THE CLAIM: Plant-based packaged goods are sprouting up across Canada. Made from renewable resources such as vegetable oil and starch from corn or sugar cane, bioplastics, such as polylactic acid (PLA), are often touted as the earth friendly alternative to conventional petroleum or fossil-based plastics. Some products claim to be biodegradable or even 100 percent compostable. But are these materials really good for the planet?

THE INVESTIGATION: Bioplastics present a number of complex challenges. “There is a risk that a rather complicated issue is being oversimplified,” says Scott McDougall, president and CEO of TerraChoice, an Ottawa-based environmental marketing and consulting agency. In 2010 the company released a report called The Sins of Greenwashing: Home and Family Edition. McDougall says many bioplastics commit at least two of the seven sins.

First, the sin of the hidden trade-off: suggesting a product is green based on one set of attributes, while ignoring its wider—and possibly negative—effects. Take the ongoing “food vs. fuel” debate. Critics argue that bioplastics are contributing to the global food crisis by taking over large areas of land previously used to grow crops for food—raising the question of whether their potential damage outweighs their potential benefit.

Then, there’s the end-of-life issue. Many people assume a “biodegradable” product will break down no matter where it ends up. This is known as the sin of vagueness: a claim so poorly defined or so broad that its real meaning is likely to be misunderstood. In truth, most biodegradable plastics won’t decompose in landfills because the artificial environment lacks the light, water and air required for the decay process to begin. Even worse, bioplastics can contaminate the recycling stream if mixed with other recycled plastic.

Biodegradable plastic that carries the “Compostable Label” created by the New York City-based not-for-profit Biodegradable Products Institute are the exception. The logo identifies products that will perform satisfactorily in well-managed municipal and commercial facilities; home composts don’t generate the high temperatures needed for proper biodegradation.

THE VERDICT: Bioplastic packaging may seem like a magic solution, but it’s still an imperfect technology. While the demand for renewable materials, such as PLA, is a move in the right direction, these products can’t make a real difference until waste management systems are in place to support them. If you really want to reduce your carbon footprint, forget the plastic and try a reusable container instead.