Reactive dyes toxicity

FLUOROTRIAZINES Riag-fluoriaated triaziaes are used ia fiber-reactive dyes. Perfluoroalkyl triaziaes are offered commercially as mass spectral markers and have been iatensively evaluated for elastomer and hydraulic fluid appHcations. Physical properties of representative fluorotriaziaes are listed ia Table 13. Toxicity data are available. For cyanuric fluoride, LD g =3.1 ppm for 4 h (iahalatioa, rat) and 160 mg/kg (skin, rabbit) (127). 

C.I. Reactive B lack 5, an important type of reactive dye, was comprehensively studied for its toxicological and ecological profile. It proved to be of low acute toxicity and is nonirritant, a weak sensitizer, and has no genotoxic potential. Even in its hydrolyzed form it is not hazardous to the effluent water [4],... 

Another approach for removing reactive dye hydrolysates from the fibre and from the wash water (decolourised waste water) is the use of peroxidases (oxidative active enzymes such as Baylase RP). This multipurpose enzymatic rinse process saves time, energy and water but it is restricted mainly to jet applications. The question of the potential toxicity of the resulting aromatic nitro-compounds (cleavage products of the reactive azoic dyes) has to be resolved. 

Peroxidases Used as an enzymatic rinse process after reactive dyeing, oxidative splitting of hydrolysed reactive dyes on the fibre and in the liquor, providing better wet fastness, decolourised waste water and potentially toxic decomposition compounds (aromatic nitro-compounds)... 

Moore, S. B. 1993. Low toxicity, biodegradable salt substitute for dyeing textiles magnesium acetate in direct or reactive dyeing of cotton. USA Patent Application. 

Once the dyeing cycle is complete, the CO is gasified to recover the excess dye. Unburdened, the clean CO cycles back into the dyeing vessel for reuse, a manoeuvre that saves energy, water, and the heavy metals that comprise much of the toxic runoff into our planet s polluted waterways, according to DyeCoo. The process isn t without its limitations, however. DyeCoo is currently only able to dye scoured (or prewashed) polyester fabric, although the company notes that it s working on a version that will dye unscoured fabric, as well as reactive dyes for cellulosie textiles made from plants. 

In a series of papers (175) comparing chlorination and o2oni2ation, reactive and acid dyes were readily destroyed, but direct and disperse dyes reacted more slowly o2one was more effective in some instances. Although chlorination is cheaper than o2oni2ation, the possible formation of chlorinated compounds such as dioxin and its environmental impact caimotbe overlooked (see Chlorocarbonsandchlorohydrocarbons, TOXIC AROMATICS). 

Gottlieb A, Shaw C, Smith A et al (2003) The toxicity of textile reactive azo dyes after hydrolysis and decolourisation. J Biotechnol 101(l) 49-56... 

An inverse relation between the efficiency of decolorization and the dye concentration has frequently been observed. This fact can be ascribed to several factors, the main of which can be considered the toxicity of the dyes at higher concentrations [41, 45, 51-53]. With Reactive Red 3B-A, concentrations from 100 to 2,000 ppm were tested with C. bifermentans [5]. At concentrations less than 200 ppm, 90% decolorization within 12 h was observed, while at very high dye concentration (>1,000 ppm), the decolorization rate decreased. Khalid et al. [54] observed an inverse relationship between the velocity of the decolorization reaction and the dye concentrations between 100 and 500 mg L 1 azo dye (Reactive Black 5, Direct Red 81, Acid Red 88, and Disperse Orange 3) by Shewanella putrefaciens. A decrease in decolorization percentage at a Acid Black 210 initial concentration growing from 100 to 400 ppm was also observed with V. harveyi, but the decrease was low [44]. 

FIGURE 7.8 Production of reactive oxygen intermediates by activated macrophages. Cells isolated from the livers of control (CTL) or toxicant (TOX)-treated mice were incubated with phorbol myristate acetate for 15 minutes at 37°C, followed by the indicator dye, DCFH-DA. After 15 minutes, the cells were analyzed for green fluorescence by flow cytometry on a Coulter Cytomics FC500 flow cytometer (Beckman Coulter). For each analysis, at least 10,000 events were collected and analyzed using CXP software. 

B. -Y. Chen, Understanding decolorization characteristics of reactive azo dyes by Pseudomonas luteola toxicity and kinetics. Proc. Biochem., 38 (2002) 437 446. 

There are specific fiuorescent dyes for specific pathologies created by specific drug classes, such as phospholipidosis from cationic amphiphilic drugs [18, 19], mitochondrial DNA depletion by nucleoside reverse transcriptase inhibitors that also inhibit mitochondrial DNA polymerase gamma and redox cyclers that produce reactive oxygen species. The complex mechanism of statin-induced toxicity is demonstrated vith early sublethal effects on apoptosis, mitochondrial function and calcium homeostasis [20]. 

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