Bisphenol A (BPA) is widely used industrially to produce polycarbonate plastics and epoxy resins. Numerous studies document the harmful effects caused by low-dose BPA exposure especially on nervous systems and behavior in experimental animals such as mice and rats. Here, we exposed embryos of a model chordate, Ciona intestinalis, to seawater containing BPA to evaluate adverse effects on embryonic development and on the swimming behavior of subsequent larvae. Ciona is ideal because its larva develops rapidly and has few cells. The rate of larval hatching decreased in a dose-dependent manner with exposures to BPA above 3 μM; swimming behavior was also affected in larvae emerging from embryos exposed to 1 μM BPA. Adverse effects were most severe on fertilized eggs exposed to BPA within 7 h post-fertilization. Ciona shares twelve nuclear receptors with mammals, and BPA is proposed to disturb the physiological functions of one or more of these.

The effect of different surfactants on the transport of multiwalled carbon nanotubes (MWCNTs) in quartz sand-packed columns was firstly investigated under various conditions. The stable plateau values (Cmax) of the breakthrough curves (BTCs), critical PVs (the number of pore volumes of infusions needed to reach the Cmax), maximum transport distances (Lmax), deposition rate coefficients (kd) and retention rates were calculated to compare the transport and retention of MWCNTs under various conditions. Stability of the MWCNT suspensions as a function of the influencing factors was examined to reveal the underlying mechanism of the MWCNT retention. Results showed that MWCNTs suspended by different surfactants presented different BTCs; the MWCNT transport increased with increasing sand size and MWCNT concentration; high flow velocity was favorable for the MWCNT transport, while high Ca2+ concentration and low pH were unfavorable for the transport; hetero-aggregation, straining and site blocking occurred during the transport.

In February 2011 a MW 6.3 earthquake in Christchurch, New Zealand inundated urban waterways with sediment from liquefaction and triggered sewage spills. The impacts of, and recovery from, this natural disaster on the stream biogeochemistry and biology were assessed over six months along a longitudinal impact gradient in an urban river. The impact of liquefaction was masked by earthquake triggered sewage spills (∼20,000 m3 day−1 entering the river for one month). Within 10 days of the earthquake dissolved oxygen in the lowest reaches was <1 mg l−1, in-stream denitrification accelerated (attenuating 40–80% of sewage nitrogen), microbial biofilm communities changed, and several benthic invertebrate taxa disappeared. Following sewage system repairs, the river recovered in a reverse cascade, and within six months there were no differences in water chemistry, nutrient cycling, or benthic communities between severely and minimally impacted reaches. This study highlights the importance of assessing environmental impact following urban natural disasters.

The vast use of silver nanoparticles (AgNPs) mandates thorough investigation of their impact on biosystems at various levels. The cytotoxicity of PVP coated-AgNPs to pollen, the aploid male gametophyte of higher plants, has been assessed here for the first time. The negative effects of AgNPs include substantial decreases in pollen viability and performance, specific ultrastructural alterations, early changes in calcium content, and unbalance of redox status. Ag+ released from AgNPs damaged pollen membranes and inhibited germination to a greater extent than the AgNPs themselves. By contrast, the AgNPs were more potent at disrupting the tube elongation process. ROS deficiency and overproduction were registered in the Ag+- and AgNP-treatment, respectively. The peculiar features of AgNP toxicity reflected their specific modes of interaction with pollen surface and membranes, and the dynamic exchange between coating (PVP) and culture medium. In contrast, the effects of Ag+ were most likely induced through chemical/physicochemical interactions.

Historic emissions from two zinc smelters have injured the forest on Blue Mountain near Palmerton, Pennsylvania, USA. Seedlings of soybeans and five tree species were grown in a greenhouse in a series of mixtures of smelter-contaminated and reference soils and then phytotoxic thresholds were calculated. As little as 10% Palmerton soil mixed with reference soil killed or greatly stunted seedlings of most species. Zinc was the principal cause of the phytotoxicity to the tree seedlings, although Mn and Cd may also have been phytotoxic in the most contaminated soil mixtures. Calcium deficiency seemed to play a role in the observed phytotoxicity. Exposed soybeans showed symptoms of Mn toxicity. A test of the effect of liming on remediation of the Zn and Mn phytotoxicity caused a striking decrease in Sr-nitrate extractable metals in soils and demonstrated that liming was critical to remediation and restoration.

This study analyses 1800 years of heavy metal accumulation in a remote alpine lake experiencing long-range atmospheric contamination and additional inputs of Ag from cloud seeding. In comparison to previous work undertaken on peats, lake sediments show limited post-industrial metal enrichment with enrichment factors of Ag: 1.3, Pb: 1.3, Zn: 1.1, Cu: 1.2 compared to Ag: 2.2, Pb: 3.3, Zn: 2.1, Cu: 4.1 for peat. We show this to be the result of substantial fluvial lithogenic flux of metals (92–97% of total metal flux) to the lake. Total annual metal flux to the lake ranges from: Ag: 4–12 ng/cm2/yr to Zn: 3 383–11 313 ng/cm2/yr. As a result, any contribution of cloud seeding to additional enrichment of Ag in lake sediments is considered negligible. Results show that metal enrichment is not necessarily ubiquitous through a landscape. This has implications for predicting the impacts of atmospheric metal pollution to complex environmental systems.

The distribution and speciation of arsenic (As) were analyzed in individuals of various life stages of a midge, Chironomus riparius, and the mosquito Culex tarsalis exposed to 1000 μg/l arsenate. X-ray absorption spectroscopy (XAS) revealed that C. riparius larvae accumulate As in their midgut, with inorganic arsenate [As(V)] being the predominant form, followed by arsenite [As(III)] and an As-thiol. Reduced concentrations of As in pupal and adult stages of C. riparius indicate excretion of As between the larval and pupal stages. In adults, As was limited to the thorax, and the predominant form was an As-thiol. In Cx. tarsalis, As was not found in high enough concentrations to determine As speciation, but the element was distributed throughout the larva. In adults, As was concentrated in the thorax and eyes of adults. These results have implications for understanding the biotransformation of As and its movement from aquatic to terrestrial environments.

The TRAMO/SEATS program, combined with the Hodrick–Prescott (HP) filter, was used to detect trends and potential change points in time series of dissolved inorganic nitrogen (DIN) at three stations along the Yangtze River. The trend components were extracted, and two change points were successfully detected. The components revealed that DIN has been increasing at all the stations since the 1990s, although variations exist. Changes visible before 2002 illustrate the differences in agriculture development among regions upstream from the stations. The Three-Gorges Dam (TGD), which began to impound in 2003, led to years of different trends. The DIN concentration, which had been trending upward prior to that date, began a slightly downward trend because of NH4+ depletion. Readings at the Yichang station revealed this trend most strongly; those at the Hankou station less so. The Datong station was far enough away from the TGD so that no obvious effects were seen.

Traditional methods of exposure assessment in epidemiological studies often fail to integrate important information on activity patterns, which may lead to bias, loss of statistical power, or both in health effects estimates. Novel sensing technologies integrated with mobile phones offer potential to reduce exposure measurement error. We sought to demonstrate the usability and relevance of the CalFit smartphone technology to track person-level time, geographic location, and physical activity patterns for improved air pollution exposure assessment. We deployed CalFit-equipped smartphones in a free-living population of 36 subjects in Barcelona, Spain. Information obtained on physical activity and geographic location was linked to space-time air pollution mapping. We found that information from CalFit could substantially alter exposure estimates. For instance, on average travel activities accounted for 6% of people's time and 24% of their daily inhaled NO2. Due to the large number of mobile phone users, this technology potentially provides an unobtrusive means of enhancing epidemiologic exposure data at low cost.

Hydrolytic and photolytic degradation were investigated for the ionophore antibiotics lasalocid, monensin, salinomycin, and narasin. The hydrolysis study was carried out by dissolving the ionophores in solutions of pH 4, 7, and 9, followed by incubation at three temperatures of 6, 22, and 28 °C for maximum 34 days. Using LC–MS/MS for chemical analysis, lasalocid was not found to hydrolyse in any of the tested environments. Monensin, salinomycin, and narasin were all stable in neutral or alkaline solution but hydrolysed in the solution with a pH of 4. Half-lives at 25 °C were calculated to be 13, 0.6, and 0.7 days for monensin, salinomycin, and narasin, respectively.Absorbance spectra from each compound indicated that only lasalocid is degraded by photolysis (half-life below 1 h) due to an absorbance maximum around 303 nm, and monensin, salinomycin, and narasin are resistant to direct photolysis because they absorb light of environmentally irrelevant wavelengths.