outcome determinations, there are several corrective or mitigation measures the covered farm will be required to implement. First, as a corrective measure, a covered farm must immediately discontinue use if it determines the pre-harvest agricultural water is not safe or of adequate sanitary quality for its intended use. To resume such use, a covered farm may take corrective measures, such as re-inspecting the entire affected agricultural water system under the farm’s control and making necessary changes or treating the water in accordance with the standards outlined in the PSR.

Similarly, if the covered farm determines mitigation measures are necessary, the covered farm may exercise any of the following options:

• Making necessary changes such as repairs.
• Increasing the time interval between the last direct application of agricultural water and harvest of the covered produce to allow for microbial die-off, with supporting scientific data and information.
• Increasing the time interval between harvest and the end of the storage period and/or conducting other activities during or after harvest to allow for microbial die-off or removal, with supporting scientific data and information.
• Changing the method of water application to reduce the likelihood of produce contamination (such as changing from overhead spray to subsurface drip irrigation for certain crops).
• Treating the water in accordance with the standards outlined in the PSR, or
• Taking alternative mitigation measures supported by scientific data and information.

Reassessment, Records, and Exemptions

Covered farms must conduct a pre-harvest agricultural water assessment each year the farm applies pre-harvest agricultural water to non-sprout covered produce. Additionally, if there is a significant change in the farm’s agricultural water systems, agricultural water practices, crop characteristics, environmental conditions, or other relevant factors that makes it reasonably likely that a hazard may be introduced into cover produce through direct pre-harvest agricultural water application, a covered farm will be required to complete a reassessment. Covered farms are required to maintain written records of their pre-harvest agricultural water assessments. Maintained records must include descriptions of the evaluated factors and the written determinations based on assessment outcomes.

The rule provides an exemption from conducting assessments for certain covered farms if they can demonstrate the following conditions. First, if the pre-harvest agricultural water for covered produce meets certain requirements that apply for harvest and post-harvest agricultural water, then the covered farm is exempt from conducting an assessment. Second if the pre-harvest agricultural water is received from a public water system or supply that meets requirements established in the rule, then the covered farm is exempt. Last, if the pre-harvest agricultural water is treated in accordance with the standards outline in the PSR, the covered farm is exempt from completing an assessment.

Compliance Dates

The final rule contains three compliance dates for three categories of covered farms. Covered farms that sold more than $500,000 of produce during the previous 3-year period has 9 months after the effective date of the final rule to comply. Small farms, or covered farms that sold more  than $250,000 but not more than $500,000 of produce during the previous 3-year period has 1 year and 9 months after the effective date of the final rule to comply. Very small farms, or covered farms that sold more than $25,000 but not more than $250,000 of produce during the previous 3-year period has 2 years and 9 months after the effective date of the final rule to comply. The effective date of the final rule is July 5, 2024.

Conclusion

After years of extending compliance dates and information gathering, the FDA published their final rule amending the pre-harvest agricultural water requirements in Subpart E of the Produce Safety Rules. The updated rule requires covered farms to annually assess their pre-harvest agricultural water by evaluating their agricultural water system, their agricultural water practices, the crop characteristics, the environmental factors, and other relevant factors. The rule requires covered farms to use the outcomes of their assessments to determine the necessity of corrective or mitigation measures to ensure potential contamination does not occur.

For more resources on Food Safety, click here to view NALC Food Safety Reading Room.

To read NALC Factsheet on the PSR, click here.

To view FDA Factsheet “FSMA Final Rule on Pre-harvest Agricultural Water,” click here.