Having just returned from the annual US Composting Council’s Conference we are more energized and inspired than ever. It was amazing to spend four days with other people tackling the same issues and dilemmas we discuss daily. One of the most contentious topics at the conference was “compostable products.” There was an entire track dedicated to the production, use, collection, testing, and compostability of certain bio-based products currently on the market. In attendance were bio-plastic manufacturers, standards setters, chemical engineering professors and composters- each with differing views. Below is an overview of some of the topics and issues surrounding compostable products.
1. Are they Compostable?– there are a raft of new products out there claiming to be compostable, or biodegradable, or bio-based, or made from plants, or green or brown, or whatever. The reality is there are bio-based products that won’t compost, petro-based products that will, and vice versa. There are two main standards for compostability on the market: BPI certified (Biodegradable Products Institute) and ASTM D6400. These two standards address how completely and how quickly a product will break down in a traditional commercial compost facility- except that they are lab standards and do not test break down in a compost facility- they test in a lab. To answer that, Cedar Grove, one of the largest and most progressive composting facilities in the US, does their own testing to see how well a certain product breaks down in their piles. They publish lists on their site, which are a great resource. Except, their facility is progressive and advanced, and therefore not like others (or ours for that matter). They used forced air and in-vessel technology, and we use open windrows (much lower tech), so there still remains a question of applicability. In the end, our takeaway is that each facility needs to test products for compatibility in their own piles. We have starting doing so, but each product tested takes time and effort, so we are plugging our way through as time permits.
2. Are they Organic?– Currently the National Organics Standards Board considers bio-plastics as a non-organic feedstock. Thus, by accepting compostable products our compost would not be classified as organic (we typically follow the OMRI specifications for Organic classification). In response, MSU Professor Narayan gave a very interesting lecture demonstrating that all products meeting ASTM 6400 are actually over 99% consumed as food by compost mircobes, thus leaving nothing at the end of the process. His claim is that a product cannot be non-organic if it has been completely consumed organically by mircrobes. Huh. The takeaway here, is there is a loooong way to go before NOSB approves bio-plastics, but there are a few minor loopholes. One is incidental material. There is a clause in NOSB that if compost piles incidentally contain bio-plastics they may be permissible. The second was a recommendation to allow compostable bags, since they are essential to collection and therefore landfill diversion of material (versus a cup or a plate). The debate continues, but in the meantime some composters are processing two streams one organic (no bio-plastics) and one non-organic (containing bio-plastics).
3. How are they Labeled?– This is the real hum-dinger. As mentioned above new products claim all sorts of environmental benefits. The problem is even the most highly educated and discerning bio-plastics experts can’t tell what is what. Is it bio-degradable, or compostable, or made from plants, but basically plastic? Who knows? The result is these materials are mistakenly considered “compostable” which then enters the compost stream, but acts as trash. In an enlightening presentation, Cedar Grove VP Jerry Bartlett, demonstrated through the value cycle how mislabled compostables costs him a boat load of carbon and $100/ton to process over sending them directly to the landfill (which is where they end up). The takeaway here is that there needs to be a set of standards for compostable products and one that meet that standard need to be labeled clearly.
The Dirt Hugger Challenge– I didn’t get a chance to stand up and say this, but if I had a one, five or even ten year challenge for the bio-plastics industry it would be to develop a standard for compostability in the two most prevalent technologies (open windrow and aerated static piles). Products that meet these standards would also meet NOSB’s organic standards. Clearing these two hurdles, the product would be labeled in enormous letters “compostable.” (I’d suggest orange colored, since orange hasn’t been played out by the greenwashing industry, yet). This solution allows compost facilities to directly identify products that will compost, won’t be landfilled and will maintain their organic certification.