Modeling work underway for study probing relationship between HF183 and illness risk

SCCWRP and its partners have begun working to model the levels at which exposure to the fecal contamination marker HF183 in wet-weather runoff is associated with increased illness risks for humans – the culmination of a four-year study aiming to increase the management utility of HF183.

Researchers’ initial health risk modeling work was presented in December to the Southern California Stormwater Monitoring Coalition (SMC), which is overseeing the study. Final results are expected to be published in summer 2024.

Although HF183 is widely used as a management tool for detecting human sources of fecal contamination in aquatic environments, no health thresholds have been developed to date that explain illness risks for beachgoers and other people who may inadvertently ingest fecal contamination that comes from wet-weather runoff.

Researchers, who began the study by collecting field data across two wet-weather seasons, have since transitioned to using the data to develop an HF183 health risk model that can predict how many humans will get sick after exposure to runoff that is contaminated with a given level of HF183.