An adulterant is a substance found within other substances (e.g. food, beverages, fuels), although not allowed for legal or other reasons. The addition of adulterants is called adulteration. An adulterant is distinct from, for example, permitted food additives. There can be a fine line between adulterant and additive; chicory may be added to coffee to reduce the cost—this is adulteration if not declared, but may be stated on the label. The term "contamination" is usually used for the inclusion of unwanted substances due to accident or negligence rather than intent.
Adulterants added to reduce the amount of expensive product in illicit drugs are called cutting agents. Deliberate addition of toxic adulterants to food or other products for human consumption is poisoning.
In food and beverages
Past and present examples of adulteration, some dangerous, include:
- Roasted chicory roots used as an adulterant for coffee
- Diethylene glycol, used dangerously by some winemakers in sweet wines
- Apple jellies (jams), as substitutes for more expensive fruit jellies, with added colorant and sometimes even specks of wood that simulate raspberry or strawberry seeds
- Water, for diluting milk and alcoholic beverages
- Cutting agents used to adulterate (or "cut") illicit drugs—for example, shoe polish in hashish, amphetamines in ecstasy, lactose in cocaine
- Urea, melamine and other nonprotein nitrogen sources, added to protein products to inflate crude protein content measurements
- High fructose corn syrup or cane sugar, used to adulterate honey
- Water or brine injected into chicken, pork, or other meats to increase their weight
Historically, the use of adulterants has been common; sometimes dangerous substances have been used. In the United Kingdom during the Victorian era, adulterants were common; for example, cheeses were sometimes colored with lead. Similar adulteration issues were seen in industry in the United States, during the 19th century. There is dispute over whether these practices declined primarily due to government regulation or to increased public awareness and concern over the practices. In the early 21st century, cases of dangerous adulteration occurred in the People's Republic of China.
Adulterant use was first investigated in 1820 by the German chemist Frederick Accum, who identified many toxic metal colorings in food and drink. His work antagonized food suppliers, and he was ultimately discredited by a scandal over his alleged mutilation of books of the Royal Institution library. The physician Arthur Hill Hassall conducted extensive studies in the early 1850s, which were published in The Lancet and led to the 1860 Food Adulteration Act and other legislation.
At the turn of the 20th century, industrialization in the United States led to a rise in adulteration which inspired some protest. Accounts of adulteration led the New York Evening Post to parody:
Mary had a little lamb,
And when she saw it sicken,And now it's labeled chicken.
She shipped it off to Packingtown,
However, even in the 18th century, people complained about adulteration in food:
"The bread I eat in London is a deleterious paste, mixed up with chalk, alum and bone ashes, insipid to the taste and destructive to the constitution. The good people are not ignorant of this adulteration; but they prefer it to wholesome bread, because it is whiter than the meal of corn [wheat]. Thus they sacrifice their taste and their health. . . to a most absurd gratification of a misjudged eye; and the miller or the baker is obliged to poison them and their families, in order to live by his profession." – Tobias Smollet, The Expedition of Humphrey Clinker (1771)
A history of food poisoning and adulteration is given in the textbook, Death in the Pot: The Impact of Food Poisoning on History.
In drug tests
Adulterants can be added to urine to interfere with the accuracy of drug tests. These adulterants are often oxidative in nature—hydrogen peroxide and bleach have been used, sometimes with pH-adjusting substances like vinegar or sodium bicarbonate. These can be detected by drug testing labs, but some less expensive tests do not look for them.
Incidents of adulteration
- In 1987, Beech-Nut was fined for violating the US Federal Food, Drug, and Cosmetic Act by selling flavored sugar water as apple juice.
- In 1997, ConAgra Foods illegally sprayed water on stored grain to increase its weight.
- In 2007, samples of wheat gluten mixed with melamine, presumably to produce inflated results from tests for protein content, were discovered in the USA. They were found to have come from China. (See: Chinese protein adulteration.)
- In 2008, significant portions of China's milk supply were found to have been adulterated with melamine. Infant formula produced from this milk killed at least six children and is believed to have harmed thousands of others. (See: 2008 Chinese milk scandal.)
- In 2012, a study in India across 29 states and union territories found that milk was adulterated with detergent, fat, and even urea, and diluted with water. Just 31.5% of samples conformed to FSSAI standards.
- In the 2013 meat adulteration scandal in Europe, horsemeat was passed off as beef.
- Surrogate alcohol: harmful substances which are used as substitutes for alcoholic beverages
- Denatured alcohol: alcohol which is deliberately poisoned to discourage its recreational use
- Weise, Elizabeth (April 24, 2007). "Food tests promise tough task for FDA". USA Today. Retrieved 2007-04-29.
- Burros, Marian (2006-08-09). "The Customer Wants a Juicy Steak? Just Add Water". The New York Times.
- The fight against food adulteration, Noel G Coley, RSC, Education in Chemistry, Issues, Mar 2005
- Jeffrey M. Pilcher, Food in World History New York: Routledge, 2006, p. 59
- Weston A.Price: Against the Grain, Section Bread to Feed the Masses
- Satin, Morton, Death in the Pot: The Impact of Food Poisoning on History, 262 pages, Prometheus Books, (2007), ISBN 1-59102-514-1 
- Juiceless baby juice leads to full-length justice|FDA Consumer
- ConAgra Set to Settle Criminal Charges It Increased Weight and Value of Grain – New York Times
- Sinha, Kounteya (10 January 2012). "70% of milk in Delhi, country is adulterated". Times of India. Retrieved 23 February 2014.