Tribal-led pilot detects microplastics in rain and snow; researchers stress tribal data ownership

Fred Bionis, CEO of the Native American Fiber Program and a representative to the California Water Quality Monitoring Council, presented a tribal-led pilot study showing the presence of microplastics in rain and snow and described agreements designed to keep control of resulting data with participating tribes.

Bionis framed the work as an extension of tribal water stewardship and traditional basketry medicine, saying tribes developed low-contamination collection methods (metal or glass vessels, lab-provided jars) and sent samples to Stanford’s Labau Labs for analysis. He said year-one work was a pilot focused on presence/absence and that concentration values will be published only after replication and quality-control checks.

The pilot’s initial laboratory findings identified four broad types of particles in environmental samples: thin films consistent with baggies or bottle fragments, fibers likely from textiles, assorted fragments, and dark-colored clusters. "We saw thin film, fibers, fragments and clusters — they are present," Bionis said, while cautioning that "we want to replicate and reassure before we share concentration values." He emphasized the need for more instrumentation and standardized methods before drawing conclusions about exposure levels.

A central aim of the project is data sovereignty. Bionis said a signed agreement between NFP and Stanford Labau Labs stipulates that data generated from tribal samples belong to the tribe and that tribes will be included as co-authors and budgeted partners on follow-on grants. "Because of AB 389, the data belongs to the tribe," he said. "That means tribes control the narrative and ownership of the results." He described a second template agreement to be used between NFP and individual tribes so each tribe retains ownership of its data.

Technical experts in the Q&A urged caution about analytical limits. Teresa, from the Metropolitan Water District of Southern California, noted that measuring micro- and nanoplastics in drinking water is analytically challenging, often requiring large sample volumes and strict contamination controls. "Drinking-water treatment does remove particles," she said, "and you typically need large volumes and rigorous quality control to be confident in results." Bionis and Stanford participants agreed that methods are still evolving and that the lab took nearly two years to refine its procedures.

Bionis described next steps that include expanding the monitoring network with tribally led sampling across multiple sites, building concentration maps (for example, particles per unit of rainfall), and beginning ethically governed human testing focused on urine samples (noting blood testing presents high analytical interference). He invited volunteer participants, said stipends would be offered for consented volunteers, and listed the NFP website and contact email for sign-ups.

Organizers noted the webinar will be posted on the Water Quality Monitoring Council YouTube page and that Bionis expects a signing ceremony at Stanford for the data-sovereignty agreement. Bionis and multiple participants asked to continue technical collaboration with state and regional partners, including CalRecycle, CalEPA programs, BioMonitoring California and EPA tribal liaisons.

The presentation highlighted early evidence of widespread environmental microplastics at the sampled sites and emphasized two parallel priorities: improve and standardize laboratory methods, and ensure tribal control of data and authorship as the program scales. The project remains in pilot stage and Bionis said results beyond presence/absence will be reported after further replication and QA/QC.