Soil is an important reservoir of PCDD/PCDF, which can be released when environmental conditions change. Fire is an extreme event that can increase the surface temperatures of soil substantially, yet little is known of the role soil plays in the emission of PCDD/PCDF. Soil containing native PCDD/PCDF was fortified with a mixture of mass labelled PCDD/PCDF and heated between 150°C and 400°C. Both native and mass labelled PCDD/PCDF were released from the soil beyond 200°C. Release of the mass labelled compounds was linearly related to temperature with up to 9 % found in the air stream at 400°C. The release of some native PCDD/PCDF was much greater. At 400°C, emission of 1,2,3,7,8-Cl₅DD was 300% compared to pre-experimental soil. Emission of PCDD/PCDF from soil during bushfires is a relevant process and may originate from both volatilization and formation via de novo or precursor pathways, or dechlorination.

Stomatal ozone flux and flux–response relationships were derived for winter wheat (Triticum aestivum L.) grown under fully open-air ozone fumigation. A stomatal conductance (gₛₜₒ) model developed for wheat in Europe was re-parameterized. Compared to European model parameterizations, the main changes were that the VPD and radiation response functions were made less and more restrictive, respectively, and that the temperature function was omitted. The re-parameterized gₛₜₒ model performed well with an r² value of 0.76. The slope and intercept of the regression between observed and predicted gₛₜₒ were not significantly different from 1 to 0, respectively. An ozone uptake threshold of 12 nmol m⁻² s⁻¹ was judged most reasonable for the wheat flux–response relationship in subtropical China. Judging from both flux- and concentration-based relationships, the cultivars investigated seem to be more sensitive to ozone than European cultivars. The new flux–response relationship can be applied to ozone risk assessment in subtropical regions.

Triclosan (5-Chloro-2-(2,4-dichlorophenoxy) phenol) is an antibacterial compound widely employed in pharmaceuticals and personal care products. Although this emerging compound has been detected in aquatic environments, scarce information is found on the effects of Triclosan to marine organisms. The aim of this study was to evaluate the toxicity of a concentration range of Triclosan through fertilization assay (reproductive success), embryo-larval development assay (early life stage) and physiological stress (Neutral Red Retention Time assay - NRRT) (adult stage) in the marine sentinel organism Perna perna. The mean inhibition concentrations for fertilization (IC₅₀ = 0.490 mg L⁻¹) and embryo-larval development (IC₅₀ = 0.135 mg L⁻¹) tests were above environmental relevant concentrations (ng L⁻¹) given by previous studies. Differently, significant reduction on NRRT results was found at 12 ng L⁻¹, demonstrating the current risk of the continuous introduction of Triclosan into aquatic environments, and the need of ecotoxicological studies oriented by the mechanism of action of the compound.

Lead contamination of urban residential soils is a public health concern. Consequently, there is a need to delineate hotspots in the landscape to identify risk and facilitate remediation. Land use is a good predictor of some environmental pollutants. However, in the case of soil lead, research has shown that land use is not a useful proxy. We hypothesize that soil lead is related to both individual landscape features at the parcel scale and the landscape context in which parcels are embedded. We sampled soil lead on 61 residential parcels in Baltimore, Maryland using field-portable x-ray fluorescence. Thirty percent of parcels had average lead concentrations that exceeded the USEPA limit of 400 ppm and 53% had at least one reading that exceeded 400 ppm. Results indicate that soil lead is strongly associated with housing age, distance to roadways, and on a parcel scale, distance to built structures.

Molecular weight (MW) is a fundamental property of dissolved organic matter (DOM), which potentially affects the binding behavior between DOM and metals. Here, a combined approach of ultrafiltration fractionation, fluorescence excitation-emission matrix quenching and parallel factor analysis (PARAFAC) was employed to elucidate fluorescent characteristics and metal binding properties of individual MW fractions of DOM in landfill leachate. Four humic-like and two protein-like components were identified by PARAFAC. Among them, a fulvic acid-like component was found to be responsible for Cd(II) binding while Cu(II) inclined to complex with humic-like components rather than protein-like ones. Apart from that, MW was found to exert less influence on metal binding than that of specific metals or components. Key components distributed within various fractions of DOM were the main influence on the impact of MW on metal binding.

Biochemical and organismal indices of metal tolerance were studied in Spodoptera exigua exposed to a cadmium-contaminated diet for one or many (33 or 61) generations. Reduced and oxidised glutathione, protein thiols, total anti-oxidant capacity level, glutathione transferase activity, and Cd accumulation were assayed in the haemolymph of the last instar larvae. The cadmium concentration in the whole larval body as well as larval survival, larval duration time and last instar body weight were also measured. Elevated cadmium concentration in the whole body, higher mortality and longer duration of the larval stage in one-generation exposed insects in comparison with those exposed for many generations suggest that metal tolerance builds over time. For the larvae from multigeneration metal treatment, the higher cadmium concentration in larval haemolymph positively correlated with glutathione oxidation and total anti-oxidant capacity. One-generation exposed insects had lower metal concentration in haemolymph than did 33-generation exposed insects.

Liver samples from 53 Franciscana dolphins along the Brazilian coast were analyzed for organobrominated compounds. Target substances included the following anthropogenic pollutants: polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), decabromodiphenylethane (DBDPE), as well as the naturally-generated methoxylated-PBDEs (MeO-PBDEs). PBDE concentrations ranged from 6 to 1797 ng/g lw (mean 166 ± 298 ng/g lw) and were similar to those observed in cetaceans from Northern Hemisphere. PBBs were found in all sampling locations (<LOQ to 57 ng/g lw). DBDPE was detected in 42% of the dolphins from the most industrialized Brazilian state and the concentrations ranging from <LOQ to 352 ng/g lw. Franciscana dolphins from the tropical Brazilian shore presented the highest MeO-PBDE concentrations ever reported for coastal cetaceans (up to 14 μg/g lw). Eight MeO-PBDE congeners were detected and the present investigation constituted the first record of occurrence of six of them in marine mammal livers.

We investigated the effect of increasing CO₂ concentrations on the growth and viability of ecophysiologically different microorganisms to obtain information for a leakage scenario of CO₂ into shallow aquifers related to the capture and storage of CO₂ in deep geological sections. CO₂ concentrations in the gas phase varied between atmospheric conditions and 80% CO₂ for the aerobic strains Pseudomonas putida F1 and Bacillus subtilis 168 and up to 100% CO₂ for the anaerobic strains Thauera aromatica K172 and Desulfovibrio vulgaris Hildenborough. Increased CO₂ concentrations caused prolonged lag-phases, and reduced growth rates and cell yields; the extent of this effect was proportional to the CO₂ concentration. Additional experiments with increasing CO₂ concentrations and increasing pressure (1–5000 kPa) simulated situations occurring in deep CO₂ storage sites. Living cell numbers decreased significantly within 24 h at pressures ≥1000 kPa, demonstrating a severe lethal effect for the combination of high pressure and CO₂.

In recent years the pollution of indoor air with ultrafine particles has been an object of intensive research. Several studies have concurred in demonstrating that outdoor air makes only a limited contribution to polluting indoor air with ultrafine particles, provided significant sources in the immediate neighborhood are absent. Nowadays, electrical devices operated in homes and offices are identified as particle emission sources. A comparison of the emission rates can be made by calculating the total number of particles released with respect to the operating time. The identified particles are condensed semi-volatile organic compounds with a low percentage of non-volatile inorganic components. To characterize the indoor exposure to airborne particles, an algorithm has been developed which permits a realistic calculation of the particle intake and deposition in the human respiratory tract from measured size and time resolved particle number concentrations following the model of the International Commission on Radiological Protection.

A marine food web in Bohai Bay, China, was selected to study methylmercury (MeHg) bioaccumulation, and an aquivalence-based mass balance model was established to explore the possibility of predicting the MeHg concentrations and quantifying MeHg bioaccumulation in the food web. Results showed that both total mercury (THg) and MeHg were biomagnified in the food web. The calculated MeHg concentrations in the selected species agreed well with the measured values, which shows the model could be a useful tool in MeHg concentration prediction in food web. Model outputs also showed that metabolism and growth dilution could be the dominant mechanisms for the reduction of MeHg levels in aquatic organisms. With the increase of trophic level, the contribution of food as a MeHg source for organism is increasing, and MeHg from prey was the dominant source.