A chemometric approach to understanding the bioelimination of anionic, water‐soluble dyes by a biomass—Part 3: Direct dyes**

Using a new, rapid and robust laboratory method for assessing the bioelimination of water‐soluble dyes, the level of bioelimination of a series of direct dyes has been determined and a chemometric analysis has been conducted on the bioelimination results to correlate bioelimination with chemical structure. Bioelimination varies from 0 to 95% and correlates, for the majority of the direct dyes studied, with their size/charge ratio. The bioelimination of direct dyes is enhanced by large size/charge ratios, the presence of aromatic amino functions and extended azo (naphthalene) chromophores.