actions have consequences

Recycling becomes impossible
When the occurrence of contaminants in a load of recycling becomes too great the items will be sent to the landfill even though some of them are viable for recycling. This happens because recycling is a business. If extra costs add up simply to separate out the contamination, it is likely that a use for that money will be found elsewhere.

Recycling machinery maintenance
Plastic bags, as mentioned, can wrap around the shafts and axles of a sorting machine and endanger the sorters who have to remove them. When the machine breaks and the sorters have to dig them out, that is time and energy wasted.

Unsafe work environments for those sorting your stuff
When improper, non-recyclable items contaminate the sorting bins, recycling workers can be exposed to hazardous waste, vector-borne diseases (living organisms that can transmit infectious diseases between humans or from animals to humans), and other physically damaging items.

The paper, cardboard, plastic, and metal commodities in your recycling have value aside from benefitting the planet. If a contaminant is present, the quality of the recyclable is reduced or eliminated. This gives recycling less market value, and the local recycling program may suffer as a result. Ultimately, this could result in an increased cost of service or in some cases elimination of the program altogether.

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the battle against contamination is everyone's battle

stricter rules on the cleanliness of recyclables imposed by buyers of recyclable materials means contamination is a bigger concern for recycling than ever before