Exposure to air pollution is considered an important external stressor for hair, which can cause damage to the cuticles (higher wet/dry combing energy), protein degradation, and a more hydrophilic hair surface.

Compared to leave-on products, rinse-off products, such as shampoo, is much more challenging to  deliver the anti-pollution benefit due to the surfactants and rinse process during hair washing. A recently developed conditioning and deposition mechanism was found to be effective in pollution protection of hair from a rinse off product. The hair tresses, washed with a silicone-free shampoo containing 0.2 wt.% acrylamidopropyltrimonium chloride/acrylamide copolymer (APTAC/ACM), showed, after the first wash, a 3-fold decrease of protein degradation after smoke exposure, as compared to no effect for the shampoos with 0.2 wt.% of  conventional conditioning polymers polyquaternium 10 or cationic guar, or untreated tresses. Almost no protein degradation by smoke was seen after a second wash. Furthermore, the tresses, washed with APTAC/ACM containing shampoo, also demonstrated anti-dust deposition benefit.