Should I take preventive measures and use the disavow tool?

I have a real business website and the link profile of the website (about 3000 backlinks) is polluted with low quality links (russian profile links, blog comments,...). At this moment the website is not connect with Google Webmaster Tools.

I'm thinking about using the disavow tool to prevent a penalty in the future.

Good plan or a bad plan?

I don't think that you need to use disavow tool. Are you notice a drop site positions in search results? Or something else?

As long as you don't see any drop in the rankings, you don't need to do anything. Also did you check what anchor's were used on russian profile links? may be some one is trying negative seo on your site.

I wouldn't use the disavow tool until you notice penalties. You might be paranoid. Just start building positive signals and keep close tabs on the SERPs for your keyword phrases.