Generally speaking, if something is organic, it's probably best if it's not also horribly polluted. If it's organic compost, it shouldn't contain all the toxins filtered out of storm water, sewage, industrial and medical waste that gets flushed down the toilets of nine California counties. Except this time it did.

San Francisco residents with a green thumb were offered the chance to get some free organic compost, and they jumped on it (apparently it can cost up to $50 to lay out compost on a 10x10 garden. )

But the stuff they got was treated solids from the refining process meant to weed out fecal coliforms, pharmaceuticals, steroids, flame-retardants, bacteria, viruses and heavy metals from sewage and other waste water. As an added bonus, the coliforms have a tendency to regrow after the process and testing has shown that compost treated in this way tends to have things like pharmaceuticals, steroids and a bevy of other chemicals still right in place, ready to mess up your begonias.

The city defends itself, saying they have barely any industrial waste anyway. However, outside research shows a number of delicious industrial waste products in the mix including things like toluene and flame retardant chemicals that the CDC recommends humans have no contact with. Whatever else may be in there, it's probably a safe bet that you should give your San Francisco-grown veggies a good wash before eating them, just in case.