Commercial and Industrial Use
PABA mainly finds use in the biomedical sector. Other uses include its conversion to specialty azo dyes and crosslinking agents.
In the past, PABA was widely used in sunscreens as a UV filter. It is a UVB absorber, meaning that it can absorb wavelengths between 290-320 nm. Patented in 1943, PABA was one of the first active ingredients to be used in sunscreen. The first in vivo studies on mice showed that PABA reduced UV damage. In addition, PABA was shown to protect against skin tumors in rodents. Animal and in vitro studies in the early 1980s suggested PABA might increase the risk of cellular UV damage. On the basis of these studies as well as problems with allergies and clothing discoloration, PABA fell out of favor as a sunscreen. However, water-insoluble PABA derivatives such as padimate O are currently used in some products.
Read more about this topic: 4-Aminobenzoic Acid
Famous quotes containing the words commercial and/or industrial:
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—Oscar Wilde (1854–1900)
“A few ideas seem to be agreed upon. Help none but those who help themselves. Educate only at schools which provide in some form for industrial education. These two points should be insisted upon. Let the normal instruction be that men must earn their own living, and that by the labor of their hands as far as may be. This is the gospel of salvation for the colored man. Let the labor not be servile, but in manly occupations like that of the carpenter, the farmer, and the blacksmith.”
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