That depends entirely on the recycling facility. Many things contaminate recycling streams. Food particles, and especially oils, remaining on food packaging contaminate recycling streams. Lids left on bottles and jars contaminate certain recycling streams. Labels left on containers can contaminate recycling streams. Basically, anything that requires a material to be further manipulated, washed or sorted is considered to contaminate the recycling stream. PLA often takes the rap for all of this, but it’s no more contaminating than any of these other factors. Another aspect to contamination is if a recycling facility is not receiving enough of a particular type of material to economically sort and re-sell it for profit. Many recyclers are optimized to sort PET #1 bottles and HDPE #2 milk jugs for this reason (which is why we think our new Bio-PET is a pretty neat idea to make a positive environmental impact on two fronts!). When a material arrives that does not meet this profile, recyclers complain that it creates delays and reduces their profitability. For many recyclers, PLA is still in the “too small to bother” category, but that does not mean it’s contaminating at a technical level.