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Fish are acutely affected by the increasing number of chemicals in the ambient water, including endocrine disruptors (EDC’s). EDCs include heavy metals such as cadmium and mercury, the polycyclic hydrocarbon benzo(a)pyrene, polychlorinated biphenyls, phthalates, carbamate and organophosphate pesticides, organochlorines, and bisphenol A. Nevertheless, certain groups of EDCs do manifest a comparatively greater effect on specific endocrine glands. The endocrine dysfunctions induced by explicitly acting EDCs include changes in fertility and in the ratio of male and female fish, classified as xenoestrogens or xenoandrogens. These EDCs result in a high prevalence of intersex condition including sex reversal. Feminization of male and masculinization of female fish pose a serious threat for fish populations, causing reduction or even breakdown of the reproductive performance of fish and of the yield of fisheries. It is now widely accepted that fish provide reliable biomarkers of early effects of EDC’s which data can be used as a warning signal for the ecosystem in general and a lever to diminish or prevent further release of effluents and discharges from anthropogenic activities.

The physiology and behaviour of fish are strongly affected by ambient water temperature. Physiological traits related to metabolism, such as aerobic scope (AS), can be measured across temperature gradients, and the resulting performance curve reflects the thermal niche that fish can occupy. We measured AS of westslope cutthroat trout (Oncorhynchus clarkii lewisi) at 5, 10, 15, 20, and 22 °C and compared temperature preference (T pref) of the species with non-native brook trout (Salvelinus fontinalis), brown trout (Salmo trutta), and rainbow trout (Oncorhynchus mykiss). Intermittent-flow respirometry experiments demonstrated that metabolic performance of westslope cutthroat trout was optimal at ∼15 °C and decreased substantially beyond this temperature, until lethal temperatures at ∼25 °C. Adjusted T pref across species were comparatively high, ranging from 17.8 to 19.9 °C, with the highest T pref observed for westslope cutthroat trout. Results suggest that although westslope cutthroat trout is considered a cold-water species, they do not prefer or perform as well in cold water (≤10 °C) and thus can occupy a warmer thermal niche than previously thought. The metabolic performance curve (AS) can be used to develop species‐specific thermal criteria to delineate important thermal habitats and guide conservation and recovery actions for westslope cutthroat trout.

Aims: Soaking followed by cooking is the main aspect of chickpea processing which reduces the time consumption in the cooking process for achieving the desired cooking texture and nutritional qualities. But soaking chickpea in ambient water is very time-consuming. Therefore, the present investigation was carried out to study the soaking characteristics of chickpea in different soaking conditions. Place and Duration of Study: Department of Agricultural Engineering, Centurion University of Technology & Management, between January 2021 to June 2021. Methodology: The chickpea was soaked in ambient water, hot water, and microwave heating applications. Results: The initial moisture content of the chickpea was found to be 14.39 % wet basis throughout the experiments. The moisture gain experimental was calculated and was found to be 45.21 % dry basis (db) in ambient water soaking. In the hot water soaking, the moisture gain was estimated to be 50.74 % db, 53.28 % db, and 65.18 % db at 40°C, 50°C, and 60°C, respectively after 360 min (6h) of soaking period. The moisture gains in microwave-assisted soaking at 0.2 W/g, 0.4 W/g, 0.6 W/g, 0.8 W/g, and 1.0 W/g power densities levels were found to be 44.78 % db, 64.44 % db, 81.42 % db, 106.36 % db, and 115.95 % db, respectively after 10 min. The Peleg model was found to be suitable for describing the soaking characteristics of chickpea at all soaking conditions with higher R2 values. The Peleg capacity constant and rate constant didn’t show any particular trend in all the soaking methods. Conclusion: Among all the soaking methods, microwave-assisted soaking showed the best soaking characteristics of chickpea with less time consumption and with more amount of moisture gain. Therefore, microwave-assisted may be recommended for soaking chickpea which is a less time-consuming and energy-saving process.

Severe ambient water pollution is common in many developing countries. A broad array of regulatory and other policy instruments can be used to improve water quality. However, some approache...

This study outfitted wild-caught white seabass (Atractoscion nobilis) with electronic data storage tags (DSTs) to evaluate subsequent movements of adult fish captured along Baja California, Mexico (BC). Cefas G5 DSTs were surgically implanted into 89 wild-caught white seabass ranging in size from 66 to 152 cm TL between La Salina (32.11°N/116.90°W) and San Quintin (30.25°N/115.83°W), BC. Twenty-four tagged individuals (27%) were recaptured between April, 2010 and May, 2017, following a mean time at liberty of 608 days (range = 18–1424 days) and a mean displacement of approximately 125 km (± 173 km; range = 3–720 km) between the point of release and recapture. Tagged white seabass were recaptured between Santa Rosalillita, BC (28.66° N/114.27°W) and Monterey Bay, California (36.65°N/121.86°W), with four individuals reported above the U.S-Mexico border. Collectively, 8547 days of archived data revealed that white seabass spent 95% of the time at depths

Ploidy manipulation, such as triploidy, in farmed oysters has been used as a tool to enhance oyster quality throughout all seasons because triploid oysters allocate less energy to gametogenesis, and therefore are deemed better performers than fertile diploids. Nevertheless, scientific reports describing no differences between ploidies and, in certain conditions, disadvantages of triploids are not uncommon. As the use of triploid oyster seed increases culture cost for growers, consistency in performance of triploids is considered to be an important goal. Thus, research to assess how ploidy affects physiological processes underlying oyster performance is fundamental for the aquaculture industry. This work was undertaken to assess if ploidy-based differences in performance in the two most commonly cultivated commercial species of oyster in the United States, Crassostrea virginica and Crassostrea gigas, are associated with filtration, feeding, and metabolism. To test this hypothesis, biodeposition measurements were made with oysters exposed to ambient water conditions at locations and seasons providing a variety of environmental conditions. Oysters did not show differences in filtration and feeding associated with ploidy, but physiological feeding variables fluctuated with environmental characteristics associated with spatial and seasonal differences. A preliminarily test of the hypothesis that differences in energy metabolism may account for differences in performance among ploidy levels indicates that basal metabolic rates of diploid, triploid, and tetraploid Eastern oysters are not different.

In the intial two decades of the twenty-first century, antibiotic (AB) resistance in human pathogens has emerged as a major challenge for water, sanitation, and public health. Considering these challenges, we critically reviewed AB-related studies with particular emphasis on their (i) patterns of consumption, (ii) pathway prevalences and environmental implications in ambient waters, and (iii) benefits and limitations of existing AB removal/purging techniques. We found that lifestyle, land use, urbanization, the ease of availability, and the tendency of the medical practitioners to recommend ABs are the key factors governing the AB use pathway and enrichment in the environment. In the developing world, the most prevalent group of ABs is quinolone, whereas in the developed world, older-generation AB groups are most prevalent. Further, enormous variability in the consumption of ABs around the globe is explicitly highlighted in this study. Ciprofloxacin has been reported in the highest concentration among all the ABs with 28–31 mg L−1 in the raw wastewater of the Indian subcontinent. We found that adsorption may be one of the most efficient AB removal techniques, and NaOH-activated carbon prepared from Macadamia nut shells is the most effective adsorbent identified to date. The literature showed that the Langmuir isotherm and pseudo-second-order kinetic model explain the AB adsorption mechanism most effectively. The future challenge lies in developing advanced protocols and markers to prioritize the strategy and simulate the ecotoxicities of the individual and a mixture of ABs.

Human-dominated waterways contain thousands of chemicals. Determining which chemical is the most important stressor is important, yet very challenging. The Toxicity Identification Evaluation (TIE) procedure from the US Environmental Protection Agency uses a series of chemical and physical manipulations to fractionate compounds within a matrix and systematically identify potential toxicants through laboratory bioassay testing. Although this may provide useful information, it lacks ecological realism because it is subject to laboratory-related artifacts and is resource intensive. The in situ Toxicity Identification Evaluation (iTIE) technology was developed to improve this approach and has undergone a number of modifications over the past several years. The novel prototype 3 consists of an array of iTIE ambient water fractionation units. Each unit is connected to a peristaltic pumping system with an organism exposure chamber that receives water from a resin chamber to chemically fractionate test site water. Test organisms included freshwater and marine standard toxicity test species. Postfractionation waters are collected for subsequent chemical analyses. Currently, the resins allow for separation of ammonia, metals, and nonpolar organics; the subsequent toxicity responses are compared between treatments and unfractionated, ambient exposures. The iTIE system was deployed to a depth of 3 m and evaluated in streams and marine harbors. Chemical analyses of water and iTIE chemical sorptive resins confirmed chemical groups causing lethal to sublethal responses. The system proved to be as sensitive or more so than the traditional phase 1 TIE test and required almost half of the resources to complete. This iTIE prototype provides a robust technology that improves stressor-causality linkages and thereby supports strong evidence for ecological risk weight-of-evidence assessments. Environ Toxicol Chem 2020;39:1746-1754. © 2020 SETAC.

The non-monotonic trends of thermodynamic response functions have long been a mystery of water. The idea, that water may be a mixture of two local states, came out more than a century ago to explain the origin of the non-monotonic behaviors. Recently, this idea is materialized through the hypothesis of the second critical point of water and then the anomalies are outcomes of critical fluctuation. Although the typical macroscopic heterogeneity (Widom line) of critical fluctuation stays in the vicinity of the critical point, as we have previously shown that the microscopic heterogeneity is identified far from it which extends the linear heterogeneity, the Widom line, to the areal one as a Widom Delta. With this background, we search for two local states of the ambient water. Distinct states in ambient condition are not to be contrasted by a single strong feature such as density but they are expressed by a combination of weak features that reflects locally correlated structures. In this work, we identify the formation of local bicontinuous micro-domain formations of water attributing its softness by using machine learning order parameters. Interestingly, the radial distribution functions are similar to two phases in the liquid-liquid phase transition and they are well fitted by the two-state model. The hard-label domain is dominant at a lower temperature but changes its label to a more fluctuating soft-label domain at high temperature. There exist crossover behaviors around 310–320 K. At sufficiently high temperatures, near the liquid-gas phase transition, all water molecules become homogeneous.

Gradual transfer experiments were conducted to see whether Japanese dace Tribolodon hakonensis (freshwater species) and Japanese black porgy Acanthopagrus schlegelii (marine species) could acclimate to high and low temperatures in natal and non-natal osmotic environments. Two groups of each species, one acclimated to their natal osmotic environment and the other to a non-natal osmotic environment, were exposed to gradual temperature changes. Under high temperature conditions, the plasma osmolality (Posm) of both species approached the osmolality of ambient water, and high mortality was observed in the non-natal osmotic environments but not in the natal osmotic environments. In contrast, there was no clear evidence that the osmoregulatory capacity of either species had declined under low temperature conditions in the natal and non-natal osmotic environments. Limited adaptation of these fishes to non-natal osmotic environments at high temperature suggests that global warming may impair their entry to non-natal habitats.

A description of historical and ambient water quality conditions is often required as part of navigational studies. This paper describes a series of tools developed by the USGS that can ai...

Heavy metals are widely concerning because of their toxicity, persistence, non-degradation and bioaccumulation ability. Human health ambient water quality criteria (AWQC) are specific levels of chemicals that can occur in water without harming human health. At present, most countries do not consider the effects of aquatic vegetables in deriving human health AWQC. Therefore, the intake of aquatic vegetables (Brasenia schreberi) was added to the derivation of human health AWQC and a health risk assessment for 13 heavy metals in Taihu Lake. The human health AWQC (consumption of water, fish and aquatic vegetables) values of 13 heavy metals ranged from 0.04 (Cd) to 710.87 µg/L (Sn), and the intake of B. schreberi had a very significant effect on the human health AWQC for Cu, with a more than 62-fold difference. The hazard quotients of As (2.8), Cd (1.6), Cr (1.4) and Cu (4.86) were higher than the safe level (HQ = 1), indicating that As, Cd, Cr and Cu in Taihu Lake posed a significant health risk. Sensitivity analysis showed that the contribution rate of B. schreberi intake to the human health risk from Cu was 91.6%, and all results indicated that the risk of Cu in B. schreberi to human health should be of particular concern. This study adds the consideration of aquatic vegetable consumption to the traditional method of human health AWQC derivation and risk assessments for the first time, and this approach can promote the development of risk assessments and water quality criteria.

Living crinoids are exclusively passive suspension feeders and benthic as adults. However, in the past they adapted to a broad range of ecological niches. For instance, the stratigraphically important middle Paleozoic scyphocrinoids are hypothesized to have been planktonic, employing their inferred gas-filled globular, chambered structure at the distal end of the stem, the so-called lobolith, as a buoyancy device with the crinoid calyx suspended below it. Here, we evaluate this hypothesis using evidence from skeletal micromorphology and theoretical biomechanical modeling. Lobolith walls are typically composed of ossicles, which are exclusively composed of constructional labyrinthic stereom. In plates from the distal side of the lobolith, this stereom extends into microperforate stereom layer, forming wavy ridges and spines. No microscale adaptations for preventing gas leaks and/or ingress of water (such as internal and external imperforate stereom layers) are known. Furthermore, theoretical calculations suggest that the scyphocrinoid tow-net mode of feeding would have resulted in small relative velocities between the towed filter and the ambient water, thus making it an ineffective passive filter feeder. We suggest that the lobolith of these crinoids acted as a modified holdfast rather than as a floating buoy. Its globular shape and distally positioned microspines served as adaptations for living in unconsolidated sediments, analogous to iceberg- and snowshoe-like strategies used by some mollusks and brachiopods. Like modern isocrinids, scyphocrinoids could have maintained an upright feeding posture by extending the distal portion of the stalk along the bottom. In this recumbent posture, the distal part of the stalk with the lobolith might have functioned as a drag anchor. As a consequence of the ~3-m-long stem, even with this posture, the benthic scyphocrinoids could have risen to the highest epifaunal tier in the Paleozoic.

Evolution of a solitary wave travelling along a submerged sill is studied. The disturbance from the sill creates a phase lag along the wave crest between the ambient water depth and the shallower depth over the sill. This phase lag causes wave diffraction between the different parts of the wave, which induces radiating waves off the edge of the sill. The radiating waves act as an outlet for wave energy, resulting in significant and continual amplitude reduction of the solitary wave. Findings from laboratory experiments are confirmed numerically by simulating a much longer propagation distance with different sill breadths. When the sill breadth is narrow, the solitary wave slowly attenuates by wave radiation, maintaining a quasi-steady wave pattern. This is not the case for a broader sill. The resulting phase lag on the sill continually changes the wave pattern and the attenuation rate is substantially greater than the rate for the case of the narrow sill. The significant energy radiation together with the continual change in the wave formation eventually leads to the complete annihilation of the solitary wave in a wave tank. We also report a wave-breaking process along the sill observed in laboratory experiments. This breaking is induced when the wave amplitude on the sill is smaller than the maximum amplitude of a solitary wave in a uniform depth. Also found is the wake-like formation of gravity–capillary waves behind the breaking crest forming on the sill. Other features associated with the breaking are presented.

Coliphage have been proposed as indicators of fecal contamination in recreational waters because they better reflect the persistence of pathogenic viruses in the environment and through wastewater treatment than traditional fecal indicator bacteria. Herein, we conducted a systematic literature search of peer-reviewed publications to identify coliphage density data (somatic and male-specific, or MSC) in raw wastewater and ambient waters. The literature review inclusion criteria included scope, study quality, and data availability. A non-parametric two-stage bootstrap analysis was used to estimate the coliphage distributions in raw wastewater and account for geographic region and season. Additionally, two statistical methodologies were explored for developing coliphage density distributions in ambient waters, to account for the nondetects in the datasets. In raw wastewater, the analysis resulted in seasonal density distributions of somatic coliphage (SC) (mean 6.5 log10 plaque forming units (PFU)/L; 95% confidence interval (CI): 6.2–6.8) and MSC (mean 5.9 log10 PFU/L; 95% CI: 5.5–6.1). In ambient waters, 49% of MSC samples were nondetects, compared with less than 5% for SC. Overall distributional estimates of ambient densities of coliphage were statistically higher for SC than for MSC (mean 3.4 and 1.0 log10 PFU/L, respectively). Distributions of coliphage in raw wastewater and ambient water will be useful for future microbial risk assessments.

Plastic is able to sorb environmental pollutants from ambient water and might act as a vector for these pollutants to marine organisms. The potential toxicological effects of plastic-sorbed pollutants in marine organisms have not been thoroughly assessed. In this study, organic extracts from four types of plastic deployed for 9 or 12 months in San Diego Bay, California, were examined for their potential to activate the aryl hydrocarbon receptor (AhR) pathway by use of the H4IIE-luc assay. Polycyclic aromatic hydrocarbons (PAH), including the 16 priority PAHs, were quantified. The AhR-mediated potency in the deployed plastic samples, calculated as bio-TEQ values, ranged from 2.7 pg/g in polyethylene terephthalate (PET) to 277 pg/g in low-density polyethylene (LDPE). Concentrations of the sum of 24 PAHs in the deployed samples ranged from 4.6 to 1068 ng/g. By use of relative potency factors (REP), a potency balance between the biological effect (bio-TEQs) and the targeted PAHs (chem-TEQs) was calculated to 24-170%. The study reports, for the first time, in vitro AhR-mediated potencies for different deployed plastics, of which LDPE elicited the greatest concentration of bio-TEQs followed by polypropylene (PP), PET, and polyvinylchloride (PVC).

Water temperature is doubtlessly one of the most important factors affecting the well-being of fish. For pikeperch Sander lucioperca an ambient water temperature of >20 °C has been suggested to achieve optimal growth in aquaculture farms, although natural habitats of pikeperch seldom reach such temperatures. We used multiplex qPCR arrays to assess the impact of temperature between 15 °C and 25 °C based on the expression of 38 potential biomarker genes characterising heat shock and hypoxia response, immune activation, energy supply and development in the liver and gills of pikeperch. In addition, liquid chromatography/mass spectrometry was used to assess the individual levels of glucocorticoids. Our data revealed that pikeperch do not develop severe responses to ambient temperatures between 15 °C and 25 °C, although specific parameters indicated a phased restriction of optimal conditions, above all the heat-shock genes SERPINH1, HSP90AA1 and HSPA8b; the acute-phase genes HP, C3 and SAA; and the transcription factor-encoding gene HMX1. In contrast to these in vivo observations, a temperature rise up to 37 °C led to an acute response in WF2-Sander cells characterised by the pronounced upregulation of HSP90AA1, HSP1A1, SERPINH1, HSPB1, HSPA8b and HSPB8. This report paves the ground for future assessment studies on the imbalanced homeostasis of pikeperch by means of molecular tools.

Fecal contamination of recreational waters with cattle manure can pose a risk to public health due to the potential presence of various zoonotic pathogens. Fecal indicator bacteria (FIB) have a long history of use in the assessment of recreational water quality, but FIB quantification provides no information about pollution sources. Microbial source tracking (MST) markers have been developed in response to a need to identify pollution sources, yet factors that influence their decay in ambient waters are often poorly understood. We investigated the influence of water type (freshwater versus marine) and select environmental parameters (indigenous microbiota, ambient sunlight) on the decay of FIB and MST markers originating from cattle manure. Experiments were conducted in situ using a submersible aquatic mesocosm containing dialysis bags filled with a mixture of cattle manure and ambient water. Culturable FIB (E. coli, enterococci) were enumerated by membrane filtration and general fecal indicator bacteria (GenBac3, Entero1a, EC23S857) and MST markers (Rum2Bac, CowM2, CowM3) were estimated by qPCR. Water type was the most significant factor influencing decay (three-way ANOVA, p: 0.006 to < 0.001), although the magnitude of the effect differed among microbial targets and over time. The presence of indigenous microbiota and exposure to sunlight were significantly correlated (three-way ANOVA, p: 0.044 to < 0.001) with decay of enterococci and CowM2, while E. coli, EC23S857, Rum2Bac, and CowM3 (three-way ANOVA, p: 0.044

MX precursor removal was compared at pilot-scale in continuously and cyclically operated biofilters with empty bed contact times (EBCTs) of 15 and 30 minutes. Water and filter media samples were collected under ambient water quality conditions and during a spike of 7 mg L−1 humic acid (HA). MX formation potential (FP) removals ranged from 26 to 49% and 45 to 61% under ambient precursor and spiked conditions, respectively, suggesting that biofiltration was capable of removing or altering MX precursors. Removal was very strongly correlated (R = 0.90) with ATP (a measure of biomass density) for all trials. MX FP reduction was significantly higher (p < 0.05) with respect to biomass density when comparing cyclically vs. continuously operated filters for all trials. Although lower average ATP concentrations were observed for the cyclically operated filters, these filters achieved a greater MX FP reduction per unit biomass which implies a higher rate of biological function. EBCT did not impact biofilter performance when considering MX FP reduction with respect to either filter depth or biomass density.

The ranges of the preferred and avoided temperatures in representatives of Thermocyclops crassus (Fischer, 1853) were determined by the results of experimental testing in a thermogradient aparatus and comparison of the obtained values with field observations of the optimal, pessimal and tolerated temperature conditions of development of these populations in nature. Copepods were sampled from pond located near Borok, Yaroslavl region, Russia (58o02'57'' N; 38o14'56'' E). The ambient water temperature was 15.0°С. Temperature preference was determined by the “chronic” method. The phenology of development of Th. crassus was observed in the field of water bodies in Central and Volga Federal Districts of Russia. The final thermal preferendum (FTP) achievement occurred with an increase in the preferred temperature: when animals were placed at a temperature in the thermal gradient (14.0–15.0°C) that approximated the temperature of the source pond, they moved to warmer water until they chose FTP (26.7°C). Obtained the values of FTP (25–30°C), temperature of normal performance (21–32°C) and pessimal temperatures of 9–20 and 33°С well coincide with numerous field observations for temperature conditions of development of species in northern waterbodies of Holarctic and with the temperatures at which populations of Th. crassus thrive in southern waterbodies of Holarctic and in tropical lakes. It is concluded that, despite the historically long existence of the species in the reservoirs of the temperate climatic zone, the northern populations of Th. crassus retained the temperature responses characteristic of their southern sister populations. And although the species has adapted to life in northern reservoirs at lower temperatures, when it becomes possible to choose, cyclops prefer temperatures above 25°C, which are optimal for southern populations living in tropical waters. These data once again confirm that the horizontal thermal gradient method can be used to infer temperature tolerance of freshwater cyclopoid copepods in nature.

Although the natural occurrence of arsenic-containing lipids (arsenolipids) in marine organisms is now well established, the possible role of these unusual compounds in organisms and in the cycling of arsenic in marine systems remains largely unexplored. We report the finding of arsenolipids in 61 plankton samples collected from surface marine waters of high- and low-nutrient content along a transect spanning the Gulf Stream in the North Atlantic Ocean. Using high-performance liquid chromatography (HPLC) coupled to both elemental and molecular mass spectrometry, we show that all 61 plankton samples contained six identifiable arsenolipids, namely, three arsenosugar phospholipids (AsPL958, 10-13%; AsPL978, 13-25%; and AsPL1006, 7-10% of total arsenolipids), two arsenic-containing hydrocarbons (AsHC332, 4-10% and AsHC360, 1-2%), and a methoxy-sugar arsenolipid that contained phytol (AsSugPhytol, 1-3%). The relative amounts of the six arsenolipids showed clear dependence on the nutrient status of the ambient water with plankton collected from high-nutrient waters having less of the arsenosugar phospholipids and more of the three non-P containing arsenolipids compared to low-nutrient waters. By combining these first field data of arsenolipids in plankton with reported global phytoplankton productivity, we estimate that the oceans' phytoplankton transform per year 50 000-100 000 tons of arsenic into arsenolipids.