Proc Natl Acad Sci U S A
November 2024
Globally, ocean dumping of chemical waste is a common method of disposal and relies on the assumption that dilution, diffusion, and dispersion at ocean scales will mitigate human exposure and ecosystem impacts. In southern California, extensive dumping of agrochemical waste, particularly chlorinated hydrocarbon contaminants such as DDT, via sewage outfalls and permitted offshore barging occurred for most of the last century. This study compiled a database of existing sediment and fish DDT measurements to examine how this unique legacy of regional ocean disposal translates into the contemporary contamination of the coastal ocean.
View Article and Find Full Text PDFOutdoor defecation by people experiencing homelessness is frequently perceived as a potentially large source of human fecal pollution and a significant source of health risk in urban waterbodies with recreational contact. The goal of this study was to count the number of people experiencing homelessness and quantifies their sanitation habits in an urban river corridor setting, then use this information for estimating human fecal pollutant loading on a watershed scale. Two types of census counts were conducted including periodic point-in-time counts over six years and weekly counts of encampments.
View Article and Find Full Text PDFPrevious research with students and some professional groups (psychologists) has demonstrated that repeated feedback in simulated investigative interviews with computerized child avatars improves the quality of interviews conducted with real children who have witnessed a mock event. However, it is not known whether this type of training would improve the quality of investigative interviews with actual child victims and witnesses of physical and sexual abuse. Twenty-two police investigators participated in the study.
View Article and Find Full Text PDFBackground: Children may be at higher risk for swimming-associated illness following exposure to fecally-contaminated recreational waters. We analyzed a pooled data set of over 80,000 beachgoers from 13 beach sites across the United States to compare risks associated with the fecal indicator bacteria Enterococcus spp. (measured by colony forming units, CFU and quantitative polymerase chain reaction cell equivalents, qPCR CE) for different age groups across different exposures, sites and health endpoints.
View Article and Find Full Text PDFContamination in the coastal zone is closely linked to urbanization and has become a global issue. The coastal aquatic environment is the terminal sink for many chemicals; however, little is known about the occurrence and variation among habitats as well as integrative toxicity for pesticides, i.e.
View Article and Find Full Text PDFMarine recreational fisheries in California are economically and culturally important; however, consumption of contaminated seafood may be a human health risk. The California Environmental Protection Agency Office of Environmental Health Hazard Assessment developed Advisory Tissue Levels (ATLs) to be used in developing consumption recommendations protecting the health of fish consumers. This study characterizes extent and magnitude of bioaccumulation of contaminants in sport fish in Southern California relative to ATLs.
View Article and Find Full Text PDFIn 2017, the Trump Administration restored local law enforcement agencies' access to military weapons and some other types of surplus military equipment (SME) that had been prohibited by the Obama Administration. The Justice Department background paper used to justify this decision cited two papers published by the American Economic Association. These papers used SME data collected with a 2014 Freedom of Information Act request and concluded that SME, supplied to local law enforcement by the federal government via the 1033 Program, reduces crime.
View Article and Find Full Text PDFBioretention systems are widely used green infrastructure elements that utilize engineered bioretention soil media (BSM) for stormwater capture and treatment. Conventional bioretention soil media, which typically consists of sand, sandy loam, loamy sand or topsoil amended with compost, has limited capacity to remove and may leach some stormwater pollutants. Alternative engineered amendments, both organic and inorganic, have been tested to supplement BSM.
View Article and Find Full Text PDFThe continental shelf of southern California is an important location for the extraction of petroleum and natural gas. Many platforms in the region have been operating for more than four decades and are being targeted for decommissioning. Information on the condition of surrounding habitats to the platforms will be important for regulators.
View Article and Find Full Text PDFUrban beaches are frequently impacted from multiple sources of fecal contamination. This along with high beach usage underscores the importance of appropriate management that protects swimmer health. The USEPA has enabled the use of QMRA as a tool for quantifying swimmer health risk and setting site-specific water quality objectives.
View Article and Find Full Text PDFThe beach environment creates many barriers to effective sun protection, putting beachgoers at risk for sunburn, a well-established risk factor for skin cancer. Our objective was to estimate incidence of sunburn among beachgoers and evaluate the relationship between sunburn incidence and sun-protective behaviors. A secondary analysis, of prospective cohorts at 12 locations within the U.
View Article and Find Full Text PDFAlong southern California beaches, the concentrations of fecal indicator bacteria (FIB) used to quantify the potential presence of fecal contamination in coastal recreational waters have been previously documented to be higher during wet weather conditions (typically winter or spring) than those observed during summer dry weather conditions. FIB are used for management of recreational waters because measurement of the bacterial and viral pathogens that are the potential causes of illness in beachgoers exposed to stormwater can be expensive, time-consuming, and technically difficult. Here, we use droplet digital Polymerase Chain Reaction (digital PCR) and digital reverse transcriptase PCR (digital RT-PCR) assays for direct quantification of pathogenic viruses, pathogenic bacteria, and source-specific markers of fecal contamination in the stormwater discharges.
View Article and Find Full Text PDFSeabirds are often cited as sentinels of the marine environment, but are rarely used in traditional ocean and coastal contaminant monitoring. Four classes of persistent organic pollutants (POPs, n=68) and three trace elements (mercury, selenium, and arsenic) were measured in the eggs of California least terns (Sterna antillarum browni), caspian terns (Hydroprogne caspia), double-crested cormorants (Phalacrocorax auritus), and western gulls (Larus occidentalis) that nest in the Southern California Bight. Building on a periodic five year regional monitoring program, we measured contaminant exposure and assessed the utility of seabirds as regional contaminant biomonitors.
View Article and Find Full Text PDFWe modeled the risk of gastrointestinal (GI) illness associated with recreational exposures to marine water following storm events in San Diego County, California. We estimated GI illness risks via quantitative microbial risk assessment (QMRA) techniques by consolidating site specific pathogen monitoring data of stormwater, site specific dilution estimates, literature-based water ingestion data, and literature based pathogen dose-response and morbidity information. Our water quality results indicated that human sources of contamination contribute viral and bacterial pathogens to streams draining an urban watershed during wet weather that then enter the ocean and affect nearshore water quality.
View Article and Find Full Text PDFRainstorms increase levels of fecal indicator bacteria in urban coastal waters, but it is unknown whether exposure to seawater after rainstorms increases rates of acute illness. Our objective was to provide the first estimates of rates of acute illness after seawater exposure during both dry- and wet-weather periods and to determine the relationship between levels of indicator bacteria and illness among surfers, a population with a high potential for exposure after rain. We enrolled 654 surfers in San Diego, California, and followed them longitudinally during the 2013-2014 and 2014-2015 winters (33,377 days of observation, 10,081 surf sessions).
View Article and Find Full Text PDFBackground: Coliphages have been proposed as indicators of fecal contamination in recreational waters because they better mimic the persistence of pathogenic viruses in the environment and wastewater treatment than fecal indicator bacteria. We estimated the association between coliphages and gastrointestinal illness and compared it with the association with culturable enterococci.
Methods: We pooled data from six prospective cohort studies that enrolled coastal beachgoers in California, Alabama, and Rhode Island.
Introduction: Since 2008, the McMaster University Royal College Emergency Medicine residency training program has run practice Short Answer Question (SAQ) examinations to help residents test their knowledge and gain practice in answering exam-style questions. However, marking this type of SAQ exam is time-consuming.
Methods: To help address this problem, we require that senior residents help mark at least one exam per year alongside faculty members.
Objectives: To provide summary estimates of gastroenteritis risks and illness burden associated with recreational water exposure and determine whether children have higher risks and burden.
Methods: We combined individual participant data from 13 prospective cohorts at marine and freshwater beaches throughout the United States (n = 84 411). We measured incident outcomes within 10 days of exposure: diarrhea, gastrointestinal illness, missed daily activity (work, school, vacation), and medical visits.
Sci Total Environ
October 2016
The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration above 0.
View Article and Find Full Text PDFIntroduction: Advances in molecular methods provide new opportunities for directly measuring pathogens or host-associated markers of fecal pollution instead of relying on fecal indicator bacteria (FIB) alone for beach water quality monitoring. Adoption of new indicators depends on identifying relationships between either the presence or concentration of the indicators and illness among swimmers. Here we present results from three epidemiologic studies in which a broad range of bacterial and viral indicators of fecal contamination were measured simultaneously by either culture or molecular methods along with Enterococcus to assess whether they provide better health risk prediction than current microbial indicators of recreational water quality.
View Article and Find Full Text PDFWater Environ Res
September 2015
Marine protected areas worldwide limit harvest to protect sensitive fisheries, but rarely do they address water quality goals that may have equally demonstrable impacts. California has over 500 coastal shoreline miles of marine protected areas designated as Areas of Special Biological Significance (ASBS), but receives untreated wet weather runoff discharges from over 1600 storm drain outfalls. The goal of this study was to assess the extent and magnitude of water quality impacts in ASBS following storm events.
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