Does inorganic arsenic, like the kind that was once used on treated wood as a pesticide, bioaccumulate?

Question

I ask because this quandry is pertinent to my circumstances.

I have two cats who spend the majority of their day sleeping, playing, and rolling around on a deck that was built using arsenic treated wood. The wood on the deck is /very/ old and withered (does this mean the arsenic has come off of it?). At the end of the day, the cats come in my room, rub all over me, sleep on my bed, etc. Whatever they had contact with.... gets onto me. So I'm curious. Could there be any health consequences because of this? Does the arsenic in these miniscule quantities quickly pass through the body and get urinated, sweated, and excreted right back out, or does it start to accumulate in organs.. and could damage brain cells, or potentially cause cancer at a later age?

In addition, in these quantities, would the arsenic have any bearing on cognitive development or performance? I'm intellectually ambitious, and so the threat of something hampering or ruining my academic chances is unacceptable.

-- Oh, and, as an aside. If I were to graze the wood with an open wound, or touch it and then eat without thoroughly ridding my hands of the arsenic, what would happen in these instances?

Answer 1

Arsenic is extremely toxic and hard to get rid of. Yes it can bioaccumulate and kill lots of cells. You might want to stop allowing your cats on that deck!! If you get enough arsenic you can start to get sick and yes it is known to cause cancer.

Why would wood decks be treated with a lethal poison? Either your deck is very very old when nobody understood anything about arsenic or the person who manufacutures this is VERY breaking the law.

Answer 2

Yes it bioaccumulates, yes arsenic is leaching out of the wood onto the surface (if it was treated with an arsenic-based preservative (it probably was, but there was copper-only-treated wood as well)), yes your pets are being contaminated, yes they are exposing you to arsenic, and yes it is an issue.  On the bright side, cats are to a large extent self-cleaning and they likely groom most of the arsenic off of themselves before they come back inside.  

There is, however, something you can do to alleviate the problem:

http://www.mchd.com/pdf/ccawood.pdf

Sealing the wood as described above prevents arsenic from leaching.  

Also, there is epidemiological evidence that arsenic exposure affects cognitive development in young children.  Less is know about its affect on older children and young adults.

http://www.ehponline.org/docs/2007/9270/...

It is a good idea to minimize arsenic exposure.  Your parents probably will object to your ripping out the deck, but sealing it is a very good idea.  Wear a good organic vapor mask for sealing, take the time to brush the sealant on rather than spray it, because you can get a nasty headache from linseed-oil based sealants on a hot day.