The plastic is methyl methacrylate polymer and is tolerated by body tissues. It even is slightly bactericidal to a small degree. It is routinely used for prosthetic eyes to replace surgically removed eyes. Acrylic polymer is UV transparent, to the extent that people who have acrylic eye lens prostheses for cataract problems can see to about 340nm. This was reported by Horace Dall who used a spectroscope in his work and found that he could see well into the UV after his cataract operation!
---------------------------------------------------------------------- A. David Beach MNZIP MRNZS.................Industrial Research Limited Scientist....(d.beach@irl.cri.nz)..........24 Balfour Road Machine Vision Team.(http://161.29.40.7/)..Parnell Production, Automation and Control.........PO Box 2225, Auckland Ph +64-9-303-4116....Fax +64-9-302-8106....New Zealand ----------------------------------------------------------------------