A compilation of genotoxicity and carcinogenicity data on aromatic aminosulphonic acids.

A review is presented to evaluate existing information on genotoxicity and carcinogenicity testing of various aromatic aminosulphonic acids (AASAs). A great variety of water-soluble azo dyes can form aromatic phenyl- or naphthyl-aminosulphonic acids by chemical and enzymatic reduction. AASAs are also used as intermediates in the synthesis of azo dyes and azo pigments and can arise as contaminants in the final products.

The limits of bioaccumulation of organic pigments in fish: their relation to the partition coefficient and the solubility in water and octanol.

A reliable experimental determination of the partition coefficient Pow of organic pigments is met with serious difficulties due to the extremely low water solubilities of these compounds. Therefore, the Pow values and the water solubilities were calculated for 11 typical organic pigments and some disperse dyes as well. The calculated Pow values of the pigments were very high predicting bioaccumulation factors (BF) several orders of magnitude above 100.

Color chemistry and the environment.

Dyes, and by extension the various organic compounds used for coloration, including organic pigments and fluorescent whitening agents (FWAs), are among the organic chemicals which we encounter as technological and functional necessities in nearly every sphere of our daily lives. They also greatly influence our mood and thus contribute enormously to the very quality of the lives we lead. At the same time we have come to realize that our achievements and continuing technological progress are only worthwhile provided they pose no hazard to the environment.

History of whitening.

Man's earliest endeavours to enhance the brightness of white objects in everyday use, especially clothing, led to the invention of various bleaching processes. KRAIS'S discovery in 1929 that the natural substance esculin could be applied to textiles to give whites of unprecedented brilliance led to the industrial development of fluorescent whitening agents (FWA's). The limited effectiveness of esculin, a glycoside of 6,7-dihydroxycoumarin prompted research which led to the synthesis of other compounds of the same class, many of which have proved useful as whiteners; though the really broad developments of the 1940's stemmed from the synthesis of the 4,4'-diaminostilbene-2,2'disulfonic acid derivatives which are sill the most important groups of FWAs.