Regarding the Nov. 19 "The Plastics Blog" item by Don Loepp, "Plastics Hall of Famer stands up for polystyrene,"] Professor Richard S. Stein is absolutely right to mention that polystyrene disposables or cups are made from polystyrene and not styrene. Polystyrene is cleared by the Food and Drug Administration for direct food contact and has been found to be at least as good or better as paper board in several life-cycle assessment studies. The PS foam products in question are lighter-weight than anything else.
Also recently, there have been done some migration studies where no styrene could be found to migrate from PS products. The detection limit level was 0.1 ppb, equivalent to less than 1 person in the world population.
Recycling of those products would be, of course, the best alternative for reusing the material, as demonstrated in Amherst, Mass., the city Professor Stein was writing about. This could have been presented as an example of what one can do and how one can do it, even generating new employment and opportunities for small businesses instead of banning plastic. Despite recycling efforts, some part of the PS will still end up in landfills and does not degrade the same as other products such as paper and polylactic acid. PS can be made, however, biodegradable by using some additives, such as those from ECM Biofilms Inc. in Painesville, Ohio. Relative to the total amount of material, those additives are not very expensive and they do not prevent recycling and re-use. They, however, do not degrade in the requested 90 days
by some ASTM requirements tailored to the needs of industrial composting plants. It takes much longer but so what? At least the material completely degrades wherever there is microbial activity, such as in landfill.
The efforts of pressure groups and politicians jumping on the bandwagon to ban such PS products cannot be supported by facts. The conclusion drawn from this situation should be that every city banning PS should place a large billboard next to the city's name sign: "Beware of the 'Green Holy Inquisition.' "
There are certainly other issues relating to the use of PS in packaging and this does not only apply to PS packaging. My headline here would be "Shame and scandal in the industry."
Disposable PS foam cups, as well as some yogurt cups and similar products, are decorated with in-mold-applied paper labels using heat-activated adhesive. Once those labels are combined to the PS drinking cup or yogurt pot, you cannot separate the paper from the PS anymore. Everybody in the industry would know what paper fibers in your plastic melt would do negatively.
Despite this packaging being unrecyclable, it's still allowed to use the No. 6 code for PS, which many consumers believe means it would be recyclable. This is absolutely wrong. Therefore, one should use a PS label on a PS cup. The label could be applied without adhesive or at least with something that doesn't hinder re-use. As other people have shown, a fully PS-containing packaging material can easily be recycled and made into useful products.
People using paper labels will probably tell you that a PS label would be more expensive, which may be right. But the differences are not really significant and only fractions of a penny. If such unrecyclable cups or packaging would be marked properly with the right number for unrecyclable materials, the waste levies for such products would probably outnumber the small add-on cost for a label that makes the cup material reusable.
I guess to go after this issue using facts would be a much better playing field for the "Green Holy Inquisition" than banning something without having any proper facts.
Peter Heymann
General Manager
Gerro Plast GmbH Labels