Dishwashing liquid

Dishwashing liquid (washing-up liquid or fairy liquid in British English), also known as dishwashing soap, dish detergent, or dish soap, is a type of detergent used in dishwashing. It is usually a highly-foamy mixture of surfactants with low skin irritation that consumers primarily use for washing glasses, plates, cutlery, and cooking utensils. In addition to its primary use, dishwashing liquid is also used for various informal applications, like creating bubbles, clothes washing, and cleaning off wildlife affected by oil spills. Dishwashing detergent for dishwashers is also available in various other forms such as cartridges, gels, packs, powder, and tablets.^[1]

Dishwashing liquid in use

Dishwashing liquid with different dyes/scents

Dishwashing liquid has been in use for a long time in various compositions and under different usage conditions.^[2][3][4] Most modern dishwashing liquids function best with hot water. However, there are some special dishwashing liquids designed to work well with cold water or seawater.

History

Main article: Detergent

Before the invention of detergents in Germany during World War I,^[4] consumers used washing soda for dishwashing.^[2][3] Liquid detergent manufacturing for dishwashing began in the middle of the 20th century. Dishwashing detergent production started in the United States in the 1930s–1940s.^[4][5] Teepol, the first dishwashing detergent in Europe, began its production in 1942.^[6]

Composition

Dishwashing liquid may contain bleach, enzymes, and rinsing aids.^[1] The main ingredient is water and the main active ingredients are detergents. Dishwashing liquid uses detergent instead of soap because the soaps are likely to react with minerals in the water to form soap scum. Dishwashing liquids also use thickening and stabilizing agents.^[7] Other ingredients may include hydrotropes, salts, preservatives, fragrances, antibacterial ingredients, and dyes. Preservatives prevent the proliferation of microorganisms within the liquid. Antibacterial ingredients make it difficult for bacteria to survive on surfaces.^[5]

Some alternatives for dishwashing detergents may be homemade, using ingredients such as borax, essential oil, eucalyptus oil, leftover cooking oil, and bar soap, among others.^[8][9]

Water and dishwashing liquid mixing to form foam

Items that can be damaged by certain dishwashing liquids (especially with the use of hot water or when put into a dishwasher) include household silver, fine glassware, gold-leafed objects, disposable plastics, as well as objects made of brass, bronze, cast iron, pewter, tin, or wood.^[1] Dishwashing liquid components are also harder to rinse off from rough surfaces than smooth surfaces, increasing the chance of accidental ingestion.^[10]

Hand dishwashing detergents utilize surfactants to play the primary role in cleaning.^[5] The reduced surface tension of water and increased solubility of modern surfactant mixtures allow water to run off dishes very quickly. Additionally, surfactants remove grease and food particles to aid in cleaning dishes, and may also provide foam.^[5]

Surfactant design

There have been comparisons of different surfactants that reduce the surface tension of water to determine the most efficient dishwashing liquid.^[11][12] Lowering of surface tension helps with the cleaning processes.^[11] A study showed that anionic surfactant combined with non-ionic surfactant worked better than other combinations.^[11] Another study found that cationic and anionic surfactants combined worked better than non-ionic and anionic surfactants combined.^[11][12] Anionic and amphoteric surfactants combined are the least effective out of the three.^[11][12]

Safety concerns

In 2010, the United States FDA raised health concerns over triclosan, an antibacterial substance used in some dish liquids.^[13] Elsewhere, triclosan has been found to create problems at wastewater treatment plants, whereby it can "sabotage some sludge-processing microbes and promote drug resistance in others."^[14] As of 2025, triclosan has been banned in the United States, the European Union, Canada, and Australia, among others.^[15]

Some dishwashing products contain phosphates. Phosphates make dishes cleaner but can also cause harmful algal bloom as the wastewater goes back to the natural environment.^[16] Because of this, many places have banned this component.^[16] Phosphates can also cause harmful health effects upon skin contact.^[5]

Many dishwashing liquids contain perfume which can cause irritant or allergic contact dermatitis.^[17] It can also cause hand eczema. Those with sensitive skin are recommended to use hypoallergenic gloves to avoid direct contact with the liquids.^[18] Surfactants that are anionic showed promising results in preventing skin irritation.^[19]

Primary uses

Dishwashing liquid is primarily used for removing food stains and grease from dirty dishes and tableware.^[1][5] Consumers usually scrape heavy soil (large food particles) from the dishes before applying the dishwashing liquid.^[1]

Hand dishwashing

Dishwashing process

Consumers handwash dishes in the absence of a dishwashing machine or when large "hard-to-clean" items are present.^[5]

Automatic dishwashing

Automatic dishwashing is when consumers use a dishwasher or other apparatus.^[5] It is generally preferred for convenience, sanitation, or personal preference.^[5] The cleaning is less reliant on the detergent's surfactants and more so on the machine's hot water as well as the detergent's builders, bleach, and enzymes.^[5] Automatic dishwashing detergents' surfactants generally have less foam to avoid disrupting the machine.^[5]

Other uses

Domestic Usage

Reader's Digest notes that dishwashing liquid may be used to kill ants and weeds, help spread water-borne fertilizer, and wash human hair.^[20]Good Housekeeping suggests using it to attract and drown fruit flies by mixing with vinegar. ^[21] Oregon State University's Cooperative Extension Service notes the use of dishwashing liquid to get rid of spider mites.^[22]

Washing an oiled Gannet with dishwashing liquid

Some other uses of dishwashing liquid include:

• Cleaning mirrors and windows.^[23]
• Cleaning delicate clothing fabrics such as hosiery and lingerie.^[24]

• Making decals and vinyl graphics easier to position when applying.^[25][26]
• Making homemade garden pest deterrents.
• Removing coffee, tea, olive oil, soda and fruit juice stains from fabrics.^[27][28]

Industrial Usage

Dishwashing liquid for inspecting equipment under pressure for leaks, such as propane fittings.^[29][30] It can also be used for inspecting pneumatic tires for flats, as well as for quality assurance during the installation process, and as a mounting bead lubricant.^[31][32][22] Dishwashing liquid can also treat birds in oil spills.^[33][34]

Market share

Currently, market research companies like Euromonitor and Grand View Research collect data on different brands' market share.^[35][36]

Euromonitor International collects market trends of many big brands like Procter and Gamble, Colgate-Palmolive, Henkel, Reckitt Benckiser, Unilever, Ajax.^[35]

For example, according to Euromonitor International, in 2013, Reckitt Benckiser held the highest retail value share percentages in nine countries:^[35] Italy (31%), Spain (29%); with the Finish brand: Australia (38%), New Zealand (38%), Austria (32%), Ireland (29%), and Israel (27%); Denmark (30%) with the Neophos brand; and Portugal (22%) with the Calgonit brand.

As of 2025, the global dishwashing liquids market is approximately valued at US$18 billion.^[37]

See also

• Dishwasher detergent
• Cleaning agent
  • List of cleaning agents
  • List of cleaning products
• Soap
• Green cleaning
• Washing