Moth ball and black widow spiders? True?

Is it true if you put a bowl of Moth balls in every room of your house whether there are any black widow spiders they will leave and go external? How long do you leave them in the room? And what about other pets does it bother them?
I am not certain if this is true, but please do not leave mothballs where pets or children can go and get to them. they are toxic and will kill if ingested!
I don't believe that moth balls work on spiders. I've never seen any evidence of that. I've used moth ball for other things and still get spiders. The moth balls will, however, irritate dog and cat noses so I wouldn't want them around much.
Answers:    I dont imagine they would work but all i know is that mothballs are nothing but trouble if you ask me. They can butcher as they are toxic and can irritate any pets noses and if digested can kill.

Hope this help and good luck. :)
it might bother the pets because it is proven that it keeps absent snakes but i don't know about spiders.
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