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The influence of nutrient loading on methylmercury availability in Long Island estuaries 全文
2021
Estuaries provide critical habitat for food webs supporting fish and shellfish consumed by humans, but estuarine ecosystem health has been threatened by increases in nitrogen loading as well as inputs of the neurotoxin, mercury (Hg), which biomagnifies in food webs and poses risk to humans and wildlife. In this study, the effects of nutrient loading on the fate of Hg in shallow coastal estuaries were examined to evaluate if their interaction enhances or reduces Hg bioavailability in sediments, the water column, and concentrations in lower trophic level fish (Fundulus heteroclitus and Menidia menidia). Multiple sites were sampled within two human impacted coastal lagoons, Great South Bay (GSB) and Jamaica Bay (JB), on the southern coast of Long Island, NY, United States of America (U.S.A.). Carbon (C), nitrogen (N), sulfur (S), Hg, and methylmercury (MeHg) were measured in surface sediments and the water column, and total Hg (THg) was measured in two species of forage fish. Minimal differences were found in dissolved and particulate Hg, dissolved organic carbon (DOC), and salinity between the two bays. Across lagoons, concentrations of chlorophyll-a were correlated with total suspended solids (TSS), and water column THg and MeHg was largely associated with the particulate fraction. Methylmercury concentrations in particulates decreased with increasing TSS and chlorophyll-a, evidence of biomass dilution of MeHg with increasing productivity at the base of the food chain. Water column Hg was associated with THg concentrations in Atlantic silversides, while mummichog THg concentrations were related to sediment concentrations, reflecting their different feeding strategies. Finally, higher nutrient loading (lower C:N in sediments) while related to lower particulate concentrations coincided with higher bioaccumulation factors (BAF) for Hg in both fish species. Thus, in shallow coastal lagoons, increased nutrient loading resulted in decreased Hg concentrations at the base of the food web but resulted in greater bioaccumulation of Hg to fish relative to its availability in algal food.
显示更多 [+] 显示较少 [-]Occurrence and distribution of melamine and its derivatives in surface water, drinking water, precipitation, wastewater, and swimming pool water 全文
2020
Zhu, Hongkai | Kannan, Kurunthachalam
The extensive use of melamine and its three derivatives (i.e., ammeline, ammelide, and cyanuric acid) resulted in their widespread occurrence in the environment. Nevertheless, limited information is available on their distribution in the aquatic environment. In this study, concentrations and profiles of melamine and its derivatives were determined in 223 water samples, comprising river water, lake water, seawater, tap water, bottled water, rain water, wastewater, and swimming pool water, collected from New York State, USA. The sum concentrations of melamine and its derivatives (∑₄MELs) decreased in the following order: swimming pool water (median: 1.5 × 10⁷ ng/L) ≫ wastewater (1240) > precipitation (739) > tap water (512) > river water (370) > lake water (347) > seawater (186) > bottled water (98). Cyanuric acid was the major compound, accounting for 60–100% of ∑₄MELs concentrations in swimming pool water, wastewater, precipitation, tap water, seawater, and bottled water, whereas melamine dominated in river and lake water (54–64% of ∑₄MELs). Significant positive correlations (0.499 < R < 0.703, p < 0.002) were found between the concentrations of melamine and atrazine (a triazine herbicide) in surface waters. The geographic distribution in the concentrations of ∑₄MELs in river, lake, and tap water corresponded with the degree of urbanization, suggesting that human activities contribute to the sources melamine and cyanuric acid in the aquatic environments. A preliminary hazard assessment of melamine and cyanuric acid in waters suggested that their ecological or human health risks were minimal. This is the first study to document the occurrence and spatial distribution of melamine and its derivatives in waters from the United States.
显示更多 [+] 显示较少 [-]Trends of polychlorinated dioxins, polychlorinated furans, and dioxin-like polychlorinated biphenyls in Chinook and Coho salmonid eggs from a Great Lakes tributary 全文
2019
Garner, Andrew J. | Pagano, James J.
Eggs from mature Chinook (Oncorhynchus tshawytscha) and Coho (Oncorhynchus kisutch) salmon were collected between 2004 and 2014 from the Salmon River fish hatchery in Altmar, New York. The egg samples were analyzed for seventeen polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), as well as four dioxin-like polychlorinated biphenyls (DL-PCBs) using USEPA methods 1613 and 1668. Salmonid eggs were chosen as a tissue of interest since salmon feed at all trophic levels of the food web as they grow, and spawn in a narrow range of ages providing consistent, representative, and temporal samples of contaminant exposure. First-order decay models indicate decreasing trends for all select contaminants in both species, expressed by a toxic equivalence (TEQ) half-life (t₁/₂) of 11 years in Chinook and Coho eggs. No significant statistical difference in contaminant elimination rates were noted between species. TEQ elimination rates for Coho and Chinook eggs were not significantly different (p > 0.05) when compared with published Lake Ontario whole-fish lake trout elimination rates. Our research demonstrates that salmonid eggs are an effective means to assess PCDD, PCDF, and DL-PCB exposures and long-term trends in the Great Lakes.
显示更多 [+] 显示较少 [-]Microenvironmental air quality impact of a commercial-scale biomass heating system 全文
2017
Tong, Zheming | Yang, Bo | Hopke, Philip K. | Zhang, K Max
Initiatives to displace petroleum and climate change mitigation have driven a recent increase in space heating with biomass combustion. However, there is ample evidence that biomass combustion emits significant quantities of health damaging pollutants. We investigated the near-source micro-environmental air quality impact of a biomass-fueled combined heat and power system equipped with an electrostatic precipitator (ESP) in Syracuse, NY. Two rooftop sampling stations with PM2.5 and CO2 analyzers were established in such that one could capture the plume while the other one served as the background for comparison depending on the wind direction. Four sonic anemometers were deployed around the stack to quantify spatially and temporally resolved local wind patterns. Fuel-based emission factors were derived based on near-source measurement. The Comprehensive Turbulent Aerosol Dynamics and Gas Chemistry (CTAG) model was then applied to simulate the spatial variations of primary PM2.5 without ESP. Our analysis shows that the absence of ESP could lead to an almost 7 times increase in near-source primary PM2.5 concentrations with a maximum concentration above 100 μg m−3 at the building rooftop. The above-ground “hotspots” would pose potential health risks to building occupants since particles could penetrate indoors via infiltration, natural ventilation, and fresh air intakes on the rooftop of multiple buildings. Our results demonstrated the importance of emission control for biomass combustion systems in urban area, and the need to take above-ground pollutant “hotspots” into account when permitting distributed generation. The effects of ambient wind speed and stack temperature, the suitability of airport meteorological data on micro-environmental air quality were explored, and the implications on mitigating near-source air pollution were discussed.
显示更多 [+] 显示较少 [-]Water quantity and quality response of a green roof to storm events: Experimental and monitoring observations 全文
2016
Carpenter, Corey M.G. | Todorov, Dimitar | Driscoll, Charles T. | Montesdeoca, Mario
Syracuse, New York is working under a court-ordered agreement to limit combined sewer overflows (CSO) to local surface waters. Green infrastructure technologies, including green roofs, are being implemented as part of a CSO abatement strategy and to develop co-benefits of diminished stormwater runoff, including decreased loading of contaminants to the wastewater system and surface waters. The objective of this study was to examine the quantity and quality of discharge associated with precipitation events over an annual cycle from a green roof in Syracuse, NY and to compare measurements from this monitoring program with results from a roof irrigation experiment. Wet deposition, roof drainage, and water quality were measured for 87 storm events during an approximately 12 month period over 2011–2012. Water and nutrient (total phosphorus, total nitrogen, and dissolved organic carbon) mass balances were conducted on an event basis to evaluate retention annually and during the growing and non-growing seasons. These results are compared with a hydrological manipulation experiment, which comprised of artificially watering of the roof. Loadings of nutrients were calculated for experimental and actual storms using the concentration of nutrients and the flow data of water discharging the roof. The green roof was effective in retaining precipitation quantity from storm events (mean percent retention 96.8%, SD = 2.7%, n = 87), although the relative fraction of water retained decreased with increases in the size of the event. There was no difference in water retention of the green roof for the growing and non-growing seasons. Drainage waters exhibited high concentration of nutrients during the warm temperature growing season, particularly total nitrogen and dissolved organic carbon. Overall, nutrient losses were low because of the strong retention of water. However, there was marked variation in the retention of nutrients by season due to variations in concentrations in roof runoff.
显示更多 [+] 显示较少 [-]Organobromine compound profiling in human adipose: Assessment of sources of bromophenol 全文
2015
Gao, Shixiong | Wan, Yi | Zheng, Guomao | Luo, Kai | Kannan, Kurunthachalam | Giesy, John P. | Lam, Michael H.W. | Hu, Jianying
Bromophenols (BRPs) have been widely detected in human tissues, however, relative proportions from natural products and/or anthropogenic flame retardants are not clear. 21 polybrominated diphenyl ethers (PBDEs), 15 MeO/OH-PBDEs, and 10 BRPs were simultaneously quantified in adipose collected from people from New York City, USA. An in vitro assay utilizing human liver microsomes was performed for detected predominant organobromine. High concentrations of 2,4,6-triBRP and PBDEs were observed, and extremely low concentrations of naturally occurring MeO/OH-PBDEs were detected. Similar biotransformatioin rates of BRPs and MeO/OH-PBDEs indicated that the relative high concentration of 2,4,6-triBRP in humans was not of natural origin. Significant correlation observed between concentrations of 2,4,6-triBRP and BDE-209 suggested that the two chemicals may share a common source. Both 2,4,6-triBRP and BDE-209 were detected in commercial ABS resins, suggesting that plastic products made from ABS resins could be potential sources of co-exposure of the two compounds for humans.
显示更多 [+] 显示较少 [-]Modeled PM2.5 removal by trees in ten U.S. cities and associated health effects 全文
2013
Nowak, David J. | Hirabayashi, Satoshi | Bodine, Allison | Hoehn, Robert
Urban particulate air pollution is a serious health issue. Trees within cities can remove fine particles from the atmosphere and consequently improve air quality and human health. Tree effects on PM2.5 concentrations and human health are modeled for 10 U.S. cities. The total amount of PM2.5 removed annually by trees varied from 4.7 tonnes in Syracuse to 64.5 tonnes in Atlanta, with annual values varying from $1.1 million in Syracuse to $60.1 million in New York City. Most of these values were from the effects of reducing human mortality. Mortality reductions were typically around 1 person yr−1 per city, but were as high as 7.6 people yr−1 in New York City. Average annual percent air quality improvement ranged between 0.05% in San Francisco and 0.24% in Atlanta. Understanding the impact of urban trees on air quality can lead to improved urban forest management strategies to sustain human health in cities.
显示更多 [+] 显示较少 [-]Impact of local traffic exclusion on near-road air quality: Findings from the New York City “Summer Streets” campaign 全文
2011
Whitlow, Thomas H. | Hall, Andrew | Zhang, K Max | Anguita, Juan
We monitored curbside airborne particulate matter (PM) concentrations and its proinflammatory capacity during 3 weekends when vehicle traffic was excluded from Park. Ave., New York City. Fine PM concentration peaked in the morning regardless of traffic while ultrafine PM was 58% lower during mornings without traffic. Ultrafine PM concentration varied linearly with traffic flow, while fine PM spiked sharply in response to random traffic events that were weakly correlated with the traffic signal cycle. Ultrafine PM concentrations decayed exponentially with distance from a cross street with unrestricted traffic flow, reaching background levels within 100 m of the source. IL-6 induction was typically highest on Friday afternoons but showed no clear relationship to the presence of traffic. The coarse fraction (>2.5 μm) had the greatest intrinsic inflammatory capacity, suggesting that coarse PM still warrants attention even as the research focus is shifting to nano-particles.
显示更多 [+] 显示较少 [-]Road deicing salt irreversibly disrupts osmoregulation of salamander egg clutches 全文
2011
Karraker, Nancy E. | Gibbs, James P.
It has been postulated that road deicing salts are sufficiently diluted by spring rains to ameliorate any physiological impacts to amphibians breeding in wetlands near roads. We tested this conjecture by exposing clutches of the spotted salamander (Ambystoma maculatum) to three chloride concentrations (1 mg/L, 145 mg/L, 945 mg/L) for nine days, then transferred clutches to control water for nine days, and measured change in mass at three-day intervals. We measured mass change because water uptake by clutches reduces risks to embryos associated with freezing, predation, and disease. Clutches in controls sequestered water asymptotically. Those in the moderate concentrations lost 18% mass initially and regained 14% after transfer to control water. Clutches in high concentration lost 33% mass and then lost an additional 8% after transfer. Our results suggest that spring rains do not ameliorate the effects of deicing salts in wetlands with extremely high chloride concentrations.
显示更多 [+] 显示较少 [-]Gaseous mercury emissions from unsterilized and sterilized soils: The effect of temperature and UV radiation 全文
2009
Choi, Hyun-Deok | Holsen, Thomas M.
Mercury (Hg) emissions from the soils taken from two different sites (deciduous and coniferous forests) in the Adirondacks were measured in outdoor and laboratory experiments. Some of the soil samples were irradiated to eliminate biological activity. The result from the outdoor measurements with different soils suggests the Hg emission from the soils is partly limited by fallen leaves covering the soils which helps maintain relatively high soil moisture and limits the amount of heat and solar radiation reaching the soil surface. In laboratory experiments exposure to UV-A (365 nm) had no significant effect on the Hg emissions while the Hg emissions increased dramatically during exposure to UV-B (302 nm) light suggesting UV-B directly reduced soil-associated Hg. Overall these results indicate that for these soils biotic processes have a relatively constant and smaller influence on the Hg emission from the soil than the more variable abiotic processes. Hg emission measurements from soils indicate that abiotic processes were more important than biotic processes in reducing Hg and controlling emissions.
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