What helps me is breath meditation.<p>I sit down, if possible in the circumstances, and begin paying attention to my breath.<p>I pay attention to it the same way I would pay attention to the tip of the paintbrush as I am painting.<p>I do this for several seconds or minutes at a time, until I'm able to achieve a calm state.<p>Sometimes I do it counting the breaths, which may work well with your attention specifics.<p>Remember that you are experiencing evolved behaviors and states which are being triggered in unproductive ways.<p>You can change these triggers by first dissipating their effects. This is what breath meditation did for me, over the course of several years.
I knew someone who benefited from taking extra vitamins and resolving mold issues in their home. It didn't cure it, but it made it vastly more manageable.
I'm not a doctor (obviously) but, as I understand, the solution to OCD is not to give in to your compulsions. Suffer through your discomfort and anxiety without performing any actions to control your discomfort and anxiety. Treat your compulsions as your enemy rather than your unpleasant internal states.
If you learn to engineer your interior the way you want it to be, i.e. your thoughts and emotions OCD will not be that big of an issue to handle. I'd recommend taking the Inner Engineering program online. It has done wonders for me and millions across the world. Visit: innerengineering.com
Please seek professional advice if you haven't already. Advice from strangers on the internet can sound comforting but it won't do much for serious problems that are also very personal.