Relationships between indicators and pathogens in shellfish and water in Newport Bay, CA

摘要: In California, total and fecal coliform levels in the water column are currently used to evaluate the attainment of the shellfish harvesting (SHEL) beneficial use. The SHEL water quality objectives (WQO) for fecal coliform (FC), which are applicable to the Santa Ana region, and based on US FDA and National Shellfish Sanitation Program (NSSP) standards originally developed for fisheries on the US East Coast and Gulf of Mexico and adopted by California, require that monthly median fecal coliform counts in the water column do not exceed 14 MPN/100 mL and that no more than 10% of samples exceed 43 MPN FC/100 mL. These WQOs are far more difficult to meet than California’s REC-1 WQOs, and they apply to many marine and estuarine waters along the California coast. Although microbial water quality in Newport Bay has improved in recent years and often meets WQO’s for recreational use, many sites in the bay are out of compliance of the SHEL WQO, especially during the winter season. To date, there have been no locally published studies that evaluate the appropriateness of the current water quality objectives for SHEL. Although, it has been previously hypothesized that current water column-based FC WQO for SHEL may not be relevant for evaluating safety of recreationally harvested shellfish in local waters.This study aimed to examine the applicability of the current Newport Bay fecal coliform WQO for recreational shellfish harvesting in the dry season, when southern California experiences long periods with no precipitation. To this end, Pacific oysters were deployed at 12 sites within Newport Bay over a six-week period. Oysters were …