Pennsylvania Department of Environmental Protection

Biogenic volatileorganic compounds (BVOCs) emitted fromaquaticsystems are increasingly recognized for their influence on atmosphericchemistry. However, emissions from freshwater environments, specificallyduring harmful algal bloom (HAB) events, remain poorly quantified.These HAB events are increasing globally in frequency and intensity,driven by climate change, nutrient runoff, and land-use changes. Thisstudy investigates the water-to-air gas exchange rates of BVOCs fromsouthwestern Pennsylvanian freshwater lakes during peak HAB conditions,with a focus on nitrogen-containing compounds that are typically underrepresentedin atmospheric measurements. Using atmospheric pressure, hydroniumchemical ionization mass spectrometry (CIMS), we measured BVOC emissionsfrom 18 lake samples in the laboratory, capturing real-time fluxesof 900 unique masses. Ammonia, pyrroline, and pyridine consistentlyexhibited the highest emission fluxes across samples. Alkylamineswere less abundant, although they remain atmospherically importantdue to their role in new particle formation. These results representthe first reported real-time freshwater flux measurements of alkylamines,pyrroline, and pyridine, offering new insight into the atmosphericimplications of HABs. Notably, no clear correlation was observed betweenBVOC fluxes and chlorophyll a and phycocyanin concentrations,which were taken to represent the cyanobacterial concentrations inthe samples. This suggests that emissions are influenced by otherbiological or chemical factors not captured in this study. Principalcomponent analysis identified two significant outlier water samples,driven by elevated ammonia, pyrroline, and an unknown compound at124.101 amu, though the underlying cause of these deviations remainsunresolved. The remaining lake emissions were similar. These findingsprovide foundational observations to better understand the role offreshwater system emissions in regional air quality and atmosphericprocesses.

Per- and polyfluoroalkyl substances (PFAS) have become an environmental issue worldwide. A first step to assessing potential adverse effects on fish populations is to determine if concentrations of concern are present in a region and if so, in which watersheds. Hence, plasma from adult smallmouth bass Micropterus dolomieu collected at 10 sites within 4 river systems in the mid-Atlantic region of the United States, from 2014 to 2019, was analyzed for 13 PFAS. These analyses were directed at better understanding the presence and associations with land use attributes in an important sportfish. Four substances, PFOS, PFDA, PFUnA, and PFDoA, were detected in every plasma sample, with PFOS having the highest concentrations. Sites with mean plasma concentrations of PFOS below 100 ng/ml had the lowest percentage of developed landcover in the upstream catchments. Sites with moderate plasma concentrations (mean PFOS concentrations between 220 and 240 ng/ml) had low (< 7.0) percentages of developed land use but high (> 30) percentages of agricultural land use. Sites with mean plasma concentrations of PFOS > 350 ng/ml had the highest percentage of developed land use and the highest number PFAS facilities that included military installations and airports. Four of the sites were part of a long-term monitoring project, and PFAS concentrations of samples collected in spring 2017, 2018, and 2019 were compared. Significant annual differences in plasma concentrations were noted that may relate to sources and climatic factors. Samples were also collected at two sites for tissue (plasma, whole blood, liver, gonad, muscle) distribution analyses with an expanded analyte list of 28 PFAS. Relative tissue distributions were not consistent even within one species of similar ages. Although the long-chained legacy PFAS were generally detected more frequently and at higher concentrations, emerging compounds such as 6:2 FTS and GEN X were detected in a variety of tissues.

HighlightsConcern over nutrient runoff from agriculture has prompted research to limit phosphorus (P) mobility.Mine drainage residuals (MDRs) can reduce phosphorus solubility in soils, sediments and liquid manure slurries.MDR amendment resulted in lower dissolved phosphorus in runoff from sites treated with dairy manure slurry, but not with swine manure slurry.This study underscores the value of testing under field conditions before making recommendations.Abstract. Concern over nutrient runoff from agriculture has prompted considerable research on amendments to limit phosphorus (P) solubility of manure slurries and P mobility following land application of the slurry. The concept of solving one industry’s problem with another industry’s problem is attractive, but successful examples are uncommon. Mine drainage residual (MDR), generated from the process of neutralizing acid discharge from coal mines, has been shown to reduce soluble P in soils, sediments and manure slurries. We therefore sought to test whether amending manure slurries with MDR was effective at reducing P in runoff once that slurry was applied to agricultural soils. A series of simulated rainfall experiments revealed that amending dairy manure slurry with MDR resulted in significantly less flow weighted dissolved P concentrations and loads in runoff. However, the same effect was not observed with runoff from soils amended with swine manure slurry, despite a greater reduction of water extractable P in swine manure slurry with MDR addition than in dairy manure slurry. This study underscores the value of testing amendments under field conditions before making manure management recommendations. Keywords: Manure, Phosphorus, Mine drainage residual, Engineered treatment, Simulated rainfall.

Since the recent introduction of the Asian longhorned tick (Haemaphysalis longicornis Neumann) in the United States, quantitative surveillance information remains lacking, which hinders accurate estimates of population structure and entomological risk. We conducted statewide, active tick surveillance from May to August 2019 and report data on H. longicornis geographical distribution and population density in Pennsylvania. In total, 615 H. longicornis were collected from four counties. Across samples recovering H. longicornis, mean density of H. longicornis was 9.2/100 m2, comparably greater than Ixodes scapularis Say (8.5/100 m2). Density of H. longicornis was also significantly greater in August, largely driven by larvae, and greater in recreational habitat types (12.6/100 m2) and in Bucks County (11.7/100 m2), situated adjacent to the location of the first U.S. discovery of intense infestations. These data are among the first to document H. longicornis from statewide tick surveillance and provide initial measures of population density enabling more quantitative characterizations of distributional patterns.

“Academic freedom does not exist for its own sake. Its foundational purpose is to create an environment of openness to advance inquiry in the interest of seeking truth, to support, facilitate, and enable the best minds of our time, and to train the next generation of young researchers to fulfill their roles in society …” Read more in the Guest Editorial by Joseph S. Francisco et al.

Abstract Benthic macroinvertebrates are used commonly as water-quality indicators in wadeable streams and rivers. However, increased depth and overall complexity of large rivers may cause inaccessibility or unacceptable index and metric variability when attempting a single wadeable method. Significant increases in sampling effort and time expenditure have been recommended to compensate for the increased variability when assessing large rivers. However, the transition between wadeable streams and nonwadeable rivers is not well defined, especially for free-flowing systems. We evaluated the utility of a modified wadeable-stream collection method for sampling large and complex semiwadeable rivers. Our results suggest that water-quality measurements across the width of a river can be used to identify influences of multiple water sources. This spatial information and a single-habitat (e.g., riffle–run) approach could be used with a modest increase in sampling effort to reduce metric variability and provide impor...

Analysis of dissolved light hydrocarbon gas concentrations (primarily methane and ethane) in water supply wells is commonly used to establish conditions before and after drilling in areas of shale gas and oil extraction. Several methods are currently used to collect samples for dissolved gas analysis from water supply wells; however, the reliability of results obtained from these methods has not been quantified. This study compares dissolved methane and ethane concentrations measured in groundwater samples collected using three sampling methods employed in pre- and post-drill sampling programs in the Appalachian Basin. These include an open-system collection method where 40 mL volatile organic analysis (VOA) vials are filled directly while in contact with the atmosphere (Direct-Fill VOA) and two alternative methods: (1) a semi-closed system method whereby 40 mL VOA vials are filled while inverted under a head of water (Inverted VOA) and (2) a relatively new (2013) closed system method in which the sample is collected without direct contact with purge water or the atmosphere (IsoFlask® ). This study reveals that, in the absence of effervescence, the difference in methane concentrations between the three sampling methods was relatively small. However, when methane concentrations equaled or exceeded 20 mg/L (the approximate concentration at which effervescence occurs in the study area), IsoFlask® (closed system) samples yielded significantly higher methane concentrations than Direct-Fill VOA (open system) samples, and Inverted VOA (semi-closed system) samples yielded lower concentrations. These results suggest that open and semi-closed system sample collection methods are adequate for non-effervescing samples. However, the use of a closed system collection method provides the most accurate means for the measurement of dissolved hydrocarbon gases under all conditions.

The aim of this study was to investigate the effects of a specific diet, containing beta-hydroxy-beta-methylbutyrate, L-glutamine and L-arginine (HMB/Glu/Arg), on chemoradiation-induced injuries of the rat gastrointestinal mucosa. Wistar albino rats were divided into 4 groups: control (n = 5); radiation (n = 14); 5-fluorouracil treatment (5-FU; n = 14); and radiation and 5-FU treatment (n = 14). Rats were fed either a standard diet or a specific diet (SpD) containing HMB/Glu/Arg supplementation for 7 days prior to radiation exposure and/or 5-FU treatment. The irradiated groups were exposed to an 1 Gy dose of 6 MV x rays delivered to the who-abdominal. The animals receiving 5-FU treatment were given a 100 mg/kg dose of the drug. In the radiation and 5-FU treatment group, the 5-FU was administered 30 min prior to irradiation. After irradiation and/or 5-FU treatment, feeding with either the standard rat diet or specific diet continued as before. All animals were sacrificed on day 4 after irradiation and 5-FU treatment. Data collected included microbiological, histological and immunohistochemical end points. We found that bacterial colony counts in the ceca and mesenteric lymph nodes of irradiated rats treated with 5-FU were significantly lower in the specific diet (SpD) group than in the standard diet group (P = 0.002-0.05). Morphometrically, gastric, duodenal and colonic mucosal injuries were less severe in the irradiated animals fed the specific diet, as well as the 5-FU-treated animals fed the specific diet, compared to the similarly treated standard diet groups. Apoptosis, measured by TUNEL, revealed significantly lower numbers of TUNEL positive cells in irradiated animals fed the specific diet, and irradiated animals treated with 5-FU and fed the specific diet compared to irradiated animals fed the standard diet, and irradiated animals treated with 5-FU and fed the standard diet. In the 5-Fu-treated and SpD group, the extent of apoptosis was significantly lower than that of the 5-Fu-treated and standard diet group in both the stomach and duodenum (P = 0.0001), but not in the colon. Apoptosis, measured by caspase 3 staining, was significantly less in all three organs of the SpD groups. In conclusion, these findings suggest that a diet supplemented with HMB/Glu/Arg may ameliorate the effect of radiation-induced gastrointestinal injury, coinciding with reduced bacterial growth.

Although Pennsylvania has recently reported the greatest number of Lyme disease cases in the United States, with the largest increase for PA occurring in its western region, the population biology of the blacklegged tick (Ixodes scapularis Say) has not been adequately characterized in western PA. We studied the seasonal activity of host-seeking I. scapularis larvae, nymphs, and adults in mid-western PA over the course of a year, including a severe winter, and determined their absolute densities and collection efficiencies using replicated mark-release-recapture or removal methods. Our results are compared to those from similar studies conducted in the highly Lyme disease endemic Hudson Valley region of southeastern New York State. The seasonal activity of I. scapularis was intermediate between patterns observed in the coastal northeastern and upper Midwestern United States. Only one peak of larval activity was observed, which was later than the major peak in the Midwest, but earlier than in the northeast. Seasonal synchrony of larvae and nymphs was similar to the northeast, but the activity peaks were much closer together, although not completely overlapping as in the Midwest. Pre- and postwinter relative densities of questing adult I. scapularis were not significantly different from one another. The absolute densities and collection efficiencies of larvae, nymphs, and adults were comparable to results from classic research conducted at the Louis Calder Center in Westchester County, NY. We conclude that the population biology of I. scapularis in mid-western PA is similar to southeastern NYS contributing to a high acarological Lyme disease risk.

The first confirmed collection of Aedes stimulans in Louisiana was made in St. Tammany Parish, LA. A single adult female was collected by a large-bore aspirator in March 2011, and identified by microscopic and molecular methods. Notes are provided on the morphology, location, habitat, and potential mosquito associates that may be found with Ae. stimulans.