Polycyclic aromatic hydrocarbon (PAH) extracts of fine particles (PM₂.₅) collected from combustion of seven wood species and briquettes were tested for mutagenic activities using Ames test with Salmonella typhimurium TA98 and TA100. The woods were Pinus pinaster (maritime pine), Eucalyptus globulus (eucalypt), Quercus suber (cork oak), Acacia longifolia (golden wattle), Quercus faginea (Portuguese oak), Olea europea (olive), and Quercus ilex rotundifolia (Holm oak). Burning experiments were done using woodstove and fireplace, hot start and cold start conditions. A mutagenic response was recorded for all species except golden wattle, maritime pine, and briquettes. The mutagenic extracts were not correlated with high emission factors of carcinogenic PAHs. These extracts were obtained both from two burning appliances and start-up conditions. However, fireplace seemed to favour the occurrence of mutagenic emissions. The negative result recorded for golden wattle was interesting, in an ecological point of view, since after confirmation, this invasive species, can be recommended for domestic use.

Fluorotelomer alcohols (FTOHs) and perfluorooctane sulfonamides (FOSAs) are present in consumer products and are semi-volatile precursors of persistent perfluoroalkyl acids (PFAAs). The high variability of levels of FTOHs and FOSAs in products makes it difficult to derive FTOH- and FOSA-emissions from urban areas based on emission factors. Here we used a multimedia mass balance model that describes the day–night cycle of semi-volatile organic chemicals in air to interpret measurements of 8:2 FTOH, 10:2 FTOH, MeFOSA and EtFOSA from a sampling campaign in summer 2010 in Zurich, Switzerland. The estimated emission source strength of the four substances follows the sequence: 8:2 FTOH (2.6 g/h) > 10:2 FTOH (0.75 g/h) > MeFOSA (0.08 g/h) > EtFOSA (0.05 g/h). There is no FTOHs- or FOSAs-related industry in Zurich. Accordingly, our estimates are representative of diffusive emissions during use and disposal of consumer products, and describe noticeable sources of these PFASs to the environment.

A very high ozone episode with observed hourly values above 350 μg m⁻³ occurred in July 2005 at the Lamas d’Olo air quality monitoring station, located in a mountainous area in the north of Portugal. Aiming to identify the origin and formation of this ozone-rich episode, a statistical analysis and a modelling approach were applied. A cross-spectrum analysis in the frequency domain and a synoptic analysis of the meteorological and air quality time series were performed. In order to go further in this analysis, a numerical modelling approach was applied. The results indicate that the transport of ozone and its precursors is the main responsible for the high ozone concentrations. Together with the local mountain breeze and subsidence conditions, the sea-breeze circulation transporting pollutants from the coastal urban and industrialized areas that reach the site during late afternoon turn out to be the driving forces for the ozone peaks.

The close relationship between soil organic matter and the bioavailability of POPs in soils suggests the possibility of using it for the extrapolation between different soils. The aim of this study was to prove that TOC content is not a single factor affecting the bioavailability of POPs and that TOC based extrapolation might be incorrect, especially when comparing natural and artificial soils. Three natural soils with increasing TOC and three artificial soils with TOC comparable to these natural soils were spiked with phenanthrene, pyrene, lindane, p,p′-DDT, and PCB 153 and studied after 0, 14, 28, and 56 days. At each sampling point, total soil concentration and bioaccumulation in earthworms Eisenia fetida were measured. The results showed different behavior and bioavailability of POPs in natural and artificial soils and apparent effects of aging on these differences. Hence, direct TOC based extrapolation between various soils seems to be limited.

In this study on-road gaseous emissions of vehicles are investigated using remote sensing measurements collected over three different periods. The results show that a high percentage of gaseous pollutants were emitted from a small percentage of vehicles. Liquified Petroleum Gas (LPG) vehicles generally have higher gaseous emissions compared to other vehicles, particularly among higher-emitting vehicles. Vehicles with high vehicle specific power (VSP) tend to have lower CO and HC emissions while petrol and LPG vehicles tend to have higher NO emissions when engine load is high. It can be observed that gaseous emission factors of petrol and LPG vehicles increase greatly within 2 years of being introduced to the vehicle fleet, suggesting that engine and catalyst performance deteriorate rapidly. It can be observed that LPG vehicles have higher levels of gaseous emissions than petrol vehicles, suggesting that proper maintenance of LPG vehicles is essential in reducing gaseous emissions from vehicles.

The spatial distribution of per- and polyfluoroalkyl compounds (PFCs) were investigated in coastal waters collected onboard research vessel Snow Dragon from the East to South China Sea in 2010. All samples were prepared by solid-phase extraction and analyzed using high performance liquid chromatography/negative electrospray ionization-tandem mass spectrometry (HPLC/(−)ESI-MS/MS). Concentrations of 9 PFCs, including C₄ and C₈ (PFBS, PFOS) perfluoroalkyl sulfonate (PFSAs), C₅–C₉ and C₁₃ (PFPA, PFHxA, PFHpA, PFOA, PFNA, PFTriDA) perfluoroalkyl carboxylates (PFCAs), and N-ethyl perfluorooctane sulfonamide (EtFOSA) were quantified. The ΣPFC concentrations ranged from 133 pg/L to 3320 pg/L, with PFOA (37.5–1541 pg/L), PFBS (23.0–941 pg/L) and PFHpA (0–422 pg/L) as dominant compounds. Concentrations of PFCs were greater in coastal waters along Shanghai, Ningbo, Taizhou, Xiamen and along coastal cities of the Guangdong province compared to less populated areas along the east Chinese coast. Additionally, the comparison with other seawater PFC measurements showed lower levels in this study.

The CH₄ oxidation dynamics was investigated by observing the CH₄ oxidation rates at concentrations (from 1.0 × 10⁴ ppmv to 2.0 × 10⁵ ppmv) mixed with O₂ (from 5.0 × 10⁴ ppmv to 7.5 × 10⁵ ppmv). The CH₄–O₂ dual-substrate model based on Michaelis–Menten equation ( [Formula: see text] = 1.4 × 10⁵ ppmv; Vₘₐₓ = 7.6 × 10² μmol kg⁻¹ d⁻¹; [Formula: see text] = 5.5 × 10⁴ ppmv) was got and agreed well with the experimental data when the initial O₂/CH₄ ratio reached 3:1, indicating full aerobic CH₄ oxidization. Anoxic CH₄ oxidation gradually became predominant with decreasing O₂/CH₄ ratios. The effect of CH₄ is more significant than O₂, as evidenced by higher slope (0.58 kg⁻¹ d⁻¹) of [Formula: see text] line graph compared with that of [Formula: see text] line graph (0.062 kg⁻¹ d⁻¹). The paper presents the dynamics of CH₄ oxidation and proposes that ratio of O₂/CH₄ need to be considered for their dynamically changing in environmental habitats. The findings provide an important parameter for optimizing the operations of breathing biocover systems.

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.

Hydrochemical sampling of South Pennine (UK) headwater streams draining eroded upland peatlands demonstrates these systems are nitrogen saturated, with significant leaching of dissolved inorganic nitrogen (DIN), particularly ammonium, during both stormflow and baseflow conditions. DIN leaching at sub-catchment scale is controlled by geomorphological context; in catchments with low gully densities ammonium leaching dominates whereas highly gullied catchments leach ammonium and nitrate since lower water tables and increased aeration encourages nitrification. Stormflow flux calculations indicate that: approximately equivalent amounts of nitrate are deposited and exported; ammonium export significantly exceeds atmospheric inputs. This suggests two ammonium sources: high atmospheric loadings; and mineralisation of organic nitrogen stored in peat. Downstream trends indicate rapid transformation of leached ammonium into nitrate. It is important that low-order headwater streams are adequately considered when assessing impacts of atmospheric loads on the hydrochemistry of stream networks, especially with respect to erosion, climate change and reduced precipitation.

Trophic transfer of Hg across lakes within a region has been related to multiple environmental factors, but the nature of these relationships across distinct basins within individual large lakes is unknown. We investigated Hg bioaccumulation in zooplankton in basins of differing trophic status in Lake Champlain (Vermont, USA) to determine the strongest predictors of Hg bioaccumulation. Zooplankton were sampled in Malletts Bay (oligotrophic) and Missisquoi Bay (eutrophic) in 2005–2008. Zooplankton in the eutrophic basin had lower concentrations of total Hg and MeHg than those in the oligotrophic basin in all years but 2007, when no bloom occurred in Missisquoi. In addition, Hg concentrations in seston and small zooplankton, sampled during 2009 at 12 sites spanning the lake, decreased with increasing phytoplankton and zooplankton biomass. Thus, Hg bioaccumulation in zooplankton across basins in Lake Champlain is related to trophic status, as observed previously in multiple lake studies.