A Conversation On Compostables

Pick any product off a supermarket shelf and there is a good chance its either made from plastic or packaged with it. In an effort to tackle the growing waste problem, compostable products are now being made that break down readily, leaving no harmful substances.

In order to identify compostable products look for the seedling logo. To be certified compostable and carry the seedling logo, the product must readily break down in an industrial composting plant under controlled conditions such as temperature, moisture and time frame, leaving nothing behind but water, biomass and CO2. Home composting is the best option for those with a compost bin, just look for the above symbol which will appear alongside the seedling logo. Home composting requires a longer time period, usually up to three months to break down.

ECP ensures all their compostable bags are purchased with the seedling logo and meet AS4736 (commercial composting) and AS5810 (home composting) standards. In addition, ECP guarantees the shelf life of all their compostable bags is a minimum of 12 months. Some compostable bags currently in the NZ market have a very limited shelf life and this compromises the strength of the bags.

The conversation on compostable plastics has so far been focused on supermarket shopping bags. However compostable film is being considered to replace all film plastics; for example, the plastic that holds breakfast cereal or the packaging on kids’ toys. Some compostable products already available in New Zealand include checkout bags, bin liners, cling film, sandwich bags, doggy bags, and courier bags.

In agriculture, mulch films are used for growing strawberries, shrink wrap for wrapping pallets for transportation and there are more products coming out daily. Given all this work and continued research, it is a real shame that New Zealand is looking at banning compostable single-use bags, with the single-use plastic bag ban now under the microscope by the government. For more information, contact John Willoughby at john@ecpltd.co.nz.