Continuous discharge of lignin containing colored wastewater from pulp paper mill into the environment has resulted in building up their high level in various terrestrial and aquatic systems.
May I know what model organism you are referring to? Organisms in the ecosystem polluted with Kraft lignin would have gradually developed tolerance to them. I am on the lookout for the threshold level of Kraft lignin (ppm) concentration in polluted ponds as well. I remember reading an article which reported the presence of around 2g/L lignin content in a contaminated pond.