[winterismute]

My wife was wondering whether this can be considered 100% healthy: don't you need plastic to reach a very high temperature to model it that way? Doesn't it start releasing whatever thing that might be carcinogenic or such?

[maxerickson]

Thermoplastics will melt before they start to chemically decompose. Whatever residue is in the plastic might be liberated by the heat (those residues will also migrate out at room temperature, so we tend to be somewhat careful about what residue ends up in products).

Thermoset plastics will not melt and will release all sorts of magnificent things when heated.

https://en.wikipedia.org/wiki/Thermoplastic

https://en.wikipedia.org/wiki/Thermosetting_polymer

[justifier]

http://preciousplastic.com/videos/plastics/

they have a section discussing different kinds of plastics, and simplifies the information to the notion that if the plastic lacks a recycling symbol then it is in the category of 'unrecyclable'

[tripzilch]

some of the harder plastics used in 3D printing also have a very particular smell. it sort of hints to me "perhaps not be in the same room when it's operating" (getting a whiff versus standing there breathing it for an hour), and ventilate after.

unless you're worried about getting it out in the air at all, also outside. in which case I'd start with avoiding campfires, (certain types of) barbecues and petitioning your neighbours to stop using their fireplaces, good luck :p

and like others said, it's not a very high temperature.

about that "thing that mgiht be carcinogenic or such", do you mean phtalates? i might have spelled that wrong, the plastic-softener compound. it's not present in equal amounts in all types of plastic, definitely not those intended for food-containers. if it's present in higher amounts you can easily smell it, it's that particular smell that is on that soft, rubbery, "soft-grip" plastic, especially when it's new.

btw not even living itself is ever "100% healthy" :) it's always a trade-off, and in this case, it seems pretty good, trade-off is for the planet and the children :-)

[meapix]

I was going to ask the same thing, this is worse than throwing in dump where it will decompose and hundreds of years.