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Aims: To investigate the associations of serum trace elements (iron, zinc, and copper) between women with different pregnancy outcomes. Methods: About 774 pregnant women who came to The Fourth Hospital of Shijiazhuang for prenatal examination were investigated. The concentrations of trace elements in the serum of pregnant women in the third trimester were collected. Multivariate logistic regression was used to analyze the relationship between serum trace element levels and the different pregnancy outcomes. Multiple linear regression was used to analyze the relationship between serum trace elements levels and hypersensitive‐C‐reactive‐protein. Results: Results of the multiple logistic regression showed that zinc, copper and copper/zinc ratio were found to be associated with the risk of gestational diabetes mellitus, and zinc was a protective factor (p = 0.002) while copper and copper/zinc ratio as risk factors (p = 0.030 and p = 0.001, respectively) after adjusting for major confounders. It was found that iron and zinc were negatively associated with the risk of moderate or severe anemia (p = 0.022 and p = 0.001, respectively). In contrast, the copper/zinc ratio was positively related to the risk of moderate or severe anemia (p = 0.021). The adjusted relationships between copper and copper/zinc ratio with premature rupture of membranes were statistically significant (p = 0.007 and p = 0.037). Iron and zinc were negatively associated with the risk of chorioamnionitis, while copper and copper/zinc ratio were positively associated with the risk of chorioamnionitis (all p < 0.05). Conclusions: Serum iron, zinc and copper levels are closely related to pregnancy outcomes. [ABSTRACT FROM AUTHOR]

This article is a Commentary on Scholz et al. (2021), 232: 2138–2151. [ABSTRACT FROM AUTHOR]

Summary: Cable bacteria are sulfide‐oxidising, filamentous bacteria that reduce toxic sulfide levels, suppress methane emissions and drive nutrient and carbon cycling in sediments. Recently, cable bacteria have been found associated with roots of aquatic plants and rice (Oryza sativa). However, the extent to which cable bacteria are associated with aquatic plants in nature remains unexplored.Using newly generated and public 16S rRNA gene sequence datasets combined with fluorescence in situ hybridisation, we investigated the distribution of cable bacteria around the roots of aquatic plants, encompassing seagrass (including seagrass seedlings), rice, freshwater and saltmarsh plants.Diverse cable bacteria were found associated with roots of 16 out of 28 plant species and at 36 out of 55 investigated sites, across four continents. Plant‐associated cable bacteria were confirmed across a variety of ecosystems, including marine coastal environments, estuaries, freshwater streams, isolated pristine lakes and intensive agricultural systems. This pattern indicates that this plant–microbe relationship is globally widespread and neither obligate nor species specific.The occurrence of cable bacteria in plant rhizospheres may be of general importance to vegetation vitality, primary productivity, coastal restoration practices and greenhouse gas balance of rice fields and wetlands. See also the Commentary on this article by Cardini & Malkin, 232: 1897–1900. [ABSTRACT FROM AUTHOR]

Equilibrium sampling based on silicone polydimethylsiloxane (PDMS) has been used to determine the concentrations of freely dissolved hydrophobic organic compounds (HOCs) and assess the thermodynamic potentials for bioaccumulation of these compounds in the aquatic environment. This allows the use of PDMS‐based sampling techniques in assisting conventional sampling and extraction methods for the determination of the concentrations of HOCs in aquaculture products. The present study is an ex situ demonstration of how well PDMS can inform the tissue residues and dietary risks of legacy or current‐use organic chemicals in aquaculture species from farm ponds in eastern China. For legacy contaminants such as polybrominated diphenyl ethers (PBDEs, n = 10), good agreement between the predicted concentrations based on PDMS and the measured lipid‐normalized concentrations was observed for 60% of the studied biota, including both pelagic and benthic species. For pesticides currently used, such as pyrethroid (PE) (n = 4) and organophosphate pesticides (OPPs, n = 7), the measured tissue residues were consistently higher than those predicted by PDMS, possibly caused by the continuous input from the surroundings. For the organochlorine pesticides (OCPs, n = 5), the only detected chemical was also underestimated. Adjusted by ingestion rates of aquaculture products and toxicology data, the target hazard quotients of these chemicals predicted from PDMS were generally comparable to those derived from measured concentrations in tissue because of the predominance of PBDEs. Overall, PDMS‐based equilibrium sampling offered an alternative approach for the prediction of tissue residues and dietary risks of PBDEs. Moreover, it should be applied with caution for PEs, OPPs, and OCPs. Improving the application of PDMS for these chemicals in farm ponds warrants future study. Environ Toxicol Chem 2021;40:79–87. © 2020 SETAC [ABSTRACT FROM AUTHOR]

BACKGROUND Arsenic pollution of water supplies is a global problem of environmental concern. Among inorganic species, trivalent arsenite, As(III), is the most toxic and difficult to remove. Conventional treatments usually involve the pre‐oxidation to pentavalent arsenic, As(V); however, this study is focused on the direct removal of aqueous arsenite species by selective adsorption. RESULTS: Sulfur‐containing adsorbents were prepared from mesostructured SBA‐15 silica by functionalization with propylthiol chains. The sulfur content of the synthetized materials, denoted as SBA‐15‐SH‐x, reached 4 mmol g−1. Kinetics and equilibrium batch experiments showed that all materials were excellent As(III) adsorbents, with maximum capacity as high as 0.46 mmol g−1, superior to literature values for comparable materials. The pH influence was significant and the best performance occurred at pH 8. A complementary pelletized material was designed and synthetized to explore the potential use of the adsorbents in the treatment of water streams polluted with arsenic through fixed‐bed column experiments. The breakthrough curves obtained in different operative conditions evidenced the viability of the process. CONCLUSIONS: SBA‐15‐SH‐x materials evaluated in this work exhibited very good performance for aqueous As(III) removal by direct adsorption without previous oxidation to As(V). The suitability of the materials was demonstrated through kinetics, equilibrium, and fixed‐bed column adsorption experiments. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Fertilizers containing phosphate (PO43−) are commonly used within the agricultural industry and are known to increase the bioavailability and mobility of metalloids like arsenic (As). This may increase plant uptake of As and hence pose a risk to human health. Arsenic and antimony (Sb) often co‐occur in contaminated soils; however, little is known about the interactions between As and Sb with PO43− on their bioavailability, accumulation, and toxicity in plants. The present study investigated individual and combined As and Sb–contaminated soils across 2 soil PO43− concentrations using a commonly consumed leafy vegetable, choy sum (Brassica chinensis var. parachinensis). Increased soil PO43− had no clear influence on the bioavailability of As or Sb (derived from a sequential extraction procedure). At high PO43− concentration, B. chinensis accumulated higher amounts of As in the shoots and roots in both individual and co‐contaminated soil, whereas Sb accumulation increased only when Sb was the only contaminant. When As was the only contaminant, the translocation of As from roots to shoots decreased as soil PO43− increased. Increased soil PO43− had no influence on Sb translocation from root to shoot. Although As was toxic (impaired growth) at low PO43− soil concentration, no toxicity was observed in the high‐PO43− soil. No toxicity was observed for Sb in either low‐ or high‐PO43− soils. Increased soil PO43− concentration ameliorated or masked As toxicity to plant growth and led to higher As concentration in the plant's edible parts. The addition of high soil PO43− concentrations ameliorated or masked As toxicity to plant growth in both individually and As + Sb co‐contaminated soil; however, the plant's edible parts accumulated higher As and Sb concentrations. Environ Toxicol Chem 2020;39:1233–1243. © 2020 SETAC [ABSTRACT FROM AUTHOR]

We explored the concept of equilibrium passive sampling for methylmercury (MeHg) using the strategy developed for hydrophobic organic chemicals. Passive sampling should allow prediction of the concentration of the chemically labile fraction of MeHg in sediment porewaters based on equilibrium partitioning into the sampler, without modeling diffusion rates through the sampler material. Our goals were to identify sampler materials with the potential to mimic MeHg partitioning into animals and sediments and provide reversible sorption in a time frame appropriate for in situ samplers. Candidate materials tested included a range of polymers embedded with suitable sorbents for MeHg. The most promising were activated carbon (AC) embedded in agarose, thiol–self‐assembled monolayers on mesoporous supports embedded in agarose, and cysteine‐functionalized polyethylene terephthalate, which yielded log sampler–water partition coefficients of 2.8 to 5 for MeHgOH and MeHg complexed with dissolved organic matter (Suwannee River humic acid). Sampler equilibration time in sediments was approximately 1 to 2 wk. Investigation of the MeHg accumulation mechanism by AC embedded in agarose suggested that sampling was kinetically influenced by MeHg interactions with AC particles and not limited by diffusion through the gel for this material. Also, AC exhibited relatively rapid desorption of Hg and MeHg, indicating that this sorbent is capable of reversible, equilibrium measurements. In sediment:water microcosms, porewater concentrations made with isotherm‐calibrated passive samplers agreed within a factor of 2 (unamended sediment) or 4 (AC‐amended sediment) with directly measured concentrations. The present study demonstrates a potential new approach to passive sampling of MeHg. Environ Toxicol Chem 2020;39:323–334. © 2019 SETAC [ABSTRACT FROM AUTHOR]

Anticipating, identifying, and prioritizing strategic needs represent essential activities by research organizations. Decided benefits emerge when these pursuits engage globally important environment and health goals, including the United Nations Sustainable Development Goals. To this end, horizon scanning efforts can facilitate identification of specific research needs to address grand challenges. We report and discuss 40 priority research questions following engagement of scientists and engineers in North America. These timely questions identify the importance of stimulating innovation and developing new methods, tools, and concepts in environmental chemistry and toxicology to improve assessment and management of chemical contaminants and other diverse environmental stressors. Grand challenges to achieving sustainable management of the environment are becoming increasingly complex and structured by global megatrends, which collectively challenge existing sustainable environmental quality efforts. Transdisciplinary, systems‐based approaches will be required to define and avoid adverse biological effects across temporal and spatial gradients. Similarly, coordinated research activities among organizations within and among countries are necessary to address the priority research needs reported here. Acquiring answers to these 40 research questions will not be trivial, but doing so promises to advance sustainable environmental quality in the 21st century. Environ Toxicol Chem 2019;38:1606–1624. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC. [ABSTRACT FROM AUTHOR]

This study evaluated potential effects of mercury (Hg) on benthic macroinvertebrates in the South River, Virginia, USA. The study used a multiple lines of evidence approach, including spatially and temporally matched sediment chemistry, biological, and toxicological information (Sediment Quality Triad), exposure and effect analysis in bulk and interstitial sediment and interstitial water, and critical body residue analysis. Ten‐day Chironomus dilutus and Hyalella azteca toxicity tests established site‐specific no‐effect concentrations (NOEC) at 18.9 μg/g total Hg (THg) and 102 ng/g methylmercury (MeHg). However, the benthic community at these locations was impaired, with lower mayfly and caddisfly composition. Few locations had concentrations of THg and MeHg that exceeded the NOEC in bulk or interstitial sediment. The THg concentrations in interstitial water were far below concentrations expected to reduce survival in benthic invertebrates, and only a low percentage of samples exceeded sublethal (growth) low‐effect concentrations (LOEC) for THg or MeHg. The THg concentrations in invertebrate tissue did not exceed the NOEC or LOEC in the South River, and MeHg concentrations exceeded the LOEC at all locations, including those with no evidence of benthic impairment, illustrating the uncertainty associated with this line of evidence. Finally, statistical modeling that evaluated diversity of sensitive invertebrate species as a function of Hg exposure, geomorphological parameters, and physicochemical variables indicated that physicochemical and geomorphological parameters were most predictive of benthic community; where Hg was indicated, we were unable to distinguish between models with or without interstitial water Hg. Overall, the lines of evidence indicate that Hg, while clearly toxic to invertebrates at sufficiently high exposure concentrations, is not negatively impacting invertebrate communities in the South River. This study illustrates the difficulty of assessing risks to invertebrates using traditional tools of risk assessment and identifies critical gaps in knowledge that complicate the management of Hg risk. Integr Environ Assess Manag 2019;00:000–000. © 2019 SETAC Key Points: Effects of Hg exposure were assessed in relatively intact natural invertebrate populations at the high end of environmental exposure range.Endpoints included measures of effect at the individual and community level.Despite elevated exposures, effects on invertebrates were not observed or were not distinguishable from differences due to habitat.The study provides an example of resiliency of invertebrate populations and limitations of traditional risk assessment tools. [ABSTRACT FROM AUTHOR]

Evaluations of sediment quality conditions are commonly conducted using whole-sediment chemistry analyses but can be enhanced by evaluating multiple lines of evidence, including measures of the bioavailable forms of contaminants. In particular, porewater chemistry data provide information that is directly relevant for interpreting sediment toxicity data. Various methods for sampling porewater for trace metals and dissolved organic carbon (DOC), which is an important moderator of metal bioavailability, have been employed. The present study compares the peeper, push point, centrifugation, and diffusive gradients in thin films (DGT) methods for the quantification of 6 metals and DOC. The methods were evaluated at low and high concentrations of metals in 3 sediments having different concentrations of total organic carbon and acid volatile sulfide and different particle-size distributions. At low metal concentrations, centrifugation and push point sampling resulted in up to 100 times higher concentrations of metals and DOC in porewater compared with peepers and DGTs. At elevated metal levels, the measured concentrations were in better agreement among the 4 sampling techniques. The results indicate that there can be marked differences among operationally different porewater sampling methods, and it is unclear if there is a definitive best method for sampling metals and DOC in porewater. Environ Toxicol Chem 2017;36:2906-2915. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. [ABSTRACT FROM AUTHOR]

A diffusive gradient in thin films (DGT) is an in situ sampling technique for the quantitative analysis of contaminant concentrations that is based on the diffusion and adsorption of contaminants on to resin gels. In the present study, a DGT technique was applied to measure total mercury (Hg) and monomethylmercury (MMHg) concentrations in lake and coastal sediment porewaters and compare them with those from ex situ sediment centrifugation. To calculate the total Hg and MMHg concentrations in porewater using the DGT method, the diffusion coefficients of Hg species in a diffusive gel medium was first determined, and then total Hg and MMHg depth profiles were measured using the experimentally determined diffusion coefficients. Using the diffusion coefficients for artificial lake and estuarine waters containing inorganic salts, rather than those for lake and estuarine waters containing Suwannee River humic acid (∼5 mg C L−1), the DGT method demonstrated similar Hg and MMHg profiles to those using the centrifugation method. Based on the need for fine vertical resolution and high metal concentrations to be collected, DGT is suggested to be a reliable method for determining Hg(II) and MMHg depth profiles in sediment porewater. Environ Toxicol Chem 2016;35:348-356. © 2015 SETAC [ABSTRACT FROM AUTHOR]

It is well documented that using exhaustive chemical extractions is not an effective means of assessing exposure of hydrophobic organic compounds in sediments and that bioavailability-based techniques are an improvement over traditional methods. One technique that has shown special promise as a method for assessing the bioavailability of hydrophobic organic compounds in sediment is the use of Tenax-extractable concentrations. A 6-h or 24-h single-point Tenax-extractable concentration correlates to both bioaccumulation and toxicity. This method has demonstrated effectiveness for several hydrophobic organic compounds in various organisms under both field and laboratory conditions. In addition, a Tenax bioaccumulation model was developed for multiple compounds relating 24-h Tenax-extractable concentrations to oligochaete tissue concentrations exposed in both the laboratory and field. This model has demonstrated predictive capacity for additional compounds and species. Use of Tenax-extractable concentrations to estimate exposure is rapid, simple, straightforward, and relatively inexpensive, as well as accurate. Therefore, this method would be an invaluable tool if implemented in risk assessments. Environ Toxicol Chem 2015;34:1445-1453. © 2015 SETAC [ABSTRACT FROM AUTHOR]

Lacustrine groundwater discharge (LGD) transports nutrients from a catchment to a lake, which may fuel eutrophication, one of the major threats to our fresh waters. Unfortunately, LGD has often been disregarded in lake nutrient studies. Most measurement techniques are based on separate determinations of volume and nutrient concentration of LGD: Loads are calculated by multiplying seepage volumes by concentrations of exfiltrating water. Typically low phosphorus (P) concentrations of pristine groundwater often are increased due to anthropogenic sources such as fertilizer, manure or sewage. Mineralization of naturally present organic matter might also increase groundwater P. Reducing redox conditions favour P transport through the aquifer to the reactive aquifer-lake interface. In some cases, large decreases of P concentrations may occur at the interface, for example, due to increased oxygen availability, while in other cases, there is nearly no decrease in P. The high reactivity of the interface complicates quantification of groundwater-borne P loads to the lake, making difficult clear differentiation of internal and external P loads to surface water. Anthropogenic sources of nitrogen (N) in groundwater are similar to those of phosphate. However, the environmental fate of N differs fundamentally from P because N occurs in several different redox states, each with different mobility. While nitrate behaves essentially conservatively in most oxic aquifers, ammonium's mobility is similar to that of phosphate. Nitrate may be transformed to gaseous N2 in reducing conditions and permanently removed from the system. Biogeochemical turnover of N is common at the reactive aquifer-lake interface. Nutrient loads from LGD were compiled from the literature. Groundwater-borne P loads vary from 0.74 to 2900 mg PO4-P m−2 year−1; for N, these loads vary from 0.001 to 640 g m−2 year−1. Even small amounts of seepage can carry large nutrient loads due to often high nutrient concentrations in groundwater. Large spatial heterogeneity, uncertain areal extent of the interface and difficult accessibility make every determination of LGD a challenge. However, determinations of LGD are essential to effective lake management. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Shoeprints are an important source of information for criminal investigation. Therefore, an increasing number of automatic shoeprint recognition methods have been proposed for detecting the corresponding shoe models. However, comprehensive comparisons among the methods have not previously been made. In this study, an extensive set of methods proposed in the literature was implemented, and their performance was studied in varying conditions. Three datasets of different quality shoeprints were used, and the methods were evaluated also with partial and rotated prints. The results show clear differences between the algorithms: while the best performing method, based on local image descriptors and RANSAC, provides rather good results with most of the experiments, some methods are almost completely unrobust against any unidealities in the images. Finally, the results demonstrate that there is still a need for extensive research to improve the accuracy of automatic recognition of crime scene prints. [ABSTRACT FROM AUTHOR]

The rapid redox transformation of arsenic (As) species in waters presents a great environmental challenge in the accurate determination of its concentration and toxicity. The motivation of the present study was therefore to develop a method for rapid on-site separation of As(V) and As(III) in various aqueous matrices. The authors synthesized a thiol-modified sand (T-sand) that selectively removed As(III) but did not adsorb As(V). The novel application of this T-sand in a disposable cartridge was able to successfully separate As(V) (37-970 µg L−1) and As(III) (not detected to 488 µg L−1) in 23 groundwater samples collected in areas with naturally occurring As. The As speciation results determined with T-sand separation in the field were consistent with those obtained using high-performance liquid chromatography-atomic fluorescence spectrometry. Furthermore, the T-sand cartridge was applicable in a wide variety of matrices, including groundwater, leachants of the toxicity-characteristic leaching procedure, and extracts from the California waste extraction test; sequential extraction test; and in vitro gastrointestinal extraction. This easy-to-use separation method is especially suitable for routine field monitoring of As speciation. Environ Toxicol Chem 2014;33:1692-1696. © 2014 SETAC [ABSTRACT FROM AUTHOR]

ABSTRACT Passive sampling methods (PSMs) allow the quantification of the freely dissolved concentration ( Cfree) of an organic contaminant even in complex matrices such as sediments. Cfree is directly related to a contaminant's chemical activity, which drives spontaneous processes including diffusive uptake into benthic organisms and exchange with the overlying water column. Consequently, Cfree provides a more relevant dose metric than total sediment concentration. Recent developments in PSMs have significantly improved our ability to reliably measure even very low levels of Cfree. Application of PSMs in sediments is preferably conducted in the equilibrium regime, where freely dissolved concentrations in the sediment are well-linked to the measured concentration in the sampler via analyte-specific partition ratios. The equilibrium condition can then be assured by measuring a time series or a single time point using passive samplers with different surface to volume ratios. Sampling in the kinetic regime is also possible and generally involves the application of performance reference compounds for the calibration. Based on previous research on hydrophobic organic contaminants, it is concluded that Cfree allows a direct assessment of 1) contaminant exchange and equilibrium status between sediment and overlying water, 2) benthic bioaccumulation, and 3) potential toxicity to benthic organisms. Thus, the use of PSMs to measure Cfree provides an improved basis for the mechanistic understanding of fate and transport processes in sediments and has the potential to significantly improve risk assessment and management of contaminated sediments. Integr Environ Assess Manag 2014;10:197-209. © 2014 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Objective To examine the effects of injectable vitamins A, D and E at feedlot entry on health and growth rate and the effects of injectable vitamin C at the time of treatment for bovine respiratory disease (BRD) on cattle health. Design Systematic allocation of 2465 cattle at feedlot entry to: a commercial vitamin A, D and E preparation at the label dose rate; commercial vitamin A, D and E at twice the label dose rate; a formulation with no vitamin D, a lower concentration of vitamin A and a higher concentration of vitamin E; and the oil-based carrier alone at volumes corresponding to the above treatments. Comparisons of growth rate, disease and mortality were made between the groups at the conclusion of the feeding period. In a separate experiment, 176 cattle were alternately administered injectable vitamin C at the time of treatment for BRD, or were not injected with vitamin C, and mortality was compared between the groups. Results There were no differences between cattle administered vitamin A, D and E at feedlot entry and the controls in growth rate (P = 0.11), all diseases (P = 0.99), BRD (P = 0.60) or mortalities (P = 0.95). Cattle treated with the higher vitamin E and lower vitamin A preparation had a higher (P = 0.02) incidence of anorexia than the other groups. Fewer cattle treated with 5 g of vitamin C by intramuscular injection at the time of treatment with antibiotics for BRD subsequently died (P = 0.04). Conclusions The routine injection of cattle with vitamins A, D and E at feedlot entry is unlikely to result in improvements in health and growth rate where cattle are provided with these vitamins in their diets at concentrations equal to the National Research Council recommendations. Mortality rate in cattle diagnosed with BRD may be reduced by intramuscular injection of vitamin C at the time of treatment with antibiotics. [ABSTRACT FROM AUTHOR]

Proposes corrections for estimating degrees of freedom in the interspecific allometry. Phylogenetic constraint; Degrees of freedom; Nested analysis of variance.

Examines the factors that affect the modular demography of Vallisneria americana. Effect of trichloroethylene on Vallisneria americana; Factors that determine the ability of plants to survive contaminant stress.