Hazard assessment of chemical additives used in oil fields that reuse produced water for agricultural irrigation


This report — written by researchers at PSE Healthy Energy, UC Berkeley, Lawrence Berkeley National Laboratory, and the University of the Pacific — shares preliminary findings on the chemical additives used in oil fields that provide produced water that is reused for agricultural irrigation of food crops, livestock watering and recharging aquifers. Oil field produced water has been used to irrigate food crops in the Cawelo Water District since the mid-1990s. Recently, this practice has been expanded to North Kern Water Storage District in the San Joaquin Valley of California. The reuse of such oilfield produced water is being examined as a potential source of water for for wider use in agriculture, livestock watering, groundwater recharge and possibly drinking water in California, Western States, and increasingly throughout the world. One important knowledge gap with respect to assessing human health and environmental hazards of reusing this water is understanding the types of chemical additives, not just naturally occurring chemicals used during oil and gas development. It should be noted that these oil fields have, for the most part not been hydraulically fractured, however chemical use from routine oil and gas development activities appears to be widespread, necessitating further investigation for public health concerns.

This report contains preliminary findings of the analysis of the list of chemical additives used in the oilfields from an information disclosure order from the Central Valley Regional Water Quality Control Board in California. Here, we assess the disclosed compounds for acute mammalian and ecological toxicity, biodegradability, bioaccumulationn potential, carcinogenicity, and whether chemicals are included on State or Federal chemical advisory lists. The purpose of this analysis is to identify chemicals of potential concern as a first step prior to more complete human health and environmental hazard and risk analyses that should be undertaken.

Please note: the findings of this report belong to the co-authors and do not necessarily represent the opinions of the Food Safety Expert Panel convened by the Central Valley Regional Water Quality Control Board in California, or any other party.

Download the PDF here.