Produce Exposed to Smoke
Air quality in Sonoma County has been significantly impacted by the ongoing fires in the region. Local farms have played a very large and important role in food relief efforts immediately following the start of the fires and the mass evacuations. Many farmers and others in the community are concerned about how the air pollution might be impacting produce. While the University of California does not have data on the levels of these chemicals in produce that have been in contact with smoke and ash, we understand the need to share information with our community at this time.
If the air pollution has particulate matter from treated timber, tires, non-food grade oils, or anything plastic or chlorinated that burned it may include a mixture of Polycyclic Aromatic Hydrocarbons (PAHs), dioxins, and metals. Exposure to fire retardant may have also occurred.
An unpublished literature review on the health impacts of PAHs from traffic-related air pollution on lettuce grown in urban agriculture found that:
- Some PAHs can be absorbed into plant tissue, and so cannot be simply washed off.
- The health risk from eating these PAHs is a small proportion of the health impact from breathing them, and it is far below the EPA’s level of concern for lifetime cancer risk.
- It is possible that the health benefit of eating the vitamins and nutrients in green leafy vegetables might outweigh that negligible negative impact.
- There is not enough research available on the cumulative impacts of air pollution on produce to make any solid conclusions about the health impacts.
Produce Safety after Urban Wildfire study conducted following Oct 2017 fires in Sonoma County.
Fires & Food Safety flyer by USDA FSIS, 2/2013.
Food Safety after Fire by USDA FSIS, 8/2013.
Some technical guidance tip sheets and power points that may be helpful can be found here:
- Soil Sampling, Risk Mapping & Exposure Prevention - Rob Bennaton
- Contaminants in Soils, Data Collection-Interpreting Test results and Minimizing Exposure by Cornell University
- Testing Laboratories in Northern California
- UCCE Soils in Urban Agriculture
- Best Practices for Produce Safety After A Fire
- Produce Safety After a Fire Tool Kit
* * * During a Disaster * * *
If you need assistance with your crops during a disaster, please contact:
Sonoma County Department of Agriculture
Assessing Ag Losses
- Crops: Mimi Enright will coordinate firstname.lastname@example.org
- Livestock, Range, Pasture: Stephanie Larson email@example.com
- Trees, Forest: Steven Swain firstname.lastname@example.org
Crop Loss Reporting
Damage Assessment links coming soon! Updated 11/5/2019
- Crop and Livestock (PDF: 1.7 MB)
- Vine and Tree (PDF: 719 KB)
- Response to wildfire impact on CA wine industry and smoke taint UCD Vit & Enology Dept, 10/2017
- Smoke and Grape – the Smoke Taint Repercussions, Viticulture Blog, Fruition Sciences, 10/2017