If you wonder what you should do about low quality back links, or links from low quality websites or bad neighborhoods, don’t stress too much. There’s not a lot you can do other than write to the webmaster and request that your link be removed. But that’s rarely necessary.
The search engines know you cannot control who links to you. They don’t generally discredit bad links. They may not count them, but they won’t penalize you for being linked to. That frees up your mind to worry about other details.
Back links are something that everyone covets. And most webmasters want the best back links they can get. But don’t get too infatuated with back links. You’d be better off planning and creating fresh new content. That’s what the search engines really love.
The only worry you should have about back links is whether you are being aggressive enough in pursuing them for your site.