Compost differences

That's always been my worry about green waste, TMTT.
Joe Bloggs may not have a compost heap, or doesn't want to put treated grass cuttings in there so puts them in the garden waste bin. Household waste bins, here anyway, are too small for filling with grass cuttings - in fact I think we've been told they're not to be used for garden waste. How else would Joe BLoggs get rid of them??

They also say on the label to leave the first clippings on the lawn, which is actually very good for recycling nutrients back in to the soil but if you walk on the grass you pick clippings up on your feet and spread them everywhere. They then say to compost subsequent clippings 'well' for at least 9 months and then use as a mulch. Most people don't compost at all, let alone well, so...

Reading the quality requirements for green waste compost, if they conform to BSI Pas 100 standards they have to test for heavy metals and do tomato/field bean growing tests where 80% of the seed has to germinate/subsequent plants have no abnormalities/grow to 80% of the weight of a peat based control. So you assume that any weed killer contamination would get picked up somewhere along the way, but obviously something is going wrong in the quality control process.