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Assessing and Managing Chemicals under TSCA

Risk Management for Benzidine Dyes

What are benzidine dyes?

Benzidine and its congeners are important precursors in the synthesis of dyes. Benzidine's congeners, 3,3'-dichlorobenzidine, 3,3'-dimethylbenzidine, and 3,3'-dimethoxybenzidine and dyes metabolized to the latter two congeners have all been classified as "reasonably anticipated to be human carcinogens.

Where benzidine dyes are found?

Benzidine-based and congener-based dyes are used in the production of textiles, paints, printing inks, paper, and pharmaceuticals. These dyes have the potential to be leached from textiles, such as clothing, that are in prolonged contact with human skin. They are also used as reagents and biological stains in laboratories, are used in the food industries, and have more recent uses in laser, liquid crystal displays, ink-jet printers, and electro-optical devices.

Why is EPA concerned?

EPA is concerned about the potential risk from exposure, including exposure of children, from using products containing benzidine and congener-based dyes because these dyes have the potential to metabolize to carcinogenic amines both in and on the human body.

What EPA is doing?