By De Ann Davis, SVP, Science and Gustavo Reyes, Sr Manager, Data Analytics and Food Safety

Cantaloupes have been linked to multiple foodborne illness outbreaks in the U.S. and Canada over the last 30 years. There have been numerous U.S. Department of Agriculture (USDA) and Center for Produce Safety (CPS) research projects, rising investment in industry training programs, changes in harvest equipment design as well as improvements in field practices. Additionally, over the past two years, a revised national standard for the growing, harvesting and packing of cantaloupes was developed. The comment period for the final draft concluded earlier this summer, with the leadership of Western Growers, cantaloupe growers from across the U.S., academic experts and public health representatives.

In the Fall of 2023, a significant Salmonella foodborne illness outbreak occurred linked to the Malichita and Rudy brand cantaloupes grown in the Sonora region of Mexico. This outbreak was represented by 407 illnesses, 158 hospitalizations and six deaths, reported between October 15 and December 25. A recent research article by Canadian public health researchers, Megan Rose-Martel and Sandeep Tamber, reviewed several cantaloupe outbreaks, including the 2023 outbreak:

A similar number of outbreaks and cases was attributed to cantaloupes grown in both the United States (5 outbreaks, 800 cases) and Mexico (5 outbreaks, 776 cases). However, a disproportionate number of hospitalizations (255 vs 126) and deaths (17 vs 3) were linked to cantaloupes imported from Mexico, though the importance of Mexican imports reflects a large outbreak that occurred in 2023 and potentially the dominance of Mexico as a source of cantaloupe consumed in the United States.

Before we go any further, it is important to note that the domestic supply of cantaloupe as part of total market availability has been steadily decreasing, down about one-third over the last two decades, leaving imports to fill the supply gaps. Historically, Mexican cantaloupe was as high as 25 percent of the cantaloupes imported into the U.S; in 2024 it was down to 9.2 percent. Guatemala is rising as the major exporter of cantaloupes to the U.S. with more than 56 percent market share in 2024.

Back to a review of the 2023 outbreak, looking at the publicly available information on the FDA investigation, the following actions were noted:

• FDA and CDC completed traceback investigations in collaboration with Canadian authorities and identified the suppliers for contaminated cantaloupes. FDA had in place Import Alert 22-01, allowing for the detention without physical examination of cantaloupes from Mexico, except from firms on the “Green List.” This Import Alert was updated on April 14, 2025.
• Mexican health authorities temporarily closed a melon-packing plant in Sonora that was implicated in the outbreak (news article).
• The FDA did not provide information in its investigation report on the outbreak regarding on-site investigations at the farms where the cantaloupes were grown, food safety non-compliance findings at the Mexican packing plant that was temporarily closed, nor if the Foreign Supplier Verification Programs (FSVP) of the importers of the cantaloupes were inspected and any non-compliances noted.

In the Summer of 2022, there was a Salmonella outbreak linked to cantaloupe grown in southwest Indiana. This outbreak occurred between July and September and was represented by 87 illnesses, 32 hospitalizations and no deaths. It was identified by the FDA as part of a reoccurring pattern of outbreaks linked to melons from that region (2012, 2020, 2022).

Prior to the 2022 outbreak, Indiana supplied about 6 percent of U.S. cantaloupes. That estimate is now about 1 percent. The FDA outbreak investigation for the 2020 outbreak was detailed in journal article published in 2023. Here’s what the investigative response to the 2022 outbreak included:

• Traceback investigations led to three common farms and packing houses in a common region of Indiana. These sites were inspected by FDA inspection personnel.
• Environmental samples were collected of growing sites, packing houses and other equipment. Whole-genome sequencing (WGS) was completed for the pathogen positive samples and submitted to the NCBI database.
• In addition, the FDA launched a multi-year longitudinal study in partnership with Purdue University and regional agricultural stakeholders to better understand potential pathogen ecology in this agricultural region.

When we compare what we understand as the agency’s response to both outbreaks, there is quite a difference in how the agency utilized its authorized regulatory tools to investigate, communicate and prevent reoccurrence of future outbreaks at the domestic farms versus the farms and packing houses in Mexico.

The domestic growers in Indiana experienced on-site inspections and environmental swabbing for pathogens throughout their operations. The producers in the region are now cooperating with the FDA in an environmental study of pathogen transmission, and those still growing cantaloupes will need to invest money to address findings. These producers will also need to continuously manage the land value risks associated with the pathogen WGS now linked to their farms. As I mentioned earlier, it’s worth noting that production in the southwest region of Indiana now represents only 1 percent of the cantaloupe market in 2024, down from 6 percent prior to the outbreaks.

The Mexican growers in the Sonora region, a region also known for repeated melon-related outbreaks, does not appear to have to manage these same economic circumstances and risks. FDA and Servicio Nacional de Sanidad, Inocuidad y Calidad Agroalimentaria (SENASICA) have a Memorandum of Understanding (MOU) for the purpose of establishing a system that increases the likelihood that cantaloupes from Mexico offered for import into the U.S. complies with U.S. law. The MOU lays out a tiering scale for firms based on whether firms (farms) have been implicated in an Outbreak, had shipments test positive for Salmonella or neither.

In brief, the firm’s handling under Import Alert 22-01 is determined by its tier and if SENASICA has certified the firm. Under the current Import Alert, some firms are greenlit or exempted from the Import Alert 22-01.

Based on available information, it’s unclear why the FDA did not impose additional regulatory measures on Mexican cantaloupe imports, such as the use of its Import Certification Authority, despite the region’s history and the severity of the outbreak, similar to actions recently taken for shrimp and spices from Indonesia. It did, though, add additional record reviews at the border for “yellow light” firms.

Another consideration would have been to ensure isolates and WGS from cantaloupes of the Sonoran region are provided to the National Center for Biotechnology Information (NCBI) database when they test positive for Salmonella at the border (perhaps this is being done). Capturing these paired pathogen WGS would help to quickly narrow investigations earlier in a foodborne illness outbreak investigation.

Cantaloupe imported from Mexico still represent about 9 percent of the U.S. market, having not experienced a similar almost complete loss of market share as southwest Indiana following that region’s outbreak. Assuring a strong and focused prevention regulatory system for these imported Mexican cantaloupes seems warranted as we focus on improving consumer consumption of fresh produce.

To prevent the recurrence of foodborne illnesses, our public health authorities must investigate and respond equally to domestic and foreign farms following an outbreak or significant food safety finding. The agency cannot potentially provide an economic or regulatory advantage to foreign farms, especially those in a region known to be associated with outbreaks. Foreign farms and their supply chains need to invest in the same necessary food safety improvements and FSMA compliance costs as expected of domestic operations and necessary for food safety. FDA should assure that foreign, including Mexican cantaloupe growers, have completed these investments in testing, equipment, training and field practices and that these changes are reflected in the records required for import. After all, Mexico still supplies a strong share of the U.S. market, and we import over 40-45 percent of all our cantaloupes.

We must hold foreign fresh fruit and vegetable supply chains equally accountable to grow, pack and ship safely and consistent with the FSMA regulations. This requires equitable enforcement, accountability and consequences from the FDA for foreign farms, their supply chains and importers.

Increased consumption of fresh fruits and vegetables requires a compensatory focus on food safety to avoid an overall increase in foodborne illness. Currently, the U.S. imports approximately 50 percent to 60 percent of its fresh fruits and about 40 percent of its fresh vegetables, reflecting a steady, decades-long decline in domestic production. This requires our public health authorities to enact clear proactive, prevention-based strategies for both domestic and imported fresh produce to assure safety.

For the domestic fresh produce supply chain, the Food and Drug Administration (FDA) directly oversees and enforces compliance with rules and regulations for safe production.  Domestic farms, harvesting, packing and storage operations are subject to inspection.  Under FDA inspection, these operations may be sampled for pathogens, noncompliance with regulations noted and inspection observations posted publicly.  For those operations with significant noncompliance observations during an inspection, or repeated noncompliance observations, the agency may issue a Warning Letter.

For imported fresh produce, the FDA regulatory system has basically two goals:

• Address potential food safety issues before the food reaches the U.S.
• Ensure that imported food is produced in accordance with the same safety standards as domestic production.

To accomplish these goals, the agency relies heavily on importers through the Foreign Supplier Verification Program (FSVP), third-party audits, and international regulatory agreements and collaborations to ensure foreign produce companies are complying with U.S. regulations. FDA also can inspect foreign farms, however, for various reasons, the agency has inspected very few foreign farms (no specific numbers were verifiable).

The FDA has no inventory of farms in foreign countries that export fruits and vegetables to the U.S., and there is no requirement for registration or other notification for a foreign farm prior to import. The FDA has also failed to meet its mandated inspection schedule, both domestically and internationally. The January 2025 U.S. Government Accountability Office report on food safety noted that the FDA conducts far fewer foreign inspections versus domestic inspections.

In 2023, the agency completed approximately 11,000 domestic inspections compared with 1,500 foreign inspections. Domestic farms must be prepared for FDA inspection and respond to observations often with economic investment. Because of resourcing, government agreements and other reasons, foreign farms do not have the same expectation of direct FDA oversight, regardless of the risk of the commodity or growing region.

The FDA also uses sampling of fresh produce as part of its efforts to keep contaminated products from reaching consumers and to facilitate a greater understanding of hazards. The FDA’s surveillance sampling assignments generally target commodities in domestic regions and include collecting samples from farms, packing facilities, coolers, warehouses or retail.

For domestic fresh produce operations, surveillance sampling assignments can be costly and disruptive to business, especially when conducted in the field or pre-shipment. For sampling of imported produce, samples are generally collected at ports of entry, warehouses and distribution centers; however, samples are rarely collected from farms or pre-shipment.

As previously stated, the FDA relies heavily on importers as the party responsible for ensuring their foreign suppliers are following the appropriate food safety regulations.  However, there is strong evidence that FSVP, as an import control, is not working to protect consumers as intended. A review of the 361 food-related Warning Letters written by the agency between 2020 to 2025, 81 (22 percent) were to importers of fresh produce for non-compliance with FSVP.  This data would indicate that there is a systemic compliance issue with importers of fresh produce that should be actively addressed by the agency given the importance and risk level of the food category.

FDA has the authority to do more. The agency, for example, could place non-compliant importers on Import Alert, seek to bar repeat offenders from being allowed to import food into the U.S., or impose re-inspection fees on importers whose products fail inspection at the border. The absence of meaningful consequences for importers with significant FSVP failures can be providing foreign farms with an economic advantage over domestic growers. Foreign farms would not always need to make the same monetary investments as domestic farms to demonstrate compliance with food safety regulations, if demonstrating compliance is not consistently enforced at the border.

FSMA also authorizes the FDA to require third party certifications, or other assurances as deemed appropriate, for specific types of imported food based on public health considerations. The FDA recently used this authority for the first time for shrimp and spices from certain regions of Indonesia. These certifications or assurances can be provided in the form of shipment-specific certificates, a listing of certified entities, or in another form specified by FDA. The agency could leverage the use of these certificates to provide greater oversight over imported fresh produce, especially following a food safety event or when other public health considerations are met, such as a growing region of concern. The use of this authority would also help subject foreign farms to the similar compliance rigor as applied to domestic farms.

There are known fresh produce items and fresh produce growing regions that have been associated with repeated food safety concerns, both foreign and domestic. In response, domestically, the FDA has provided public prevention strategies, such as the Leafy Greens STEC Action Plan or published in-depth outbreak investigation reports. However, for imported produce, the publicly available information regarding prevention strategies following a food safety event is limited, infrequent or silent. For example, the public may be made aware of an updated Import Alert, as in the case of cantaloupes from Mexico, but there was little other accompanying information to explain the investigation outcome or steps taken to improve safety of the cantaloupes being imported.

For domestic growers, these public investigation reports and prevention strategies set expectations with the supply chain, regulators and consumer advocates for programmatic improvements in food safety. The public should be provided with the same transparency and accountability for foreign farms and their supply chain following a foodborne illness outbreak as is provided for domestically sourced produce.

The FDA has various regulatory tools that it can employ to improve its oversight of imported fresh fruits and vegetables. Deployment of a strategic regulatory compliance program for imports that is risk-based (commodity, region, company), tracked for public transparency and enforced equitably, is necessary to ensure safety for U.S. consumers.

Domestic producers must not be placed at an economic disadvantage to their foreign competitors because of regulatory compliance costs that are not faced by their foreign competitors. Nutritional security for the U.S. is a public health priority. How food safety regulations are enforced should not undermine that priority.

According to Section 801 (21 USC 381) of the Federal Food Drug and Cosmetic Act (FFDCA), a product can be refused admission into the U.S. under certain conditions:

In sum, if it “appears from examination” that the product is:

• Produced under insanitary conditions
• Adulterated or misbranded
• The importer is not in compliance with Foreign Supplier Verification Program (FSVP)
• The recordkeeping requirements (including the traceability rule) have not been compiled

Certainly, a standard of “appears from examination” is a higher regulatory bar for foreign fresh produce than the domestic standard of “prohibited…from introduction or delivery for introduction into interstate commerce of any food … that is adulterated or misbranded.”  (Section 301(a) (21 U.S.C. §331(a) FFDCA).

However, there is a strong argument that the lack of Food Safety Modernization Act (FSMA) enforcement actions by the U.S. Food and Drug Administration (FDA) provides an advantage to foreign fresh fruit and vegetable producers and thus a net economic boost to those producers by the avoidance of associated regulatory costs and managing associated risks that domestic producers must bear.

Take, for an example, a scan of the 38 FSVP FDA Warning Letters issued in 2024; 19 of those letters were issued to importers of fresh produce or roughly 40 percent.

Going a bit further, the FDA’s Division of Southwest Imports alone wrote 10 of the 19 letters, showing more than half were for the southwest border crossings. This means these importers did not have the obligatory records necessary to support that the fresh produce that was actively being imported was compliant with the requirements of FSMA.

There are important examples of fresh produce importers that have received multiple FSVP inspections with significant non-compliant findings followed by a Warning Letter in the FDA’s database. These warning letters clearly state the importer was found to be non-compliant with Section 805 of the FFDCA, or the requirements of FSVP. The letters also demonstrate that the time period between the first FDA FSVP inspection and the issuing of the Warning Letter can span multiple years.

So, let’s think about that for a minute. An importer has more than once, by FDA inspection, failed to meet the requirements of Section 801 (21 USC 381) of the FFDCA because of noncompliance with FSVP. Yet, this importer apparently continued to import fresh produce without any significant regulatory consequence.

These Warning Letters argue that the FDA is not willing to use its full authorities at the border to protect public health by allowing non-compliant importers to bring potentially unsafe fresh produce into the U.S. (If the required records were not available, how does the agency know the imported fresh produce was safe?)

Secondly, it can also be argued that the foreign producers that supply to known non-compliant importers have an economic advantage because these producers would not necessarily, depending on the distribution channel for the items, need to provide any food safety records for the supply chain once they are in the U.S.  By contrast, virtually all domestic producers–except for potentially the very small producers–that place fresh fruits and vegetables with handlers, shippers or retailers and others in the supply chain, are required to provide food safety records. This results in higher food safety compliance requirements and costs for domestic producers when compared to foreign producers whose product enters U.S. supply chain through non-compliant importers.

If a member of the domestic supply chain for fresh fruits and vegetables were to receive an equivalent regulatory action, the following are likely additional regulatory actions that could result:

1) Site re-inspection with potential for fee collection, product pathogen sampling at field, harvest equipment, packing shed or processing facility. There would be costs to the producer related to sampling events as well as costs associated with remedying the record-keeping findings.

2) Potential supply chain actions related to Global Food Safety Initiative (GFSI) re-certification and lost business, at a minimum, until the findings of the Warning Letter are resolved.

This is not to say that the FDA regulatory non-compliant findings and associated costs are not appropriate and warranted. But aren’t the costs to remedy these findings also appropriate and warranted for foreign fresh produce growers, handlers/shippers and their importers? FDA Warning Letters to those in the domestic food supply chain have serious business consequences. The same does not seem to be true for FSVP non-compliant importers and their respective foreign supply chain. Maybe it should be.

Domestic production of fresh fruits and vegetables is on the decline in the U.S. because of many cost-driven factors with rising regulatory compliance costs being just one. If we all agree that supporting our current production in the U.S. is critical for the Nation’s nutritional security and helping to assure safe fresh produce, then we need to address the economic advantages of non-compliant foreign producers, including the lack of FSVP enforcement at our border.