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1.
Sci Total Environ ; 880: 163302, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37031936

ABSTRACT

This is the first comprehensive study of per- and polyfluoroalkyl substances (PFAS) in a coastal food web of the U.S. North Atlantic, in which we characterize the presence and concentrations of 24 targeted PFAS across 18 marine species from Narragansett Bay, Rhode Island, and surrounding waters. These species reflect the diversity of a typical North Atlantic Ocean food web with organisms from a variety of taxa, habitat types, and feeding guilds. Many of these organisms have no previously reported information on PFAS tissue concentrations. We found significant relationships of PFAS concentrations with respect to various ecological characteristics including species, body size, habitat, feeding guild, and location of collection. Based upon the 19 PFAS detected in the study (5 were not detected in samples), benthic omnivores (American lobsters = 10.5 ng/g ww, winter skates = 5.77 ng/g ww, Cancer crabs = 4.59 ng/g ww) and pelagic piscivores (striped bass = 8.50 ng/g ww, bluefish = 4.30 ng/g ww) demonstrated the greatest average ∑PFAS concentrations across all species sampled. Further, American lobsters had the highest concentrations detected in individuals (∑PFAS up to 21.1 ng/g ww, which consisted primarily of long-chain PFCAs). The calculation of field-based trophic magnification factors (TMFs) for the top 8 detected PFAS determined that perfluorodecanoic acid (PFDA), perfluorooctane sulfonic acid (PFOS), and perfluorooctane sulfonamide (FOSA) associated with the pelagic habitat biomagnified, whereas perfluorotetradecanoic acid (PFTeDA) associated with the benthic habitat demonstrated trophic dilution in this food web (calculated trophic levels ranged from 1.65 to 4.97). While PFAS exposure to these organisms may have adverse implications for ecological impacts via toxicological effects, many of these species are also key recreational and commercial fisheries resulting in potential for human exposure via dietary consumption.


Subject(s)
Alkanesulfonic Acids , Bass , Fluorocarbons , Water Pollutants, Chemical , Animals , Humans , Food Chain , Environmental Monitoring , Fluorocarbons/analysis , Alkanesulfonic Acids/analysis , Water Pollutants, Chemical/analysis
2.
Teach Learn Med ; 34(5): 504-513, 2022.
Article in English | MEDLINE | ID: mdl-34763586

ABSTRACT

PROBLEM: Medical school can be a socially isolating experience, particularly for students underrepresented in medicine. Social isolation and perceptions of not belonging can negatively impact students' academic performance and well-being. Therefore, interventions are needed to support students and these efforts should be appealing, brief, and low-burden. INTERVENTION: Guided by evidence-based approaches, we developed the Build & Belong intervention for medical students as a brief peer-to-peer approach that consisted of four components. First, M3 and M4 students wrote reflections on belonging in medical school. Second, M3 and M4 students video recorded messages for M1 and M2 students using their written reflections. Third, M1 and M2 students watched and discussed the videos in small groups. Fourth, the M1 and M2 students wrote letters to future students. Our intervention differs from previous student belonging interventions in the peer delivery of messages. CONTEXT: The Build & Belong intervention aimed to improve medical students' social belongingness. Using a longitudinal observational study design, the intervention was piloted at a medical school in the Mid-Atlantic United States in 2017-2018. Students completed surveys before and after the intervention. Paired samples tests (t-tests and Wilcoxon) assessed pre- to post-intervention changes in social isolation, social connectedness, and social assurance. IMPACT: Among 63 medical students, with 25.9% from backgrounds underrepresented in medicine, we assessed follow-up outcomes in 38 students. Social isolation scores significantly decreased from baseline (M = 54.8, SD = 7.06) to follow-up (M = 51.3, SD = 6.67; p < .001). Social isolation changes were evident regardless of sex, although males reported a greater reduction (M Δ = -5.32, p < .001) than females (M Δ = -2.79, p = .014). Black/African American students had the largest reduction in social isolation (M Δ = -7.24, p = .010). Social assurance and connectedness scores did not change significantly between baseline and follow-up. Medical students appeared to resonate with messages delivered by more experienced peers (M3s and M4s), particularly messages that normalized feelings of not belonging and strategies to reduce those feelings. LESSONS LEARNED: The Build & Belong intervention appears to reduce social isolation scores among medical students. This pilot test of the Build & Belong intervention provides initial evidence of the effectiveness of a brief, low-cost intervention. Build & Belong may provide a scalable strategy to reduce medical students' social isolation. Our peer-based approach is distinct from administrator-led strategies; peers were seen as trusted and reliable sources of information about belonging and ways to overcome the challenges experienced during medical school.


Subject(s)
Students, Medical , Male , Female , Humans , Peer Group , Schools, Medical , Social Isolation , Trust
3.
Estuaries Coast ; 44(5): 1320-1343, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34149332

ABSTRACT

The blue crab, Callinectes sapidus, has a broad geographic distribution encompassing coastal waters of the eastern United States and Gulf of Mexico, but intraspecific patterns of habitat use and quality are lacking at northern latitudes. This study examined the population structure of blue crabs in the Seekonk and Taunton Rivers (Rhode Island and Massachusetts, USA): two tidally influenced rivers contiguous with the Narragansett Bay Estuary and dominated by shallow-water, unvegetated habitats. Crabs were collected fortnightly from May through August (2012-2016), and abundance- and growth-based metrics were used to assess riverine habitat use and quality. These metrics were also analyzed with respect to crab life history traits and in situ abiotic conditions to elucidate patterns of habitat selection throughout ontogeny. Crabs measuring 8 to 185 mm carapace width (CW; n = 2,577) were collected, and two distinct age-classes occupied the rivers during the spring and summer (maximum abundance ~ 5 crabs/10 m2). The younger age-0+ cohort was numerically dominant (~ 88% of total catch) and comprised of male and juvenile female crabs (mean ± SD abundance = 0.28 ± 0.26 males/10 m2 and 0.14 ± 0.12 juvenile females/10 m2). Males accounted for the majority of age-1+ crabs (~ 83% of cohort), yet sexually mature females were also observed (9% of cohort; mean ± SD abundance = 0.04 ± 0.06 adult females/100 m2; size at 50% maturity ± 95 CI = 129.0 ± 0.2 mm CW). Crabs were spatially segregated along a salinity gradient with males and juvenile females prevalent in oligohaline waters (upper river salinity ~ 5 ppt) and adult females mainly concentrating in higher salinity areas (mid- and lower river salinity ~ 11-21 ppt). Seasonal and interannual patterns in crab abundance also differed by sex and ontogeny. Peak catches of males and juvenile females occurred during the spring and mid-summer, and annual abundances were positively related to dissolved oxygen (DO) concentrations. In contrast, mature females were most abundant during August and years with elevated water temperatures. The absolute and relative growth rates of juvenile crabs equaled 0.9 ± 0.3 mm CW/day and 1.5 ± 0.6 % CW/day, respectively, and were directly related to DO levels. A synoptic examination of crab abundance and growth across a broad geographic range indicated that shallow-water, unvegetated habitats presently serve as functional nurseries in southern New England tidal rivers.

5.
Mar Pollut Bull ; 126: 166-178, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29421084

ABSTRACT

Total mercury (Hg; ppm dry weight) was measured in blue crabs, Callinectes sapidus, collected from Narraganset Bay and adjacent coastal lagoons and tidal rivers (Rhode Island/Massachusetts, USA) from May to August 2006-2016. For juvenile crabs (21-79mm carapace width, CW), total Hg was significantly greater in chelae muscle tissue (mean±1 SD=0.32±0.21ppm; n=65) relative to whole bodies (0.21±0.16ppm; n=19), and irrespective of tissue-type, crab Hg was positively related to CW indicating bioaccumulation of the toxicant. Across a broader range of crab sizes (43-185mm CW; n=465), muscle Hg concentrations were significantly higher in crabs from the Taunton River relative to other locations (0.71±0.35ppm and 0.20±0.10ppm, respectively). Spatial variations in crab Hg dynamics were attributed to habitat-specific Hg burdens of their prey, including bivalves, gastropods, polychaetes, and shrimp. Prey Hg, in turn, was directly related to localized sediment Hg and methylmercury conditions. Biota-sediment accumulation factors for crabs and prey were negatively correlated with sediment organic content, verifying that organically-enriched substrates reduce Hg bioavailability. From a human health perspective, frequent consumption of crabs from the Taunton River may pose a human health risk (23% of legal-size crabs exceeded US EPA threshold level); thus justifying spatially-explicit Hg advisories for this species.


Subject(s)
Brachyura/chemistry , Food Contamination/analysis , Mercury/analysis , Methylmercury Compounds/analysis , Water Pollutants, Chemical/analysis , Animals , Bivalvia , Body Size , Diet , Ecosystem , Fisheries , Food Chain , Geologic Sediments/chemistry , Humans , Massachusetts , Muscles/chemistry , New England , Rhode Island , Rivers , Sex Factors
6.
Mar Pollut Bull ; 114(1): 144-156, 2017 Jan 15.
Article in English | MEDLINE | ID: mdl-27595617

ABSTRACT

Total mercury (Hg) was measured in coastal fishes from Southern New England (RI, USA), and Hg exposure was estimated for anglers and family members that consumed these resources. Fish Hg was positively related to total length (n = 2028 across 7 fish species), and interspecies differences were evident among legally harvestable fish. Many recreational anglers and their families experienced excessively high Hg exposure rates, which was attributed to the enriched Hg content of frequently consumed fishes. Specifically, 51.5% of participants in this study had Hg exposures exceeding the US EPA reference dose, including 50.0% of women of childbearing years. These results are noteworthy given that Hg neurotoxicity occurs in adults and children from direct and prenatal low-dose exposure. Moreover, this study underscores the need for geographic-specific research that accounts for small-scale spatial variations in fish Hg and dietary habits of at-risk human populations.


Subject(s)
Diet/statistics & numerical data , Environmental Exposure/statistics & numerical data , Fisheries/statistics & numerical data , Mercury/metabolism , Water Pollutants, Chemical/metabolism , Water Pollution, Chemical/statistics & numerical data , Adult , Animals , Child , Feeding Behavior , Female , Fishes , Food Contamination/analysis , Humans , Male , Mercury/analysis , New England , Recreation , Water Pollutants, Chemical/analysis
7.
Estuaries Coast ; 39(5): 1505-1525, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27746705

ABSTRACT

This study evaluated the relative importance of the N arragansett Bay estuary (RI and MA, USA), and associated tidal rivers and coastal lagoons, as nurseries for juvenile winter flounder, Pseudopleuronectes americanus, and summer flounder, Paralichthys dentatus. Winter flounder (WF) and summer flounder (SF) abundance and growth were measured from May to October (2009-2013) and served as indicators for the use and quality of shallow-water habitats (water depth < 1.5-3.0 m). These bioindicators were then analyzed with respect to physiochemical conditions to determine the mechanisms underlying intra-specific habitat selection. WF and SF abundances were greatest in late May and June (maximum monthly mean = 4.9 and 0.55 flounder/m2 for WF and SF, respectively), and were significantly higher in the tidal rivers relative to the bay and lagoons. Habitat-related patterns in WF and SF abundance were primarily governed by their preferences for oligohaline (0.1-5 ppt) and mesohaline (6-18 ppt) waters, but also their respective avoidance of hypoxic conditions (< 4 mg DO/L) and warm water temperatures (> 25 °C). Flounder habitat usage was also positively related to sediment organic content, which may be due to these substrates having sufficiently high prey densities. WF growth rates (mean = 0.25 ± 0.14 mm/d) were negatively correlated with the abundance of conspecifics, whereas SF growth (mean = 1.39 ± 0.46 mm/d) was positively related to temperature and salinity. Also, contrary to expectations, flounder occupied habitats that offered no ostensible advantage in intra-specific growth rates. WF and SF exposed to low salinities in certain rivers likely experienced increased osmoregulatory costs, thereby reducing energy for somatic growth. Low-salinity habitats, however, may benefit flounder by providing refugia from predation or reduced competition with other estuarine fishes and macro-invertebrates. Examining WF and SF abundance and growth across each species' broader geographic distribution revealed that southern New England habitats may constitute functionally significant nurseries. These results also indicated that juvenile SF have a geographic range extending further north than previously recognized.

8.
Mar Environ Res ; 101: 124-134, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25440782

ABSTRACT

Trophic pathways and size-based bioaccumulation rates of total mercury were evaluated among recreationally caught albacore tuna (Thunnus alalunga), yellowfin tuna (Thunnus albacares), shortfin mako shark (Isurus oxyrinchus), thresher shark (Alopias vulpinus), and dolphinfish (Coryphaena hippurus) from offshore southern New England waters of the northwest Atlantic Ocean between 2008 and 2011. Mercury concentrations were highest in mako (2.65 ± 1.16 ppm) and thresher sharks (0.87 ± 0.71 ppm), and significantly lower in teleosts (albacore, 0.45 ± 0.14 ppm; yellowfin, 0.32 ± 0.09 ppm; dolphinfish, 0.20 ± 0.17 ppm). The relationship between body size and mercury concentration was positive and linear for tunas, and positive and exponential for sharks and dolphinfish. Mercury increased exponentially with δ (15)N values, a proxy for trophic position, across all species. Results demonstrate mercury levels are positively related to size, diet and trophic position in sharks, tunas, and dolphinfish, and the majority of fishes exhibited concentrations greater than the US EPA recommended limit.


Subject(s)
Food Chain , Mercury/metabolism , Sharks/metabolism , Tuna/metabolism , Water Pollutants, Chemical/metabolism , Animals , Atlantic Ocean , Body Size , Predatory Behavior
9.
Mar Environ Res ; 99: 20-33, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25081850

ABSTRACT

This study examined total mercury (Hg) concentrations in cartilaginous fishes from Southern New England coastal waters, including smooth dogfish (Mustelus canis), spiny dogfish (Squalus acanthias), little skate (Leucoraja erinacea), and winter skate (Leucoraja ocellata). Total Hg in dogfish and skates were positively related to their respective body size and age, indicating Hg bioaccumulation in muscle tissue. There were also significant inter-species differences in Hg levels (mean ± 1 SD, mg Hg/kg dry weight, ppm): smooth dogfish (3.3 ± 2.1 ppm; n = 54) > spiny dogfish (1.1 ± 0.7 ppm; n = 124) > little skate (0.4 ± 0.3 ppm; n = 173) âˆ¼ winter skate (0.3 ± 0.2 ppm; n = 148). The increased Hg content of smooth dogfish was attributed to its upper trophic level status, determined by stable nitrogen (δ(15)N) isotope analysis (mean δ(15)N = 13.2 ± 0.7‰), and the consumption of high Hg prey, most notably cancer crabs (0.10 ppm). Spiny dogfish had depleted δ(15)N signatures (11.6 ± 0.8‰), yet demonstrated a moderate level of contamination by foraging on pelagic prey with a range of Hg concentrations, e.g., in order of dietary importance, butterfish (Hg = 0.06 ppm), longfin squid (0.17 ppm), and scup (0.11 ppm). Skates were low trophic level consumers (δ(15)N = 11.9-12.0‰) and fed mainly on amphipods, small decapods, and polychaetes with low Hg concentrations (0.05-0.09 ppm). Intra-specific Hg concentrations were directly related to δ(15)N and carbon (δ(13)C) isotope signatures, suggesting that Hg biomagnifies across successive trophic levels and foraging in the benthic trophic pathway increases Hg exposure. From a human health perspective, 87% of smooth dogfish, 32% of spiny dogfish, and <2% of skates had Hg concentrations exceeding the US Environmental Protection Agency threshold level (0.3 ppm wet weight). These results indicate that frequent consumption of smooth dogfish and spiny dogfish may adversely affect human health, whereas skates present minimal risk.


Subject(s)
Dogfish/metabolism , Environmental Monitoring/statistics & numerical data , Food Chain , Food Contamination/analysis , Mercury/pharmacokinetics , Skates, Fish/metabolism , Water Pollutants, Chemical/pharmacokinetics , Animals , Atlantic Ocean , Mercury/analysis , New England , Nitrogen Isotopes/analysis , Species Specificity , Water Pollutants, Chemical/analysis
10.
AORN J ; 100(1): 8-26, 27-9, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24973182

ABSTRACT

The personal leadership of the perioperative director is a critical factor in the success of any change management initiative. This article presents an approach to perioperative nursing leadership that addresses obstacles that prevent surgical departments from achieving high performance in clinical and financial outcomes. This leadership approach consists of specific insights, priorities, and tools: key insights include self-understanding of personal barriers to leadership and accuracy at understanding economic and strategic considerations related to the OR environment; key priorities include creating a customer-centered organization, focusing on process improvement, and concentrating on culture change; and key tools include using techniques (e.g., direct engagement, collaborative leadership) to align surgical organizations with leadership priorities and mitigate specific perioperative management risks. Included in this article is a leadership development plan for perioperative directors.


Subject(s)
Leadership , Outcome and Process Assessment, Health Care , Perioperative Nursing/organization & administration , Humans , Operating Room Nursing/organization & administration , Operating Rooms/organization & administration , Organizational Culture , Organizational Innovation , Patient Care Team/organization & administration , Postoperative Care/standards , Quality Improvement , Surgeons
11.
Arch Environ Contam Toxicol ; 65(4): 715-23, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23929385

ABSTRACT

Caudal fin clips and dorsolateral scales were analyzed as a potential nonlethal approach for predicting muscle tissue mercury (Hg) concentrations in marine fish. Target fish were collected from the Narragansett Bay (Rhode Island, USA) and included black sea bass Centropristis striata [n = 54, 14-55 cm total length (TL)], bluefish Pomatomus saltatrix (n = 113, 31-73 cm TL), striped bass Morone saxatilis (n = 40, 34-102 cm TL), summer flounder Paralichthys dentatus (n = 64, 18-55 cm TL), and tautog Tautoga onitis (n = 102, 27-61 cm TL). For all fish species, Hg concentrations were greatest in muscle tissue [mean muscle Hg = 0.47-1.18 mg/kg dry weight (dw)] followed by fin clips (0.03-0.09 mg/kg dw) and scales (0.01-0.07 mg/kg dw). The coefficient of determination (R (2)) derived from power regressions of intraspecies muscle Hg against fin and scale Hg ranged between 0.35 and 0.78 (mean R (2) = 0.57) and 0.14-0.37 (mean R (2) = 0.30), respectively. The inclusion of fish body size interaction effects in the regression models improved the predictive ability of fins (R (2) = 0.63-0.80; mean = 0.71) and scales (R (2) = 0.33-0.71; mean = 0.53). According to the high level of uncertainty within the regression models (R (2) values) and confidence interval widths, scale analysis was deemed an ineffective tool for estimating muscle tissue Hg concentrations in the target species. In contrast, the examination of fin clips as predictors of muscle Hg had value as a cursory screening tool; however, this method should not be the foundation for developing human consumption advisories. It is also noteworthy that the efficacy of these nonlethal techniques was highly variable across fishes and likely depends on species-specific life-history characteristics.


Subject(s)
Environmental Monitoring/methods , Fishes/metabolism , Mercury/metabolism , Water Pollutants, Chemical/metabolism , Animals
12.
Mar Pollut Bull ; 64(4): 807-19, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22317792

ABSTRACT

Total mercury (Hg) and methylmercury (MeHg) were analyzed in near surface sediments (0-2 cm) and biota (zooplankton, macro-invertebrates, finfish) collected from Narragansett Bay (Rhode Island/Massachusetts, USA) and adjacent embayments and tidal rivers. Spatial patterns in sediment contamination were governed by the high affinity of Hg for total organic carbon (TOC). Sediment MeHg and percent MeHg were also inversely related to summer bottom water dissolved oxygen (DO) concentrations, presumably due to the increased activity of methylating bacteria. For biota, Hg accumulation was influenced by inter-specific habitat preferences and trophic structure, and sediments with high TOC and percent silt-clay composition limited mercury bioavailability. Moreover, hypoxic bottom water limited Hg bioaccumulation, which is possibly mediated by a reduction in biotic foraging, and thus, dietary uptake of mercury. Finally, most biota demonstrated a significant positive relationship between tissue and TOC-normalized sediment Hg, but relationships were much weaker or absent for sediment MeHg. These results have important implications for the utility of estuarine biota as subjects for mercury monitoring programs.


Subject(s)
Ecosystem , Environmental Monitoring , Geologic Sediments/chemistry , Mercury/analysis , Water Pollutants, Chemical/analysis , Animals , Fundulidae/physiology , Invertebrates/chemistry , Methylmercury Compounds/analysis , New England , Oxygen/analysis , Seawater/chemistry , Zooplankton/chemistry
13.
Environ Toxicol Chem ; 30(6): 1447-58, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21381087

ABSTRACT

In this study, bluefish (Pomatomus saltatrix; age 0-7, n = 632) and their prey (forage fish, macroinvertebrates, zooplankton; n = 2,005) were collected from the Narragansett Bay estuary (RI, USA), and total Hg concentration was measured in white muscle and whole-body tissues, respectively. Bluefish Hg concentrations were analyzed relative to fish length, prey Hg content, and ontogenetic shifts in habitat use and foraging ecology, the latter assessed using stomach content analysis (n = 711) and stable nitrogen (δ(15)N) and carbon (δ(13)C) isotope measurements (n = 360). Diet and δ(13)C analysis showed that age 0 bluefish consumed both benthic and pelagic prey (silversides, sand shrimp, planktonic crustaceans; δ(13)C = - 16.52‰), whereas age 1 + bluefish fed almost exclusively on pelagic forage fish (Atlantic menhaden, herring; δ(13)C = - 17.33‰). Bluefish total Hg concentrations were significantly correlated with length (mean Hg = 0.041 and 0.254 ppm wet wt for age 0 and age 1 + bluefish, respectively). Furthermore, Hg biomagnification rates were maximal during bluefish early life stages and decelerated over time, resulting in relatively high Hg concentrations in age 0 fish. Rapid Hg accumulation in age 0 bluefish is attributed to these individuals occupying a comparable trophic level to age 1 + bluefish (δ(15)N = 15.58 and 16.09‰; trophic level = 3.55 and 3.71 for age 0 and age 1 + bluefish, respectively), as well as juveniles having greater standardized consumption rates of Hg-contaminated prey. Finally, bluefish larger than 30 cm total length consistently had Hg levels above the U.S. Environmental Protection Agency criterion of 0.3 ppm. As such, frequent consumption of bluefish could pose a human health risk, and preferentially consuming smaller bluefish may be an inadequate strategy for minimizing human dietary exposure to Hg.


Subject(s)
Mercury/metabolism , Perciformes/metabolism , Water Pollutants, Chemical/metabolism , Animals , Biota , Diet/statistics & numerical data , Ecology , Ecosystem , Environmental Monitoring , Food Chain , Mercury/analysis , Muscles/metabolism , Rhode Island , Seawater/chemistry , Water Pollutants, Chemical/analysis , Water Pollution, Chemical/statistics & numerical data , Zooplankton/metabolism
14.
Arch Environ Contam Toxicol ; 58(2): 431-43, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19997909

ABSTRACT

The summer flounder Paralichthys dentatus and winter flounder Pseudopleuronectes americanus support valuable fisheries along the northeastern United States. The importance of these flatfish as a human dietary resource indicates they are potential sources of mercury (Hg) to fish-consuming citizens. In this study, summer flounder (SF) and winter flounder (WF) were collected from the Narragansett Bay (Rhode Island, USA) and were measured for total Hg burden in whole-body or dorsal muscle tissue. Interspecies differences in Hg contamination were analyzed relative to flounder body size, age, and Hg content of preferred prey. Stable isotope signatures were also used to elucidate the effect of trophic processes on Hg accumulation in the estuarine food web. The mean Hg content of SF exceeded concentrations measured in WF across multiple life-history stages (0.039-0.100 and 0.016-0.029 mg Hg/kg wet weight for SF and WF, respectively), and observed values for both species were lower than the US Environmental Protection Agency regulatory threshold of 0.3 mg Hg/kg wet weight. Total Hg concentrations were also positively correlated with flounder age and length, verifying that both flatfish bioaccumulate Hg. SF accumulate Hg at an accelerated rate, however, owing to this species consuming Hg-enriched prey (teleosts, squid, and macrocrustaceans; mean Hg content = 0.023 mg Hg/kg wet weight), whereas WF feed on prey with low Hg levels (amphipods and polychaetes; mean Hg content = 0.013 mg Hg/kg wet weight). The positive correlation observed between mean biota Hg content and stable nitrogen (delta(15)N) isotope signatures further indicates that Hg is trophically transferred through the food web, and higher trophic level organisms (i.e., enriched delta(15)N) have increased Hg concentrations. Therefore, results from this study suggest that dietary preference and trophic structure are the main factors affecting Hg bioaccumulation in the estuary. Total Hg concentrations of flatfish from the Narragansett Bay, however, do not necessarily reflect coastwide contamination patterns. This reinforces the importance of having research conducted at sufficiently small spatial scales, including the local assessment of Hg contamination for the purpose of issuing state consumption advisories.


Subject(s)
Animal Feed/analysis , Flounder/metabolism , Mercury Compounds/metabolism , Water Pollutants, Chemical/metabolism , Animals , Body Burden , Diet , Environmental Monitoring , Flounder/growth & development , Food Chain , Food Contamination/analysis , Mercury Compounds/analysis , Muscle, Skeletal/chemistry , Muscle, Skeletal/metabolism , Rhode Island , Rivers , Water Pollutants, Chemical/analysis
15.
Mar Environ Res ; 67(3): 117-28, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19150736

ABSTRACT

We examined the bioaccumulation and trophic transfer of mercury in two marine finfish species, striped bass (Morone saxatilis) and tautog (Tautoga onitis), collected from the Narragansett Bay (Rhode Island, USA). For each of these target fish, white muscle tissue was analyzed for total mercury (Hg) and results were evaluated relative to fish age, body size, and Hg content of preferred prey. Dietary and stable isotope analysis was also used to elucidate the effect of trophic processes on Hg concentrations in fish. The Hg content of muscle tissue was positively correlated with fish age and length for both species, although striped bass accumulated Hg faster than tautog. Accelerated Hg bioaccumulation in striped bass is consistent with its high trophic level (trophic level = 4.07) and Hg-enriched prey (forage fish and macrocrustaceans; mean Hg content = 0.03 mg Hg kg wet wt(-1)). In contrast, tautog maintain a lower trophic status (trophic level=3.51) and consume prey with lower Hg levels (mussels and crabs; mean Hg content = 0.02 mg Hg kg wet wt(-1)). Despite differences in Hg bioaccumulation between target fish, the mean Hg concentration of tautog exceeded levels in striped bass (0.24 and 0.16 mg Hg kg wet wt(-1), respectively) due to a disparity in age-at-catch between sampled groups (mean age of tautog and bass = 11.3 and 4.3 yr, respectively). Taking into account legal minimum catch lengths further revealed that 75.0% of legal-size striped bass (>70.2 cm TL; n = 4) and 44.8% of tautog (> 40.6 cm TL; n = 29) had Hg levels beyond the US EPA regulatory threshold of 0.3 mg Hg kg wet wt(-1). Moreover, Hg-length relationships suggest that each target fish meets this threshold near their minimum legal catch length. Our findings reiterate the value of species ecology to improve predictions of fish Hg and permit better management of human contamination by this important dietary source.


Subject(s)
Bass/metabolism , Food Chain , Mercury/metabolism , Perciformes/metabolism , Water Pollutants, Chemical/metabolism , Animals , Diet , Gastrointestinal Contents , Muscle, Skeletal/metabolism , Nitrogen Isotopes/analysis , Oceans and Seas , Rhode Island
17.
Ecohealth ; 5(4): 426-41, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19294469

ABSTRACT

During the past century, anthropogenic activities have altered the distribution of mercury (Hg) on the earth's surface. The impacts of such alterations to the natural cycle of Hg can be minimized through coordinated management, policy decisions, and legislative regulations. An ability to quantitatively measure environmental Hg loadings and spatiotemporal trends of their fate in the environment is critical for science-based decision making. Here, we outline a Hg monitoring program for temperate estuarine and marine ecosystems on the Atlantic Coast of North America. This framework follows a similar, previously developed plan for freshwater and terrestrial ecosystems in the U.S. Methylmercury (MeHg) is the toxicologically relevant form of Hg, and its ability to bioaccumulate in organisms and biomagnify in food webs depends on numerous biological and physicochemical factors that affect its production, transport, and fate. Therefore, multiple indicators are needed to fully characterize potential changes of Hg loadings in the environment and MeHg bioaccumulation through the different marine food webs. In addition to a description of how to monitor environmental Hg loads for air, sediment, and water, we outline a species-specific matrix of biotic indicators that include shellfish and other invertebrates, fish, birds and mammals. Such a Hg monitoring template is applicable to coastal areas across the Northern Hemisphere and is transferable to arctic and tropical marine ecosystems. We believe that a comprehensive approach provides an ability to best detect spatiotemporal Hg trends for both human and ecological health, and concurrently identify food webs and species at greatest risk to MeHg toxicity.


Subject(s)
Ecosystem , Environmental Monitoring/methods , Mercury/analysis , Water Pollutants, Chemical/analysis , Animals , Atlantic Ocean , Birds , Fishes , Invertebrates , Mammals , North America
18.
AORN J ; 83(4): 834-8, 841-6; quiz 849-52, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16674027

ABSTRACT

Contracting a disease from bloodborne pathogens has been identified as an occupational hazard for perioperative personnel for more than two decades. Perioperative staff members are particularly vulnerable to percutaneous exposure. Despite known hazards, research has shown that perioperative staff members continue to take risks by not consistently complying with standard precautions and not reporting all percutaneous injuries. Health care workers (HCWs) and their employers need to work together to ensure that workplaces are safe. This article discusses mechanisms of bloodborne pathogen transmission, compliance with standard guidelines, and the social and economic costs of contracting a bloodborne illness. Steps to ensure that HCWs are protected also are outlined.


Subject(s)
Blood-Borne Pathogens , Infection Control/standards , Occupational Exposure/prevention & control , Operating Rooms/standards , Perioperative Nursing/standards , Guideline Adherence , HIV Infections/prevention & control , HIV Infections/transmission , Hepatitis B/prevention & control , Hepatitis B/transmission , Hepatitis C/prevention & control , Hepatitis C/transmission , Humans , Occupational Exposure/economics , Wounds, Penetrating/prevention & control
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