Polystyrene foam (styrofoam) is recyclable. It even has its own recycling code number, 6. However, most recycling centers won't take it. The biggest problem is that it is hard to clean effectively because contaminants can get inside the cells. This is especially bad if it was a meat tray, as blood and meat juices would rot and grow fungus or bacteria.

When thermoplastic is recycled, it's ground-down and superheated, etc, so the stinky-meat problem is only a problem for a short part of the cycle.

The real difficulty I see in recycling polystyrene (or other foams) is that it's not cost effective. First you have to use hot water and soap to wash them. Then you have to use gas (and a driver--people cost money) to move them to a recycling center, then you have to use electricity and an operator to grind them. Then you have to convince a manufacturer that your 'post consumer' waste will be okay in his 'new' product for him to buy it and mix it in.

But in the end, you've saved less than 5 ounces per meat-tray--maybe two cents worth--of polymer beads.

Meat trays and foam packaging added up to about a cubic foot per year when I tried saving them, and I think I'm pretty average in my usage of those materials, which would mean, I'm guessing, at least 20-50 million cubic feet in US landfills per year. It adds up. Anyone have a better idea for using this material?

Why can't meat trays, at least, be made of biodegradable materials? They used to always be paper.

The cubic volume of foam is deceiving--the minute they go into the back of the trash-truck, they're compressed with cylinders at 2000 psi. Pretty good chance that most of the air is smashed-out and the volume is about one-tenth what it was.

Most meat today is sold in Modified Atmosphere Packages (MAP), that is, the 'air' around the meat isn't air at all, it's a gas that will discourage breakdown of the meat and change of color. Often CO2, or for fruits, heavy on the O2. Paper trays aren't likely to be airtight and would be pretty difficult to melt the seal-celophane to the top.

Plastic is more sanitary than paper, too. But like Dwane said, you Can recycle styrofoam. If it's worth it to you, please do. If you watch Penn and Teller, you'll learn that Most of the recycling we do costs more than it would to buy new material. but that doesn't make it bad...

Some tidbits of info: 1. R-value(wiki, look it up) of polystyrene is one of the highest of any material, which makes it perfect for insulation.2. There are other sources of clean styrofaom trash like retail stores when they have left over packing material and if they would have an incentive to give it to you if you gave them money for it. As in: packing peanuts, all electronics packing material, styrofoam cups, construction site packing material waste, for many home depot products.3. Polystyrene may be considered an accelerant and therefor against building codes which is why you are correct that you may need to make it non flammable in some way.4. Also, find a good way of putting it into walls and ceilings?

An update on my own idea: concrete blocks with foam beads in the mix increase R-value. Meat and other contaminated material would be effectively sterilized by encapsulation in a concrete mixture, and such blocks are already on the market.

(I'm pretty sure hrench is mistaken on the trash truck compression issue: with closed-celled foam, there's very little compression. Concrete foundations and houses are often built on top of foam insulation because of its resistance to compression.)

We just had to replace a shower stall because of the foam under layer under the plastic floor compressing whenever you put all your weight on one foot. So the foam did compress and caused the plastic to crack and we had to replace the whole shower and get our money back for the badly designed structure.