Martinez, CA - A toxicologist contracted by the County began collecting soil samples today from areas potentially exposed to metal-laden spent catalyst released by the Martinez Refining Company (MRC) during an incident last Thanksgiving. The sampling will assess the risks posed to human health from the release in neighborhoods surrounding the refinery, primarily in Martinez and Benicia.
The soil samples will be tested for concentrations of metals associated with the catalyst, which may pose health risks through skin contact, inhalation, or consumption of produce grown in contaminated soil. Lab results are expected to be available in late May or early June.
Supervisor Federal Glover, whose district includes the MRC-owned refinery, stated, "The community is eager to find out what's in the soil in their yards and whether they should be concerned for their health. The soil testing will help provide residents with answers to those questions."
The sampling plan was informed by a plume model map created by the Bay Area Air Quality Management District and was approved by the MRC Oversight Committee, which includes seven community residents. TRC, a Concord-based environmental consulting firm, is conducting the soil sampling and risk assessment for the County.
The incident occurred on November 24-25, 2022, when MRC accidentally released up to 24 tons of metal-laden spent catalyst dust into the surrounding community. The County learned about the incident through social media two days later, as MRC failed to provide proper notification. Initial wipe samples of the spent-catalyst dust taken from surfaces near the refinery revealed elevated levels of metals such as aluminum, barium, chromium, nickel, vanadium, and zinc.
While the most acute health risk occurred during the incident due to potential respiratory distress from inhaling the dust, concerns persist about long-term health impacts, particularly from consuming food grown in contaminated soil.
In March, the County's health officer issued an advisory cautioning residents not to eat food grown in potentially contaminated soil until environmental testing could be completed.
"Residents affected by this release deserve to know if there is any health risk. Contra Costa Health is working as quickly as possible to ensure that accurate information reaches the public about this issue," said Board of Supervisors Chair John Gioia, who also serves on the Bay Area Air Quality Management District Board of Directors.
For more information on the risk assessment and independent investigation of the November 2022 incident, visit cchealth.org/hazmat/mrc