Summary of the National Toxicology Program Benzidine Dye Initiative

Abstract

The benzidine dye initiative is a research program established by the National Toxicology Program to generate an integrated body of scientific information regarding the potential health risks associated with exposure to benzidine-and benzidine-congener-derived dyes. Because an indepth evaluation of each of the hundreds of benzidine-congener-derived dyes was considered impractical, the research program was designed to study the metabolism and disposition, genetic toxicity, and in vivo toxicity and carcinogenicity of two primary benzidine congeners, 3,3'-dimethylbenzidine and 3,3'-dimethoxybenzidine, and a select group of prototypical dyes derived from those amines. It was anticipated that by applying the basic information generated in these extensive studies, it would be possible to make regulatory decisions about other dyes after conducting only a minimal number of experiments such as studies of disposition and metabolism, and in vitro mutagenicity. This paper summarizes the results of studies conducted to evaluate the metabolism, disposition, mutagenicity, toxicity, and carcinogenicity of representative benzidine congeners and derived dyes. -Environ Health Perspect 102(Suppl 2): 63-78 (1994).

Influence of the organic loading rate on the hydraulic behaviour and the azo‐dye removal in an anaerobic filter

“…Some azo dyes are not normally toxic but the amines resulting from the anaerobic digestion of these substances may possess these characteristics . Some authors have found that the cleavage of azo bonds in benzidine based azo dyes or direct dyes produce benzidine and 4‐aminobiphenyl which are classified as carcinogenic and mutagenic . Table presents studies of the degradation of different direct dyes and their by‐products in reactors with different configurations.…”

Dosage de l’hémoglobine urinaire par un réactif au 3,3’-diméthylbenzidine : Mise au point technique

“…La mesure de la teneur en hémoglobine dans ces milieux biologiques relève de plusieurs techniques : spectrophotométrie directe (Wians et al, 1988), spectrophotométrie dérivée (Taulier et al, 1986 ;Copeland et al, 1989), chimiluminescence (Olsson et al, 1982), turbidimétrie (Engler et al, 1979) et colorimétrie (Ahlquist et Schwartz, 1975 ;Slaunwhite et al, 1979 ;Fairbanks et al, 1992). Les méthodes colorimétriques, plus usuelles, se font sur le plasma et mettent à profit l'activité peroxydasique de l'hémoglobine qui oxyde un chromogène (Fairbanks et al, 1992 ;Morgan et al, 1994;Dionne, 2006). La benzidine, premier chromogène utilisé s'est révélée cancérigène (Kum-Tatt et Ling, 1969 ;Morgan et al, 1994 ) ; elle a été alors remplacée par ses dérivés qui le sont moins comme l'attestent plusieurs études (Lijana et Williams, 1979 ;Levinson et Goldman, 1982 ;Pillier-Loriette et al, 1983 ;Takayanagi et Yashiro, 1984).…”

“…Les méthodes colorimétriques, plus usuelles, se font sur le plasma et mettent à profit l'activité peroxydasique de l'hémoglobine qui oxyde un chromogène (Fairbanks et al, 1992 ;Morgan et al, 1994;Dionne, 2006). La benzidine, premier chromogène utilisé s'est révélée cancérigène (Kum-Tatt et Ling, 1969 ;Morgan et al, 1994 ) ; elle a été alors remplacée par ses dérivés qui le sont moins comme l'attestent plusieurs études (Lijana et Williams, 1979 ;Levinson et Goldman, 1982 ;Pillier-Loriette et al, 1983 ;Takayanagi et Yashiro, 1984).…”

Detection of gentoxicity of benzidine and its derivatives with the Escherichia coli DJ 702 lacZ reversion mutagenicity assay

“…Benzidine has been used for the production of azo dyes, which are widely applied in the textile, paper, and leather industries (Morgan et al. 1994; Chung et al.…”