About the Authors
Center for Health and the Environment, University of California Davis, Davis, California, United States of America
The authors have declared that no competing interests exist.
Conceived and designed the experiments: BBD KEP. Performed the experiments: BBD YS RPD VF. Analyzed the data: BBD DJT. Contributed reagents/materials/analysis tools: BBD KEP. Wrote the paper: BBD RPD VF KEP.