Volunteers in Taylor Yard, a former railyard near downtown Los Angeles, are engaging in an innovative approach to tackle soil contamination. Despite the site’s picturesque appearance with rows of scrubby plants, the soil underneath holds hazardous heavy metals and petrochemicals, including lead, cadmium, diesel, and benzene. Led by Danielle Stevenson, a researcher from the University of California, Riverside, volunteers are investigating the potential of native California plants and fungi to remediate contaminated brownfields – land abandoned or underused due to industrial pollution.
Stevenson’s study, conducted as part of her PhD research, focuses on using native plants and fungi to clean up contaminated sites. Over the course of a year, her team planted California native shrubs and bushes along with symbiotic fungi at three contaminated sites, including Taylor Yard. They observed the plants’ ability to absorb contaminants into their roots, shoots, and leaves, likening them to “solar-powered vacuum cleaners.”
The success of this approach could have significant implications for the nearly half a million registered brownfields in the United States, particularly in California, where approximately 90,000 such sites exist. These brownfields are often located near low-income communities and communities of color, leading to disparate health impacts.
While the traditional method of remediation involves “dig-and-haul,” which removes contaminated soil to be replaced with clean soil, it can be environmentally damaging and culturally insensitive. In contrast, bioremediation, utilizing plants, fungi, and bacteria to clean up contamination, offers a potentially more environmentally friendly and cost-effective alternative.
Stevenson’s preliminary findings show significant reductions in heavy metals such as lead, arsenic, and copper across the study sites. However, further research is needed to fully understand and implement these methods. Despite the promising results, Stevenson’s study has yet to undergo peer review.
Local Indigenous and environmental justice groups have shown interest in bioremediation as an alternative to traditional cleanup methods. They view it as a means of advocating for more responsible land stewardship and empowering communities affected by contamination.
In Southern California, efforts are underway to apply bioremediation techniques in communities like Santa Ana, where low-income and marginalized groups are disproportionately affected by environmental concerns. Organizations like Orange County Environmental Justice are collaborating with researchers like Stevenson to test bioremediation methods and train community members in sustainable practices.
However, challenges remain, including gaining approval from regulatory agencies and overcoming skepticism from site owners and regulators. The tension between the priorities of Indigenous and marginalized communities and those of site owners underscores the need for more inclusive and collaborative approaches to environmental remediation.
As Stevenson’s research continues and community-led initiatives gain momentum, there is hope for a future where native plants and fungi play a key role in restoring contaminated lands and promoting environmental justice.