Polysorbate 80

Chemistry

Polysorbate 80 is derived from polyethoxylated sorbitan and oleic acid. The hydrophilic groups in this compound are polyethers also known as polyoxyethylene groups, which are polymers of ethylene oxide. In the nomenclature of polysorbates, the numeric designation following polysorbate refers to the lipophilic group, in this case the oleic acid (see polysorbate for more detail).

The full chemical names for polysorbate 80 are:

The critical micelle concentration of polysorbate 80 in pure water is reported as 0.012 mM.

Other names

E number: E433

Brand names:

Food use

Polysorbate 80 is used as an emulsifier in foods.

For example, in ice cream, polysorbate is added up to 0.5% (v/v) concentration to make the ice cream smoother and easier to handle, as well as increasing its resistance to melting. Adding this substance prevents milk proteins from completely coating the fat droplets. This allows them to join together in chains and nets, which hold air in the mixture, and provide a firmer texture that holds its shape as the ice cream melts.

Health and beauty use

Polysorbate 80 is also used as a surfactant in soaps and cosmetics (including eyedrops), or a solubilizer such as in a mouthwash. The cosmetic grade of polysorbate 80 may have more impurities than the food grade.

Medical use

Polysorbate 80 is an excipient that is used to stabilize aqueous formulations of medications for parenteral administration, and used as an emulsifier in the manufacture of the popular antiarrhythmic amiodarone. It is also used as an excipient in some European and Canadian influenza vaccines. Influenza vaccines contain 25 μg of polysorbate 80 per dose. It is also used in the culture of Mycobacterium tuberculosis in Middlebrook 7H9 broth. It is also used as an emulsifier in the estrogen-regulating drug Estrasorb.

Laboratory use

Some mycobacteria contain a type of lipase (enzyme that breaks up lipid molecules); when these species are added to a mixture of polysorbate 80 and phenol red, they cause the solution to change color, so this is used as a test to identify the phenotype of a strain or isolate.

Consumption and potential effects

In Europe and America, people eat about 100 mg of polysorbate 80 in foods per day on average. Polysorbate 80 has not been found to be carcinogenic. Rats fed with diets containing up to 5% polysorbate 80 by volume for 12 weeks showed no toxic effects. A 1997 study on two rats looked at the effect of consuming three doses by body weight of 0.5%/day on the sex organs of female rats and saw no abnormal changes in uterine weight. In general, polysorbate 80 is safe and well tolerated, notwithstanding the items listed below.

Crohn's disease

A small number of people may be sensitive to polysorbate 80, and it may be harmful to people with Crohn's disease.

Lowered body weight of offspring

A 2008 animal study concluded no observable adverse effects were seen at doses per body weight up to 1.85 ml/kg·day, which is equivalent to a 70 kg person consuming about 140 g of this substance per day for 21 days. However, administration of 16.783 ml/kg·day to pregnant rats lowered body weight in male and female offspring. This is equivalent to a person consuming about 1.3 kg of polysorbate 80 per day for 21 days.

Decreased fertility

A 1956 study saw no effect on reproduction in rats during their lifetime at up to 5% of their diet being polysorbate 80. Reproduction decreased at 20% of their diet. A 1993 study raised concerns that polysorbate 80 might decrease fertility in rats.

Impact on mouse gut microbiota

Relatively low concentrations of two commonly used emulsifiers, namely carboxymethylcellulose and Polysorbate-80, induced low-grade inflammation and obesity/metabolic syndrome in wild-type hosts and promoted robust colitis in mice predisposed to this disorder. Use of germ-free mice and fecal transplants indicated that such changes in microbiota were necessary and sufficient for both low-grade inflammation and metabolic syndrome.