Molecular Engineering of Sustainable Synthetic Colorants

摘要

While the fastness properties of synthetic dyes are essential to their commercial utility, the need to avoid harming human health and the environment is an important requirement in the commercial use of technically viable synthetic dyes and their auxiliary chemicals. For textile dyes, safety is often demonstrated by conducting tests involving ecotoxicity and genotoxicity (e.g. mutagenicity and carcinogenicity) and aquatic toxicity. The genotoxicity of synthetic dyes became a matter of concern when it was discovered that certain azo dye precursors were human carcinogens. This outcome led to extensive testing of azo dyes and their aromatic amine precursors for mutagenic and/or carcinogenic potential. Although those studies were aimed mainly at risk assessment and product regulation, the utility of the resultant data for the design of alternatives to environmentally unfriendly compounds was also examined. The present paper provides an overview of studies pertaining to the environmental chemistry of azo dyes, by far the major class of textile dyes. Specifically, a summary of studies conducted largely in our laboratory since the inception of the dye chemistry program more than 25 years ago is presented. Covered are studies pertaining to the design of textile dyes that pose low risk to human health and the environment, with emphasis on identifying potential alternatives to dyes and dye intermediates that raised genotoxicity or aquatic toxicity concerns.