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Environmental Toxicology and Chemistry

Gretchen L Lescord, Thomas A Johnston, Brian A Branfireun, John M Gunn
It is commonly assumed that the majority (>95%) of mercury (Hg) found in fish muscle is the toxic form, methylmercury (MeHg), due to its efficient assimilation and retention in biotic tissue. However, this assumption is based on studies examining the percent MeHg (%MeHg, the fraction of total Hg as MeHg) in muscle from mostly large-bodied predatory fish; less is known about the %MeHg in smaller-bodied individuals or those of different trophic guilds. This study analyzed MeHg and total Hg concentrations in the muscle of two large-bodied piscivores (walleye, northern pike), one large-bodied benthivore (white sucker), and two small-bodied forage fish (sculpins, shiners) across a broad size range...
July 19, 2018: Environmental Toxicology and Chemistry
Ashley N Parks, Michaela A Cashman, Monique M Perron, Lisa Portis, Mark G Cantwell, David R Katz, Kay T Ho, Robert M Burgess
Copper is a well-known toxic metal to marine organisms. In this investigation, we measured and compared the acute toxicity of several forms of copper (including nanocopper) amended into a marine sediment with mysids and amphipods. For all the forms of copper tested, toxicity, measured as the LC50, ranged from 708 to > 2400 mg Cu/kg (dry sediment) for mysids and 258 to 1070 mg Cu/kg (dry sediment) for amphipods. This article is protected by copyright. All rights reserved.
July 19, 2018: Environmental Toxicology and Chemistry
Carolin L Schultz, Elma Lahive, Alan Lawlor, Alison Crossley, Victor Puntes, Jason M Unrine, Claus Svendsen, David J Spurgeon
Engineered nanoparticles entering the environment are subject to various transformations that in turn influence how particles are presented to, and taken up by organisms. To understand the effect of soil properties on the toxicity of nanosilver to C. elegans toxicity assays were performed in pore water extracts from natural soils with varying organic matter content and pH using 3-8 nm un-functionalised (Ag 3-8Unf), 52 nm PVP-coated silver nanoparticles (Ag 52PVP) and AgNO3 as ionic silver. Effects on nanoparticle agglomeration and stability were investigated using UV-vis spectroscopy and asymmetric flow field-flow fractionation (AF4)...
July 12, 2018: Environmental Toxicology and Chemistry
Caitlin T Rumrill, David E Scott, Stacey L Lance
Species with complex life cycles are susceptible to environmental stressors across life stages, but the carryover and latent effects between stages remain understudied. For species with biphasic life histories, such as pond-breeding amphibians, delayed effects of aquatic conditions can influence terrestrial juveniles and adults directly or indirectly, usually mediated through fitness correlates such as body size. We collected adult southern toads (Anaxyrus terrestris) from two source populations - a natural reference wetland and a metal-contaminated industrial wetland - and exposed their offspring to two aquatic stressors - a metal contaminant, copper (Cu), and a dragonfly predator cue - in outdoor mesocosms (n = 24)...
July 9, 2018: Environmental Toxicology and Chemistry
James P Sanders, Natasha A Andrade, Upal Ghosh
Polymeric passive sampling devices are increasingly used to measure low-level, freely dissolved concentrations of hydrophobic organic contaminants in environmental waters. A range of polymers have been used for this purpose, and several different methods of accounting for nonequilibrium using performance reference compounds (PRCs) have been proposed. This study explores the practical impacts of these decisions in an applied context using results from a multi-year passive sampling surveillance of polychlorinated biphenyl (PCB) concentrations in sediment porewater at a contaminated marsh amended with activated carbon sorbent materials...
July 5, 2018: Environmental Toxicology and Chemistry
Benjamin M Westerhoff, David J Fairbairn, Mark L Ferrey, Adriana Matilla, Jordan Kunkel, Sarah M Elliott, Richard L Kiesling, Dustin Woodruff, Heiko L Schoenfuss
Urban stormwater is an important but incompletely characterized contributor to surface-water toxicity. The present study used five bioassays of two model organisms (Daphnia magna and fathead minnows, Pimephales promelas) to investigate stormwater toxicity and mitigation by full-scale iron-enhanced sand filters (IESF). Stormwater samples were collected from major stormwater conveyances and full-scale IESFs during four seasonal events (winter snowmelt; and spring, early summer, and late summer rainfalls) and analyzed for a diverse range of contaminants of emerging concern including pharmaceuticals, personal care products, industrial chemicals, and pesticides...
July 5, 2018: Environmental Toxicology and Chemistry
Glen Thursby, Keith Sappington, Matthew Etterson
Population modeling evaluations of pesticide exposure time series were compared to aspects of a currently used risk assessment process. The US Environmental Protection Agency's Office of Pesticide Programs models daily aquatic pesticide exposure values for 30 years in its risk assessments, but does not routinely make full use of the information in those time series. We used mysid shrimp Americamysis bahia toxicity and demographic data to demonstrate the value of a toxicokinetic-toxicodynamic model coupled with a series of matrix population models in risk assessment refinements...
July 5, 2018: Environmental Toxicology and Chemistry
Valerie Toteu Djomte, Raegyn B Taylor, Sunmao Chen, Kees Booij, C Kevin Chambliss
The effects of changing hydrodynamic conditions and changing temperatures on Polar Organic Chemical Integrative Sampler (POCIS) sampling rates (Rs ) were investigated for 12 crop protection chemicals. Exposure concentration was held constant in each laboratory experiment, and flow velocities were calculated from measured mass transfer coefficients of the water boundary layer near the surface of POCIS devices. Sampling rates at a given temperature generally increased by a factor of 2-5 between a stagnant condition and higher flow velocities (6-21 cm/s), but Rs for most compounds was essentially constant between the higher flow velocities...
July 5, 2018: Environmental Toxicology and Chemistry
Jongchul Kim, Jung-Ho Kang, Sung-Deuk Choi, Jiping Zhu, Yoon-Seok Chang
Polybrominated diphenyl ethers (PBDEs) have been banned or voluntarily withdrawn from commerce worldwide. Declining level of PBDEs in humans has been reported elsewhere, but not in Korea yet. In this study, seven individual PBDE congeners (BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154 and BDE-183) were monitored in the 103 human serum samples collected in 2006. The arithmetic mean and median values for the sum of the seven PBDEs (∑PBDEs) were 7.13 ng/g lipid and 6.70 ng/g lipid respectively. In addition, six pooled human serum samples collected in 2006, 2007, 2009, 2011, 2012 and 2013 were analyzed...
July 5, 2018: Environmental Toxicology and Chemistry
Paul McManus, Joshua Hortin, Anne J Anderson, Astrid R Jacobson, David W Britt, Joseph Stewart, Joan E McLean
The impact of copper oxide nanoparticles (CuO NPs) on crop production is dependent on the biogeochemistry of Cu in the rooting zone of the plant. This study addressed the metabolites in wheat root exudates that increased dissolution of CuO NPs, and whether solubility correlated with Cu uptake into the plant. Bread wheat (Triticum aestivum cv. Dolores) was grown for 10 d with 0 to 300 mg Cu/kg as CuO NPs in sand, a matrix deficient in Fe, Zn, Mn and Cu for optimum plant growth. Increased NP doses enhanced root exudation, including the Cu-complexing phytosiderophore, 2'-deoxymugineic acid (DMA), and corresponded to greater dissolution of the CuO NPs...
July 5, 2018: Environmental Toxicology and Chemistry
Christine A Bishop, Alison J Moran, Michelle C Toshack, Elizabeth Elle, France Maisonneuve, John E Elliott
To measure exposure to neonicotinoid and other pesticides in avian pollinators, we made novel use of cloacal fluid and fecal pellets from rufous (Selasphorus rufus) and Anna's (Calypte anna) hummingbirds living near blueberry fields in the Fraser River Valley and Vancouver Island, British Columbia, Canada. To examine on-farm exposure to pesticides in invertebrate pollinators, we also collected bumble bees native to Canada (Bombus mixtus, Bombus flavifrons, and Bombus melanopygus), their pollen, and blueberry leaves and flowers from within conventionally sprayed and organic blueberry farms...
July 5, 2018: Environmental Toxicology and Chemistry
Michael Y-T Lim, Richard G Manzon, Christopher M Somers, Douglas R Boreham, Joanna Y Wilson
During incubation, round whitefish embryos may experience fluctuating or elevated temperatures from natural (e.g. seasonal temperature changes) and/or anthropogenic sources. Anthropogenic sources like once-through cooling discharges from nuclear power plants can also expose embryos to chemicals (e.g. morpholine) and/or radiation. To examine the effects of these potential stressors on embryogenesis, round whitefish were incubated under fluctuating or constant temperatures, with morpholine or 137 Cs gamma rays...
July 2, 2018: Environmental Toxicology and Chemistry
Mary Ann Ottinger, Emma T Lavoie, Meredith E B Bohannon, Allegra M Marcel, Anna E Tschiffely, Kara B Duffy, Moira McKernan, Nichola Thompson, H Kasen Whitehouse, Kimya Davani, Marci Strauss, Donald E Tillitt, Josh Lipton, Karen M Dean
Studies were conducted to develop methods to assess the effects of a complex mixture of polychlorinated biphenyls (PCBs) in the domestic chicken (Gallus domesticus). Treatments were administered by egg injection to compare embryonic effects of an environmentally relevant PCB congener mixture in the domestic chicken over a range of doses. Chicken eggs were injected with a PCB mixture (PCB mix) with a profile similar to that found in avian eggs collected on the Upper Hudson River, NY at doses that spanned 0 - 98 µg/g egg...
June 27, 2018: Environmental Toxicology and Chemistry
David B Herbst, R Bruce Medhurst, Ned P R Black
Monitoring of benthic invertebrates in streams receiving acidic metal-contaminated water over 18-years revealed both degraded conditions and recovery along a network of downstream locations. Compared to reference streams, and over the course of clean-up remediation efforts below an abandoned open-pit sulfur mine in the central Sierra Nevada (California), improving water quality was accompanied by recovery of benthic communities at some sites. Years of high flow resulted in degraded biological status when acid mine drainage capture was incomplete and metals loading had increased with runoff...
June 25, 2018: Environmental Toxicology and Chemistry
David M Walters, Ryan R Otter, Johanna M Kraus, Marc A Mills
We investigated PCB contamination at the Ashtabula River Area of Concern (AOC) following remedial dredging using araneid and tetragnathid spiders. PCB concentrations remain elevated in the AOC compared to reference conditions. Patterns of contamination were strikingly similar between taxa, but were higher in tetragnathids at the most contaminated sites. Spider PCB homolog distributions identified two PCB sources to the AOC. Based on these findings, we recommend situations where these taxa can be used singularly, in concert, or combined into a composite "spider" sample to assess environmental contamination...
June 21, 2018: Environmental Toxicology and Chemistry
Julio Alberto Alegre Stelzer, Catiusa Kuchak Rosin, Luana Hainzenreder Bauer, Marilia Hartmann, Fernando Hepp Pulgati, Alexandre Arenzon
On the past few years, Fish Embryo Test (FET) became protagonist regarding the usage of "animal-friendly" protocols for ecotoxicological proposes. As OECD 236 FET has been widely applied on the scope of REACH (simple mixture exposures), but it is blindly worldwide spreading as a Whole Effluent Test (WET) - complex mixture exposures. However, comparative peer-reviewed data regarding FET's efficiency for WET is virtually absent. The primary objective of this paper is to compare OECD 236 with other worldwide used standard and slightly modified ecotoxicological protocols, providing a comprehensive overview of available tests for WET...
June 21, 2018: Environmental Toxicology and Chemistry
Dimitri Van de Perre, Ivo Roessink, Colin R Janssen, Erik Smolders, Frederik De Laender, Paul J Van den Brink, Karel A C De Schamphelaere
Ecotoxicological studies mainly consist of single-species experiments evaluating the effects of a single stressor. However, under natural conditions aquatic communities are exposed to a mixture of stressors. This study was set up to identify how the toxicity of zinc (Zn) is affected by increased temperature (T) and increased phosphorus supply (P) and how these interactions vary among species, functional groups, community structure and function. Aquatic microcosms were subjected to three Zn concentrations (background: no Zn added; 75 µg Zn/L and 300 µg Zn/L), two temperatures (16-19 °C and 21-24 °C) and 2 different P additions (low: 0...
June 21, 2018: Environmental Toxicology and Chemistry
Junmei Jia, Qiuwen Chen, Min Wang, Jianyun Zhang, Qitao Yi, Liuming Hu
To find the connections between microcystins (MCs) and phytoplankton community coupled with environmental factors, two cyanobacteria blooming lakes, Lake Taihu and Lake Yanghe, were investigated. Two years data, including water quality, phytoplankton, MCs and the congeners in both algal cells and water, were collected from the two lakes during 2013 and 2014. The results showed that the MC quota and MC release percentage were positively correlated with biodiversity of phytoplankton and the ratio of Chlorophyta/phytoplankton, but were negatively correlated with cyanobacteria abundance and the ratio of cyanobacteria/phytoplankton; the MC quota and MC release percentage were closely related to the intensity of competition between cyanobacteria and other phytoplankton; meanwhile, MCs played a role in competition between cyanobacteria and other phytoplankton...
June 20, 2018: Environmental Toxicology and Chemistry
Dong Zhou
With the increasing concerns regarding the toxic effects of bisphenol A (BPA), BPA has been gradually replaced by its analogues in the industrial applications, such as bisphenol S (BPS). As comparative toxicity evaluation of bisphenol analogs is scarce, it is necessary to conduct the comparative analysis. In this study, the model animal Caenorhabditis elegans (C. elegans) was used to evaluate low-concentration BPS toxicity, and 72-h exposure from L1 larvae was conducted. Multiple indicators at the physiological, biochemical and molecular levels were tested...
June 20, 2018: Environmental Toxicology and Chemistry
Adam Peters, Graham Merrington, Christian Schlekat, Karel De Schamphelaere, Jennifer Stauber, Graeme Batley, Andrew Harford, Rick van Dam, Ceiwen Pease, Tom Mooney, Michael Warne, Chris Hickey, Peter Glazebrook, John Chapman, Ross Smith, Rick Krassoi
Australian freshwaters have relatively low water hardness and different calcium to magnesium ratios compared with those in Europe. The hardness values of a substantial proportion of Australian freshwaters fall below the application boundary of the existing European nickel Biotic Ligand Models (NiBLMs) of 2 mg Ca/L. Toxicity testing was undertaken using Hydra viridissima to assess the predictive ability of the existing NiBLM for this species in extremely soft waters. This testing revealed an increased competitive effect of calcium and magnesium with nickel for binding to the biotic ligand in soft water (<10 mg CaCO3 /L) than at higher water hardness...
June 20, 2018: Environmental Toxicology and Chemistry
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