CBEC, a Far North recycling business, says large recycling companies doing a sloppy job is the reason that China is cracking down on plastic waste.
Far North District Council is now sending a third of its plastics collection to landfill, because the recycling market for them has collapsed.
China is enforcing strict limits on the level of contaminants allowed in bulk imports of mixed plastics.
As a result, many major recycling companies have stopped their shipments, for fear of losing their import licences.
CBEC manager Simon Millichamp said big mechanised recycling firms worldwide are to blame, for sending off poorly sorted and contaminated plastics.
He said it is unfortunate community recyclers such as CBEC, which sorts and cleans plastics by hand, are caught up in the problem.