Thirty-one fluorescent whitening agents (FWAs) that were considered for use in laundry products have been patch tested for skin-sensitizing potential. Test exposures were highly exaggerated over those anticipated for consumers.
Three of the products tested produced delayed contact hypersensitivity under the test conditions, and they were accordingly rejected for consideration as detergent components. The sensitizing potential of two of these materials was tentatively attributed to a single chemical species that was present in both products.
The other 28 of the materials tested gave negative test results and were judged to be very unlikely to cause dermatitis under practical usage conditions. For some of the materials, this prediction of safety has been validated by extensive market experience. All of the FWAs tested are identified by chemical names and structures.
Griffith JF. Fluorescent Whitening AgentsTests for Skin-Sensitizing Potential. Arch Dermatol. 1973;107(5):728-733. doi:10.1001/archderm.1973.01620200046011