Recycled irrigation water raises food safety questions
"Everyone smells the petrochemicals in the irrigation water," said Blake Sanden, UC Agriculture and Natural Resources Cooperative Extension advisor in Kern County. "When I talk to growers, and they smell the oil field crap in that water, they assume the soil is taking care of this."
The farmers trust that organisms in the soil remove toxins or impurities in the water. However, the trust may be misplaced.
Microoganisms in soils can consume and process some impurities, Sanden said, but it's not clear whether oil field waste is making its way into the roots or leaves of irrigated plants, and then into the food chain.
It's unlikely that petrochemicals will show up in an almond, for example, he said, "But can they make it into the flesh of an orange or grape? It's possible. A lot of this stuff has not been studied in a field setting or for commercial food uptake."
The reporter also spoke to Carl Winter, a UC ANR Cooperative Extension specialist based at UC Davis. He said some plants can absorb toxins without transferring them to the leaves or the flesh of their fruit.
Still, he said, "it's difficult to say anything for sure because we don't know what chemicals are in the water."
A visiting scholar at UC Berkeley who is a researcher analyzing hydraulic fracturing for the California legislature said the issue is "one of the things that keeps me up at night."
"You can't find what you don't look for," he said.