Highlights:

• Powerful herbicides, Clopyralid and Picloram, have been found in compost produced in Vermont
• Sales of bagged and bulk compost have been stopped but the State Health Department does not expect the contaminated compost to cause harm to consumer.  They are advising consumers to make their own choice before consuming produce grown in the compost
• Exact source of the contamination is unknown.  Speculation is that this is the result of illegal use of banned weed killers
   

From the article:

The herbicide contamination of Green Mountain Compost is more widespread than originally thought and appears to be largely the result of illegal use of weedkiller.

Tests on Green Mountain Compost show that trace amounts of what’s known as persistent herbicides have turned up in compost products sold in bags, not just bulk compost, as officials previously thought. Sales of bagged compost and related products were stopped immediately when the results came back Thursday, said Tom Moreau, manager for the district, which runs the compost operation.

Test results show the herbicides Clopyralid and Picloram — which the state prohibits from being spread on lawns — were found in all eight samples the Chittenden Solid Waste District sent this week to a laboratory in Idaho, Moreau said. More test results are pending.