Recalls of Foods due to Microbiological Contamination Classified by the U.S. Food and Drug Administration, Fiscal Years 2003 through 2011

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1 932 Journal of Food Protection, Vol. 76, No. 6, 2013, Pages doi: / x.jfp Recalls of Foods due to Microbiological Contamination Classified by the U.S. Food and Drug Administration, Fiscal Years 2003 through 2011 MANASHI DEY, 1 JONATHAN A. MAYO, 2 DEBORAH SAVILLE, 1 CECILIA WOLYNIAK, 1 AND KARL C. KLONTZ 1 * 1 U.S. Food and Drug Administration, 5100 Paint Branch Parkway, College Park, Maryland 20740; and 2 School of Public Health and Health Services, George Washington University, 202 Ross Hall, 2300 Eye Street N.W., Washington, D.C , USA MS : Received 17 October 2012/Accepted 8 February 2013 ABSTRACT Recalls of foods contaminated with pathogens help reduce the transmission of infectious diseases. Here, we summarize the number and nature of foods recalled as a result of microbiological contamination, classified by the U.S. Food and Drug Administration for the period 1 October 2002 through 30 September Microbiological contamination accounted for 1,395 (42%) of 3,360 recalls of food during this period. Nuts and edible seeds, followed by fishery seafood products and spices, were the types of products most commonly recalled for microbiological contamination. Salmonella contamination accounted for the greatest number of food products recalled due to microbiological contamination, and was the pathogen most often linked to reported outbreaks involving recalled food products. Each year in the United States, there are an estimated 9.4 million episodes of foodborne illness from 31 major pathogens, which results in 55,961 hospitalizations and 1,351 deaths (16). Although norovirus is the leading cause of foodborne disease, bacterial pathogens and/or their toxins commonly transmitted through food include Salmonella, Campylobacter, Clostridium perfringens, Clostridium botulinum, Staphylococcus aureus, and Shiga toxin producing Escherichia coli, including E. coli O157:H7. Only a subset of foodborne infections that actually occur are reported to local, state, and national surveillance systems (3). Recalls of foods contaminated with pathogens decreases the transmission of infectious diseases. Manufacturers and distributors voluntarily undertake recalls of products in violation of the Food, Drug, and Cosmetics Act, based on their own findings and/or those of public health agencies at the local, state, and federal levels. Prior to enactment in January 2011 of the Food and Drug Administration (FDA) Food Safety Modernization Act, with the exception of cosmetics and infant formulas, the Federal Food, Drug, and Cosmetic Act did not give the FDA authority to order a firm to recall a violative product. When a firm did not voluntarily initiate a recall, the FDA could request in writing that the firm recall the violative product, but such action was reserved for situations involving serious or life-threatening hazards. In the event a firm refused to undertake a recall when requested to do so by the FDA or when the FDA had reason to believe that a recall would not be effective, the * Author for correspondence. Tel: ; Fax: ; karl.klontz@fda.hhs.gov. FDA could initiate a seizure of the product and/or seek an injunction, and criminal prosecution could be initiated (1). Additionally, the FDA may issue press announcements to inform consumers about a potential hazard associated with a violative product. Firms are often willing to recall products to avoid regulatory action by FDA and any adverse publicity that might ensue. Over time, experience has shown that successful food recalls often involve the collaboration of multiple parties, including growers, manufacturers, distributors, consumers, and state and federal agencies (21). With enactment of the Food Safety Modernization Act, the FDA was given authority to order a recall of a food wherein the reasonable probability exists that an article of food is adulterated, and ingestion of the article will cause serious adverse health consequences or death. Although enactment of the Food Safety Modernization Act occurred in January of 2011, no FDA-mandated recalls of foods or cosmetics occurred during the final 9 months of the present study s period of assessment, 1 October 2002 through 30 September 2011 (the study period). While numerous published studies have described outbreaks of illness due to commercially marketed contaminated food products, few have characterized the types of foods involved in recalls and the pathogens present in recalled foods (19, 21). In a study of recalls of foods and cosmetics monitored by FDA from fiscal years 1994 through 1998, microbial contamination was found to be the leading cause of recalls, accounting for 1,370 (36%) of 3,793 of all foods and cosmetics recalled during the study period (21). The objective of the present study was to

2 J. Food Prot., Vol. 76, No. 6 RECALLS OF FOODS DUE TO MICROBIOLOGICAL CONTAMINATION 933 determine whether the role of microbial contamination in foods under the jurisdiction of the FDA for fiscal years 2003 through 2011 changed appreciably since the mid-1990s (21), and to characterize the foods recalled and the pathogens involved in such recalls. MATERIALS AND METHODS As stated in the Code of Federal Regulations, a recall means a firm s removal or correction of a marketed product that FDA considers to be in violation of the laws it administers and against which the agency would initiate legal action, e.g., seizure (1). The procedures used by FDA-regulated firms to conduct recalls of violative foods (with the exception of infant formulas that pose a risk to human health) are described in Title 21, Part 7 of the Code of Federal Regulations; a description of procedures employed for conducting recalls of infant formula that pose a risk to human health is contained in Title 21, Part 107 of the Code of Federal Regulations (1). A recall event can involve the recall of one or more products of one or more different kinds of foods (designated by industry codes). The FDA maintains a record of information pertinent to recalled products in the database Mission Accomplishment and Regulatory Compliance Services (MARCS) Recalls. For the present project, we reviewed all records in this database pertaining to foods recalled as a result of microbiological contamination from 1 October 2002 through 30 September 2011 (i.e., fiscal years 2003 through 2011). A recalled product was defined as microbiologically contaminated if (i) laboratory analysis of the product revealed the presence of one or more organisms recognized as being foodborne pathogens (e.g., Listeria, Salmonella, Escherichia coli, Cronobacter sakazakii [previously called Enterobacter sakazakii], Bacillus cereus, S. aureus, norovirus), (ii) laboratory analysis of the product detected the presence of a toxin of bacterial origin capable of causing human illness (e.g., C. botulinum toxin, S. aureus enterotoxin, or B. cereus toxin), and/or (iii) an epidemiologic association was established between ingestion of a product and human illness of a microbiologic nature. In addition, we considered foods to be microbiologically contaminated if they had been produced, transported, labeled, or stored under conditions that could have facilitated the production of C. botulinum toxin, irrespective of whether laboratory analysis had or had not been conducted to test for the presence of the toxin (e.g., uneviscerated fish, certain under-processed foods, foods contaminated postprocessing). Finally, we considered products to be potentially contaminated with pathogens if they met any of the following conditions: molluscan shellfish harvested from waters closed to harvesting by state or international authorities, juices not pasteurized or manufactured under requirements of a hazard analysis and critical control point system (HACCP), cheeses produced from unpasteurized milk aged for less than the minimum required period (60 days), or any food manufactured in a manner whereby it could have become contaminated with pathogens (e.g., pickled eggs produced without monitoring and recording ph values). We excluded recalls of foods contaminated with deoxynivalenol because our interest was pathogenic agents and/ or their toxins. We also excluded recalls of foods contaminated with yeast, mold, and/or spoilage organisms, because our focus was on agents with a well-established record of causing human infections or intoxications acquired from food. For each food product recalled, the FDA assigns a recall classification number (I, II, or III) that categorizes the degree of health hazard presented by the product (1). A Class I recall involves a situation in which there is reasonable probability that the use of or exposure to a violative (recalled) product will cause TABLE 1. Number of food recall events and products recalled for microbiological contamination by year, fiscal years 2003 through 2011, by the U.S. Food and Drug Administration Year No. of events Recalls No. of products , , Total 1,395 5,164 serious adverse health consequences or death. Class II recall involves a situation in which the use of or exposure to a violative (recalled) product could cause temporary or medically reversible adverse health consequences or where the probability of serious adverse health consequences is remote. Class III recall involves a situation in which the use of or exposure to a violative (recalled) product is not likely to cause adverse health consequences (1). The assessment of hazard posed by each recalled food product is conducted by an ad hoc group of scientists within the FDA s Center for Food Safety and Applied Nutrition. Factors taken into consideration include the occurrence of any disease or injuries that might have occurred after exposure to the product, the population segments most likely to be exposed to the product and the degree of seriousness of the health hazard to which they would be exposed, the likelihood of occurrence of the hazard, and the consequences of occurrence of the hazard (1). For each food product recalled due to microbiological contamination during the study period, we reviewed the recall record to determine the following information: pathogen or toxin responsible for contamination, recall classification (I, II, or III), and product type (e.g., dairy, seafood, produce). In addition, we determined whether any illnesses or injuries had been reported to FDA after exposure to the products, using reports submitted by consumers, producers, local and state public health departments, and the Centers for Disease Control and Prevention. We computed frequency counts for pathogens and toxins, product types, and recall classifications. With regard to product type, we used the same categories as those reported by Wong et al. (21) in their study of foods and cosmetics recalled in the United States due to microbiological contamination for fiscal years 1994 through 1998; although, we added two new categories, namely, nuts and edible seeds and spices. For the purpose of categorizing product types, we used FDA-designated two-digit industry codes ( gov/food/guidancecomplianceregulatoryinformation/priornotice ofimportedfoods/ucm htm). RESULTS For the study period 1 October 2002 through 30 September 2011 (i.e., fiscal years 2003 through 2011), the FDA s Center for Food Safety and Applied Nutrition classified a total of 3,360 food recall events. Of these, 1,395 (42%) recall events (involving a total of 5,164 products) resulted from microbiological contamination (Table 1).

3 934 DEY ET AL. J. Food Prot., Vol. 76, No. 6 TABLE 2. Number and classification of food-related recall events and products recalled for microbiological contamination, by pathogen, toxin, or condition, fiscal years 2003 through 2011, by the U.S. Food and Drug Administration No. of events Pathogen, toxin, or condition Total Classification I II III No. of products recalled Salmonella ,792 Listeria monocytogenes a 868 Clostridium botulinum Escherichia coli O157:H7 19 b Non-O157:H7 c Staphylococcus aureus Enterobacter sakazakii 2 d Shigella Burkholderia cepacia Klebsiella pneumoniae Paecilomyces variotii Bacillus spp Pseudomonas spp Juice HACCP insufficiencies Hepatitis A virus Cheese made from raw milk aged,60 days Manufactured in manner whereby it could become contaminated with pathogens Shellfish obtained from closed harvest waters Multiple pathogens e Total 1,395 1, ,164 a, no data. b 2003, one recall involving epidemiologic association to outbreak pathogen not recovered from implicated food; 2005, one recall involving pathogen recovered from spent irrigation water used in conjunction with alfalfa sprouts; 2006, one recall involving chopped romaine lettuce associated with outbreak; 2007, six recalls involving spinach (outbreak strain of pathogen recovered from an opened bag of spinach obtained from an ill consumer). c Escherichia coli. d One event involved powdered infant formula (Class I) and two adult nutritional products (Class II). e Recalls involving more than one pathogen (e.g., Listeria monocytogenes and E. coli O157:H7, 1 recall; L. monocytogenes and Staphylococcus aureus, 3 recalls; S. aureus and E. coli [non-o157:h7], 1 recall). The presence of bacterial pathogens accounted for the greatest number of recall events due to microbiological contamination. Among the 1,395 food-related recall events, 996 (71%) involved contamination with Salmonella spp., and 248 (18%) involved contamination with Listeria monocytogenes (Table 2). For 92 (7%) events, the processing, transport, labeling, and/or storage of products were determined to be conducive to the production of C. botulinum toxin. In two of these events, laboratory evidence indicated the presence of C. botulinum toxin (canned hot dog chili sauce) or spores (swollen cans of green beans), while in 26 other events, conditions were deemed to be sufficiently conducive to the production of toxin to merit a Class I recall classification. Although processing, transport, labeling, and/or storage conditions were conducive to the potential for C. botulinum contamination in the remaining 64 events, a reduced likelihood of toxin production was deemed to merit a Class II or III classification. A wide variety of products were recalled for microbiological contamination (Table 3). The product categories with the greatest number of recall events were nuts and seeds, fishery seafood products, and spices. Table 4 presents the types of food products recalled as a result of contamination with five leading pathogens. In general, contamination with Salmonella was responsible for recalls of a wider variety of foods than L. monocytogenes, S. aureus, or E. coli O157:H7. Fishery seafood products were the leading product type recalled for both L. monocytogenes and C. botulinum related events. With regard to recall classification, 90% of recall events related to food products were Class I recalls (Table 2). There were 31 reported outbreaks of foodborne disease in the United States associated with foods recalled for microbiological contamination during the study period (Table 5). To our knowledge, for all 31 outbreaks, the food vehicle responsible for causing disease was identified after initial illnesses were reported. The majority of outbreaks were associated with produce items, and in 20 outbreaks, Salmonella was responsible for causing illness. A total of 1,802 products were recalled in conjunction with the 31 reported outbreaks.

4 J. Food Prot., Vol. 76, No. 6 RECALLS OF FOODS DUE TO MICROBIOLOGICAL CONTAMINATION 935 TABLE 3. Recalls of food products, by product type, resulting from microbiological contamination, fiscal years 2003 through 2011, per U.S. Food and Drug Administration Product type Industry code No. of recall events No. of products recalled Whole grains Bakery goods Macaroni, noodle products Cereals, breakfast foods Snack food items Milk, cream Cheese, cheese products Ice cream Filled milk, imitation milk Eggs, egg products Fishery, seafood products Poultry products, exotic meat Meat-like vegetable protein products Fruits, fruit products Pit fruits, fruit products Vine fruit, fruit products Nuts and edible seeds Vegetables, vegetable products Vegetables, vegetable products (tuber, root) Vegetable oil Dressings and condiments Spices Soft drinks and water Beverage bases Coffee and tea Candy without chocolate Chocolate and cocoa products Gelatin and pudding mixes Food sweeteners Multiple foods, side dishes Soups Prepared salad products Baby food Meal replacements Food additives Food additives Dietary supplements Multiple product codes a 192 1,394 Total 1,395 5,164 a, no data. DISCUSSION Reviews of recalls of food products contaminated with microbiological pathogens can supplement information gained from ongoing surveillance systems for foodborne disease by conveying the nature of microbiological exposures consumers face from foods marketed in interstate commerce. In the present study, we showed that a variety of foods can become contaminated with diverse pathogens, resulting, on average, in some 155 recalls each year of food products regulated by the FDA. The presence of Salmonella and L. monocytogenes accounted for the greatest number of foods recalled for microbial contamination, collectively responsible for approximately 90% of recalls. While the proportion of recalls of microbiologically contaminated food products due to L. monocytogenes declined from 61% (813 of 1,328 products) for fiscal years 1994 through 1998 (21) to 18% (868 of 5,164 products) for fiscal years 2003 through 2011, the proportion of food products recalled due to Salmonella contamination increased from 11% (143 of 1,328 products) for the earlier period to 73% (3,792 of 5,164 products) more recently. The decline in the proportion due to L. monocytogenes coincided with a reduction in the incidence of listeriosis in the United States from approximately seven to three cases per million population from 1986 to 2010 (10, 13). The decline in the proportion of recalled products due to L. monocytogenes contamination could reflect a concerted effort by industry to reduce the presence of the organism in the food manufacturing, processing, and distribution arenas. However, an outbreak of listeriosis in 2011 linked to the consumption of cantaloupes, a vehicle that had not been previously recognized as a cause of infection with L. monocytogenes, serves as a stark reminder of the potential for this pathogen to reemerge as a cause of major outbreaks (11). Salmonellae played a prominent role in foods recalled for microbial contamination during the present study, accounting for almost three-quarters of recall events. In several instances, contamination of a single ingredient subsequently incorporated into a vast array of products distributed through multiple channels required expansive recalls. For example, in the setting of a national outbreak of salmonellosis during 2008 through 2009 linked to the consumption of peanut butter contaminated with Salmonella Typhimurium (8), 1,553 peanut butter containing products were recalled, accounting for 40% of all recalls of food products due to Salmonella contamination during the study period. In another instance, Salmonella Tennessee contamination of hydrolyzed vegetable protein, a common ingredient often used as a flavor enhancer in many processed foods, led to a total of 86 recalls of 534 products during fiscal years 2010 through Consistent with its leading rank among causes of bacterial foodborne disease in the United States, salmonellae were responsible for 97% (1,851 of 1,915) of the products recalled (during the study period associated with reported human infections) (Table 5). Notably, 65% of Salmonella-related recall events associated with reported illnesses involved fruits or vegetables, a category of foods increasingly recognized as a source of foodborne disease (17). However, an outbreak of E. coli O157:H7 infections associated with contaminated spinach in 2006 (5) underscores the fact that produce harboring pathogens other than salmonellae can extract a heavy toll in human illness. The number and variety of foods recalled as a result of microbiological contamination call to attention again the potential for pathogens to be present in a wide diversity of products. The list of recalled foods (Table 3) highlights the fact that both raw and processed foods can, under certain circumstances, become contaminated, most often with bacterial or viral pathogens. At least three outbreaks of

5 936 DEY ET AL. J. Food Prot., Vol. 76, No. 6 TABLE 4. Number of food-related recall events by industry and pathogen, fiscal years 2003 through 2011, by the U.S. Food and Drug Administration No. of recall events by pathogen Industry Listeria monocytogenes Salmonella Clostridium botulinum Staphylococcus aureus Escherichia coli O157:H7 Whole grains a 3 Bakery goods Macaroni and noodle products 2 3 Cereals, breakfast foods 13 Snack food items 97 Milk, cream 2 24 Cheese, cheese products Ice cream Filled milk, imitation milk products 1 Egg, egg products 3 20 Fishery, seafood products Poultry products, exotic meats 1 1 Meat-like vegetable protein products Fruits, fruit products Pit fruits, fruit products Vine fruits, fruit products 2 31 Nuts and edible seeds Vegetable, vegetable products Vegetable, vegetable products (roots, fungi, tuber) Vegetable oil 1 Dressings and condiments 7 2 Spices Soft drinks and water 1 Beverage bases 3 2 Coffee and tea 13 Candy without chocolate 11 Chocolate and cocoa products 45 1 Food sweeteners 1 Multiple foods, side dishes, dinner Soups 7 1 Prepared salad products Baby food 1 Meal replacements 1 7 Food additives 4 Dietary supplements 8 Multiple codes 6 69 Total a, no data. illness associated with food products recalled during the study period exemplify the challenges faced when infectious agents gain entry to foods. In the first, an outbreak of Salmonella Tennessee infections associated with the consumption of contaminated peanut butter, illnesses occurred for months prior to the time peanut butter manufactured by a single firm was identified as the vehicle of infection (6). In the second, during an outbreak of Salmonella Wandsworth infections in the United States in 2007, illnesses occurred at a disproportionately high rate among toddlers, an age group that commonly partook in eating a processed snack food from which the outbreak strain of Salmonella Wandsworth was eventually recovered (18); an investigation into the manufacture of this product suggested that a contaminated vegetable powder used as a seasoning flavoring agent had been sprayed onto the snack food after the baking process, thereby avoiding a kill step. The third outbreak, one involving E. coli O157:H7 infections and ready-to-bake cookie dough (15), demonstrated that human behavior namely, the deliberate consumption of a product intended to be baked before ingestion can play a significant role in terms of routes of transmission of foodborne pathogens. All three outbreaks underscore the continuing need to apply strict controls to the production of foods of all types and to maintain vigorous disease surveillance systems to ensure that any contaminated products that do reach the marketplace can be removed as expeditiously as possible. ACKNOWLEDGMENT The authors thank Elizabeth Hogan for her assistance with locating recall records.

6 J. Food Prot., Vol. 76, No. 6 RECALLS OF FOODS DUE TO MICROBIOLOGICAL CONTAMINATION 937 TABLE 5. Reported foodborne outbreaks associated with U.S. Food and Drug Administration regulated food products recalled for microbiological contamination, fiscal years 2003 through 2011 Microbe or toxin Product recalled No. of products recalled Year(s) of outbreak Reference Escherichia coli O157:H7 Lettuce Salmonella Saintpaul Alfalfa sprouts Salmonella Alfalfa sprouts Salmonella Alfalfa sprouts Salmonella Egg whites Salmonella Enteritidis Raw almonds Salmonella Bovismorbificans Alfalfa sprouts Salmonella Typhimurium Ice cream Hepatitis A Green onions E. coli O157:H7 Salad Salmonella Typhimurium Orange juice E. coli O157:H7 Spinach Salmonella Tennessee Peanut butter Salmonella Wandsworth Mixed vegetables Shigella sonnei Carrots Clostridium botulinum Hot dog chili sauce Salmonella Litchfield Cantaloupes Salmonella Saintpaul Jalapeno peppers Salmonella Typhimurium Alfalfa sprouts Salmonella Saintpaul Sprouts E. coli O157:H7 Cookie dough Salmonella Typhimurium Peanut butter, peanut 1, butter containing products Salmonella Montevideo Black pepper Salmonella Alfalfa sprouts Salmonella Typhi Frozen mamey pulp Salmonella Enteritidis Shell eggs E. coli O157:H7 Romaine lettuce E. coli O145 Romaine lettuce Staphylococcus aureus Bakery product Listeria monocytogenes Cantaloupes Salmonella Agona Papayas REFERENCES 1. Anonymous Enforcement policy. Federal Food, Drug, and Cosmetic Act. Code of Federal Regulations, no. 21. U.S. Government Printing Office, Washington, DC. 2. Barton Behravesh, C., R. K. Mody, J. Jungk, L. Gaul, J. T. Redd, S. Chen, S. Cosgrove, E. Hedican, D. Sweat, L. Chávez-Hauser, S. L. Snow, H. Hanson, T. A. Nguyen, S. V. Sodha, A. L. Boore, E. Russo, M. Mikoloit, L. Theobald, P. Gerner-Smidt, R. M. Hoekstra, F. J. Angulo, D. L. Swerdlow, R. V. Tauxe, P. M. Griffin, I. T. Williams, and the Salmonella Saintpaul Outbreak Investigation Team outbreak of Salmonella Saintpaul infections associated with raw produce. N. Engl. J. Med. 364: Centers for Disease Control and Prevention Surveillance for foodborne disease outbreaks United States Morb. Mortal. Wkly. Rep. (49)SS-1: Centers for Disease Control and Prevention Outbreak of Salmonella serotype Enteritidis infections associated with raw almonds United States and Canada, Morb. Mortal. Wkly. Rep. 53: Centers for Disease Control and Prevention Ongoing multistate outbreak of Escherichia coli serotype O157:H7 infections associated with consumption of fresh spinach United States, September Morb. Mortal. Wkly. Rep. 55: Centers for Disease Control and Prevention Multistate outbreak of Salmonella serotype Tennessee infections associated with peanut butter United States, Morb. Mortal. Wkly. Rep. 56: Centers for Disease Control and Prevention Botulism associated with commercially canned chili sauce Texas and Indiana, July Morb. Mortal. Wkly. Rep. 56: Centers for Disease Control and Prevention Multistate outbreak of Salmonella infections associated with peanut butter and peanut butter containing products United States, Morb. Mortal. Wkly. Rep. 58: Centers for Disease Control and Prevention Salmonella Montevideo infections associated with salami products made with contaminated imported black and red pepper United States, July 2009 April Morb. Mortal. Wkly. Rep. 59: Centers for Disease Control and Prevention Vital signs: incidence and trends of infection with pathogens transmitted commonly through food Foodborne Diseases Active Surveillance Network, 10 U.S. sites, Morb. Mortal. Wkly. Rep. 60: Centers for Disease Control and Prevention Multistate outbreak of listeriosis associated with Jensen Farms cantaloupe United States, August September Morb. Mortal. Wkly. Rep. 60: Jain, S., S. A. Bidol, J. L. Austin, E. Berl, F. Elson, M. L e- Williams, M. Deasy III, M. E. Mall, V. Rea, J. D. Vojdani, P. A. Yu, R. M. Hoekstra, C. R. Braden, and M. F. Lynch Multistate outbreak of Salmonella Typhimurium and Saintpaul infections associated with unpasteurized orange juice United States, Clin. Infect. Dis. 48: Klontz, K. C., P. V. McCarthy, A. R. Datta, J. O. Lee, D. W. K. Acheson, and R. E. Brackett Role of the U.S. Food and Drug

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