Trash is a big problem for the environment. Unsurprisingly, the U.S. is the worst (or best, depending on how you look at it) in the world for producing garbage, throwing away two billion tons annually. And while recycled materials have come a long way in helping us to reduce our garbage, there is something else that can be done and this includes an interesting insight into product design.

Turns out that how consumers decide if something is trash or recyclable isn't based on whether the product is, in fact, recyclable. It has more to do with the appearance and size of the product. If it looks like trash, then it will be less likely to be recycled.

Products change during their use. Paper is torn, cans are crumpled. And how form or size changes impacts the likelihood of a product being recycled or just tossed in the garbage. This is the finding from a recent study in the Journal of Consumer Research [PDF].

Scientists asked subjects to test out a pair of scissors. They asked some subjects to cut paper with the scissors, and others were told to evaluate the scissors without cutting any paper. Then, after the supposed "experiment" was over, the scientists asked everyone to "dispose of all their paper on their way out."

Meanwhile, here was the real experiment: Next to the exit sat two bins, one labeled for recyclables and the other labeled for trash. And they found that those who had cut up their paper were much less likely to recycle it (only 44% of them recycled the cut paper) than those who carried whole sheets of undamaged paper (86% of this group recycled whole sheets.) All subjects had the same amount of paper and in a survey all recognized that recycling is very important.

Here's a main insight the scientists gleaned from the follow-up survey: Subjects tended to see the cut up paper as less useful than the whole sheets, and this probably had an impact on their ultimate decision to recycle.

In a second experiment scientists presented subjects with two different-sized aluminum soft drink cans, either a 12 fl oz can or a 7.5 fl oz can. And they found that participants were more likely to recycle the regular sized, 12 fl oz can than the smaller 7.5 fl oz can. Giving the participants a slightly crumpled can decreased overall their likelihood for recycling either sized can. But, there was still a bias to recycle the larger can (over the smaller one) even though it was dented. Somehow the larger, damaged, can was seen as still more useful than the smaller one. So size is an important factor in the consumers' choice to recycle.

For product designers with an environmental bent, maybe one solution is to create forms that are able to maintain their shape, or easily bounce back when dented. But above all, maintaining usefulness appears to be the key point, as the authors of the study write: "...changes in size and form have a significant impact on the perceived usefulness of a product and ... usefulness is a category-defining attribute for recyclables and trash."