PLA - not for the yellow bin
PLA or Poly Lactic Acid is a relatively new polymer derived from
natural materials such as corn starch, tapioca or sugar cane.
It's used as an alternative to conventional oil based polymers in a
wide variety of applications including food packaging.
Unfortunately within Christchurch, PLA cannot be considered
recyclable or compostable through the kerbside collection
One of the key drivers for the use of PLA is its bio-degradable
properties under the right conditions. When placed into a
composting facility or a domestic compost heap, the PLA will
degrade over time. When left exposed to natural elements, the
PLA will also degrade but over a longer period.
Despite the advantages of PLA, there are also some significant
One of the most significant disadvantages is identifying the
material within the waste stream. PLA has been engineered to
look the same as its conventional alternatives meaning even to the
trained eye, it's difficult to separate. Therefore, ensuring
PLA does not contaminate other plastic grades can be very
hard. Contamination within another sorted plastic grade can
mean a customer has the right to ask for a reduction in cost or
reject the shipment altogether.
Another factor is the volume of PLA currently present in the
waste stream. In Christchurch we are collecting between 15
and 20 tonnes of clear PET bottles per week - enough to fill a 40ft
container. We estimate at present we are receiving 500 kgs
per month of PLA meaning it could take 3 years to fill the same 40
ft container. However, to begin collecting PLA, we would
require a re-engineering of our Material Recovery Facility where we
can divert PLA into a dedicated collection point.
Compounding this, the recycled PLA market has a low commodity
price and presently costs more to ship a container of PLA overseas
to a recycler that the actual material is worth. Therefore it
is not financially viable for EcoCentral to begin sorting PLA for
For information about the commercial composting facility, please
visit the CCC website at
or the Living Earth website at http://livingearth.co.nz/faq/christchurch/
With the above in mind, the only places where PLA can be
disposed of in Christchurch is within domestic compost heaps or the
Red Bin kerbside collection service.
We ask than any manufacturer who is seeking to use PLA or
another new packaging material consult with their local waste
stream contractors to understand the impact. By understanding
what happens once the consumer places the empty packaging into the
right bin can the complete chain of custardy be fully