Dropped a contact lens in a dirty sink. Now what?

It's a monthly lens, and has been used just once (pack opened on 13/3/2016).

While inserting in this morning at this friend's place, my upper eyelid slipped from my finger and my eye instantly blinked on its own, the eyelashes hit the lens on the tip of my other finger and damn, the sucker fell on her super dirty sink.
Can I disinfect it by soaking in Renu for a few hours and use it again? Or do I need to throw it away?
I'm on a tight budget and the lens is pretty costly:-/
But on the other hand the sink is super dirty, there's mossy patches and toothpaste stains on the sink and it's just yucky.

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