Compostable bag facts

Returning contents back to nature

If your community waste management systems offers commercial composting services for dog waste, using compostable pick-up bags formulated to meet ASTM D6400 standards would make sense. But EnviroWagg in the Greater Denver-Boulder area and Green Pet Compost in the Pacific Northwest are the only companies currently providing this service.

If you trash your pet waste, what is the point of using compostable pick-up bags? Unless the waste and bag are returned to nature through a methodical composting process, compostable bags have no function. In a sealed landfill, organics – including the organic materials in compostable bags – do not degrade as they would if exposed to air, light, heat, moisture and hungry aerobic microorganisms. They simply emit methane as they degrade over human lifetimes.

Bags identified as “biodegradable” or “oxobiodegradable” that are not designated ASTM 6400 “compostable” are made of plastic film with an added degradant that helps them break apart if exposed to the elements. As with compostable bags, the organic components of these bags do not fully decompose when hermetically sealed in a landfill. If the bags are allowed to break down in nature, the plastic pieces will stay intact in the soil, water and air.

California law prohibits the sale of a plastic bag or plastic food or beverage container that is labeled as “biodegradable,” “degradable,” “decomposable,” or as otherwise specified, eliminating dog waste pick-up bag marketing fraud.  The state also requires compostable bag suppliers to explain on their packaging that the bags should be streamed to a commercial composting facility for proper recycling.

All greened up with no place to go

Since nearly all dog waste in compostable or otherwise advertised “biodegradable bags” is tossed in the trash, why not just recycle that old newspaper or shopping bag for pick up? Really. Unless compostable bags are used as part of a recycling process, they actually have drawbacks. Here are three of them.

1) Do it yourself composting: Promotions often lead buyers to believe that compostable or other “biodegradable” bags can be used with various doggie septic systems or for backyard “composting.” But the bags don’t break down if they’re not composted using light, heat and air and will disrupt a septic system. Because they don’t break down, the compostable bags fail to expose the waste inside elements

2) Price: Certified compostable bags can cost twice as much as bags made primarily of plastic. Compostable bag manufacturers foresee lower prices only when demand accelerates due to plastic bag bans and organics composting.

3) Magical thinking: Bags labeled “compostable” or otherwise “degradable” may even impede efforts to keep parks and waterways free of dog waste pollution. Some pet owners leave “biodegradable” bags on the ground or cover them with dirt with hopes that they will quickly degrade. One dog owner said (true story), “These bags are great! I leave them in the field and when I come back they’re gone.” Nature does not embrace the bags. Someone picks them up or they simply blow away.

So what’s the answer?

Considering that the dog waste you responsibly pick up and trash is headed for a landfill, a smart environmental choice would be to re-use plastic bags. Doing this instead of buying pick-up bags eliminates the need to produce and transport new bags.

Related: FTC’s recent press release regarding degradable dog waste bags and false advertising.