One other consideration when adding any plastics into ecosystems is ingestion by animals and bioaccumulation. Marine and land animals are known to mistake small pieces of plastic for food and eat them, which occupy space in the animal's digestive system. This is particularly true of marine mammals and birds, and a lot of plastic washes down storm drains and into the sea. The animal can feel full from eating this material but gets no nutrient value. Animals have also bee known to choke on plastics.
Very small pieces of plastic can be eaten by small organisms, which in turn are consumed by larger animals, and so on. Since an animal higher on the food chain may eat many smaller animals, more plastics can accumulate the higher in the chain you look. Anything not easily passed through the digestive system can build up over time. The ultimate consequences of this are not fully understood.
My own feeling on this is that it is not wise to introduce materials or organisms into an ecosystem that it did not evolve to deal with.
That said, Dart Container Corporation does have a recycling program for post-consumer food grade polystyrene. Larger generators can lease a densifier if they purchase Dart products and Dart will collect the densified material. You can check these websites for more info and "do the math" to see if this program will work for your situation:
Terry S. Brennan
Integrated Waste Management Specialist
California Integrated Waste Management Board
phone (916) 341-6578
fax (916) 319-7474
From: SPENDELOW Peter H [mailto:SPENDELOW.Peter.H@deq.state.or.us]
Sent: Monday, July 01, 2002 9:35 PM
Subject: Re: [GreenYes] Polystyrene Food Containers
The answers to your question on using chopped polystyrene to try to
aerate soil certainly went far afield. People started talking about
talking about alternatives to foam polystyrene packaging - a valid
subject but not in response to your question. I don't think those
starch-based packaging materials would do anything for soil aeration....
I can give you a partial answer to your question. Foam polystyrene is
pretty stable/inert in soil. I've seen foam blocks that have been
buried in potting soil for a couple of years, and they look just like
they originally did, except dirtier. You can also find foam polystyrene
cups that have been littered for years later. I doubt if the
polystyrene would show any significant biodegradation for many years.
There might be some compression over time.
I wouldn't recommend using polystyrene foam bits for two reasons though.
First, it is a real mess to chip up into little bits, and there could be
health implications if the foam is heated in the chipping process
possibly releasing styrene or other nasties. Second, who wants to have
little bits of polystyrene foam blowing all over your yard? It isn't
very aesthetic. I would stick to something like pea gravel or pumice
for aeration, although pumice will break down over time.
It might be interesting using foam plastic bits in a potting soil mix,
as people don't like carrying heavy plants when they are shopping. We
buy lots of perlite to lighten our potting mix, but I've heard perlite
is pretty energy-intensive to produce. This might be a possible use of
a pretty unpopular waste product. However, aesthetics could still be a
We had a question from a resident regarding the polystyrene containers
that come wrapped with meat products (poultry, etc.). The resident was
wondering if that material could be finely chopped and used for aeration
purposes in a home garden.
Does anyone have any information on the stability of that material over
time or its suitability for this purpose?
Jeffrey W. Aluotto
Hamilton County Solid Waste Management District
ph: 513-946-7719 fax: 513-946-7779
To post to the greenyes list,
email to: firstname.lastname@example.org
subscription, faq and netiquette info for
this list are available here:
Please be sure to read the faq and netiquette
pages before posting.