Betula platyphylla var. japonica (white birch) has heterophyllous leaves (i.e., early and late leaves) and is a typical pioneer tree species in northern Japan. Seedlings of white birch were exposed to ozone during two growing seasons, and measurements were carried out in the second year. Early leaves did not show an ozone-induced reduction in photosynthesis because of lower stomatal conductance resulting in higher avoidance capacity for ozone-induced stress. Also, an ozone-related increase in leaf nitrogen content may partly contribute to maintain the photosynthetic capacity in early leaves under elevated ozone in autumn. On the other hand, late leaves showed an ozone-induced decline of photosynthesis and early defoliation of leaves occurred. Also, smaller leaf size and higher stomatal density in late leaves were observed under elevated ozone. Differences in stress resistance to ozone may be related to differing functional roles of early and late leaves for birch species.

More than 2300 sediment pore water distribution coefficients (KPCBi ds) of 93 polychlorinated biphenyls (PCBs) were measured and modeled from sediments from Indiana Harbor and Ship Canal. KPCBi ds were calculated from previously reported bulk sediment values and newly analyzed pore water. PCBs in pore waters were measured using SPME PDMS-fiber and ∑PCB ranged from 41 to 1500 ng L−1. The resulting KPCBi ds were ∼1 log unit lower in comparison to other reported values. A simple model for the KPCBi d consisted of the product of the organic carbon fraction and the octanol–water partition coefficient and provided an excellent prediction for the measured values, with a mean square error of 0.09 ± 0.06. Although black carbon content is very high in these sediments and was expected to play an important role in the distribution of PCBs, no improvement was obtained when a two-carbon model was used.

The toxicity of atmospheric fine particulate matter (PM2.5) in Atlanta is assessed using freshwater rotifers (Brachionus calyciflorus). The PM-laden quartz filters were extracted in both water and methanol. Aerosol extracts were passed through a C-18 column to separate the PM components into hydrophobic and hydrophilic fractions. Toxicity data reported in the units of LC50 (concentration that kills 50% of the test population in 24 h) shows that ambient particles are toxic to the rotifers with LC50 values ranging from 5 to 400 μg of PM. The methanol extract of the aerosols was substantially more toxic (8 ± 6 times) to the rotifers compared to the water extracts. A sizeable fraction (>70%) of toxicity was found to be associated with the hydrophobic fraction of PM. However, none of the bulk aerosol species was strongly correlated with the LC50 values suggesting a complicated mechanism of toxicity probably involving synergistic interactions of various PM components.

We hypothesized that the photosynthetic performance of mangrove stands restored by the single planting of mangroves species would be lowered due to residual stressors. The photosynthetic parameters of the vegetation of three planted mangrove stands, each with a different disturbance history, were compared to reference sites and correlated with edaphic environmental variables. A permutational analysis of variance showed significant interaction when the factors were compared, indicating that the photosynthetic parameters of the restoration areas differed from the reference sites. A univariate analysis of variance showed that all the photosynthetic parameters differed between sites and treatments, except for photosynthetic efficiency (αETR). The combination of environmental variables that best explained the variations observed in the photosynthetic performance indicators were Cu, Pb and elevation disruptions. Fluorescence techniques proved efficient in revealing important physiological differences, representing a powerful tool for rapid analysis of the effectiveness of initiatives aimed at restoring coastal environments.

Metal toxicity to lettuce Lactuca sativa was determined following mixture exposure based on the concepts of concentration addition (CA) and response addition (RA). On the basis of conventional models assuming no interaction between mixture components, Ag+ was the most toxic, followed by Cu2+ and Zn2+. Furthermore, ion–ion interactions were included in quantitatively estimating toxicity of interactive mixtures of Cu2+–Zn2+ and Cu2+–Ag+ by linearly expanding the CA and RA models. About 80–92% of the variability in the root growth could be explained by this approach. Estimates by the extended models indicate significant alleviative effects of Zn2+ on Cu2+ toxicity whereas Cu2+ did not significantly affect Zn2+ toxicity. According to the extended CA model, Cu2+ significantly reduced Ag+ toxicity while Ag+ enhanced Cu2+ toxicity. Similar effects were not found by the extended RA model. These interactions might result from their individual uptake mechanisms and toxic actions as published in literature.

1H NMR metabolomics and conventional ecotoxicity endpoints were used to examine the response of earthworms exposed to petroleum hydrocarbons (PHCs) in soil samples collected from a site that was contaminated with crude oil from a pipeline failure in the mid-1990s. The conventional ecotoxicity tests showed that the soils were not acutely toxic to earthworms (average survival ≥90%), but some soil samples impaired reproduction endpoints by >50% compared to the field control soil. Additionally, metabolomics revealed significant relationships between earthworm metabolic profiles (collected after 2 or 14 days of exposure) and soil properties including soil PHC concentration. Further comparisons by partial least squares regression revealed a significant relationship between the earthworm metabolomic data (collected after only 2 or 14 days) and the reproduction endpoints (measured after 63 days). Therefore, metabolomic responses measured after short exposure periods may be predictive of chronic, ecologically relevant toxicity endpoints for earthworms exposed to soil contaminants.

Increasing metal pollution has drawn broad public attention in China due to severe environmental quality deterioration. However, so far, there has been no study to survey metal accumulation in Chinese farmland soil at the national scale. In this study, we determined 11 metals in farmland soils across the Mainland China. Our results indicated the concentrations of Pb, Cd, Zn, and Cu (10.1–184.2, 0.082–1.31, 20.2–321.9, 8.2–515.9 mg/kg, respectively) were elevated above their reference values. Moreover, these metals followed a similar geochemical distribution pattern. The accumulation of Pb, Cd, Zn, and Cu in soils may be associated with human activities for soil fertility. Cadmium had the highest pollution index (PI) of 5.28, and the average hazard quotients (HQs) for all the metals were below 1. Hence, except for Cd, the metals in Chinese arable soils are comparatively safe. Results from this study may provide valuable information for agricultural soil management in China.

Central European mountain bogs, among the most valuable and threatened of habitats, were exposed to intensive human impact during the 20th century. We reconstructed the subrecent water chemistry and water-table depths using diatom based transfer functions calibrated from modern sampling. Herbarium Sphagnum specimens collected during the period 1918–1998 were used as a source of historic diatom samples. We classified samples into hummocks and hollows according to the identity of dominant Sphagnum species, to reduce bias caused by uneven sampling of particular microhabitats. Our results provide clear evidence for bog pollution by grazing during the period 1918–1947 and by undocumented aerial liming in the early 90-ies. We advocate use of herbarized epibryon as a source of information on subrecent conditions in recently polluted mires.

Mixtures of polybrominated diphenyl ethers (PBDEs) have been widely used as additive flame retardants, and BDE-99 is one of the most predominant congeners found in the environment. BDE-99 has been reported in avian samples worldwide, yet knowledge of its toxicity to birds is minimal. We assessed the short- and long-term effects of nestling exposure to environmentally relevant levels of BDE-99 in a model passerine, the zebra finch. Early exposure to BDE-99 did not affect hematocrit, oxidative stress, or thyroid hormones in either the juvenile or adult stages, and there were no effects on chick growth or survival. BDE-99 exposure caused a dose-dependent delay in timing of reproduction, but there were no other effects on reproductive success. In zebra finches, endpoints related to reproductive behavior appear to be the most sensitive to BDE-99. However, passerines overall appear to be less sensitive than birds of prey or mammals to PBDE exposure.

A highly selective sample cleanup procedure combined with molecularly imprinted solid-phase extraction (MISPE) was developed for the isolation of gonyautoxins 2,3 (GTX2,3) from Alexandrium tamarense sample. The molecularly imprinted polymer microspheres (MIPMs) were prepared by suspension polymerization using caffeine as the dummy template molecule, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker and polyvinyl alcohol as the dispersive reagent. The polymer microspheres were used as a selective sorbent for the solid-phase extraction of gonyautoxins 2,3. An off-line MISPE method followed by high-performance liquid chromatography (HPLC) with fluorescence detection for the analysis of gonyautoxins 2,3 was established. Finally, the extract samples from Alexandrium tamarense were analyzed. The results showed the imprinted polymer microspheres exhibited high affinity and selectivity for gonyautoxins 2,3. The interference matrix in the extract were obviously cleaned by MISPE and the extraction efficiency of gonyautoxins 2,3 in the sample ranged from 81.74% to 85.86%.