Duo-molecularly imprinted polymer-coated magnetic particles for class-selective removal of endocrine-disrupting compounds from aqueous environment

The removal of steroid and phenolic endocrine-disrupting compounds (EDCs) from an aqueous environment was investigated using magnetic particles encapsulated by a duo-molecularly imprinted polymer (duo-MIP). The effect of environmental variables on the binding efficiency was studied. Experimental results showed that the amount of EDCs adsorbed was neither affected by up to 10.0 mM NaCl nor significantly interfered by up to 10.0 mg/L humic acid. Negligible influence was observed from pH 3.3 to pH 6.8, but a decrease started at pH 9. Freundlich isotherm parameters indicated binding capacities in the order of DES?>?E2?～?E1?>?BPA. The applicability of class-selective removal was verified using river water samples spiked with these EDCs at 10 μg/L; the binding efficiencies were 90, 90, 88, and 98 % for estrone (E1), 17β-estradiol (E2), bisphenol A (BPA), and diethylstilbestrol (DES), respectively. A reuse investigation verified constant binding capacities exhibiting <2 % reduction after seven cycles of regeneration.     

The Magnitude of Bias in the Measurement of PM25 Arising from Volatilization of Particulate Nitrate from Teflon Filters

ABSTRACT

Because the Federal Reference Method for PM₂₅ specifies the collection of ambient particles on Teflon filters, we have examined the loss of a known volatile species, particulate nitrate, during sampling. Data are presented from two studies in southern California for which parallel samples were collected by different methods. Differences in collected nitrate are modeled using an evaporation model based on the work of Zhang and McMurry. The average nitrate obtained from sampling with Teflon filters was 28% lower on average than that measured by denuded nylon filters. In contrast, cascade impactor samples were within 5% of the denuded nylon filter on average. A simple model is presented that accounts for the particulate nitrate loss from Teflon filters either by scavenging nitric acid and ammonia in the sampler inlet or by heating the filter substrate during sampling. The observed magnitude of loss is explained by any of the following situations: (1) 100% nitric acid and ammonia vapor loss in the inlet, (2) 5 °C heating of the filter substrate above ambient temperature during sampling, or (3) a combination of these factors, such as 50% vapor loss in the inlet and 3 °C heating of the filter.     

Kinetics of aerobic and anaerobic biomineralization of atrazine in surface and subsurface agricultural soils in Ohio

The purpose of this study was to assess atrazine mineralization in surface and subsurface samples retrieved from vertical cores of agricultural soils from two farm sites in Ohio. The Defiance site (NW-Ohio) was on soybean-corn rotation and Piketon (S-Ohio) was on continuous corn cultivation. Both sites had a history of atrazine application for at least a couple of decades. The clay fraction increased at the Defiance site and the organic matter and total N content decreased with depth at both sites. Mineralization of atrazine was assessed by measurement of ¹⁴CO₂ during incubation of soil samples with [U-ring-¹⁴C]-atrazine. Abiotic mineralization was negligible in all soil samples. Aerobic mineralization rate constants declined and the corresponding half-lives increased with depth at the Defiance site. Anaerobic mineralization (supplemented with nitrate) was mostly below the detection at the Defiance site. In Piketon samples, the kinetic parameters of aerobic and anaerobic biomineralization of atrazine displayed considerable scatter among replicate cores and duplicate biometers. In general, this study concludes that data especially for anaerobic biomineralization of atrazine can be more variable as compared to aerobic conditions and cannot be extrapolated from one agricultural site to another.     

Reconnecting to the Biosphere

Humanity has emerged as a major force in the operation of the biosphere, with a significant imprint on the Earth System, challenging social-ecological resilience. This new situation calls for a fundamental shift in perspectives, world views, and institutions. Human development and progress must be reconnected to the capacity of the biosphere and essential ecosystem services to be sustained. Governance challenges include a highly interconnected and faster world, cascading social-ecological interactions and planetary boundaries that create vulnerabilities but also opportunities for social-ecological change and transformation. Tipping points and thresholds highlight the importance of understanding and managing resilience. New modes of flexible governance are emerging. A central challenge is to reconnect these efforts to the changing preconditions for societal development as active stewards of the Earth System. We suggest that the Millennium Development Goals need to be reframed in such a planetary stewardship context combined with a call for a new social contract on global sustainability. The ongoing mind shift in human relations with Earth and its boundaries provides exciting opportunities for societal development in collaboration with the biosphere--a global sustainability agenda for humanity.     

Alternative reproductive tactics and the impact of local competition on sex ratios in the ant Hypoponera opacior

The ant Hypoponera opacior exhibits alternative reproductive morphs of males and females associated with distinct sexual behaviours. Our long-term study reports strong seasonality in sexual production with a mating season in early and one in late summer. Winged (alate) reproductives emerge in June, swarm during the monsoon season and establish new colonies independently. In contrast, wingless worker-like (ergatoid) reproductives that appear in late August mate within their natal or adjacent nests and either do not disperse or establish new nests close by. These divergent dispersal patterns allowed us to analyse the impact of local factors on investment strategies by comparing sex allocation between and within the two reproductive events. The optimal sex ratio for ergatoid reproductives should be influenced both by competition for matings between brothers (local mate competition) and rivalry among young locally dispersing queens for workers, nest sites or food (local resource competition). The greater importance of local resource competition was demonstrated both by a male-biased sex ratio for wingless sexuals and a stronger increase in the number of males with total sexual production than for the number of queens. Microsatellite analysis revealed that inter-nest variation in relatedness asymmetry cannot explain split sex ratios in the August generation. Instead, nests with related ergatoid males raised a male-biased sex ratio contrary to the expectations under local mate competition. In conclusion, male bias in wingless H. opacior indicates that local mate competition is less strong than local resource competition among ergatoid queens over the help of workers during nest foundation.     

Autumn migratory fuelling: a response to simulated magnetic displacements in juvenile wheatears, Oenanthe oenanthe

Recent experiments exposing migratory birds to altered magnetic fields simulating geographical displacements have shown that the geomagnetic field acts as an external cue affecting migratory fuelling behaviour. This is the first study investigating fuel deposition in relation to geomagnetic cues in long-distance migrants using the western passage of the Mediterranean region. Juvenile wheatears (Oenanthe oenanthe) were exposed to a magnetically simulated autumn migration from southern Sweden to West Africa. Birds displaced parallel to the west of their natural migration route, simulating an unnatural flight over the Atlantic Ocean, increased their fuel deposition compared to birds experiencing a simulated migration along the natural route. These birds, on the other hand, showed relatively low fuel loads in agreement with earlier data on wheatears trapped during stopover. The experimental displacement to the west, corresponding to novel sites in the Atlantic Ocean, led to a simulated longer distance to the wintering area, probably explaining the observed larger fuel loads. Our data verify previous results suggesting that migratory birds use geomagnetic cues for fuelling decisions and, for the first time, show that birds, on their first migration, can use geomagnetic cues to compensate for a displacement outside their normal migratory route, by adjusting fuel deposition.     

Reducing the Maladaptive Attractiveness of Solar Panels to Polarotactic Insects

Abstract: Human‐made objects (e.g., buildings with glass surfaces) can reflect horizontally polarized light so strongly that they appear to aquatic insects to be bodies of water. Insects that lay eggs in water are especially attracted to such structures because these insects use horizontal polarization of light off bodies of water to find egg‐laying sites. Thus, these sources of polarized light can become ecological traps associated with reproductive failure and mortality in organisms that are attracted to them and by extension with rapid population declines or collapse. Solar panels are a new source of polarized light pollution. Using imaging polarimetry, we measured the reflection–polarization characteristics of different solar panels and in multiple‐choice experiments in the field we tested their attractiveness to mayflies, caddis flies, dolichopodids, and tabanids. At the Brewster angle, solar panels polarized reflected light almost completely (degree of polarization d ≈100%) and substantially exceeded typical polarization values for water (d ≈30–70%). Mayflies (Ephemeroptera), stoneflies (Trichoptera), dolichopodid dipterans, and tabanid flies (Tabanidae) were the most attracted to solar panels and exhibited oviposition behavior above solar panels more often than above surfaces with lower degrees of polarization (including water), but in general they avoided solar cells with nonpolarizing white borders and white grates. The highly and horizontally polarizing surfaces that had nonpolarizing, white cell borders were 10‐ to 26‐fold less attractive to insects than the same panels without white partitions. Although solar panels can act as ecological traps, fragmenting their solar‐active area does lessen their attractiveness to polarotactic insects. The design of solar panels and collectors and their placement relative to aquatic habitats will likely affect populations of aquatic insects that use polarized light as a behavioral cue.     

Hepatic effects of yttrium oxide nanoflowers: in vitro risk evaluation

Yttrium oxide nanoflowers were prepared by a hydrothermal technique, and X-ray diffraction and scanning electron microscopy were used to determine their structures. The cytotoxic and genotoxic potentials of aqueous dispersions of the nanoflowers to cultured primary rat hepatocytes were examined at concentrations up to 500 mg L^?1 for 72 h. Cell viability was determined by monitoring the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, release of lactate dehydrogenase, and uptake of neutral red. Genotoxicity was assessed by the liver micronucleus assay. Exposure to Y₂O₃ nanoflowers at concentrations lower than 100 mg L^?1 did not lead to any cytotoxicity or genotoxicity. At higher concentrations (200, 400, and 500 mg L^?1), cell viability decreased and induction of micronuclei increased (400 and 500 mg L^?1).     

Stabilization of metal processing plant sludge via sequential application of phytoremediation and pyrolysis

The aim of this study is to evaluate the metal removal ability of three different plants from metal processing sludge containing Pb, Cd, and Zn. Therefore, phytoremediation and pyrolysis were sequentially applied. In the phytoremediation applications, sunflower (Helianthus annuus), corn (Zea mays), and rape (Brassica napus) seeds were sown in sludge/soil mixtures at four different levels (25/75, 50/50, 75/25, 100/0). The chelating agent, ethylenediaminetetraacetic acid, was added to the mixtures for plant uptake during phytoremediation. At the phytoremediation stage, it was noted that rape was the most effective plant for the mixture of 75/25 sludge/soil, with metal removal efficiencies ranging between 80%–90%. At the pyrolysis stage, after harvesting, contaminated plants grown in a 75/25 sludge/soil mixture were pyrolyzed at 500 °C, with a heating rate of 35 °C/min. The results show that 60%–90% of the initial metal content was held by the solid product. In addition to this, it can be concluded that pyrolysis stabilizes metals into a solid product and that this solid product can be safely landfilled as inert waste since its toxicity leaching value is lower than the limit values.     

Spatial patterns and environmental correlates in leaf-associated epifaunal assemblages of temperate seagrass (<Emphasis Type=Italic>Zostera marina</Emphasis>) meadows

We estimated and tested variability of seagrass leaf-associated epifaunal assemblages at a range of scales. Sampling was performed in 36 seagrass (Zostera marina) meadows within three regions along the Swedish west coast following a hierarchical design (samples separated by 10 s m, km or 100 km). Results showed strongest variability (43–81%) at the intermediate amongst-meadow (km) scale using biomass of functional categories, while considering taxa composition the within-meadow (10 s m) scale contributed most to variability (60%). Using functional categories, we found that embayment exposure and seagrass shoot density were the most important predictor variables explaining part of the variability in biomass of suspension feeders (bivalves and barnacles) and grazers. In contrast, variability in epifaunal taxa composition was predicted mainly by sediment chemistry, substratum coverage and geographical positioning. Our findings suggest that models to develop predictive power and mechanistic understanding should focus on variables and processes varying at small and intermediate scales rather than those varying at larger scales.