A Palette of Peril
How the 19th Century Dyed its Food with Chemical Colors
The Allure of the Artificial
Imagine a time when your green peas might have been colored with copper, your pickles preserved with lead, and your cheese tinted a cheerful orange with red lead.
This was the startling reality of the 19th-century dinner table. As populations migrated to cities during the Industrial Revolution, people became dependent on commercially produced food, often of dubious quality and origin 6 . To make watered-down, spoiled, or inferior products appealing, manufacturers turned to a colorful array of dangerous additives.
The quest for vibrant, cheap food coloring would spark a chemical revolution, leading to profound questions about food safety that still resonate today. This is the story of how a quest for color transformed our food from the ground up, beginning with an accidental discovery in a London laboratory.
Dangerous Additives
Copper, lead, and mercury were common in food
Industrial Revolution
Urbanization changed food production and consumption
Chemical Innovation
Accidental discoveries led to synthetic dyes
The Dismal Dinner Plate: Food Before Synthetic Dyes
Before the 1850s, the quest for colorful food was already a dangerous game. Cookbooks from the Regency period contained explicit instructions for using toxic substances to enhance the appearance of food. A common practice was "greening"—boiling vegetables with coins or verdigris (the blue-green patina on copper) to achieve a brilliant, almost turquoise hue 9 .
Historical Recipe for Green Dye
Historical accounts reveal recipes for green food dye made from a mixture of verdigris, vinegar, alum, and bay salt to be used on "whatever you wish to green" 9 .
"A consumer might ingest 'Armenian bole, red lead, or even bisulphuret of mercury' with their breakfast, and copper with their pickles at dinner." 8
The results were often tragic, with widespread poisonings and even deaths reported 8 .
A Happy Accident: Perkin's Purple and the Dawn of Synthetic Dyes
In 1856, an 18-year-old British chemistry student named William Henry Perkin changed everything. While trying to synthesize quinine, a treatment for malaria, from the abundant by-product of coal processing known as coal tar, Perkin made a mistake 1 .
His experiment yielded a dark, sludgy residue. When he cleaned his flask with alcohol, he was stunned to see it dissolve into a brilliant and enduring purple hue 1 .
Perkin had stumbled upon the world's first synthetic dye, which he named mauveine 8 . He quickly patented his process and started a company to produce the dye. Its popularity was instantaneous; even Queen Victoria was seen wearing a dress dyed with Perkin's synthetic mauve 1 .
Almost overnight, coal tar, a substance previously dumped as waste, became a source of immense wealth and scientific interest 1 .
William Henry Perkin
Discoverer of mauveine, the first synthetic dye, at age 18.
Coal-Tar Colors
Chemists raced to develop new colors from coal tar, creating a whole spectrum of vibrant, stable, and incredibly cheap dyes. These were often known as "coal-tar colors" or "aniline dyes" because they were derived from aniline, which itself came from the benzene in coal tar 1 .
Food Industry Adoption
The food industry was an eager adopter, using these new synthetic dyes in butter, candy, and alcohol 1 . Ironically, these early synthetic dyes were initially seen as a potential improvement over the known poisons they replaced, as their intense color meant only tiny amounts were needed, leaving the food's flavor unaffected 1 .
The Poison Squad: A Grisly Experiment for Food Safety
The wild west of food adulteration could not continue forever. In the United States, a formidable crusader emerged: Dr. Harvey Washington Wiley, the chief chemist of the U.S. Department of Agriculture 6 . Appalled by the unregulated use of chemicals in food, Wiley devised a radical experiment to prove their dangers.
Methodology: Dining with Danger
Recruitment
Volunteers were promised three free, chef-prepared gourmet meals per day, seven days a week.
Control and Experimental Groups
The volunteers were divided into groups. Half would receive meals containing a capsule of a suspected food additive, while the others received a placebo.
Dosing
The additives tested were common industrial chemicals used in food, including formaldehyde (in milk), borax (a cleaning product used as a preservative), and salicylic acid 6 .
Monitoring
The men were forbidden from eating any outside food. Their health was closely monitored for adverse reactions.
Results and Analysis: The Proof was in the Poisoning
The results were as predictable as they were horrifying. Volunteers who ingested the additives became seriously ill 6 . The experiment provided Wiley with the concrete, human data he needed to argue that the unregulated use of such chemicals was harmful to human health.
Public Impact
The Poison Squad became a national sensation, making front-page news and even inspiring popular songs 6 . It captured the public's imagination and created widespread awareness of the perils lurking in their food, building crucial momentum for the passage of landmark food safety legislation.
Regulation and Legacy: From Wild West to Government Oversight
The public outrage fueled by Wiley's experiments and the work of other activists finally led to action. In 1906, the U.S. Congress passed the Pure Food and Drugs Act 5 6 . This law was a turning point, prohibiting the use of poisonous or deleterious colors in confectionery and the coloring of food to conceal damage 5 .
Key Milestones in U.S. Food Dye Regulation
| Year | Legislation | Key Impact |
|---|---|---|
| 1906 | Pure Food and Drugs Act | Established the first positive list of permitted colors, starting with seven synthetic dyes 5 8 . |
| 1938 | Federal Food, Drug, and Cosmetic (FD&C) Act | Made color batch certification mandatory and introduced the FD&C nomenclature 5 . |
| 1960 | Color Additive Amendments | Required that all color additives be deemed "suitable and safe" for their intended use 5 . |
Banned Synthetic Food Dyes
| Color Name | Date of Removal (U.S.) | Reason for Removal |
|---|---|---|
| FD&C Orange No. 1 & 2 | 1950s | Removed after Halloween candy caused numerous illnesses 1 . |
| FD&C Red No. 32 | 1950s | Removed alongside the Orange dyes for causing illness 1 . |
| FD&C Red No. 2 | 1970s | Banned after studies suggested it caused tumors in female rats 1 . |
Conclusion: A Colorful Legacy
The introduction of chemical dyes into food in the 19th century is a story of innovation, deception, and ultimately, responsibility. What began as an accidental discovery in a quest for malaria treatment unleashed a revolution that made food brighter and more appealing but also exposed consumers to unforeseen dangers.
Modern Concerns
Concerns have shifted to potential behavioral effects in children, with a 2022 systematic review concluding that synthetic food dyes are associated with adverse neurobehavioral outcomes in children 7 .
The courageous work of scientists and reformers like Harvey Wiley, who conducted shocking experiments to prove the need for change, paved the way for the food safety laws we often take for granted today. The journey from verdigris-green peas to federally certified colors reflects a larger struggle to balance aesthetic appeal with public health—a challenge that continues as we now scrutinize the very synthetic dyes that were once hailed as a safe alternative.