Chapter 19: Food Safety

The safety of the food supply is important and complex. Reports of food-borne illnesses are in the news almost daily. An outbreak of E. coli O157:H7 linked to romaine lettuce in 2018 sickened over 200 people in 36 states with 5 deaths.^[1] Food safety topics also include pesticides, packaging, storage, genetically modified organisms, and food additives.

Federal oversight of food supply safety is divided among more than sixteen agencies.^[2] The major agencies are the United States Department of Agriculture (USDA) for meat, eggs, poultry products and the Food and Drug Administration (FDA) for most other foods. Division of oversight is complicated; for example, frozen cheese pizzas are regulated by a different agency than frozen pizzas with meat! The Environmental Protection Agency (EPA) regulates pesticides and other environmental chemicals that may end up in food. The Centers for Disease Control (CDC) becomes involved when food-borne illnesses are discussed.

Foodborne Illness

Foodborne illness, including what is commonly called food poisoning, is very common. A 2019 study by the CDC estimates that around 10 million cases of foodborne illness attributable to six common causes occurred in the United States each year. Most people affected by foodborne illness in 2019 did not seek medical attention, but 53,000 were hospitalized and 931 died.^[3] Most foodborne illness is caused by microbial pathogens including viruses, bacteria, protists, and small worms. Illness can be due an active infection by an organism (foodborne infection), or due to a toxin produced by an organism and ingested with food (foodborne intoxication). Antibiotics can kill bacteria but will not treat the effects of a toxin.

Symptoms of foodborne illnesses can vary in type and severity; common symptoms include nausea, vomiting, abdominal cramps, diarrhea, and fever. Bloody diarrhea, high fever, signs of dehydration (dizziness, dry mouth, infrequent urination), or diarrhea lasting longer than three days are reasons to contact your health care provider.^[4]

Causes of Foodborne Illnesses

The most common causes of food poisoning, nearly 60% of cases, is norovirus. [3,5] With common symptoms (vomiting, nausea, diarrhea, fever, headache) and a typical onset 12-48 hours after exposure, this disorder is sometimes called the “stomach flu.” Treatment is supportive – hydration by drinking electrolyte solutions or, if needed, intravenous fluids. Most people recover after one to three days. Norovirus spreads easily: touching a contaminated surface and then touching the mouth, eating contaminated food, or sharing food/utensils with someone infected can transfer the virus. Because it has a protein-based outer shell, norovirus is not easily destroyed by hand sanitizer. The best prevention is frequent hand washing with soap and water.

Other common foodborne pathogens include the bacteria species Salmonella spp., Clostridium perfringens, Campylobacter spp. and Staphylococcus aureus. Organisms causing fewer but more serious illnesses include the bacteria Vibrio spp, Clostridium botulinum, E. coli, and Listeria spp. Listeria is particularly worrisome for those who are pregnant as they are more likely to become infected and the infection can lead to miscarriage, still birth, preterm labor, or even death in newborns. Table 19.1 summarizes the most common foodborne pathogens and their symptoms.

Table 19.1 Food Poisoning Causes, Time of Onset, and Symptoms. Source: Food Poisoning Symtoms | Food Safety | CDC / Public Doman

Foodborne Germ	Typical Time of Onset and Symptoms	Common Sources
Staphylococcus aureus (Staph)	30 minutes – 8 hours Nausea, vomiting, stomach cramps, diarrhea	Foods that are not cooked after handling, such as sliced meats, puddings, pastries, and sandwiches.
Vibrio	Within 24 hours Watery diarrhea, nausea. Stomach cramps, vomiting, fever, chills	Raw or undercooked shellfish, particularly oysters
Clostridium perfringens	6 – 24 hours Diarrhea, stomach cramps. Usually begins suddenly and lasts for less than 24 hours.	Meat, poultry, gravies, and other foods cooked in large batches and held at an unsafe temperature
Salmonella	6 hours – 6 days Diarrhea, fever, stomach cramps, vomiting	Raw/undercooked poultry and meat; eggs; unpasteurized milk and juice, raw fruits, and vegetables Many animals, including poultry, reptiles, amphibians, small mammals
Norovirus	12 – 48 hours Diarrhea, nausea, stomach pain, vomiting. Fever, headache, body aches also possible.	Contaminated food like leafy greens, fresh fruits, shellfish (such as oysters), or water Infected person; touching contaminated surfaces
Clostridium botulinum (Botulism)	18 – 36 hours Doubled/blurred vision, drooping eyelids, slurred speech, difficulty swallowing and breathing, muscle weakness, paralysis. Symptoms start in the head and move down as the illness gets worse	Improperly canned or fermented foods, usually homemade. Prison-made illicit alcohol.
Campylobacter	2 – 5 days Diarrhea (often bloody), stomach cramps/pain, fever	Raw or undercooked poultry, raw (unpasteurized) milk, and contaminated water Pets, including cats and dogs
Escherichia coli (E. coli)	3 – 4 days Severe stomach cramps, diarrhea (often bloody), and vomiting. ~5-10% of people with this infection develop a life-threatening complication.	Raw/undercooked ground beef, unpasteurized milk and juice, raw vegetables (such as lettuce), raw sprouts, contaminated water
Cyclospora	1 week Watery diarrhea, loss of appetite,  weight loss, stomach cramps/pain, bloating, increased gas, nausea,  fatigue.	Raw fruits or vegetables and herbs
Listeria	2 weeks Fever and flu-like symptoms (such as muscle aches and fatigue), headache, stiff neck, confusion, loss of balance, and seizures Pregnant women: can lead to miscarriage, stillbirth, premature delivery, or life-threatening infection of newborn. Contacting a doctor in cases of fever and unusual fatigue/aches is recommended.	Soft cheeses, raw sprouts, melons, hot dogs, pâtés, deli meats, smoked seafood, unpasteurized milk.

Effective food safety procedures disrupt conditions that allow dangerous bacteria to grow. Most bacteria that cause human disease grow optimally in the ‘danger zone’ temperature range of 40^o-140^oF (4-60^oC). Leaving food in this temperature range for more than two hours increases the risk of foodborne illness. Refrigeration, freezing or heating of food can inhibit growth. Cooking can kill microorganisms and destroy some types of bacterial toxins.

Bacteria also require water to grow; dehydrating foods prevents bacterial growth. Acidic conditions, less than pH 4, also prevents growth of most microbes, although some thrive at low pH. Finally, most bacteria grow best in the presence of oxygen, but a few, including the microbe that causes botulism can grow in sealed jars or cans.

Other organisms that cause food poisoning include fungi and algae and their toxins. The “red tide” blooms from algae can lead to toxin in shellfish, which can sicken people and other animals.

At-Risk Groups

The risk of serious illness depends on the microorganism, the amount consumed, and a person’s overall health. Groups with a higher risk for severe complications include infants, young children, elderly people, and pregnant women. Other high-risk people include those with compromised immune systems due to illness or medications or with long-term steroid use for asthma or arthritis. Exposure to contaminated food could seriously impact diabetics, cancer patients, people with liver disease or low stomach acid or previous stomach surgery. Everyone should handle food carefully, cook food thoroughly, and be alert to avoid exposure.

Preventing Foodborne Illness

The United States Department of Health and Human Services website, www.foodsafety.gov, contains information about food safety. Four guidelines for preventing foodborne illnesses are clean, separate, cook, and chill.^[6]

Clean

Wash hands frequently before, during, and after food preparation, especially after handling raw meat, eggs, or seafood, after using the bathroom, after touching garbage, animals, human or animal waste, after being around someone who is ill, after sneezing, coughing, or blowing your nose, and before and after treating a wound.

Effective handwashing only requires soap and water. Antibacterial soaps are safe for long-term us, but their overuse may lead to antibiotic-resistant organisms. To be most effective, remove rings and bracelets that may harbor bacteria. Wash for at least twenty seconds – the length of time it takes to sing the “Happy Birthday” song twice; clean under your nails and between your fingers. Rinse hands and dry thoroughly.

Alcohol-based hand sanitizers should be used when washing is not possible, but hand washing is more effective at removing microbes. In addition, hand sanitizers are not effective against all foodborne pathogens, including norovirus. Dirt and grease on hands lowers the effectiveness of hand sanitizers, which are most effective on clean hands.

Wash food preparation surfaces, cutting boards, and utensils with hot soapy water after each use. Wash dish clothes frequently in hot water. Wash fruit and vegetables under clean running water. Firm produce can be scrubbed. Meat, eggs, or poultry should not be washed.

Separate

Limit cross-contamination between foods likely to be contaminated and other foods. Raw meat, poultry, seafood, and eggs should be transported and stored in separate, sealed, leakproof containers and prepared in separate spaces, using their own cutting boards and utensils. Produce and food that will not be cooked should be stored, handled, and prepared in a separate space. Cooked food and raw food should be kept apart. Wash anything in your kitchen that comes in contact with eggs, poultry, seafood, or meat immediately with hot soapy water.

Cook

Use a food thermometer to ensure that food is cooked to the proper temperature to kill microorganisms. Measure temperature in the thickest part of the food, avoiding air bubbles, bone, or gristle in meat. When microwaving, rotate the dish and stir contents several times to ensure even cooking and allow the dish to rest to evenly distribute heat. Safe minimum cooking temperature varies depending on the type of food:

• Seafood should be cooked to an internal temperature of 145°F
• Beef, lamb, and pork to 160°F
• Ground chicken and turkey, whole poultry, and pieces to 165°F

Once cooked, food should be stored above 140^oF (on a heated table, warming drawer, chaffing dish or slow cooker) or below 40^oF (in a refrigerated dish or ice bath) until consumed. In the range between 40^oF and 140^oF, the “danger zone” for foodborne illness, bacteria multiply readily. Food should be left at these temperatures no longer than 2 hours, with an hour or less for temperatures above 90^oF.

Table 19.2 Safe Minimum Cooking Temperatures. Credit: FoodSafety.gov /Public Domain

Food	Internal Temperature (°F)
Ground beef, pork, veal, lamb	160
Ground turkey, chicken	165
Fresh beef, veal, lamb: steaks, roasts, chops (rest time: 3 minutes)	145
Poultry (breasts, whole bird, legs, thighs, wings, ground poultry, giblets, stuffing)	165
Fresh pork and ham (rest time: 3 minutes)	145
Precooked ham (to reheat)	165 (Note: Reheat cooked hams packaged in USDA-inspected plants to 140°F)
Eggs	Cook until yolk and white are firm
Egg dishes (such as frittata, quiche)	160
Leftovers and casseroles	165
Fish with fins	145 or cook until flesh is opaque and separates easily with a fork
Shrimp, lobster, crab, scallops	Cook until flesh is pearly or white, and opaque
Clams, oysters, mussels	Cook until shells open during cooking

Chill

Although refrigeration and freezing do not kill microorganisms, they slow growth and allow food to last longer. Refrigerators should be between 32^oF and 40^oF. To cool food rapidly when placed in the refrigerator, separate large batches of food, store in shallow containers, and cover loosely until the food is cooled, after which the lids can be tightened, or bags zipped.

To thaw food out of the ‘danger zone’ temperatures, place frozen food in the refrigerator rather than on the countertop at room temperature.

Food Preservation

Traditional food preservation techniques either remove bacteria or convert the food into an inhospitable place for the bacteria. Removing water by salting, sugaring, dehydrating, or smoking prevents bacterial growth. Canning involves removing oxygen, which limits the growth of aerobic bacteria. Some harmful bacteria, such as Clostridium botulinum, are anaerobic, which means they do not require oxygen to live. People who preserve food at home by canning should follow guidelines from organizations such as the CDC. Consumers of all foods – whether from a restaurant, grocery store, or personal pantry – should be alert for danger signs such as bulging cans, spurts of liquid out of a package when opened, unusual appearance or smell. “If in doubt, throw it out!”^[7]

Pasteurization destroys microbes on food by heating a high temperature for a short period of time. It is commonly used for milk and juice.

Irradiation exposes foods to ionizing radiation to kill microorganisms and insects. This extends the life of the food and sterilizes the packaging. Irradiation does not cause food to become radioactive and does not change the texture, taste, or appearance of food. The FDA has evaluated the safety of irradiated food for more than 30 years and has found the process to be safe. The World Health Organization (WHO), CDC and USDA endorse the safety of irradiated food. The FDA requires that all irradiated food must be labeled with a Radura symbol and the statement “Treated with radiation” or “Treated by irradiation” (Figure 19.3).

Food Additives

Food is naturally composed of chemicals; food additives are specific chemicals added for a variety of reasons. Although adding chemicals to foods may sound ‘unnatural,’ even home cooks keep food additives in the home. Common examples are table salt, baking powder, food coloring for cake frostings, and cornstarch for thickening. Additives can be naturally derived or made synthetically; they serve many roles including

• nutritional fortification
• preservation
• flavor enhancement
• color or dye

The FDA has regulated food additives since 1958. Many additives in use at that time were designated as “Generally Recognized as Safe” (GRAS). New additives are tested before approval. Additionally, the FDA monitors consumers’ adverse reactions to additives. This Adverse Reaction Monitoring System (ARMS) has led to additional studies of compounds such as sulfites and aspartame.

Some food additives are micronutrients. The FDA requires refined flour and rice to be enriched with the B vitamins thiamin, riboflavin, niacin, and folate, as well as iron. Similarly, iodine has been added to salt and vitamin D has been added to milk since recommendations were made in the twentieth century to address public health issues of iodine deficiency and rickets. Vitamins C and E help preserve food by preventing oxidation.

Other preservatives increase shelf-life and help prevent food waste. of products. Some preservatives such as sulfites act as antimicrobial agents.

Table 19.3 Common Food Additives. Credit: Types of Food Ingredients, FDA/ Public Domain. Accessed February 15, 2026.

Types of Ingredients	What They Do	Examples of Uses	Names Found on Product Labels
Preservatives	Prevent food spoilage from bacteria, molds, fungi, or yeast (antimicrobials); slow or prevent changes in color, flavor, or texture and delay rancidity (antioxidants); maintain freshness	Fruit sauces and jellies, beverages, baked goods, cured meats, oils and margarines, cereals, dressings, snack foods, fruits, and vegetables	Ascorbic acid, citric acid, sodium benzoate, calcium propionate, sodium erythorbate, sodium nitrite, calcium sorbate, potassium sorbate, BHA, BHT, EDTA, tocopherols (Vitamin E)
Color Additives	Offset color loss due to exposure to light, air, temperature extremes, moisture, and storage conditions; correct natural variations in color; enhance colors that occur naturally; provide color to colorless and “fun” foods	Many processed foods, (candies, snack foods margarine, cheese, soft drinks, jams/jellies, gelatins, pudding, and pie fillings)	FD&C Blue Nos. 1 and 2, FD&C Green No. 3, FD&C Red Nos. 3 and 40, FD&C Yellow Nos. 5 and 6, Orange B, Citrus Red No. 2, annatto extract, beta-carotene, grape skin extract, cochineal extract or carmine, paprika oleoresin, caramel color, fruit, and vegetable juices, saffron
Flavors and Spices	Add specific flavors (natural and synthetic)	Pudding and pie fillings, gelatin dessert mixes, cake mixes, salad dressings, candies, soft drinks, ice cream, BBQ sauce	Natural flavoring, artificial flavor, and spices
Flavor Enhancers	Enhance flavors already present in foods (without providing their own separate flavor)	Many processed foods	Monosodium glutamate (MSG), hydrolyzed soy protein, autolyzed yeast extract, disodium guanylate or inosinate
Nutrients	Replace vitamins and minerals lost in processing (enrichment), add nutrients that may be lacking in the diet (fortification)	Flour, breads, cereals, rice, macaroni, margarine, salt, milk, fruit beverages, energy bars, instant breakfast drinks	Thiamine hydrochloride, riboflavin (Vitamin B2), niacin, niacinamide, folate or folic acid, beta carotene, potassium iodide, iron or ferrous sulfate, alpha tocopherols, ascorbic acid, Vitamin D, amino acids (L-tryptophan, L-lysine, L-leucine, L-methionine)
Emulsifiers	Allow smooth mixing of ingredients, prevent separation Keep emulsified products stable, reduce stickiness, control crystallization, keep ingredients dispersed, and to help products dissolve more easily	Salad dressings, peanut butter, chocolate, margarine, frozen desserts	Soy lecithin, mono- and diglycerides, egg yolks, polysorbates, sorbitan monostearate
Stabilizers and Thickeners, Binders, Texturizers	Produce uniform texture, improve “mouth-feel”	Frozen desserts, dairy products, cakes, pudding and gelatin mixes, dressings, jams and jellies, sauces	Gelatin, pectin, guar gum, carrageenan, xanthan gum, whey
pH Control Agents and acidulants	Control acidity and alkalinity, prevent spoilage	Beverages, frozen desserts, chocolate, low acid canned foods, baking powder	Lactic acid, citric acid, ammonium hydroxide, sodium carbonate
Leavening Agents	Promote rising of baked goods	Breads and other baked goods	Baking soda, monocalcium phosphate, calcium carbonate
Anti-caking agents	Keep powdered foods free-flowing, prevent moisture absorption	Salt, baking powder, confectioner’s sugar	Calcium silicate, iron ammonium citrate, silicon dioxide
Humectants	Retain moisture	Shredded coconut, marshmallows, soft candies, confections	Glycerin, sorbitol

Many additives improve the flavor, appearance, or texture of food. Monosodium glutamate (MSG) is an amino acid that activates umami taste receptors. It is found in grocery store products such as “Accent” and is commonly added to meat and stews. Colorings can be natural products (beet juice) or synthetic (tartrazine, also called yellow #5). The mouthfeel of foods can be altered by texturizers such as gelatin or emulsifiers, which keep fats evenly spread throughout the food, like carrageenan. Carrageenan is frequently added to ice cream, soy milk, sour cream, and jellies. Leavening agents like baking soda (sodium bicarbonate) are used in baked goods.

Some food additives have detrimental effects if consumed in large amounts. For example, sulfites cause allergic reactions in a small percent of the normal population and in up to 10% of people with asthma.^[8]

Food Contaminants

Chemical contaminants in the food supply can have detrimental effects on human health.

Pollutants

Chemical runoff from mining, agricultural, and industrial processes can pollute food and drinking water. For example, dioxins are created during the processes of bleaching pulp and paper. Fish living in dioxin-polluted waters can contain significant amounts; human consumption of contaminated fish is associated with increased risk of cancer.

Contamination by some metals increases health risks. Lead, which can be present in drinking water, soil, and air, is associated with physical and mental delays in children. Methyl mercury occurs naturally in the environment and is also produced by human activities. Fish can absorb it, and predatory fish that consume smaller, contaminated fish can accumulate high levels. Mercury poisoning leads to developmental problems in children and autoimmune effects. Minamata disease is named for the Japanese town in which it was identified in 1956, following the release of methyl mercury into surface water near a factory. Many residents developed neurological issues, including numbness in hands and feet, muscle weakness, narrowing of the field of vision, damage to hearing and speech, and ataxia, which is a lack of muscle coordination.^[9]

Polychlorinated biphenyls (PCBs) are man-made organic compounds containing chlorine. Due to their non-flammability, chemical stability, and high boiling points, PCBs were used as plasticizers, insulators, adhesives, finishes, and components of electrical equipment from 1929 until their ban in 1979. Like methylmercury, PCBs can make their way through food webs and become concentrated in animals such as predatory fish. Health effects include physical and neurological developmental damage in children; many are also carcinogens. PCB contamination can affect the immune, reproductive, nervous, and endocrine systems.^[10]

Pesticides

Pesticides are used to control fungal diseases, insects, and other pests. They protect crops and ensure a large yield, but can leave residues. The USDA runs a national pesticide residue monitoring program^[11], which indicates that for most foods and pesticides, the exposure is extremely small. However, exposures are associated with health issues, including cancer. Infants and young children are more susceptible to the hazards than adults. There are also risks in the levels of exposure to pesticides by agricultural workers.

Organic Food

In 2002, the USDA standardized organic labeling. Foods labeled “organic” meet guidelines described in the USDA National Organic Program Handbook. Organic processes are designed to grow food in an ecologically sound manner, maintain soil and water quality, reduce pollution, increase sustainability on the farm, and enable more natural animal behavior in farm animals. Organic farming does not allow synthetic fertilizers, sewage sludge fertilizer, irradiation, genetic modification, growth hormones, or antibiotics for livestock. Pesticide use is limited to natural and a few synthetic pesticides. It is important to note, however, that spraying is allowed by the guidelines, and some organic crops are sprayed more heavily than conventional crops, due to lower efficacy of the sprays. Organic farming promotes crop rotation, erosion control, use of predatory insects instead of pesticides, and outdoor access, organic food, and vaccinations for animals.^[12]

There are four levels of “organic” labels approved by the USDA (see also Figure 19.4).

• “100% organic” foods: all ingredients are organic; no genetically modified organisms (GMOs) allowed; certification required; May use “USDA Organic” seal on packaging.
• “Organic” foods: at least 95% of ingredients are organic; no GMOs allowed; certification required; may use “USDA Organic” seal on packaging.
• “Made with organic” foods: must contain at least 70% organic ingredients with limits on what non-organic ingredients are allowed; certification required; may NOT use “USDA Organic” seal on packaging.
• “Organic Ingredients”: at least one ingredient is organic; may contain GMOs; certification NOT required; may NOT use “USDA Organic” seal on packaging.

Are Organic Foods Healthier?

Data is limited about nutritional and health differences between organic and conventional foods. Systematic reviews of the literature have found no clear consensus differences between organic and non-organic foods in terms of nutritional quality or safety. Some studies do report differences in nutrient content or pesticide residue content, but whether these differences have significant impacts on human health is not clear.^{[13, 14]} Organic foods tend to be more expensive than their conventional counterparts, and all foods sold in the United states must meet the same safety standards.^[15]

Figure 19.4 Organic Labels Explained. Source: USDA Agriculture Marketing Service / Public Domain.

References

1. Jacobs J. Officials Identify a Source in the Romaine Lettuce E. Coli Outbreak. New York Times. Published July 1, 2018. Accessed February 15, 2026. https://www.nytimes.com/2018/07/01/us/romaine-lettuce-e-coli-nyt.html.
2. U.S. Government Accountability Office. Food Safety: A National Strategy is Needed to Address Fragmentation in Oversight. Published January 13, 2017. Accessed April 24, 2021. https://www.gao.gov/products/gao-17-74
3. Centers for Disease Control and Prevention. Estimates: Burden of Foodborne Illness in the United States. https://www.cdc.gov/food-safety/php/data-research/foodborne-illness-burden/ Updated March 19, 2025. Accessed March 4, 2026.
4. Centers for Disease Control and Prevention. Food Poisoning Symptoms. https://www.cdc.gov/food-safety/signs-symptoms/index.html. Updated November 24, 2025. Accessed March 4, 2026.
5. Scallan, E., Hoekstra, R. M., Angulo, F. J., Tauxe, R. V., Widdowson, M., Roy, S. L., Griffin, P. M. (2011). Foodborne Illness Acquired in the United States—Major Pathogens. Emerging Infectious Diseases, 17(1), 7-15. https://dx.doi.org/10.3201/eid1701.p11101.
6. U.S. Department of Health & Human Services. 4 Steps to Food Safety. Last reviewed on Septempter 18, 2023. Accessed February 15, 2026. https://www.foodsafety.gov/keep-food-safe/4-steps-to-food-safety.
7. Centers for Disease Control and Prevention. Home-Canned Foods. https://www.cdc.gov/botulism/prevention/home-canned-foods.html. Updated April 35, 2024. Accessed February 15, 2026.
8. Gunnison AF, Jacobsen DW. Sulfite hypersensitivity. A critical review. CRC Critical Reviews in Toxicology. 1987; 17(3):185-214. PMID: 3556020
9. Minamata Disease: The History and Measures. Ministry of the Environment, Government of Japan. http://www.env.go.jp/en/chemi/hs/minamata2002/. Published 2002. Accessed February 15, 2026.
10. Learn About Polychlorinated Biphenyls. US Environmental Protection Agency. https://www.epa.gov/pcbs/learn-about-polychlorinated-biphenyls. Updated March 2, 2026. Accessed March 4, 2026.
11. U.S. Department of Agriculture. Pesticide Data Program. Accessed February 15, 2026. https://www.ams.usda.gov/datasets/pdp
12. USDA National Organic Program (2015) Introduction to Organic Practices. Accessed Aug 2, 2019 from https://www.ams.usda.gov/sites/default/files/media/Organic%20Practices%20Factsheet.pdf.
13. Komati N, Cravedi JP, et al. Potential Health Benefits of a Diet Rich in Organic Fruit and Vegetables versus a Diet Based on Conventional Produce: A Systematic Review. Nutrition Reviews. August 5, 2024. 83(3): e1101-e1114. https://doi.org/10.1093/nutrit/nuae104
14. Thaise de Oliveira Faoro D, Artuzo FD, et al. Are organics more nutritious than conventional foods? A comprehensive systematic review. Heliyon. March 21, 2024. 10(7): e28288. https://doi.org/10.1016/j.heliyon.2024.e28288
15. Mayo Clinic Staff. Organic foods: Are they safer? More nutritious? https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/organic-food/art-20043880?reDate=02082019 Updated February 28, 2025. Accessed Februry 15, 2026.

Attributions

Adapted by Pattie S. Green, Ph.D. and Jonathan E. Pottle, Ph.D. at Tacoma Community College from Human Nutrition by University of Hawai‘i at Mānoa Food Science and Human which is licensed under a Creative Commons Attribution 4.0 International License. Specifically, the following parts are adapted here:

• Chapter 17. Food Safety Introduction
• The Causes of Food Contamination