SECTION 2
Food Safety Issues

Safety of Direct Food Additives in the U.S.

Indirect Food Additives

Food Preparation

"Naturally Occurring" Food Constituents

Contamination

SECTION 3
Mitigation Strategies

Risk Assessment

Identification of High Risk Populations

Prudent Uses of Antibiotics in Animal Agriculture

Consumers' Responsibilities

The Pharmacists' Role in Educating the Public

When Mitigation Strategies Fail

SECTION 4
Therapy for Foodborne Illnesses

Signs and Symptoms of Exposure to Foodborne Pathogens

Therapeutic Approaches

Supportive Measures

SECTION 5
Summary

REFERENCES

Food Safety and Foodborne Illnesses: Opportunities for the Pharmacy Professional
to Educate the Consumer

David C. Kossor, RPh, PhD, DABT
Dr. Kossor is Manager, Product Development
Roche Vitamins Inc. in Nutley, NJ.

Temple University School of Pharmacy is approved by the American Council on Pharmaceutical Education (ACPE) as a provider of continuing education. Its CE programs are developed in accordance with the "Criteria for Quality and Interpretive Guidelines" of ACPE. Acceptable for 2.0 hours of Continuing Education Credits (0.2 CEU) through October 1, 2002.  ACPE 057-999-99-080-H04.

Today, one can hardly open a newspaper or watch the evening news broadcast without hearing that our food supply is being threatened by some new chemical or pathogen. Within the past few years, consumers increasingly have demanded a safe and wholesome food supply. This cause has been championed over recent months by educators, legislators, and the media. Unfortunately, in most instances, the overwhelming guidance for consumers on food safety has come from the media, whose reports can be inconsistent. More often their purpose is not to educate, but to maintain the attention of the audience by focusing on emotional and/or sensational aspects of a particular issue. Consequently, the facts are rarely presented in a comprehensive and balanced fashion, making it difficult for consumers to make critical decisions about their foods. The result, typically, is a lack of consumer confidence in particular foodstuffs and in those who provide and/or handle foodstuffs. Clearly, consumers need a professional whom they can turn to for reliable and expedient information and to facilitate informed decisions. Not unexpectedly, many consumers seek the advice of their pharmacist on food safety issues. Indeed, numerous surveys over many years have indicated that consumers continue to regard the pharmacist as one of the most trusted members of the health care team, and consumers are recognizing that wholesome food is important for the maintenance of optimum health. The pharmacist also has the needed training and expertise to understand the science behind the issues, and is ideally positioned in the community and readily accessible to consumers to educate them about the important points that often do not appear in the media reports. 

One of the most rapidly expanding sectors of retail pharmacy practice today is the pharmacy department in many grocery stores and supermarkets—a perfect niche in which to provide this critically important service. This program focuses on the many factors that can jeopardize the safety of our food, and how the pharmacist can educate and motivate consumers to take an active role in maintaining a safe food supply.

Federal Regulatory Responsibilities

It is appropriate first to consider the regulatory agencies in the United States that are responsible for assuring the safety of foods. 

Pharmacists are familiar with the important role played by the FDA in assuring the safety and efficacy of drugs and biologicals. These functions are provided by the FDA’s Center for Drug Evaluation and Research (CDER) and Center for Biologicals’ Evaluation and Research, respectively. The FDA also participates in food safety assurance through their Center for Food Safety and Applied Nutrition (CFSAN) and the Center for Veterinary Medicine (CVM). CFSAN is responsible for assessing the safety of direct food additives, while CVM is responsible for the approval of compounds used to treat food-producing animals that might produce residues in edible tissues. 

In addition to the FDA, there are numerous federal agencies that share the responsibility of assuring food safety.¹ The other principal agency responsible for food safety is the U.S. Department of Agriculture which oversees food processing facilities. A branch of the USDA, the Food Safety and Inspection Service (FSIS), is responsible for inspecting the quality of livestock and poultry and assessing the presence of potential contaminants. Principally this is conducted at slaughterhouses, meat packaging facilities, and retail food stores. Also within the USDA is the Animal and Plant Health Inspection Service (APHIS), whose mission is to ensure the health and care of animals and plants, and to improve agricultural productivity and competitiveness. To accomplish these objectives, APHIS monitors international travelers to minimize entry of foreign pests and diseases, and assesses the safety of agricultural products, veterinary biologicals, and genetically engineered plants. 

In addition to the USDA and the FDA, the Environmental Protection Agency (EPA) plays a role in assessing the safety of pesticides and environmental contaminants that may enter the food supply. For example, in August 1996, Congress enacted the Food Quality Protection Act (FQPA), which amended the Federal Insecticide, Fungicide, and Rodenticide Act.² The purpose of FQPA is to protect children from environmental toxins. Consequently, the EPA was required to assure that its methods for the testing of human health effects reflects these new standards for the safety of children. Finally, the Centers for Disease Control and Prevention (CDC) has important roles in monitoring outbreaks of foodborne illnesses and implementing mitigation strategies. Unlike the previous federal agencies that are regulatory in nature, the CDC is responsible for the surveillance and mitigation of potential health threats. Together, these agencies provide an integrated approach to evaluating all aspects of food processing to assure that food quality is not compromised. Throughout the Clinton administration, a focus has been maintained on the availability of a safe food supply. For example, in 1997, President Clinton announced a new initiative to improve the safety of the nation’s food supply. The Food Safety Initiative (FSI) brings together the collective expertise of the FDA, CDC, USDA, and EPA to identify major food safety concerns and to implement short- and long-term corrective measures.^3,4  

One particularly effective program implemented in 1998 in response to the FSI by the USDA-FSIS is the Hazard Assessment and Critical Control Points (HACCP) program, aimed at controlling potential contamination of animal carcasses in slaughterhouses.⁵ This so-called “megareg” (ie, the document contains more than 1,000 pages) is a comprehensive strategy that requires slaughterhouse facilities to outline the process by which the animals traverse the facility, identify key points where contamination is likely to occur, and implement corrective actions. At this time, the future of FSI is unclear. In 1998, President Clinton established the President’s Council on Food Safety to develop a comprehensive strategic plan for federal food safety activities. Many speculate that this action ultimately may lead to the creation of a single food safety agency within the federal government. Finally, state and local governments throughout the United States play a role. The food safety goal is maintained by the cooperative efforts of state and local health departments.

Foodborne illness is a general term that describes illnesses arising from the ingestion of certain food constituents. Foodborne illness in the United States typically is caused by the ingestion of microbial contaminants. Alternatively, illness can result from a food additive (either direct or indirect), a nonmicrobial contaminant, or “natural” food constituents.

Over the past decade, there has been exponential growth in the demand for processed foods in the United States. In response, substantial research programs have been instituted to develop new food additives. These include, but are not limited to, colorants, flavorants, preservatives, sweeteners, stabilizers, emulsifiers, fortifiers, digestion enhancers, and fat substitutes.⁶ Many of the compounds currently in use had been introduced many years ago. These compounds are classified as “generally regarded as safe,” or GRAS, and have safety profiles that have been established by numerous epidemiologic studies over the years.1 GRAS compounds are regulated under the 1958 amendment to the Federal Food, Drug, and Cosmetic Act. In contrast, approval for a new compound to be used as a food additive is dependent upon acceptable performance in rigorous toxicology tests. The FDA acknowledges that the absolute safety of food additives cannot be determined experimentally. Therefore, the goal of the FDA is to assure a “reasonable certainty of no harm.” To accomplish this standard, the FDA requires a battery of standardized tests to be performed, which generally include genetic toxicology (bacterial and mammalian cell mutagenesis assays), reproductive toxicology (pre-, peri-, and post-natal exposure), acute and chronic toxicity studies, carcinogenicity bioassays, and most recently, immunotoxicology assessments. Toxicology tests that are required by the FDA and the manner in which they are to be conducted have been outlined in a publication entitled The Toxicological Principles for the Safety Assessment of Direct Food Additives and Color Additives Used in Food, known as the “redbook.”⁷ For these toxicology studies, multiple dosage levels of the investigational additive are given to surrogate laboratory species (usually the rat and the dog), and the highest dosage level that produces no adverse effects is identified. This dosage level, termed the “no observed adverse effect level,” or NOAEL, is used to determine a safe level to which humans may be exposed. To accomplish this, appropriate safety factors are used to account for uncertainties when extrapolating the response of the surrogate species to what might be the expected response in humans, and to consider the types of foods that might contain the additive and the expected levels of consumption for these foods. These safety factors are applied to the NOAEL, which results in the determination of the “acceptable daily intake” (ADI) for a particular compound. 

The ADI is the highest concentration of a particular additive that is permitted to be used in a particular food.⁶ For example, safety studies for the sweetener aspartame have demonstrated a NOAEL of 2 to 4 g/kg in laboratory animals, from which an ADI of 50 mg/kg has been established for human consumption.⁸  

Over the past decade, there has been enormous growth in biotechnology, resulting in a growing number of plants that have been modified genetically to enhance growth, yields, and stability of produce in the supermarket. In the United States, this growth in biotechnology has resulted largely due to increased consumer support and confidence in the safety of these genetically altered products. Indeed, the biotechnology industry has succeeded by harnessing many of the selection processes that are present in nature and by applying pressure for the desirable traits to be expressed in the products. The increasing of yields will assure the availability of an abundant and affordable food supply. 

On the other hand, the industry is well aware of the importance of maintaining consumer confidence in their products. Accordingly, modified foods are subjected to the same rigorous toxicology testing programs as other food additives to ensure their safety for human consumption.⁹ In Europe, however, the situation is much more tentative, and the public has not accepted genetically modified foods. At this time, it appears that it will be some time before Europeans will incorporate these products into their diets. The above discussion pertains to compounds that are directly and intentionally added to foods. However, a potentially greater problem exists with compounds that are indirectly added to foods. These are problematic because they are used in the processing and/or packaging of foods, and the extent to which they enter the food in many instances is difficult to determine and regulate. Thus, additional safety factors must be applied to determine a safe level of a particular indirect food additive.

One class of compounds that poses a substantial health concern as an indirect food additive is pesticides. These compounds comprise a group of structurally diverse molecules that present potential adverse human health consequences following acute exposure, such as chloracne/dermatitis (eg, phenoxyacetic acid derivatives), estrogenic effects (eg, DDT, methoxychlor), cholinesterase inhibition (eg, organophosphates), and respiratory distress (eg, paraquat).

 Accordingly, the EPA has established rigorous guidelines for the use of pesticides in food production, and monitors the food supply for the presence of pesticide residues to assure that they are not present in quantities which pose an imminent health threat. In fact, there are incidents that have occurred to suggest that regulatory restrictions occasionally may be too rigorous and/or premature. 

For example, since the 1960s, the compound daminozide had been used as a plant growth regulator for apples, under the trade name Alar. In 1988, data from preliminary in vitro studies suggested that Alar was a suspected human carcinogen,¹⁰ which prompted the EPA to restrict consumption of apples treated with the compound. However, data from subsequent studies performed in vivo did not support the previous in vitro claims,¹¹ but this did little to reclaim the enormous financial losses that were incurred by apple growers in Washington State, as a result of the loss of consumer confidence in apples. 

The Alar incident underscores the substantial and far-reaching economic effects that are produced by regulatory decisions and the adverse consequences of enacting precautionary principles based on preliminary data.^12,13 Thus, pivotal decisions of this type should be made only after careful review of all relevant data (including post-marketing surveillance) and input from all stakeholders.

Veterinary therapeutics also may be viewed as potential sources of indirect food additives, which may be present as residues in edible tissues following treatment of food-producing animals. In the United States, current livestock and poultry production facilities are operated on a very large scale, and typical herds might include hundreds of head of cattle or swine and poultry houses that might hold several thousand birds at one time. To maintain these types of extensive farming operations, the animals typically are medicated to treat disease, prevent disease, and promote growth and optimum health. To accomplish these end points, the animals are treated with antimicrobials and, under certain circumstances, hormones such as somatotrophins. Consequently, there is a concern that residues of these medications might be retained in the edible tissues of the animal and pose a potential health threat upon ingestion. This situation is managed at two levels. Initially, all compounds used to treat food-producing animals must be approved by the FDA’s Center for Veterinary Medicine (biologicals are regulated by USDA-APHIS). Approval is contingent upon the establishment of an ADI, based on the results of a toxicology testing program, similar to that described previously for CFSAN. To assure that the residues present in edible tissues are below those established by the ADI, a withdrawal time is established. This is the period of time prior to slaughter when the drug cannot be administered. Essentially, this provides a “washout” period for the concentration of a particular drug in edible tissues to decrease to acceptable levels as defined by the ADI. Drug residue levels in foods of animal origin are monitored by FDA-CVM and USDA-FSIS to assure that residues do not exceed permissible levels. 

The results of a 5-year survey (1992–1996) indicated that violative residues occasionally are observed, predominantly in culled dairy cows and bob veal calves.¹⁴ Generally, the incidence of violative drug residues detected in foods is very low.¹⁵ Foods also can acquire indirect additives through handling. It has long been recognized that components present in packaging materials can be leached out and enter the foods. For example, phthalate esters had been used as plasticizers in plastic packaging material, and it was found that certain foods caused the phthalates to be leached out of the packaging and enter the foods. 

Since the phthalates were shown to induce peroxisome proliferation and hepatocarcinomas in rodents, their usage in food packaging materials has been replaced by newer and safer materials. Some foods are packaged in brown glass bottles to reduce the transmission of light and, hence, photodecomposition. However, the glass is made brown by the incorporation of iron compounds, and for some products, the iron-catalyzed oxidation of labile constituents has been demonstrated. Therefore, it is important to use appropriate packaging materials that are approved for contact with specific foods.

Cooking also can introduce indirect additives to food prior to consumption that might pose an adverse human health risk. For example, recent data have demonstrated that cooking promotes the oxidation of lipids and sterols in foods, and increased lipid oxides have been associated with the pathogenesis of coronary artery disease and other degenerative processes.¹⁶ In addition, it has been well documented that cooking promotes the reaction of nitrite preservatives with secondary amines present in the food, resulting in the formation of nitrosamines. Nitrites are metabolites of nitrate preservatives that are added to meats to prevent heme degradation that otherwise would discolor the meat. Cooking also induces the formation of heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) by the thermal decomposition of proteins present in the food (also known as protein pyrolysates).¹ Many of these compounds are potent mutagens and have been shown to be carcinogenic in rodent bioassays.¹⁷ Perhaps, it is prudent for consumers to limit their consumption of meats containing nitrate preservatives and to avoid consuming charcoal-broiled or fried meats that promote HCA/PAH formation. 

More recently, concerns have been raised about the safety of microwave cooking. Our society increasingly has become dependent on the convenience and expediency of microwave cooking. However, microwave cooking also has its shortcomings. One issue of concern is the potential for microwaves to alter the chemical structure of food components. Microwaves are relatively low-frequency radio waves that produce heat in foods by causing the covalent bonds in water molecules to resonate.¹⁸ Although the microwave energy is insufficient to cleave the bonds in the water molecules, the effect of microwave irradiation on other molecular structures has not been studied extensively. Indeed, it is well known that microwave energy induces metal oxidation. 

In response to concerns about microwave safety, there are considerable research efforts currently under way to evaluate the effects of microwave cooking on foods.¹⁹ Current data suggest microwaves do not produce any changes in our foods that are not also associated with other conventional means of cooking. Another important safety issue posed by microwave cooking is the extent to which the food is cooked. Many foods intended for microwave cooking are frozen, and frequently frozen foods prepared by microwave cooking do not attain the proper internal temperature to ensure that potential microbial contaminants are killed.²⁰

Direct and indirect food additives complement the millions of compounds that are “naturally” present in food. Although food additives are subjected to rigorous safety testing programs, the majority of natural compounds present in foods have not been identified, let alone characterized with respect to their potential pharmacodynamic effects.

 Conversely, compared with synthetic materials, most consumers consider “natural” products to be a safer alternative. An explanation for this apparent contradiction continues to elude toxicologists. Nonetheless, there are numerous classes of natural products that are known to induce adverse human health consequences, and consumers need to be aware of these potential risks. Among these are natural colorants, flavors, and spices. For example, it has been reported that a cup of coffee contains over 1,000 chemicals but only about 28 of these compounds have been characterized, 19 of which are rodent carcinogens.²¹  

In addition, recent evidence suggests that plants contain phytoestrogens that have been shown to mimic the effects of estrogen upon ingestion.^22,23 Moreover, there are numerous natural toxins produced by plants (eg, muscarine, belladonna alkaloids, xanthines, etc) that are well known to pharmacists, and occasionally an individual will seek medical attention as a result of accidental poisoning. For example, in 1990 there were more than 100 cases of food poisoning treated in hospital emergency rooms that were due to the consumption of wild mushrooms. In recent years, this figure likely has increased due to the increasing popularity of “natural” and/or exotic foods.²⁴ Symptoms of mushroom poisoning typically include cholinergic symptoms, due to the presence of alkaloids such as muscarine, which is produced by Amanita muscaria. However, the delayed type of mushroom poisoning that occurs following ingestion of Amanita phalloides is particularly problematic, because of the presence of the toxin phalloidin, which inhibits the enzyme RNA synthase and results in hepatotoxicity. Immediate symptomatic treatment is essential as the toxin produces irreversible hepatic damage. Ingestion of A phalloides is fatal in 50% to 80% of cases and the limited therapeutic options include orthotopic liver transplantation.²⁵  

Natural toxins also are common among many species of fish and shellfish. The intoxication resulting from the ingestion of certain fish has been named ichthyosarcotoxism, and examples include the puffer fish (tetrodotoxin), snapper (ciguatera toxin), and shark (elasmobranch toxin). Intoxication also can occur following consumption of mussels (paralytic shellfish poison). The substantial increase in seafood consumption over recent years likely will contribute to the greater percentage of foodborne illnesses caused by these toxins. In response to the increased demand for seafood, there has been substantial growth in aquaculture, or fish farming. Although seafood produced in this manner theoretically should have lower levels of toxins compared with species grown in the wild, there are additional concerns that microbial growth may be promoted by high-density production facilities. Thus, microbial contamination in aquaculture, as in other intensive farming operations, must be monitored and maintained below an acceptable threshold level.

The majority of food poisonings are caused by the ingestion of foods that have become contaminated. Typically, foods become contaminated by improper handling or by exposure to contaminated surfaces. The most common foodborne contaminants are bacteria. Perhaps the most well-known source of foodborne bacterial contamination is botulism, which is caused by overgrowth of the bacterium Clostridium botulinum. This bacterium is classified as an obligate anaerobe, and optimum growth occurs in the absence of oxygen. C botulinum poisonings have become rare because of advances in technology in the canning industry. Alternatively, botulism following consumption of home-canned foods is observed more frequently. Therefore it is important that consumers know and follow correct canning procedures, which include maintaining the temperature of the food at a minimum of 120 degrees C for a period of at least 30 minutes to kill spores that may be present. It is also essential that the final product is properly vacuum-sealed to exclude airborne microbes. Symptoms of botulism occur between 12 and 48 hours after consumption of contaminated foods, which include blurred vision, diplopia, dysphonia, dysphagia, and dyspnea, followed by generalized weakness, nausea, vomiting, and abdominal cramps.²⁶ The symptoms are produced by C botulinum exotoxin, which is among the most potent neurotoxins that have been discovered to date. Indeed, the acute dose that produces lethality in 50% of exposed animals (LD50) is 0.00001 mg/kg, or less than 1 microgram for an average adult.¹ Thus, individuals that are suspected of consuming foods contaminated with C botulinum should seek immediate medical attention. Botulinum antitoxins have been developed and have been shown to be effective in the treatment of botulism. 

Foods of animal origin also can become contaminated by zoonotic bacteria, which can be transferred to the carcass during processing at the slaughterhouse. Although most species of zoonotic bacteria have specific animal hosts and, thus, do not colonize the human gut, there are some notable exceptions. Some of the more important zoonotic bacterial species that have caused illnesses in humans are salmonellae, campylobacter, and pathogenic strains of Escherichia coli. In particular, the CDC has determined that Campylobacter jejuni is the etiologic agent that is responsible for the majority of foodborne illnesses in the United States.²⁷ C jejuni infections typically are self-limiting and rarely require specific treatment. However, a small subgroup of patients have developed more serious sequelae, such as Guillain-Barre syndrome, an acute neurologic condition associated with skeletal muscle paralysis. The exact mechanism by which C jejuni predisposes some patients to develop Guillain-Barre syndrome currently is unknown. 

Heightened awareness of potential zoonotic bacterial contamination has occurred recently, as a result of reported “outbreaks” of Salmonella typhimurium DT104. This particular bacterial strain is unique, having become resistant to five commonly used antibiotics (ampicillin, chloramphenicol, sulfonamides, streptomycin, and tetracyclines), raising the concern that if a human developed an infection from exposure to S typhimurium DT104, the physician would have a very limited number of effective antibiotics for treatment.²⁸ The emergence of multiple-drug-resistant zoonotic bacteria has been attributed, in part, to antibiotic use in food-producing animals, causing some to question the rationale (particularly for growth enhancement purposes). However, although antibiotic resistance among zoonotic pathogens has increased over the approximately 40 years that antibiotics have been used, there are few reported cases of antibiotic-resistant zoonotics that have posed a threat to human health. 

Data from the National Antimicrobial Resistance Monitoring System indicate that the prevalence of S typhimurium DT104 has decreased over the past 12 months, while antibiotic use in animals has continued, suggesting that antibiotic usage in animals did not provide selective pressure for the continued prevalence of this bacterium. Antibiotic use in animals is essential to produce the quantity of food that consumers desire at affordable prices. Antibiotics also reduce the bacterial flora in the gastrointestinal (GI) tract of the animals, enhancing the utilization of feed (decreased manure production) and minimizing the total number of bacteria to which the carcass might be exposed at slaughter. Thus, under the current food-animal production practices in the United States, there is a need to continue the use of antibiotics to promote animal health and growth. There are risks posed by contamination of foods of animal origin by bacteria that have not acquired resistance to antibiotics. Indeed the largest recall of ground beef in the United States occurred in 1997 at the Hudson facility in Colorado, which was due to contamination by E coli O157:H7.²⁹ Typically E coli strains are considered to be commensal organisms, inhabiting the normal intestinal flora of humans and animals. The E coli O157:H7 strain is particularly worrisome due to its having acquired a gene from another pathogenic bacteria (shigella). This acquired gene allows E coli O157:H7 to produce a potent toxin that induces abdominal cramping, GI bleeding, and diarrhea in infected patients. More importantly, about 10% of patients develop hemolytic uremic syndrome, a life-threatening complication that is characterized by acute renal failure, hemolytic anemia, and thrombocytopenia.³⁰ These sequelae are particularly serious in children and the elderly. Mortality occurs in about 5% of cases, but approximately 50% of survivors display some persistent deleterious effects. 

Although antibiotic resistance among E coli O157:H7 is not widespread, treatment focuses on rehydration and supportive therapy, and therapy with antimicrobials or anticholinergics is not recommended, since they have not been shown to alter the course of the infection or recovery.³¹ Recent incidents of foodborne microbial contamination ultimately led the USDA in 1998 to implement the HACCP program. Bacteria occasionally have been observed to contaminate fruits and vegetables. Typically this is caused by the presence of rodents and other wild animals that might be present in close proximity to areas where crops are grown and/or stored. Indeed a recent outbreak of E coli O157:H7 was traced to unpasteurized apple juice, and the source of the contamination was believed to be caused by the inclusion of apples that had fallen to the ground and subsequently had become contaminated with deer feces.³² This outbreak has led to widespread changes in the handling and packaging of fresh juices. Juices should be pasteurized at the time of packaging, and consumers should follow label instructions for storage conditions and shelf-life (unopened and after opening). 

In other studies, it was found that E coli O157:H7 contamination invades the inner tissues of radish sprouts³³ and lettuce,³⁴ highlighting the importance of thoroughly washing fresh fruits and vegetables prior to consumption. Eggs have long been recognized as a potential source of Salmonella enteritidis, which accounted for the largest number of outbreaks of bacterial contamination during the period from 1988 to 1992.³⁵ Contamination is initiated when the ovary of the chicken becomes infected by S enteritidis which is prevalent in many chicken houses due to carriage by rodents. Consequently, measures to control rodent populations have been very effective in minimizing the contamination of eggs. More importantly, public education campaigns have been very successful in their efforts to curtail the consumption of raw eggs and related products such as salad dressings and eggnog. It also is important to know that S enteritidis, unlike S typhimurium DT104, generally has not acquired antibiotic resistance, and infections typically respond to therapy with a number of antibiotics. 

Another pathogenic bacterium that is known to produce foodborne illnesses is Listeria monocytogenes. Listeriosis is not as common as campylobacteriosis or salmonellosis, but is of concern due to the relatively high rate of mortality that has been estimated to occur in 25% to 30% of cases.^36,37 L monocytogenes is widely distributed among foods, particularly in dairy products (raw milk, cheeses), meat, poultry, and seafood.³⁸ Fungal contamination also is problematic for certain foods. There are hundreds of strains of fungi that potentially produce compounds which are harmful to humans. These compounds are termed mycotoxins. Many mycotoxins do not pose a threat to human health in the quantities in which they are present in foods. However, there are several notable exceptions. In particular, the presence of moisture in harvested corn and other grains is known to promote the growth of Aspergillus flavus and related strains. Apart from obvious concerns about spoilage, A flavus produces the mycotoxin aflatoxin, which is considered to be one of the most potent hepatocarcinogens identified. Consequently, corn harvests are routinely monitored for aflatoxin content, and those with contamination exceeding 20 ppb cannot be used for human consumption.¹ Peanuts also support the growth of A flavus and may become contaminated with aflatoxin. Consequently, it has been estimated from rodent toxicology studies in 1984 that the consumption of peanuts and peanut products produced 158 cases of liver cancer per year.³⁹ Thus a prudent precautionary measure that consumers should exercise is to store peanut butter under refrigeration, particularly the “natural” brands that do not contain preservatives, to deter fungal growth. 

Another example of a harmful fungal food contaminant is Claviceps purpurea, a species that is particularly noteworthy to pharmacists as they produce the potent ergot alkaloids. The fungus typically contaminates rye and other grains, and ergotism resulting from ingestion of bread made from the contaminated flour was reported as long ago as the Middle Ages. Principally, patients experienced severe vasoconstriction, particularly in extremities, such that limbs became gangrenous and were sloughed off. During the Middle Ages, this phenomenon became known as “St. Anthony’s fire,” and the limbs of affected patients were thought “…to be consumed by the fire of St. Anthony.” Today, preservatives are used extensively in baked goods, and, thus, the risks of exposure to fungi in quantities sufficient to produce adverse health consequences are minimal. However, it is wise for consumers to minimize moisture in areas where baked goods are stored, and to inspect these products for signs of fungal growth prior to their consumption. It is interesting to note that ergotism currently is a common problem for horses and livestock when consuming grasses such as tall fescue, which often contains fungal contamination.⁴⁰ Other examples of mycotoxins that have caused illnesses in humans include fumonisin, ocratoxin, and trichothecene.⁴¹  

Parasites also can potentially contaminate foods and pose a human health threat upon consumption. This situation has been highlighted recently by the discovery that raspberries imported from Guatemala were found to be contaminated with Cyclosporia, a coccidial parasite that induces severe watery diarrhea in humans following ingestion.⁴² Fortunately, the source of the affected berries was identified and further importation was terminated. This situation underscores the necessity for consumers to inspect foods for overt signs of contamination and to wash fresh fruits and vegetables thoroughly with water prior to consumption. 

Other foods commonly harboring parasites include snails and certain shellfish, and consumption of these contaminated foods typically result in chronic human infestations. There are certain areas of the world where such infestations are endemic. For example, consumption of snails in parts of England have been associated with the development of hepatitis due to infestation by the parasite Fasciola hepatica.

 Concerns for nonmicrobial contamination of foods also have arisen recently. Probably the greatest single issue that has attracted worldwide attention in recent years has been mad cow disease and the related disease scrapie, which occurs in sheep.^43-46 Mad cow disease and scrapie are examples of transmissible spongiform encephalopathies (TSEs), a class of neurologic degenerative diseases caused by prions and for which therapy currently is not available.46 Prions are relatively small (ca. 33 to 35 kDa) proteins that are found in normal proteins that are found in normal mammalian systems and their functions are as yet unknown. However, the prion responsible for TSEs (designated PrPsc) has an altered protein structure that renders the PrPsc resistant to protease degradation. Thus, it is hypothesized that this altered structure permits the PrPsc to accumulate and ultimately induce TSE in affected animals.⁴⁷  

Scrapie has been known in Britain, France, and Germany for 200 years.⁴⁸ The more recent development of mad cow disease with symptoms similar to scrapie in affected sheep caused researchers to question whether a common etiologic factor was responsible, which was transferred across the species.⁴⁹ Indeed, a widespread practice in animal agriculture was to “render” the carcasses of sheep that were rejected for human consumption into the diet that was fed to cows. In this way, rendering permitted the recovery of animal protein that otherwise would be lost.⁵⁰ Since rendering practices were identified as potential threats to TSE transmission, a worldwide moratorium on rendering of animal protein currently is in place.⁵¹  

In the United States, mad cow disease has not been observed, principally due to restrictions on imported beef from countries where the disease is prevalent (especially England and Switzerland). 

However, TSEs also are observed to occur in humans, and Creutzfeldt-Jakob disease (CJD) is one particular TSE that has raised concerns about a potential link to mad cow disease. A new variant of CJD recently has appeared among humans with symptoms that resemble those observed in diseased cows, raising fears that humans may acquire CJD from consuming beef from cattle that carry the aberrant PrPsc protein.^52-55 Since there is no effective therapy for CJD, extensive surveillance programs to detect/eradicate affected cows currently are under way in countries where the disease is prevalent. In this way, the potential risk of incorporating PrPsc into the food supply and subsequently providing for its transfer to humans can be minimized. 

As a final consideration, environmental contaminants also can accumulate in foods and potentially lead to human illness, if consumed in sufficient quantities. For example, it is well known that many inland waterways contain natural and man-made deposits of heavy metals (eg, mercury) in their sediments, and these metals tend to become concentrated within the food chain. Consequently, health departments in most states currently recommend that the consumption of certain species of fish (typically bass and pike) be limited to one serving per week. This is particularly true for children and during pregnancy, because of the selective toxicity of heavy metals to the developing hematopoietic and neural tissues. 

Another example of environmental pollutants that can become concentrated in fish are the polychlorinated biphenyl compounds, or PCBs. These compounds had been used extensively in electronic components before their carcinogenicity became apparent. Although drastic limitations on the usage of PCBs have since been enacted, PCBs collectively are lipophilic and resistant to bioremediation, and thus remain widely distributed in the environment.⁵⁶ Consequently, following ingestion by fish, PCBs are stored in adipose tissue where they become concentrated over time. Therefore, it is prudent for consumers to avoid consumption of fish that are predominantly bottom-feeders (eg, flounder) or have substantial fat stores (eg, mackerel, bluefish). Alternatively, removal of fat prior to cooking does help to reduce the potential consumption of PCBs and other lipophilic xenobiotics.

The preceding sections have mentioned programs aimed at detecting the presence of chemical contaminants and specific actions that can be taken to avoid ingestion. These include surveillance by USDA-FSIS, FDA-CFSAN, and other agencies to detect violative residues in meats and produce, and proper handling and storage of foods by food producers, retailers, and consumers. Since the majority of foodborne illnesses in the United States are caused by microbial contaminants, there are particular ongoing activities that focus on their identification and eradication.

Concerns have been voiced that the routine use of antibiotics in food-producing animals may exert selective pressure on zoonotic pathogens to develop resistance to the antibiotics.⁵⁷ This hazard has existed ever since antibiotics were introduced for use in animals more than 40 years ago, and studies have shown that no adverse human health consequence has been directly linked to these uses of antibiotics. Researchers generally accept that the use of antibiotics in animals (or for any use) presents a potential human health hazard, but no quantitative assessment has been performed to determine the actual risk that the hazard will result in an adverse human health outcome.⁵⁸ Several scientific groups, including the FDA-CVM and the Center for Food and Nutrition Policy at Georgetown University, presently are conducting these critical risk- assessment studies to determine if antibiotic use in animals does indeed pose a threat to human health. In contrast to the science-based approach to risk assessment in the United States, events in Europe generally have followed less objective “precautionary principles.”

There are a number of underlying factors that account for the recent increases in reported cases of foodborne illnesses. The increased reliance on intensive farming practices and our increased ability to detect foodborne pathogens have been discussed in preceding sections. Another contributing factor is compromised immune status. In recent years, there have been increasing numbers of immunocompromised patients in our communities, principally due to AIDS and in patients undergoing immunosuppressive therapy for organ transplantation. In these individuals, opportunistic infections are common and occur following exposure to pathogen loads that otherwise would not affect healthy individuals. For immunocompromised individuals, it is essential that foods are cooked thoroughly to assure that pathogen loads are essentially eliminated.⁵⁹  

Elderly populations also present a substantially increased risk for developing foodborne illnesses. Several underlying factors account for this increased risk, which include compromised immune status, poor nutrition, exposure to long-term care facilities, and increased usage of antibiotics and other medications. 

Children are also at substantially greater risk of acquiring foodborne illnesses. Recognition of the increased susceptibility of children to foodborne chemical toxins led to passage of the FQPA in 1996. 

Another risk factor for acquiring foodborne illness is international travel. Pharmacists are well aware of the risks of acquiring “Montezuma’s revenge,” or travelers’ diarrhea associated with consumption of contaminated food and/or water in many Central and South American countries. In many of these countries, antibiotics often are allowed to be used indiscriminately for humans and animals, resulting in an overgrowth of resistant bacteria. Consequently, many travelers returning to the United States have sought medical treatment for infections acquired while abroad. Treatment of resistant bacterial infections can be particularly difficult, often requiring extended treatment with more powerful antibiotics that may present additional risks of adverse drug reactions. For prophylaxis against travelers’ diarrhea, some physicians have elected to use antibiotics prior to and during travel outside of the United States. However, this practice is not recommended, because of the likelihood of treatment failure and the additional selective pressure that the antibiotics contribute to the development of antibiotic resistance.

To minimize hazards associated with antibiotic use in animals, worldwide efforts are under way to develop/implement guidelines for the prudent use of antibiotics in food-producing animals. Groups such as the World Health Organization (WHO) and various national and international veterinary groups have drafted guidelines for the prudent use of antibiotics in food-producing animals (Table 1). These guidelines assist veterinarians and animal caretakers to use antibiotics in a careful, controlled manner to maximize their benefits while minimizing the potential for antibiotic resistance to develop. In addition, the companies that manufacture antibiotics for food-producing animals have instituted research programs to identify new and novel approaches to maintaining animal health that ultimately may replace the need for antibiotics.

It is important for consumers to appreciate the types of potential microbial contamination that they might encounter in their foods, and which foods to be particularly concerned about. Table 2 lists some of the more common foodborne pathogens and the characteristics of their outbreaks.⁶⁰ Contamination can occur at numerous points throughout the processing of meats, and particularly in slaughterhouses. 

In 1998, the federal government implemented the HACCP program, aimed at controlling potential contamination of animal carcasses in slaughterhouses.5 As of January 26, 1998, all slaughterhouse facilities with more than 500 employees (approximately 75% of all facilities) were required to be in compliance with the HACCP regulations (smaller operations were given until January 1999 to be in compliance). Surveillance figures for 1998 indicate that in the 6 months of HACCP implementation, the incidence of contamination in slaughterhouses has fallen by approximately 50% compared with that observed in prior years.⁶¹ This translates to a substantial improvement in food quality that likely will improve in coming years. It is the responsibility of the USDA-FSIS to monitor slaughterhouses to ensure compliance with the regulations stated in the HACCP document. Since 1987, HACCP principles have been utilized for assuring the quality of shellfish, and currently HACCP guidelines are being implemented in aquaculture and seafood processing facilities.⁶²  

An important change has occurred at the USDA in recent years with respect to their approach to inspecting foods for evidence of contamination. Until fairly recently, inspectors utilized organoleptic techniques, relying on the visual appearance of the foods and detectable changes in smell or taste that might indicate potential contamination. Today, inspectors utilize a more science-based approach, where samples are collected and analyzed in a laboratory for evidence of contamination. In this way, not only can residues be detected with a greater degree of sensitivity and reproducibility, but in many cases the inspector is able to compare data collected from numerous facilities to determine a particular source of contamination, where mitigation efforts would be most effective. In addition, this type of surveillance permits a particular problem to be traced forward through channels of distribution. This is particularly important to facilitate the recall of a product if the situation is warranted.

In recent years, another option to treat microbial contamination in foods has been approved for use in beef and poultry by the USDA. This technique, referred to as “cold pasteurization,” relies on the irradiation of foodstuffs with x-ray or gamma radiation.⁶³ These high-energy rays (2 to 7 kGy) penetrate the surface of the foods and perturb the electronic structure of certain molecules in the foods, causing their ionization. In many cases, the resulting ions are capable of attacking and killing bacteria in the vicinity where they are produced. Thus, food irradiation is an effective means of killing foodborne bacteria, and because this occurs without increasing the temperature of the food, the structure and/or texture of the food is not appreciably altered. However, recent studies have suggested that food irradiation does induce perceptible changes in the taste of certain foods.⁶⁴ This has contributed to a delay in the widespread acceptance of this process. 

The greatest hurdle to widespread implementation of food irradiation has come from the widely held public misconception that irradiated foods will become “radioactive,” and fears of nuclear contamination have been fueled by accidents that have occurred at nuclear power generators. This fear has no rational basis, because it is not possible for the source of the irradiation to come in contact with the foods, and the ionic particles generated in the foods by the energy from the radiation have a very short half-life. Almost immediately after ions are formed, they react with the bacteria (or cellular macromolecules) in the food, and their energy is dissipated. Thus the effects of food irradiation occur only while the food is being irradiated, and cease upon termination of the radiation process. 

Other concerns have been focused on food production operations, fearing that food irradiation may become a substitute for hygienic practices. Consumers are concerned that it may become economically favorable to terminate many of the safeguards currently in place in favor of irradiating foods at the end of the production chain to kill contaminating bacteria. However, food irradiation advocates are well aware that many of the pathogenic bacterial components remain active after the bacteria have been killed. For example, lipopolysaccharides (LPS) are components of the bacterial membrane of many gram-negative bacteria, which are known to be potent endotoxins. Since irradiation kills bacteria but does not remove it from the food, it is possible that residues from contaminating bacteria (such as LPS) will continue to pose a human health threat. It is important for consumers to know that the position of WHO has always been that irradiation can never be a substitute for hygienic practices. Irradiation is to be used as an additional safeguard to assure that the food supply is safe for human consumption.⁶⁵

Consumers’ Responsibilities

The consumer is the “last” person to exercise corrective measures to avoid the potential consumption of contaminated food. In the same manner that the HACCP program identifies control points to minimize contamination at slaughterhouses, it is important for consumers to know their kitchen and to identify the points where contamination is likely to occur and to implement strategies to prevent contamination. 

The typical kitchen contains substantial reservoirs for microbial contamination, and most consumers do not invest the time necessary to assure that their foods are not compromised by coming into contact with these reservoirs of contamination. Specific areas include the refrigerator, counter tops, and storage areas. It is imperative that foods are stored properly by the consumer, by using sealed containers and appropriate refrigeration. Although programs such as HACCP are very effective in reducing pathogen loads in foods to very low levels, the food will never become sterile. The presence of even one bacterium can result in an unacceptable pathogen load if proper storage procedures are not followed. It is important for consumers to know that freezing will decrease the rate of bacterial growth, but in most cases bacteria will survive (and be preserved by) freezing. The refrigerator should be inspected regularly to ensure that (1) the temperature is maintained between 2Þ and 8ÞC, (2) cooked foods are separated from raw food items, (3) food items are within their expiration dates and spoiled foods are removed, and (4) food spillage and residues are promptly cleaned. Hot foods should never be placed immediately into a refrigerator, as this will increase the temperature in the refrigerator above the acceptable limit of 8ÞC thereby compromising other foods present. Instead, allow foods to cool briefly to room temperature before placing them into a refrigerator. Outside of the refrigerator, it is important also to assure that raw foods are not placed in close proximity to foods that already have been cooked (or, in the case of vegetables and salad, will not be cooked). This prevents the possibility of cross-contamination by bacteria that might be present in raw foods. As an example, cross-contamination often occurs when raw foods are placed on surfaces such as counter tops or cutting boards that are not cleaned before the surfaces subsequently are used to prepare salads and other foods not intended to be cooked. Transfer also occurs often when juices from raw meats spill onto surfaces and are not immediately cleaned. 

Proper cooking procedures are very important to eliminate potential microbial contaminants from foods prior to ingestion. The potential for incomplete cooking by microwave ovens underscores the importance for consumers to ensure that their foods are prepared properly. This is particularly important for meats and is done by monitoring the internal temperature to assure that a minimum temperature of 65ÞC is attained. For certain meats, such as pork, which have been associated with contamination by particular microbes that are known to resist thermal decomposition, higher temperatures and/or longer exposure times are recommended. Today, many foods are labeled with precautionary instructions that outline the recommended cooking times. A common error that consumers often make (particularly during summer barbecues) is to overcook the exterior, conveying the appearance of adequate cooking without attaining the necessary internal temperature. This problem can be corrected by cooking foods for longer times at lower temperatures. 

Environmental sources of contamination cannot be emphasized enough. In a recent study, researchers attempted to identify potential sources of salmonellosis for children in the home. A total of 526 samples from 50 homes were obtained, and salmonella isolates were characterized by serotype and their location within the home environment. Data indicate that an identical serotype was found in dirt surrounding the front doors (4), on household members (3), vacuum cleaner (1), animals/pets/insects (1), and a refrigerator shelf (1). Interestingly, the only salmonella isolated from food sources was found in a piece of cheese that had been handled numerous times by family members. Researchers concluded that for children, contacts with infected individuals, pets, and other environmental sources appear to pose a substantially greater risk of transferring salmonella compared with contaminated foods. Thus, it is important to recognize the multiple sources of potential contamination within the home and to minimize potential microbial contact and/or transfer to foods.⁶⁶ In most cases, thorough and frequent hand washing is the most effective remedial action. 

In addition, a frequently neglected source of potential microbial contamination that does not necessarily reside in the kitchen is the family pet. Studies have shown that healthy companion animals often can be asymptomatic carriers of bacteria that are potentially harmful to humans. Pets should be kept away from the kitchen and other areas where foods are handled and/or stored. Care should be exercised when handling pet play toys, food dishes, and particularly when cleaning litter boxes. All of these objects potentially can serve as fomites for the transfer of bacteria and parasites. Hands should be washed thoroughly with soap and hot water immediately after handling these objects.

Few consumers would debate the importance of precautionary measures to maintain safe foods if the underlying reasons for taking precautions were readily apparent. Once the risks of acquiring foodborne illnesses are known, it still can be easy to ignore and/or dismiss them if the consumer does not integrate them into their daily routine. 

The community pharmacist often has opportunities to provide information to consumers about the reasons why a particular procedure is important, and to suggest ways in which the consumer may assimilate a particular procedure into their daily routine. 

One effective approach would be to become an active proponent of food safety, and to take the time to seek out and answer questions that customers may have about a particular concern they might have heard or read about. 

There are many educational resources that are readily available via the Internet. For a variety of reasons, these resources are underutilized by consumers, and the pharmacist can be instrumental in directing consumers to them. The Internet is a useful educational tool. Many web sites contain materials that easily can be downloaded for use as tools to facilitate effective counseling. A list of web sites that pertain to food safety is in Table 3. One particularly useful site is sponsored by the Partnership for Food Safety Education (www.fightbac.org), which provides the Fight BAC program. This program focuses on the four critical elements of safe food handling (clean, separate, cook, and chill), and utilizes brochures and other media tools to get the message across to consumers. Numerous organizations, including schools, hospitals, and food stores, have begun to utilize the resources of the Fight BAC program to educate their customers, and these efforts also should be reinforced by pharmacists.

With the best systems and procedures in place, the reality is that foodborne illness does, and will continue to, occur. When this happens, the pharmacist often is the first health care provider who is consulted. Therefore, it is important for the pharmacist to recognize the symptoms of foodborne illness and to be knowledgeable about appropriate remedial actions. Consequently, the remainder of this article will focus on the treatment of foodborne illnesses.

Foodborne illnesses that result from ingestion of plant toxins or direct/indirect chemical additives generally show signs and symptoms that are indicative of the particular chemical. Occasionally, the extent of the reaction can be minimized by removing the ingested food from the stomach, if ingestion was recent and the suspected toxicant is known (eg, pesticides). 

Syrup of ipecac is the preferred agent for inducing emesis in conscious cooperative patients. The dose for children 1 to 5 years old is 15 mL, 30 mL for older children, and 30 to 60 mL for adults. This must be followed by 6 to 8 oz of water for children and two or three 8-oz glasses of water for adults. Emesis will follow in approximately 20 to 30 minutes. 

Alternatively, gastric lavage can be used to remove ingested anticholinergic compounds (eg, solanaceous plants) that are antiemetic. Additionally, activated charcoal is an effective product for adsorbing most toxins (cyanide is a notable exception) within the GI tract. However, charcoal can adsorb ipecac and render it ineffective; thus, charcoal should not be administered prior to or accompanying ipecac, or until the emetic effects have ceased. Approximately 20 to 50 grams (1 to 2 g/kg) of charcoal should be suspended in 100 to 200 mL of water prior to its oral administration.⁶⁷  

For many food toxins, their absorption from the GI tract is essentially complete prior to the onset of symptoms; thus, the use of emetics to minimize absorption are ineffective. For example, symptoms typically appear from 8 to 15 hours after ingestion of A phalloides. Alternatively, the repeated administration of activated charcoal has been shown to increase the clearance of some chemicals that passively diffuse back into the GI tract or undergo enterohepatic recirculation. In some cases, as for C botulinum toxin, specific antiserum is available that has been shown to be effective. In the case of cholinesterase inhibition resulting from a substantial exposure to organophosphate (but not carbamate) insecticides, pralidoxime methiodide, or 2-PAM, can “reactivate” the cholinesterase enzyme, providing that this antidote is administered shortly after intoxication occurs and before the cholinesterase inhibition becomes “aged.” Once aging has occurred, the inhibition becomes irreversible, and recovery depends on the de novo synthesis of cholinesterase by the patient. However, in most cases of accidental ingestion of anticholinesterase compounds, supportive measures can be used to manage the patient’s symptoms until the etiologic agent is eliminated.

Therapeutic Approaches

The majority of illnesses due to foodborne microbial contamination are managed by patients, who often do not seek medical attention. In fact, many foodborne illnesses are mistakenly attributed to a “virus” or “…something that was going around.” It is important to identify the etiologic agent, in order to determine the source of the infection and if specific therapy might be warranted. This can be done in a clinical laboratory from a stool sample, from which the etiologic bacteria can be cultured and its phylogenetic identity and antibiotic susceptibilities determined. Antibiotics should not be used routinely for acute bacterial diarrhea, which have little effect on the course of the disease and may prolong the asymptomatic carrier state. Nonetheless, antibiotics often are prescribed for empiric therapy of infectious diarrhea, particularly for severe symptoms or for patients who may pose a substantial public health risk (eg, food handlers). 

For salmonellosis, ampicillin is considered to be the drug of choice (1 gram orally every 6 hours for 4 weeks). Patients who are allergic to penicillins may require chloramphenicol (1 gram orally every 6 hours for 4 weeks). Culture and sensitivity determinations should be performed prior to instituting antibiotic treatment, since many salmonella strains have developed resistance to ampicillin and/or chloramphenicol. Alternatively, resistance of salmonellae to the newer fluoroquinolones has not been observed and, thus, they may be a preferred alternative. 

Shigellosis may be treated with either trimethoprim-sulfamethoxazole (160 mg/800 mg orally twice daily for 7 days) or ampicillin (500 mg orally every 6 hours for 7 days). Oral tetracycline also may be considered, but many shigella strains commonly are resistant to the tetracyclines. 

Anticholinergic compounds such as loperamide, diphenoxylate/atropine, or paregoric occasionally are used to decrease GI motility. These products should be used cautiously however, since they may prolong the course of infection with many pathogens such as shigella or parasitic infestations such as Giardia lamblia. Antimotility therapy also may predispose the patient to develop toxic megacolon, an infrequent sequelae to enterocolitis due to infection, C jejuni and other enteric pathogens. Cryptosporidiosis is now recognized as a common diarrheal illness especially in children and homosexual males. The disease is manifested by frequent watery nonbloody stools that usually resolves in several days to a few weeks. Currently there is no effective treatment.⁶⁸

Supportive Measures

Chronic diarrhea should be managed by rehydration. This can be done by the oral administration of fluids containing electrolytes and sugars, but milk products should be avoided since acquired lactase deficiency is common. 

Probiotic preparations are often used as a preemptive measure to maintain the intestinal flora of individuals.⁶⁹ In this way, potential foodborne bacterial pathogens would have to compete with the endogenous flora, and thus, their colonization potential becomes reduced. Products typically contain nonpathogenic strains of Enterococci or Lactobacillus acidophilus, and are available in the form of tablets, capsules, or yogurt.

Foodborne illnesses, in most cases, are self-limiting disorders of the GI tract that typically require symptomatic treatment until the etiologic agent is eliminated. Although patients rarely seek professional medical care for mild symptoms, it is important to recognize the symptoms of a more serious underlying pathology for which medical treatment is essential. The pharmacist is ideally positioned in the professional community to consult with customers and to clarify their treatment options. 

More importantly, the pharmacist is available for consultation before a potential exposure to foodborne microbes and/or chemicals might occur. This is one of the best applications of pure preventive medicine, and one that easily can be integrated into one’s daily activities. The majority of consumers have no concept of the extent to which pathogenic bacteria are present in their environments and the relative ease with which transfer can occur between contaminated surfaces and our food. By acknowledging these risks, the pharmacist can recruit the consumer as an active participant in the ongoing battle against foodborne contamination. In preparation for battle, there are numerous resources available through the Internet and other sources to serve as armaments that should be integrated into the consumers’ daily routine. If the preventive strategies should fail, symptomatic treatments usually are adequate until symptoms abate. In these instances, attempts should be made to identify why the preventive approach failed in order to take corrective actions against the next microbial onslaught. The pharmacist can have an important impact on the health maintenance of his/her customers.

Return to Introduction

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