I figure most pesticides, fertilizers and herbicides are going to be far gone in eight months - two years time. If these things were so long lasting, there wouldn't be a need to treat a yard more than once every other year.
Maybe you all's city is different, but around these parts, they don't add sewage treatment or anying to the compost - it is made from picking up grass clippings, leaves and branches from trees, shrubs, etc. It's usaully on a twoyear cycle, meaning the compost your buy now is from 2006's crop.
I would use it in a heartbeat. YMMV.
Mike