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Microplastic ingestion was reported for common bottlenose dolphins (Tursiops truncatus) inhabiting Sarasota Bay, FL, USA, a community that also has prevalent exposure to plasticizers (i.e., phthalates) at concentrations higher than human reference populations. Exposure sources are currently unknown, but plastic-contaminated prey could be a vector. To explore the potential for trophic exposure, prey fish muscle and gastrointestinal tract (GIT) tissues and contents were screened for suspected microplastics, and particle properties (e.g., color, shape, surface texture) were compared with those observed in gastric samples from free-ranging dolphins. Twenty-nine fish across four species (hardhead catfish, Ariopsis felis; pigfish, Orthopristis chrysoptera; pinfish, Lagodon rhomboides; and Gulf toadfish, Opsanus beta) were collected from Sarasota Bay during September 2022. Overall, 97% of fish (n = 28) had suspected microplastics, and GIT abundance was higher than muscle. Fish and dolphin samples contained fibers and films; however, foams were common in dolphin samples and not observed in fish. Suspected tire wear particles (TWPs) were not in dolphin samples, but 23.1% and 32.0% of fish muscle and GIT samples, respectively, contained at least one suspected TWP. While some similarities in particles were shared between dolphins and fish, small sample sizes and incongruent findings for foams and TWPs suggest further investigation is warranted to understand trophic transfer potential.

Abstract Objectives Non‐fatal drownings confer significant morbidity and mortality in the United States. Chest radiograph (CXR) is typically used as a screening modality for interstitial edema but lacks sensitivity early after submersion. No study has evaluated lung ultrasound in assessing for pulmonary edema after submersion events and we hypothesized that lung point‐of‐care (POC) ultrasound can identify interstitial edema in patients presenting after non‐fatal drownings. Methods Patients presenting to the emergency department after a submersion event were eligible if a CXR was obtained as part of their care. Emergency medicine residents performed a lung POC ultrasound and provided a “novice” interpretation of “normal” or “abnormal,” which was independently reviewed by a blinded expert sonographer. Patients were contacted 2 weeks after presentation to assess for late sequela. Results A prospective convenience sample of 59 patients included 21 adults (36%) and 38 children (64%) enrolled over 17 months with a median age of 6. Twenty‐four (41%) patients had abnormalities on CXR. Of these, 20 patients had a positive ultrasound per novice interpretation. Compared to CXR, ultrasound had an overall sensitivity of 83% and a specificity of 66% for detecting pulmonary edema in non‐fatal drownings. Notably, out of 35 subjects with a negative CXR, there were 12 (34%) cases with a positive lung ultrasound, 10 of which required hospital admission. Conclusion Lung POC ultrasound has a moderate sensitivity and specificity when performed by novice sonographers to detect pulmonary edema presenting to an ED setting after a non‐fatal drowning event.

Phthalates are endocrine-disrupting chemicals added to plastics, personal care products, cleaning solutions, and pesticides. Extensive use has led to its exposure to wildlife, including common bottlenose dolphins (Tursiops truncatus) from Sarasota Bay, Florida, USA; however, there are gaps in knowledge regarding whether sample timing or geographic location influence exposure. Dolphins were evaluated for temporal and spatial variability in urinary mono(2-ethylhexyl) phthalate (MEHP) detection (2010–2019). Significant fluctuations in detectable MEHP concentrations were found across the dataset. All samples from 2014 and 2015 (n = 12) had detectable MEHP concentrations; thus, data were classified into cohorts to explore the significance of prevalent MEHP detection (“Cohort 1” (n = 10; 2010–2013), “Cohort 2” (2014–2015), and “Cohort 3” (n = 29; 2016–2019)). Compared to Cohorts 1 and 3, Cohort 2 had higher detectable MEHP concentrations (Dunn’s; p = 0.0065 and p = 0.0012, respectively) and a greater proportion of detectable MEHP concentrations (pairwise comparisons using Benjamini–Hochberg adjustments: p = 0.0016 and p = 0.0059, respectively). MEHP detection also varied across spatial scales. Dolphins with detectable MEHP concentrations had ranges primarily within enclosed embayments, while dolphins with nondetectable MEHP concentrations extended into open waters, potentially indicating geographically linked exposure risk. This study suggests that researchers and management agencies should consider a population’s ranging pattern, geographic habitat characteristics, and sample timing when assessing small cetacean health in relation to contaminant exposure.

The oceans contain trillions of plastic particles, mostly microplastics (i.e., particles < 5 mm diameter; 92.4% of plastic particles), which have been detected in organisms at all levels of the marine food web. The ubiquity of marine plastic debris has created a monumental environmental pollution problem with extensive public health consequences, as more than 40% of the world’s population lives near the coast and shares coastal resources. For decades, common bottlenose dolphins (Tursiops truncatus) have been used as sentinels of marine pollution risks for coastal communities that rely on seafood. Recently, prevalent phthalate exposure was documented in bottlenose dolphins residing in Sarasota Bay, FL, at concentrations exceeding those of human reference populations. While the source of their exposure is uncertain, the types of compounds detected suggest a plastic origin. The objective of this study was to screen for plastic ingestion among free-ranging dolphins in Sarasota Bay using gastric samples collected during catch-and-release health assessments. Gastric samples were collected from seven live bottlenose dolphins in 2019, and suspected microplastic particles were detected in all samples. The number of particles per sample ranged from 100, and the most common types were transparent films and white foams. Similar to other marine mammal studies, fibers were also present. Given that dolphins are likely exposed to microplastics via contaminated prey, findings from this and additional studies will help to evaluate the potential of contaminated seafood as an additional source of microplastic exposure for humans, as well as help to inform intervention and risk communication needs regarding seafood safety.

Abstract Phthalates are chemical additives to common consumer goods including cleaning products, cosmetics, personal care products, and plastic. Because they are not chemically bound to these products and are widely used, the potential for environmental contamination is significant. Phthalates and their metabolites have been associated with endocrine disruption and reproductive impairment, among other adverse health effects, in laboratory animals and human epidemiologic studies. Common bottlenose dolphins (Tursiops truncatus) are vulnerable to environmental pollutants due to their apex position in the food chain, long life spans, and habitat overlap with developed coastal areas. The objective of this study was to quantify phthalate metabolite concentrations in urine collected from bottlenose dolphins in Sarasota Bay, Florida, during May 2016 (n = 7) and May 2017 (n = 10). Screening of nine phthalate monoester metabolites in bottlenose dolphin urine was performed by liquid chromatography tandem mass spectrometry using methods adapted from those used for analyzing human samples. At least one phthalate metabolite was detected in 71% of the dolphins sampled across both years, with the highest concentrations detected for monoethyl phthalate (MEP; GM = 5.4 ng/ml; 95%CI: 1.3–22.0 ng/ml) and mono‐(2‐ethylhexyl) phthalate (MEHP; GM = 1.9 ng/ml; 95%CI: 1.1–3.2 ng/ml). These data demonstrate exposure to two of the most commonly used phthalates in commercial manufacturing, diethyl phthalate (DEP) and di‐2‐ethylhexyl phthalate (DEHP). This study establishes methods for urinary detection of phthalate metabolites in marine mammals and provides baseline data to address a significant and growing, yet poorly understood, health threat to marine wildlife.

Phthalates are chemical esters used to enhance desirable properties of plastics, personal care, and cleaning products. Phthalates have shown ubiquitous environmental contamination due to their abundant use and propensity to leach from products to which they are added. Following exposure, phthalates are rapidly metabolized and excreted through urine. Common bottlenose dolphins (Tursiops truncatus) sampled from Sarasota Bay, Florida, have demonstrated prevalent di(2-ethylhexyl) phthalate (DEHP) exposure indicated by detectable urinary mono(2-ethylhexyl) phthalate (MEHP) concentrations. Widespread exposure is concerning due to evidence of endocrine disruption from human and laboratory studies. To better understand how phthalate exposure may impact dolphin health, correlations between relevant hormone levels and detectable urinary MEHP concentrations were examined. Hormone concentrations measured via blood serum samples included triiodothyronine (T3), total thyroxine (T4), and free thyroxine (FT4). Urinary MEHP concentrations were detected in 56% of sampled individuals (n = 50; mean = 8.13 ng/mL; s.d. = 15.99 ng/mL). Adult female and male FT4 was significantly correlated with urinary MEHP concentrations (adult female Kendall’s tau = 0.36, p = 0.04; adult male Kendall’s tau = 0.42, p = 0.02). Evidence from this study suggests DEHP exposure may be impacting thyroid hormone homeostasis. Cumulative effects of other stressors and resultant endocrine impacts are unknown. Further research is warranted to understand potential health implications associated with this relationship.

Phthalates are chemical esters used as additives in common consumer goods, such as plastics, household cleaners, and personal care products. Phthalates are not chemically bound to the items to which they are added and can easily leach into the surrounding environment. Anthropogenic drivers, such as coastal plastic pollution and wastewater runoff, increase the exposure potential for coastal marine fauna. Phthalate exposure in free-ranging bottlenose dolphins has been the focus of recent study, with indications of heightened exposure to certain phthalate compounds. The objective of this study was to compare urinary phthalate metabolite concentrations among bottlenose dolphins (Tursiops truncatus) sampled in Sarasota Bay, FL, to levels reported in human samples collected as part of the Centers for Disease Control and Prevention's (CDC) National Health and Nutrition Examination Survey (NHANES). Monoethyl phthalate (MEP) and mono-(2-ethylhexyl) phthalate (MEHP) were the most prevalent metabolites detected in dolphin urine (n = 51; MEP = 29.41%; MEHP = 54.90%). The geometric mean (GM) concentration of MEP was significantly lower for dolphins (GM = 4.51 ng/mL; 95% CI: 2.77-7.34 ng/mL) compared to humans (p