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Chapter 19

Regulatory Perspective on Enhancing the Safety of Foods Needs and Challenges

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Sean Altekruse and Daniel Engeljohn Office of Policy, Program, and Employee Development, Food Safety and Inspection Service, U.S. Department of Agriculture, Cotton Annex Building, 300 12 Street, SW, Washington, DC 20250-3700 th

Most food safety hazards are invisible to the eye; however, federal food safety laws, which date back a century, emphasize removing recognizably unwholesome foods from the marketplace. These laws prescribe how, where, and when food inspections are to be performed. Current understanding of the natural history of foodborne pathogens supports a more integrated (farm to table) food safety strategy. In the 1990s, Hazard Analysis Critical Control Point (HACCP) regulations were developed to delineate the appropriate food safety responsibilities of industry and government. In the 21 century food safety agencies will need to continually invest in scientific infrastructure and maintain an expert workforce to prioritize and manage evolving foodborne hazards. Appropriate levels of funding and recruitment are essential to accomplish these goals. st

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U.S. government work. Published 2006 American Chemical Society

In Advances in Microbial Food Safety; Juneja, V., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 2006.

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1. Historical Context U S D A ' s Food Safety and Inspection Service (FSIS) has regulatory responsibility for the safety of meat, poultry and egg products and the Food and Drug Administration (FDA) is responsible for assuring the safety of most other foods. The enabling laws for both agencies were written in 1906, the year in which Upton Sinclair published "The Jungle," (7) a novel decrying sanitary conditions in turn-of-the-century slaughter plants. The 1906 Food and Drug Act (2) and Federal Meat Inspection Act (3) reflected a social context of the early 1900s that associated "adulteration" of food with human disease (4) The statutes contain parallel language prohibiting "adulteration" of food with a poisonous or deleterious substance which may render it injurious to health or any filthy, putrid, or decomposed substance that is unsound, unhealthful, unwholesome or otherwise unfit for human food. Although both laws were substantially revised in 1938 and 1967, the term "adulterated" remains the basis for both FSIS' and F D A ' s authorities, and does not fully reflect the natural history of most foodborne infectious diseases. Many foodborne hazards of the early 21st century are caused by microscopic pathogens (e.g., Salmonella, Campylobacter) that have no effect on the appearance of food or health of animals and plants (5) FSIS has classified only a handful of pathogens as adulterants, which are not permitted in foods (e.g., E. coli 0157 in ground beef, Listeria and Salmonella in ready to eat foods, B S E infected cattle tissue). The brevity of the list indicates the resistance to declaring pathogens as adulterants.

The FDA System Under the F D A system, companies are legally responsible for producing foods that are not adulterated. In 2000, the agency had a workforce of approximately 250 food inspectors who were responsible for inspecting tens of thousands of food operations. Since it is not possible to inspect all plants on even an annual basis, instead F D A uses regulations and guidance to inform food companies of their requirements to produce foods that are not adulterated. F D A conducts discretionary inspections based largely upon need. Regulatory options to remove adulterated foods from the marketplace include voluntary recall by the food manufacturer. Like FSIS, in cases of noncompliance with an F D A requested recall, the F D A can initiate a court action to seize a food product or direct the producer to stop manufacturing it (5, 6). This approach works well almost all of the time since the vast majority of food producers take their food safety responsibilities very seriously. On rare occasions, problems occur when companies fail to meet their obligations or


288 when emerging food safety hazards are first recognized. One example was the delayed response to Salmonella Enteritidis contamination in eggs. Applied research was needed to determine how to detect contaminated flocks and what interventions would prevent human illnesses. Only after agency responsibilities were clearly established did F D A begin to test flocks implicated in human outbreaks. This action provided an incentive for egg producers to implement controls and was followed by a decline in human Salmonella Enteritidis infection rates (7).


The FSIS System The FSIS system requires a critical inspection of every animal carcass that is destined for human consumption by touch, feel, and smell; a process referred to as organoleptic inspection. Daily inspection is also required in food operations that manufacture food products containing meat. To meet these requirements, FSIS employs approximately 7600 inspectors in 6500 plants across the nation. Plants that produce adulterated meat or poultry products can have the FSIS mark of inspection withheld, precluding interstate commerce (5). As the role of pathogenic microorganisms in foodborne infections was recognized over the past century, it became clear that there was a need to shift from organoleptic to science-based inspection to address foodborne hazards of meat and poultry. Specifically, the leading foodborne pathogens in meat and poultry (i.e. Campylobacter, Ε coli 0157:H7, and Salmonella) often colonize the intestines of healthy animals and are not detectable by visual inspection (4). In the worst cases, the U S D A mark of inspection may have provided a crutch for plants that chose to avoid responsibility for their sanitation and food safety programs (5) After FSIS was criticized for not declaring E. coli 0157:H7 to be an adulterant of ground beef, HACCP-based regulations were developed, signaling a new emphasis on industry food safety responsibilities. The evolving view of meat inspection emphasizes preventing distribution of meat and poultry containing high loads of pathogens capable of affecting humans. Ultimately, inspection could provide an opportunity to inform suppliers and producers of hazards and to encourage best food safety practices prior to slaughter and processing, (8) including on-farm H A C C P (epidemiological) programs to manage risk (P).

Fragmented Federal Authority A 1993 report (70) estimated that at least 12 federal agencies enforce 35 statutes involving food safety. These include agencies with oversight of school



289 lunch programs, seafood inspection, and International Passenger Vessel Sanitation. The fragmentation of responsibility has contributed to delays in the past like the emergence of Salmonella Enteritidis contaminated eggs, mentioned above. After C D C reported a threefold increase in human infections (77) associated with internal contamination of eggs (72) in 1988, a decade passed before a decline in human infections became evident (75). Initially U S D A ' s Animal and Plant Health Inspection Service addressed the problem as an animal disease. B y the mid 1990s, F D A took the lead in testing egg laying flocks that were implicated in outbreaks of Salmonella Enteritidis infection. There are many similar examples of close jurisdictional boundaries. For example, U S D A inspects pepperoni pizza and open faced meat sandwiches while F D A inspects cheese pizza and meat sandwiches with two pieces of bread. There have been proposals to consolidate food safety programs into one agency to improve use of resources, consistency of strategies, and accountability; (14) however; pressure has not existed for such complete restructuring. Many officials and advocates recommend change within context of the laws of existing food safety agencies. This is the context in which H A C C P regulations evolved.

International, State and Local Agencies Local agencies, foreign governments, and international agencies have major roles in food safety policy. The economic clout of foreign nations was evident when the United States major trading partners banned the importation of beef from the United States in December 2003 after a case of B S E was reported in Washington State. The market for more than one tenth of United States beef immediately disappeared. International agencies (e.g., World Trade Organization) seek to harmonize food safety standards so that foods meet equivalency requirements (6) and avoid trade barriers (75). Federal agencies work with state and local officials to formulate the Federal Model Food Code (16), which serves as a guide for state and local law. State and local agencies also participate in cooperative programs to assure that eggs, milk, shellfish, and other food commodities meet minimum food safety standards. Typically, it is county and municipal authorities that license groceries and restaurants or close retailers because of sanitation problems or outbreaks.

Epidemiology and Regulation The Centers for Disease Control and Prevention (CDC) is the federal agency with lead responsibility for foodborne disease surveillance. F D A and FSIS use these data to develop strategies and evaluate the effectiveness of programs. The



290 interest in epidemiological data is evident in F D A and FSIS collaborations with C D C and states on surveillance programs such as FoodNet (77) and the National Antimicrobial Resistance Monitoring System (NARMS) (18) and laboratory subtyping (PulseNet) (19). C D C also assists with outbreak investigations at the invitation of states. Often, food safety agencies conduct parallel studies to understand factors that contribute to outbreaks (20, 27). As other examples of circular consultations, C D C epidemiologists consult with regulatory officials to gain in-depth knowledge of specific food industries and F D A and FSIS rely on findings from outbreak investigations to guide sampling and regulatory actions (e.g., recalls). Epidemiology has steadily evolved with society since the mid 1800s, when John Snow investigated a cholera epidemic in London (22). Thus, in the 1950s, the church ice cream social was a typical foodborne outbreak scenario. It was often possible to infer the source o f illness because people knew each other and had eaten together. With the advent of mass food distribution, a new outbreak scenario began to occur, in which patients did not know each other and were geographically dispersed. For example, in 1994 an outbreak of salmonellosis was associated with ice cream that became cross-contaminated when ingredients were hauled in tankers that had carried unpasteurized eggs. The ice cream was delivered to homes throughout rural America (23). Critical elements for investigating this outbreak included laboratory subtyping to discriminate outbreak-associated-infections from background-infections and interviews with cases and controls (healthy people) to identify the source. Regulatory agencies have become increasingly at ease with epidemiology as a basis for enforcement action. In the early 1990s, F D A required microbiological confirmation before acting on epidemiological evidence; however, after a 1996 outbreak of cyclosporiasis (24), F D A banned import of implicated Guatemalan raspberries based solely on a statistical association between exposure and illness. The pathogen was never found in berries because it was present at low levels, unevenly distributed, did not grow on standard media, and was not detectable — even with sensitive testing methods (e.g., polymerase chain reaction).

2. New Approaches for New Problems The 1993 Outbreak of 2?. coli 0 1 5 7 . Ή 7 in Seven Western States A major event in the United States food safety system was the 1993 outbreak of E. coli 0157:H7 infection (25) linked to a fast-food hamburger chain. With approximately 500 confirmed infections, 41 cases of hemolytic uremic syndrome (mainly in young children), and at least four deaths, (26) the outbreak strengthened calls for meat and poultry safety reforms. The existing



291 balance of responsibilities for food safety among consumers, industry, and government was immediately called into question (5). Industry had maintained that raw products were not intended to be pathogen free and it was the responsibility of consumers to cook them so that they did not cause illness (4). Contamination of ground beef with Ε coli 0157 presented a new and unacceptable health hazard. This low dose pathogen (21) caused severe illnesses and deaths in children who ate hamburgers that were pink at the center, an accepted behavior reported by 29% of U.S. adults in 1993 (27). The outbreak triggered demand for safe ground beef, regardless of cooking practices. The shift in responsibility to industry and government was a major impetus for FSIS and F D A to develop Hazard Analysis Critical Control Point (HACCP) regulations. The outbreak heightened awareness of many food safety challenges and opportunities. A decade later it continues to influence the food safety agenda pertaining to animal production, risk assessment, consumer outreach, marketbased incentives, research and infrastructure.

HACCP Hazard Analysis Critical Control Point (HACCP) programs for meat, poultry (28) and seafood (29) emphasize the distinct responsibilities of manufacturers and government for food safety. The intent of H A C C P is to delineate these responsibilities based on appropriate roles. Companies are responsible for producing safe foods and government provides oversight of these processes. This approach is a departure from the historical food safety relationship of industry and government, in which companies produced the food and food safety agencies inspected them for safety. Limitations of the previous approach were made evident by limited resources within F D A and FSIS and delayed action on emerging foodborne pathogens. Under H A C C P , companies determine which hazards are likely to occur in their products and where those hazards are introduced. Controls are developed to address these hazards, and validated monitoring schemes are used to ensure that the system works. Government officials review H A C C P plans and verify performance standards to assure that companies meet minimum food safety expectations (4). Under H A C C P , FSIS shifted its role from prior-approval of blueprints, sanitation and equipment. H A C C P rules require industry to provide data documenting that their equipment, facility, and food safety system is appropriate and adequate. Managers decide how a plant operates. Federal inspectors verify that the plans are appropriate, that written procedures are followed, and that the company meets minimum performance standards. Most producers have accepted H A C C P . Only a few plants have failed to develop H A C C P plans that define hazards and control points. On the other hand,



292 some producers have resisted full use of H A C C P as an iterative tool to improve food safety process on a continual basis. A n assessment of the reasons (or excuses) offered by industry for resistance to H A C C P identified three basic categories: fear of repercussions, calls for more science, and cost (30). Since 2001, both F D A and FSIS launched mid-course review/in-depth H A C C P verification efforts (of seafood and beef grinding establishments, respectively) to bolster compliance with H A C C P regulations. Regulatory agencies need to anticipate change (e.g scientific advances and new public policies). As industry performance improves, new pathogens emerge, new technology is developed, and court decisions demand; it may be necessary to revise performance standards that were established to assure that establishments are in complianc with requirements of H A C C P regulations.

Animal Production The National Academy of Science has recommended on-farm programs to control foodborne hazards (57); however, FSIS does not have regulatory authority over animals before they arrive at slaughter plants. Cooperative approaches are therefore needed to address the microbial quality of feed and water, sanitation, and pest control (8). The advent of animal identification technology (32) may allow animals with optimal food safety risk profiles to be processed in advance of other animals (55). This approach would introduce new incentives for best production practices. For example, restrictions could be placed on the use of carcasses with high pathogen loads (e.g., use for cooking). In addition, verification sampling at the processing level would provide data to suppliers and producers for food safety assurance and/or improvement.

Risk Assessment Risk assessments are required by the Office of Management and Budget for economically significant regulatory decisions to assure that policies are sound and cost-effective. Legislation passed in 1994 that created the Office of Risk Assessment and Cost Benefit Analysis, charged with reviewing food safety regulations to assure that they are based on sound analysis of risks, costs and benefits. Epidemiological and experimental data are used in risk assessments in the development of new policies. Epidemiological data is valued in risk assessments because it reflects experience (e.g., associations from case-control studies), provides data on trends and the burden of illness, (34) infectious dose, (27) and attributable risk (55). Experimental data provide additional insight into


293 issues including the ecology of a pathogen, virulence, strain diversity, and host specificity.


Consumer Outreach Consumer surveys are used to develop consumer outreach on foodborne disease prevention (e.g., recommendations to clean, cook, separate, and chill) and to measure the effectiveness of interventions (36). Surveys are also used to identify groups with high rates of risky behavior (24) and estimate the proportion of the population that is predisposed to infection by underlying disease (37). The best surveys use well designed questionnaires, sampling, and analytic methods.

Market Based Incentives The marketplace provides economic incentives for food producers to conduct food safety monitoring (38). B y demanding product testing and process controls, large fast food restaurant chains have created a market in which the microbial safety of ground beef is paramount. International trade has also stimulated food safety markets. Foreign buyers who demand high safety standards and pay premiums for guaranteed contracts have fueled demand for ground beef with the highest safety assurance. B y securing these reliable contracts, meat processors realize benefits for their investments in food safety technology. Government can raise industry food safety standards through policies that build on these market incentives. Indeed, the combination of market and regulatory forces may have contributed to a recent decline in human infections caused by Ε coli 0157:H7 in the United States (39).

Research and Infrastructure Food safety agencies must invest in their own scientific infrastructure to signal commitment to their mission and encourage innovation by industry. The simultaneous revolutions in information technology and molecular biology illustrate the need for continuous workforce development. Food safety agencies need an expert workforce for 21 century inspection, H A C C P verification, to subtype pathogenic bacteria, and support epidemiological/environmental investigations. A skilled multidisciplinary team is also necessary for risk assessment model development, consumer outreach, and implementation of new food safety technologies for production and processing. st


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Food safety policies have enormous influence on research priorities within the scientific community. B y communicating policy and research needs, agencies generate interest and encourage funding for applied research. A s an example, after FSIS classified Ε coli 0157:H7 to be an adulterant of ground beef in October 1994, the number of PubMed "hits" for the search term "E coli 0157" dramatically increased (from 45 in 1994 to greater than 300 per year from 1999 through the present). Research progressed on topics ranging from Ε coli 0157:H7 ecology (40) to interventions for cattle (41). In addition, the time to obtain Ε coli 0157 test results decreased from 3-5 days to 1-2 days (42).

Priorities New food safety hazards are continually being identified, increasing expectations for regulatory agency action. In some instances foods have both beneficial and adverse effects (e.g., fish can be contaminated with methyl mercury or dioxin and is also the principal source of omega-3 fatty acids that reduces the risk of heart disease). Examples of pathogen/food combinations hint at the diversity of hazards (e.g., Vibrio in raw seafood, Cyclospora in berries). Chemical hazards include drugs, hormones, dioxin, and acrylamide. With the concerns over terrorism, food security has become a new and expensive federal priority. While agencies must address the microbial safety of processed foods, they also need to consider the role of these foods in epidemic obesity, which is rapidly becoming the leading cause of preventable death in the United States. Prioritizing these complex and sometimes conflicting public health problems requires data, judgment, and other tools of relative risk management.

The Future This report provides a brief regulatory perspective of some needs and challenges to assure the safety of the food supply. Experience indicates that new foodborne hazards will continue to emerge (43-46). A t the time that this report is being written, antimicrobial resistant Salmonella strains including S. Newport and S. Typhimurium has become a new issue for which FSIS is actively considering a variety of outreach, enforcement, and regulatory options - all of which involve the allocation of new resources and infrastructure. Government must continually work with consumers and industry to enhance food safety. In order to respond to constantly evolving challenges, food safety agencies must have adequate resources, infrastructure and data to prioritize current and future food safety challenges. Appropriate levels of funding and recruitment are essential in order for food safety agencies to effectively respond to the increasing


295 demands and expectations of the public and food industries for food safety assurance.

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