Many years ago, I took a course in industrial chemistry from Dr. Martin Hocking at the University of Victoria.
In the course, we discussed many of the chemical industries from the perspective of the products they produce, the chemicals used in production, and the waste streams generated by the various industries.
Many industries are much better now than they were then. Most are highly efficient with effective internal recycling of materials and minimization of waste. Our local pulp mills, for example, have done a tremendous amount work cutting down on pollutants and finding ways to minimize their discharges.
These efforts include decreasing the amount of energy used in making products.
The energy consumption per sheet of paper has been steadily decreasing over the past century as has energy ratios for many over products.
But the overall question of inputs and effluents is a tricky one to deal with.
There are so many factors at play that a whole new area of study has emerged in the form of life cycle analysis. The idea is to look at all of the inputs and outputs for any product from the cradle to the grave. Some would argue it should be from the cradle to the cradle as everything should be recycle-able.
Dr. Hocking was a pioneer in life cycle analysis with his work on the great "paper vs plastic" debate.
His research on life cycle analysis led to a conclusion that surprised both environmentalists and industrialists alike -- if you take into account all of the energy consumption, you use less energy (or petroleum) to make a Styrofoam cup than you do to make a paper cup.
Hocking's initial analysis lead to flat out denials from the pulp and paper sector and cheers from the petrochemical industry. I remember a spokesperson from McDonald's commenting they knew all along that their Styrofoam containers were more environmentally friendly but they had bowed to public pressure in bringing in their paper wrappings!
Of course, they didn't mention the real reason was one of storage and transport.
In 1994, based on total energy analysis, Hocking was able to show that Styrofoam beat out the ceramic coffee mug unless you used the coffee mug for a very long time and have a very efficient dishwasher.
A ceramic coffee cup requires 1,006 uses before the energy payback makes sense. Put another way, it needs to be used daily for three years and washed in a very efficient dishwasher before it will use less petroleum than a polystyrene cup. (Dishwashers, by the way, beat the hand washing of dishes in terms of energy usage.)
Critics, and there were many, pointed out ceramic cups leave much less waste behind and are not as disruptive to the environment. A fair argument provided the material used to make the ceramic cup did not need to mined.
Many authors have pointed out paper cups are biodegradable whereas Styrofoam and ceramic cups are not.
No question about this -- if you take a long enough time span. However, despite being made from "all natural" sources, the cellulose from which paper is made does not degrade very quickly. A few hundred years, maybe, but not at an appreciable rate within our lifespan.
The coffee cup debate appears to have been won by the paper cup companies.
Starbuck's and Tim Hortons serve all of their millions of coffees in paper based cups (coated to resist the infusion of water into the cup material, thereby ensuring that they will be around for even longer).
Indeed, it is virtually impossible to find any fast food served in a Styrofoam container.
However, another battle has been going on for almost as long. It is the question of paper versus plastic bags. This battle appears to have been won, hands down, by plastic. Trying to find a paper bag when checking out at a store is a bit like finding the proverbial needle in a haystack!
The argument still rages, though, and there is a new contender on the block -- the cloth grocery bag.
It is gaining traction as many cities and states are considering outright bans of plastic bags. Unfortunately, it only seems logical as it is misguided.
Recycleable bags made of cotton have a limited life span. If washed in machines about as energy efficient as dishwashers and used over 150 times, then a cotton bag might win. But so far, their usage patterns don't justify the switch.
I am not a big fan of plastic bags littering our environment. They have too many unintended consequences. But in our efforts to create a greener, more environmentally friendly world, we need to keep in mind all aspects of every product. Life cycle analysis should be mandatory.
Then consumers would really be able to judge for themselves.
