Chemophobia is at a Crossroad

By Gary Smith and Keith Belk, Colorado State University 

“Chemophobia” is “an irrational persistent fear that consumption of certain chemicals will cause illness or death”.¹ A “crossroad” is “a critical point where a decision must be made”.¹ The questions at this juncture are:  

1. Which chemicals? 
2. At what dose? 
3. How can we prove they cause illness or early death? 

---

The Delaney Clause: A Regulatory Turning Point 

Heightened consumer concern about the toxicity of chemicals entering our food and beverage supply resulted in Congress updating the Food, Drug, and Cosmetic Act by including a Food Additives amendment (called the “Delaney Clause”), which stated that, “If a synthetic, but not natural, chemical – at any dose – can be shown to cause cancer in laboratory animals, the chemical must be banned”.²  

Why Chemicals Are Added – and How Some Sneak In  

Some chemicals are added to foods/beverages for nutritional benefits (like milk fortified with vitamins A, D, or E); to improve flavor or color (like nitrate); to protect food from oxidizing, decaying, or spoiling (like BHA); and/or to mitigate risk of containing pathogenic microorganisms (like lactic acid).^3,4,5   

There are some chemicals, like contaminants in the environment (e.g., toxic chemicals from the air, soil, and water – or from chemicals applied to plants and animals) that enter our food unintentionally; some dangerous chemicals can form when raw foods are cooked and/or are processed.^3,4,5,6  

The Ames Test and the Rise of Cancer Concerns  

Between 1938 and 1958, the Delaney Clause was enacted sparingly by the FDA, USDA, and EPA, yet many consumers were fixated on possible linkages of synthetic chemicals (e.g., pesticides) to human cancer.⁷ After passage of the Delaney Clause, Dr. Bruce Ames (University of California-Berkeley) pioneered a laboratory procedure to determine which chemicals might cause cancer.⁸  

Every plant (e.g., tomato, potato, bean) naturally makes 50 to 100 chemicals (i.e., pesticides) to kill its predators (e.g., insects, fungi); we eat tens of thousands of them – at much higher doses than in man-made chemicals.⁸ The Ames Test showed that 50% of the naturally occurring pesticides also test positive as causes of cancer.⁸  

Cranberries, DDT, and the Birth of Public Chemophobia  

And then, on Sept. 6, 1958, the “Natural” food movement and the “Chemophobia” craze were born.⁹ It became publicly known that a weed-killer (aminotriazole), which had not passed the “Ames Test”, was being used by cranberry growers. No one got sick or died after eating them, but sales of cranberries plummeted.⁹  

The cranberry episode, Rachel Carson’s book (“Silent Spring”) about songbirds and DDT, and Alar® on apples fueled the flames, causing consumers and activist groups to urge increased governmental oversight regarding the effects of extraneous chemicals in food on human health.^9,10  

Scientific Evidence Challenges the Additive-Cancer Link  

Three things in 1987, 1990, and 1991 attacked the premise that additives are major players in causing human cancer. In 1987, a National Academy of Sciences study concluded that, if a person ate food throughout their life that contained residues of all 28 known oncogenic pesticides combined, his/her risk of having a fatal cancer would increase by less than 1% (0.584%).¹¹  

In 1990, a Food and Drug Administration study determined that the risk of having a fatal cancer would be increased by consuming foods that contained:  

1. Spices and flavorings (by 0.0757%) 
2. Industrial chemicals (by 0.0122%) 
3. Pesticides and environmental contaminants (by 0.0007%) 
4. Antibiotics, hormones, and drugs (by 0.0007%) 
5. Charring during cooking (by 0.0007%) 
6. Mycotoxins (by 0.0001%)¹² 

Reconsidering the Ames Test’s Role in Chemical Policy  

Because the Ames Test used small numbers of test rodents, it administered very high doses; by 1991, 50% of the tens of thousands of natural (inherent in all plants) pesticides, synthetic pesticides, food additives, and industrial chemicals tested positive and were banned by the FDA.⁸ For example, aminotriazole did sometimes cause thyroid cancer in rats, but a rat had to consume 15,000 pounds of cranberries, every day, for its entire life.⁹  

Bruce Ames was the biggest critic of the government’s use of his test, saying it was not “scientifically justified” because it grossly overestimated the carcinogenicity risk of something that would be consumed by humans in much lower quantities.¹³ In late 1991, the U.S. Congress required the FDA to no longer use the Ames Test but to continue to use the Delaney Clause to test for, or regulate, carcinogenicity of synthetic chemicals.¹⁴ 

The Sheer Volume of Chemicals in Our Food Supply  

Only recently have we realized just how many different chemicals there are in the things we drink and eat. In 2020, the Environmental Defense Fund filed a citizen’s petition saying the FDA had not been doing the job Congress intended when it passed the Food Additives amendment.¹⁵ EDF claimed, “The food you eat contains one or more of some 10,000 chemicals allowed to be added to foods – some of which have been linked to developmental, cognitive, and other health problems in babies and adults.¹⁵ Both plastics and chemical additives in plastics can be toxic. Plastic films and containers can contain from 9,936¹⁶ to >10,000¹⁷ unique chemicals used to make plastic (of which more than 2,400¹⁷ are of potential human-health concern) plus more than 240,000¹⁸ microplastic fragments – all of which can leach into the food/beverage it is protecting.^19,20,21  

The Expanding List of Suspected Health Risks  

It is nearly impossible to isolate when, how, or even if, chemical exposures are or are not responsible for human health problems.²² This information vacuum has given rise to a network of consumer advocates, non-profits, independent scientific laboratories, university scientists, and State governments dedicated to informing the public about potential hazards lurking in consumer products.^{22,23,24,25,26,27}  

And they’ve moved on from just claiming that toxic chemicals cause cancer – critics now claim they cause… 

1. High blood pressure 
2. Reduced immune response 
3. Parkinson’s Disease 
4. Dementia 
5. Neurobehavioral issues 
6. Non-Hodgkins Lymphoma 
7. Birth defects 
8. Developmental inhibition 
9. Leukemia 
10. Hyperactivity 
11. Hormone disruption 
12. Fertility 
13. Reproduction problems^{28,29,30,31,32,33} 

Chemophobia Goes to Court  

As a result, personal-injury lawyers have made billions of dollars filing individual or class-action suits against Federal/State/local governments, manufacturers, or wholesalers of environmental contaminants (e.g., air pollution, microplastics, PFAS, paraquat, glyphosate); and food/beverages (e.g., coffee, bottled water, red dye #2, movie-theater popcorn, Chinese food).^{9,18,22,34,35,36}  

It seems that public skepticism and chemophobia cause someone to claim the need to ban a chemical “at the drop of a rat”.⁹ A once exciting scientific journey is now filled with complex and challenging litigious situations that are stifling new ideas and products.³⁷ 

Which Chemicals Are Under Scrutiny Today?  

Which chemicals? In addition to FSIS, FDA, and EPA, there are five States (California, Illinois, Washington, New York, and Missouri) with Food Safety Acts that identify toxic chemicals that could potentially be in our food/beverage supply.^27,47 There are currently 30 specific toxic chemicals under scrutiny; those are: 

The Problem of Ubiquity and Exposure 

Government Agencies do not analyze every product that appears in the food marketplace – let alone how they will affect human health after years of regular consumption.²² Somewhat like “herding cats”, how do we sort out the culprits when there are 10,000 to 20,000 suspects?  

It becomes much more complicated when you consider what’s in the consumer’s market-basket:  

1. Water in a plastic bottle that contains macro-, micro-, or nano-plastic particles 
2. Tomatoes in a plastic bag that contains PFAS 
3. Vegetable soup in a tin-can with a liner containing bisphenol-A 
4. A stack of beef patties separated by interleaving paper containing phthalates 

Assessing Risk: How Much Is Too Much? 

At what dose? To assess the safety of chemicals in food, scientists at FSIS, FDA, and EPA, plus others worldwide (e.g., World Health Organization, FAO-United Nations, European Food Safety Authority), evaluate existing peer-reviewed scientific evidence about the chemical’s safety, as well as how much of a chemical is in the food, and how much a person eats or drinks.^39,46,53,54 The EPA sets the tolerances for all pesticides in all foods/beverages.⁵⁵ The FDA oversees classification for all other chemical adulterants in both FDA- and FSIS-regulated foods, categorizing them as:  

1. Generally Recognized As Safe (GRAS) 
2. Regulated 
3. Banned⁴¹  

States can pass legislation asking the FDA to reconsider the status of additives on its category lists or they can unilaterally ban specific additives.^27,56 

What It Means to Be GRAS, Regulated, or Banned  

To gain recognition as GRAS, a food additive must meet some or all of:  

1. Used by industry prior to 1958 with no evidence of toxicity 
2. Considered to be safe by the expert scientific community 
3. Results of research studies generally available to the public in peer-reviewed scientific journals
4. Approved by the FDA’s Human Foods Program^3,75  

If an additive is not GRAS, it can be used by food manufacturers if the FDA agrees to authorize and regulate it (using dosage constraints). Conversely, the FDA recently revoked its Regulatory status for a certain food additive that was originally GRAS, moved to Regulatory status based on some earlier research findings, and now banned based on recent research evidence that shows “the potential for adverse health effects to humans.”⁵⁶ If the decision is made to Regulate, data are needed to support ADI and MRL dosage constraints. 

The Dose Makes the Poison – But Only If We Measure It 

Any chemical has the potential to be harmful if consumed at an unsafe level.⁴ Hippocrates, “The Father of Human Medicine”, in about 400 BC, is believed to have said “The Dose Makes The Poison”.⁵⁷  

If it’s the dose that makes the poison, we must be exceptionally precise in the quantifying how much of each food additive must be avoided.⁹ To do that, the EPA and FDA determine an Acceptable Daily Intake (ADI), the amount of a chemical that can be ingested by a person on a daily basis over a lifetime without any appreciable health risk, and a Maximum Residue Level (MRL), the maximum concentration of a chemical residue that is acceptable for consumption.^3,30 

How Risk Assessments Are Conducted 

Decisions on categorization (i.e., GRAS, Regulated, Banned) or on dosages (i.e., ADIs and MRLs) are made by the EPA and FDA using peer-reviewed scientific information and results of test-animal studies.^3,56 Dose-effect studies involve use of laboratory animals (e.g., mice, rats, dogs, swine, microswine, monkeys) to collect health information generated from toxicological, microbiological, and pharmacological studies.⁵⁸ These tests look at growth, developmental, behavioral, physical, reproduction, cardiovascular measures, plus genotoxicity via one-, two-, and/or three-generation studies.^30,56,58,59 

Can We Ever Prove Chemicals Cause Harm?  

How can we prove they cause illness or early death? Perhaps we will never know. The science of developing new pesticides, veterinary drugs, food additives, and plastics has vastly outpaced our ability to determine whether these synthetic chemicals affect the health of those who consume them. We can’t prove they don’t because we can’t prove a “negative”; it is impossible to prove that something will never happen.⁶⁰ We can’t prove they do because we can’t use humans as test-animals. 

Scientific Limits and Ethical Barriers 

The EPA and FDA do the best they can, given the hand they are dealt. Of the three kinds of risk-determination: 

1. Observational data (i.e., epidemiological studies) can only help identify “associations” and “hypotheses”.⁶¹  
2. Laboratory test-animal results are nebulous because rats are not “little people”; humans share 50% of their DNA with bananas yet bananas aren’t used to identify doses and create bans.⁹  
3. Randomized, controlled, clinical trials (RCCTs) – the only way cause-and-effect relationships can be determined – using human subjects are “out-of-bounds” and violate obvious Human Use regulatory ethical considerations.⁶² 

A Cautious Approach – But Still No Proof of Harm 

The public should feel comfortable with the fact that the government has used a “just-in-case”, “abundance-of-caution”, and “better-safe-than-sorry” ideology in exercising its jurisprudence.⁵²  

And, we do know that two of the world’s leading scientists on the subject have said there is no proof (i.e., no scientific evidence) that any chemical consumed in the amount that is present in food has ever caused an injury, illness, or mortality.¹³ Despite this, because we can’t find a way to prove otherwise, the blame-game field of Chemophobia has broadened substantially to include many more human ailments and concerned citizens, activists, and public-safety lawyers/litigators have seized the moment.⁴³  

Innovations in Testing: A Role for Humanized Animal Models? 

But help may be on the way. Biological drug developments are getting an upgrade by using “humanized animal models” (HAMs). Human-specific protein-receptor (HSPR) interactions and HAMs are being used in development of new biological therapeutics (i.e., remedies for diseases) rather than depending on anticipated challenges posed by the inadequacy of traditional rodent, canine, and non-human primates in predicting the toxicity of specific chemicals.⁶⁵  Perhaps HAMs could replace laboratory test-animal experiments for predicting the toxicity of the chemicals in our food. 

The Case of Red Dye #3 – An Example of Policy Lag 

On its way out, in January 2025, Biden’s FDA banned red dye #3 using the Delaney Clause and the results of a flawed study that had been conducted in the 1980s.⁶⁶ The FDA admitted that there is no scientific evidence that proves that the dye causes hyperactivity or any other neurobehavioral effects in children, as is claimed by the Center for Science in the Public Interest (CSPI), U.S. congress Members, and the State of California.^67,68 The Delaney Clause needs to be reworded to take into consideration dosage and portion of the diet to replace “any” and “must be banned” in the wording of the Delaney Clause.⁶⁶ If not, it appears likely that the FDA will consider banning many more food additives that are presently allowed on its GRAS list.⁶⁸ 

Regulatory Differences Between the U.S. and Europe 

McDonald’s^TM sells French fries in the U.S. that contain 14 ingredients, while their French fries in Europe contain 3 (potatoes, oil, and salt).⁶⁹ Why? The FDA allows companies to use additives (e.g., TBHQ) that the European Union has banned.⁶⁹ The FDA operates on a reactive model – ingredients are allowed until they are definitively proved dangerous.⁷⁰ 

Policy Shifts on the Horizon 

Prior to the installation of the new administration, Robert F. Kennedy Jr., now the Secretary of DHHS, reportedly said he intended to take a wrecking ball to the Entitlements (e.g., SNAP, WIC), the Dietary Guidelines for Americans, and the FSA’s GRAS list.^71,72,73 

REFERENCES

1. Webster’s New Explorer Dictionary. 1999. Merriam-Webster Inc. Springfield MA.
2. Campbell, Hank. 2018. Food Quality & Safety. November Edition.
3. FDA-USDHHS. 2024. usfda@public.govdelivery.com Accessed on 4/15/2024.
4. FDA-USDHHS. 2024. usfda@public.govdelivery.com Accessed on 4/3/2024.
5. Hetter, Katia. 2024. CNN. May 11 Issue.
6. Schulz, Claudia. 2012. Food Quality. March Edition.
7. Smith, G. and K. Belk. 2025. Certified Group FSNS Newsletter. February Edition.
8. Carroll, Vincent. 1991. Rocky Mountain News. January 27 Issue.
9. Campbell, Hank. 2018. Food Quality & Safety. November Edition.
10. Stier, Richard. 2018. Food Quality & Safety. July Edition.
11. National Academy of Sciences. 1987. Press Release on 9/12/1987.
12. Scheuplein et. al. 1990. Food and Drug Administration. May 15 Issue.
13. Ames, Bruce. 1991. University of California-Berkeley. January 27 Issue.
14. Smith, Gary. 1992. Colorado State University. February 11 Issue.
15. LaMotle, Sandee. 2020. CNN. September 23 Issue.
16. Tilley, Caitlin. 2024. Dailymail.com. Accessed on 4/26/2024.
17. Parker, Laura. 2023. National Geographic. May 13 Issue.
18. Winters, Joseph. 2024. The Grist. May 20 Issue.
19. Grey, Jaina. 2024. Wired. April 22 Issue.
20. Dhanesha, Neal. 2022. VOX. May 6 Issue.
21. Leslie et al. 2022. Environmental International. 13:58-67.
22. Duchorme, Jamie. 2024. TIME. May 9 Issue.
23. University of Florida. 2023. Food Animal Residue Avoidance Database. December 15 Issue.
24. Shike, Jennifer. 2024. PORK. May 20 Issue.
25. Johnston, Tom. 2019. Meatingplace. December 16 Issue.
26. McKie, Robin. 2024. The Guardian. May 25 Issue.
27. Henderson, Bailee. 2024. Food Safety Magazine. March 6 Issue.
28. Laca, Anna-Lisa. 2019. Milk Business. November 4 Issue.
29. Smith, Gary. 2024. Texas A&M University. April 10 Issue.
30. Erpelding, Dennis. 2015. FSNS Newsletter. December Edition.
31. FDA-USDHHS. 2022. usfda@public.govdelivery.com. Accessed on 7/6/2022.
32. Environmental Working Group. 2020. The Packer. July 22 Issue.
33. Bendix, Aria. 2024. NBC News. April 10 Issue.
34. Reuters. 2021. Press Release. August 16 Issue.
35. Welsh et al. 2024. Food Safety Magazine. May Edition.
36. Rentschler and Lenova. 2022. World Bank Blogs. May 18 Issue.
37. Orr et al. 2024. Genetic Engineering News. July 5 Issue.
38. EPA. 2024. www.epa.gov/safepestcontrol. Accessed on 8/12/2024.
39. Boyette et al. 2023. CNN. October 12 Issue.
40. Gabriel, Jesse. 2024. Food Safety Magazine. March 18 Issue.
41. FDA-USDHHS. 2024. http:www.fda.gov/Food/Chemicals-Metals-Pesticides. Accessed on 8/10/2024.
42. Scott, Chris. 2024. Meatingplace. March 11 Issue.
43. Scott, Dylan. 2024. VOX. April 8 Issue.
44. Prepared Foods. 2014. Press Release. June Edition.
45. European Food Safety Authority. 2024. Food Safety Magazine. May 28 Issue.
46. Clayton, Chris. 2017. Progressive Farmer. Winter Edition.
47. Henderson, Bailee. 2024. Food Safety Magazine. March 19 Issue.
48. Joshu, Emily. 2024 Daily Mail. May 10 Issue.
49. Horn-Muller, Agurella. 2024. National Geographic. February 10 Issue.
50. Brooks, Rhonda. 2024. AG·WEB. February 7 Issue.
51. Eckelkamp, Margy. 2024. The Daily Scoop. May 9 Issue.
52. FDA-USDHHS. 2024. usfda@public.govdelivery.com. Accessed on 5/17/2024.
53. FDA-USDHHS. 2023. usfda@public.govdelivery.com. Accessed on 11/14/2023.
54. Surak, John. 2024. Food Safety Magazine. May Edition.
55. EPA. 2024. http://www.epa.gov/safepestcontrol. Accessed on 6/23/2024.
56. Morgan, Clair. 2024. Food Safety Magazine. July 2 Issue.
57. Dorland’s Illustrated Dictionary. 1988. W.B. Saunders Company. Philadelphia PA.
58. Arecella et al. 2016. EFSA Journal. August 31 Issue.
59. Surak, John. 2024. Food Safety Magazine. May Edition.
60. Fauci, Anthony. 2024. CSPAN June 3 Issue.
61. Gerstein et al. 2019. The Lancet. January 19 Issue.
62. Teicholz, Nina. 2014. The Big Fat Surprise. Simon & Schuster. New York NY.
63. Willett, Walter. 2024. Harvard University. July 31 Issue.
64. Safe, Stephen. 2020. Texas A&M University. June 2 Issue.
65. Rose, Aaron. 2024. Genetic Engineering News. May 15 Issue.
66. Brashears, Mindy. 2025. Meatingplace. February 3 Issue.
67. Henderson, Bailee. 2024. Food Safety Magazine. September 23 Issue.
68. Jones, Jim. 2025. Food Safety Magazine. January 15 Issue.
69. Watters, Jesse. 2024. Fox News. February 7 Issue.
70. Boom, Gregory. 2024. Meatingplace. October 3 Issue.
71. Wiesemeyer, Jim. 2024. Pork Business. November 14 Issue.
72. Brueck, Hilary. 2024. Business Insider. November 14 Issue.
73. Ingraham, Laura. 2024. Fox News. November 14 Issue.
74. FDA Human Foods Program, 2025, at: https://www.fda.gov/food, accessed May 21, 2025.