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Environmental Toxicology and Chemistry

Nicholas Maya, Jaden Evans, Deniz Nasuhoglu, Siavash Isazadeh, Viviane Yargeau, Chris D Metcalfe
While conventional wastewater treatment technologies are effective at removing many contaminants of emerging concern (CECs) from municipal wastewater, some contaminants are not removed efficiently. Ozonation may be a treatment option for reducing the concentrations of recalcitrant CECs in wastewater, but this process may generate toxic transformation-products. In the present study, we conducted semi-batch experiments to ozonate municipal wastewater effluent (WWE) spiked with 5 commonly detected CECs. The purpose of the study was to evaluate whether ozonation increased or decreased biological responses indicative of sublethal toxicity in juvenile rainbow trout (Oncorhynchus mykiss) injected intraperitoneally (i...
August 16, 2017: Environmental Toxicology and Chemistry
Luísa Becker Bertotto, Jaben Richards, Jay Gan, David Christopher Volz, Daniel Schlenk
Bifenthrin (BF) is a pyrethroid insecticide used in urban and agricultural applications. Previous studies have shown that environmentally relevant (ng/L) concentrations of BF increased plasma concentrations of 17β-estradiol (E2) and altered the expression of dopaminergic (DA) pathway components. DA neurons can indirectly regulate E2 biosynthesis, suggesting that BF may disrupt the hypothalamic-pituitary-gonadal (HPG) axis. Since embryos do not have a complete HPG axis, the hypothesis that BF impairs DA regulation was tested in embryonic and one-month old juvenile zebrafish (Danio rerio) with exposure to measured concentrations of 0...
August 16, 2017: Environmental Toxicology and Chemistry
Nicole K Mcrae, Chris N Glover, S Rebekah Burket, Bryan W Brooks, Sally Gaw
Diclofenac is a non-steroidal anti-inflammatory drug of growing concern in aquatic environments worldwide, yet knowledge of its effects on aquatic biota are restricted to a few model species and mechanisms of impact. In the current study, diclofenac accumulation, its effects on metabolic rate, ionoregulation, and oxidative stress were examined at environmentally-relevant (0.17 μg L-1) and elevated (763 μg L-1) concentrations in a culturally and economically important galaxiid fish, inanga (Galaxias maculatus), from the Southern Hemisphere...
August 12, 2017: Environmental Toxicology and Chemistry
Paul L Mosquin, Jeremy Aldworth, Wenlin Chen
Potential "peak" functions (e.g., maximum rolling averages over a given duration) of annual pesticide concentrations in the aquatic environment are important exposure parameters (or target quantities) for ecological risk assessments. These target quantities require accurate concentration estimates on non-sampled days in a monitoring program. In this paper, we examine stream flow as a covariate via universal kriging to improve predictions of maximum m-day (m = 1, 7, 14, 30, 60) rolling averages and the 95(th) percentiles of atrazine concentration in streams where data were collected every 7 or 14 days...
August 12, 2017: Environmental Toxicology and Chemistry
Nailiang Sun, Hongyuan Wang, Zongqi Ju, Hongfeng Zhao
The study examined the effects of chronic cadmium exposure on metamorphosis, body size, thyroid gland, and skeletal development of Chinese toad (Bufo gargarizans) tadpoles. Tadpoles were exposed to cadmium concentrations at 0, 5, 10, 50,100 and 500 μg/L from Gonser stage 26 to Gosner stage 46 of completion of metamorphosis. Our results showed 100 and 500 μg/L cadmium concentrations increased mortality and decelerated metamorphosis rate. In addition, significant body size reduction at Gosner stage 42 was observed at 100 and 500 μg/L cadmium treatments (p < 0...
August 11, 2017: Environmental Toxicology and Chemistry
Jing Liu, Birendra Dhungana, George P Cobb
Copper oxide nanoparticles (nCuO) are widely used in many industries. The increasing release of nCuO from both intentional and unintentional sources into the environment may pose risks to rice plants, thereby reducing the quality or quantity of this staple grain in the human diet. Arsenic (As) contamination has not only decreased rice yield, As accumulation in rice has also been a great human health concern for a few decades. New technologies have succeeded in removing As from water by nanomaterials. By all accounts, few studies address nCuO phytotoxicity to rice, and the interactions of nCuO with As are poorly described...
August 10, 2017: Environmental Toxicology and Chemistry
Vera L Maria, Maria João Ribeiro, Sofia Guilherme, Amadeu M V M Soares, Janeck J Scott-Fordsmand, Mónica J B Amorim
Enchytraeids have been used in standard ecotoxicity testing for about 20 years now. Since adopting the standard test for survival and reproduction, a number of additional tools have been developed, including transcriptomics and enzymatic biomarkers. So far, a genotoxicity tool and endpoint have not been used; hence, the goals of the current study included the optimization of the in vivo alkaline comet assay in Enchytraeus crypticus. Further, the effect of silver nanomaterial (Ag NM300K, dispersed, 15 nm) was tested and compared with AgNO3 ...
August 10, 2017: Environmental Toxicology and Chemistry
Elvira Mennillo, Augustine Arukwe, Gianfranca Monni, Valentina Meucci, Luigi Intorre, Carlo Pretti
The increased use of non-steroidal anti-inflammatory drugs (NSAIDs) has resulted in their ubiquitous presence in the environment. The toxicological properties of these two widely prescribed NSAIDs, namely - racemic ketoprofen (rac-KP) and its enantiomer S(+)-ketoprofen (dexketoprofen, DKP) were evaluated. Firstly, by acute and chronic toxicity tests using three representative model organisms (Vibrio fischeri, Pseudokirchneriella subcapitata and Ceriodaphnia dubia). Secondly, by evaluating the responses of biotransformation systems and multidrug resistance associated proteins (MRP1/MRP2) using the PLHC-1 fish hepatic cell-line...
August 10, 2017: Environmental Toxicology and Chemistry
Marc Fraser, Marlène Fortier, Delphine Foucher, Pierre-Hervé Roumier, Pauline Brousseau, Michel Fournier, Céline Surette, Cathy Vaillancourt
Serotonin plays a crucial role in mussel survival and reproduction. Although serotonin system can be affected by metals, the effects of environmental concentration of metals, such as manganese (Mn), lead (Pd), and cadmium (Cd), have never been studied in blue mussels. This study aims to determine the effects of exposure to Mn, Pb or Cd on serotonin levels, monoamine oxidase (MAO) activity, and serotonin transporter (SERT) in the blue mussel, Mytilus edulis. Mussels were exposed in vivo to increasing and environmentally relevant doses of Mn (10-1000 nM; 0...
August 10, 2017: Environmental Toxicology and Chemistry
Nicholas Maya, Calvin Crispo, Victoria McFarland, Deniz Nasuhoglu, Siavash Isazadeh, Viviane Yargeau, Chris D Metcalfe
Treatment of municipal wastewater reduces the concentrations of some pharmaceuticals and personal care products, hormones and drugs of abuse. However, reduced concentrations of these micropollutants in wastewater may not correlate with reduced toxicity, as transformations of micropollutants and/or the formation of disinfection by-products may generate toxic compounds. In this study, we prepared extracts by solid phase extraction of samples collected from wastewater treatment plants (WWTPs) at various stages of treatment and tested these extracts for toxicity to early life stages of Japanese medaka (Oryzias latipes)...
August 9, 2017: Environmental Toxicology and Chemistry
Martin Tsz-Ki Tsui, Evan M Adams, Allyson K Jackson, David C Evers, Joel D Blum, Steven J Balogh
Mercury (Hg) stable isotope analysis is an emerging technique that has contributed to a better understanding of many aspects of the biogeochemical cycling of Hg in the environment. However, no study has yet evaluated its usefulness in elucidating the sources of methylmercury (MeHg) to songbird species, a common organism for biomonitoring of Hg in forested ecosystems. In this pilot study, we examined stable mercury isotope ratios in blood of four species of songbirds and the invertebrates they are likely foraging upon in multiple habitats in a small watershed of mixed forest and wetlands in Acadia National Park in Maine, U...
August 9, 2017: Environmental Toxicology and Chemistry
Jennifer M Korstian, Matthew M Chumchal, Victoria J Bennett, Amanda M Hale
Mercury (Hg) is a highly toxic metal that has detrimental effects on wildlife. We surveyed Hg concentrations in 10 species of bats collected at wind farms in the central United States and found contamination in all species. Mercury concentration in fur was highly variable both within and between species (range 1.08-10.52 μg/g). Despite the distance between sites (up to 1200 km), only 2 of the 5 species sampled at multiple locations had fur Hg concentrations that differed between sites. Mercury concentrations observed in the present study all fell within the previously reported ranges for bats collected from the northeastern United States and Canada, although many of the bats we sampled had lower maximum Hg concentrations...
August 9, 2017: Environmental Toxicology and Chemistry
Elin M Ulrich, Patti L Tenbrook, Larry M Mcmillan, Qianheng Wang, Wenjian Lao
Some current-use pesticides are chiral and have non-superimposable mirror images called enantiomers that exhibit identical physical-chemical properties but can behave differently when in contact with other chiral molecules (e.g., regarding degradation and uptake). These differences can result in variations in enantiomer presence in the environment and potentially change the toxicity of pesticide residues. Several current-use chiral pesticides are applied in urban and agricultural areas, with increased potential to enter watersheds and adversely affect aquaticorganisms...
August 8, 2017: Environmental Toxicology and Chemistry
Sofie Moyson, Kris Vissenberg, Erik Fransen, Ronny Blust, Steven J Husson
In this study toxicity effects of zinc, copper and cadmium, both as single metals and in combination, were examined for the nematode Caenorhabditis elegans. Metal effects on lethality were analysed in a time-dependent manner using different concentrations in K-medium. LC20 concentrations were used to investigate the effects on locomotion and chemosensation. The results showed that copper toxicity was higher compared to cadmium and zinc, resulting in higher mortality rates and a more reduced locomotion. For all metals lethality increased over time...
August 8, 2017: Environmental Toxicology and Chemistry
René P A Van Wijngaarden, Gertie H P Arts
In the aquatic Tier-1 effect assessment for plant protection products with a herbicidal mode of action in Europe, it is usually algae and/or vascular plants that determine the environmental risks. This tier includes tests with at least two algae and one macrophyte (Lemna). Although considered of a chronic nature based on the duration of the test in relation to the life cycle of the organism, the measurement endpoints that are derived from the laboratory tests with plants (including algae) and used in the first tier effect assessment for herbicides are acute effect concentrations affecting 50% of the test organisms (EC50 values) and not NOEC or EC10 values...
August 8, 2017: Environmental Toxicology and Chemistry
Keenan Munno, Paul A Helm, Donald A Jackson, Chelsea Rochman, Alina Sims
Alkaline and wet peroxide oxidation (WPO) chemical digestion techniques used to extract microplastics from organic matrices were assessed for recoveries and for impacts on ability to identify polymer types. Methods using WPO generated enough heat to result in the complete loss of some types of microplastic particles, and boiling tests confirmed that temperatures >70 °C were responsible for the losses. Fourier transform infrared spectroscopy (FTIR) confirmed minimal alteration of the recovered polymers by the applied methods...
August 7, 2017: Environmental Toxicology and Chemistry
Perrine Dranguet, Séverine Le Faucheur, Vera I Slaveykova
Mercury (Hg) compounds represent an important risk to aquatic ecosystems due to their persistence, bioaccumulation and biomagnification potential. In the present review, we critically examine the state-of-the-art studies concerning the interactions of Hg compounds with freshwater biofilms with emphasis on Hg accumulation, transformations and effects. Freshwater biofilms contain both primary producers (e.g. algae) and decomposers (e.g bacteria and fungi), which contribute to both aquatic food webs and microbial loop...
August 3, 2017: Environmental Toxicology and Chemistry
Tiffany Carro, Mary K Walker, Karen M Dean, Mary Ann Ottinger
Tree swallow (Tachycineta bicolor) eggs from two uncontaminated sites, Patuxent Research Refuge (PRR), MD and Cobleskill Reservoir, NY were dosed with PCB 77 to evaluate effects on the developing cardiovascular system. To ensure embryonic viability, treatments were administered into the air cell at embryonic day (ED) 2.5 including: untreated (control), vehicle (filtered sterilized fatty acid mixture), 100 ng/g and 1,000 ng/g egg. Eggs were dosed in the field with 0.2 μl per egg, returned to the nest, collected at ED13, hatched in the laboratory and necropsied...
August 2, 2017: Environmental Toxicology and Chemistry
Hilda Fadaei, Ernest Williams, Allen Place, John Connolly, Upal Ghosh
Uptake of polychlorinated biphenyls (PCBs) by fish is controlled by the bioavailability of ingested PCBs in the gut and the freely dissolved concentration in the water moving across the gills. Prediction of bioaccumulation in fish relies on models that account for these exposure routes, however, these models typically do not account for incidental ingestion of sediment by fish, which is not well studied. The literature values for the PCB assimilation efficiency (AE) in the gut have been reported for compounds in food matrices and not associated with sediment particles...
August 1, 2017: Environmental Toxicology and Chemistry
Kyoshiro Hiki, Tomohiro Tobino, Fumiyuki Nakajima, Kenta Tsukahara
An acute sediment toxicity test using the ostracod Heterocypris incongruens is user friendly and has high sensitivity; however, a life-cycle test using this species has not been developed. The most challenging problem when developing a life-cycle test is that the egg development time varies greatly and is sometimes too long (>150 days) to monitor. It is desirable to shorten the duration of life-cycle toxicity tests including the observation period of egg development while preserving the ecological relevance of the net reproductive rate (R0), an endpoint in the life-cycle test...
July 29, 2017: Environmental Toxicology and Chemistry
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