The researchers bought 15 brands of cosmetic contact lenses over the Internet. To determine whether the lenses had surface pigments, the researchers did a standard rub-off test to confirm whether the pigments were on the surface or embedded. Most of the brands failed (13 out of 15) the rub-off test meaning that the pigments were on the surface and these brands showed significantly higher bacterial adherence.
The conclusion is that purchasers of cosmetic contact lenses risk bacterial infections unless they make healthy choices for their contact lens wear. Consult your eye doctor before buying contact lenses over the Internet.
Contact Lens & Anterior Eye: The Journal of the British Contact Lens Association
Microbial Adherence to Cosmetic Contact Lenses Cont Lens Anterior Eye 2014 Jan 16;[EPub Ahead of Print], KY Chan, P Cho, M Boost