Toby and I are looking at buying tubing and fittings made from non-PVC plastics. Find information about the toxic and possibly carcinogenic properties of different plastics in the following (mostly unfiltered) links:
Greenpeace PVC Alternatives: http://archive.greenpeace.org/toxics/pvcdatabase/bad.html
Plastics Scorecard: http://cleanproduction.org/Scorecard.Grades.php
Smart Plastics Guide: http://www.healthobservatory.org/library.cfm?refID=77083
Anti-PVC Website: http://www.besafenet.com/pvc/index.htm
Cute Anti-PVC Video: http://pvcfree.org/
Bioplastics: http://en.wikipedia.org/wiki/Bioplastic
Vinyl Usage in the House: http://www.pvcinformation.org/assets/pdf/ThisVinylHouse.pdf
Plastics used for tubing: http://en.wikipedia.org/wiki/Pipe_fitting#Plastic_pipe
Greenpeace offer a number of useful guides to 'eco-friendly' materials, for instance this Green Guide to Electronics: http://www.greenpeace.org/raw/content/usa/press-center/reports4/green-guide-to-electronics-fo.pdf
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