The effects of CO2-related acidification on two crustacean populations, the isopod Cyathura carinata and the amphipod Elasmopus rapax, were studied. Three pH levels were tested: artificial seawater without CO2 injection and two levels of reduced pH. Even though RNA:DNA ratio was reduced for both species, no statistical significant differences were found between the control and the treatments. Both species experienced a reduction in survivorship, longevity and the body length of surviving animals; although the impairment observed in E. rapax was more severe than in C. carinata. The long life span isopod and the short life span amphipod experienced a high degree of impairment in the reproduction, likely due to the reallocation of resources from reproduction to body maintenance and increasing survival by postponing the brood production. Regardless of the underlying processes and the energetic pathways, both experienced failure to reproduce, which could lead to the local extinction of these species.

In regions where air quality data are scarce or access thereto is limited, a comprehensive understanding of air pollution is hindered by a lack of emission data and ambient air pollution measurements. Therefore, in this pilot study, we assess the feasibility of estimating particulate matter (PM) mass concentrations from a meteorological index. Measured PM concentrations from air quality monitoring stations (2013–2016) situated in and around South African air pollution priority areas were analysed. Simulated meteorological parameters were used to calculate the newly-developed Air Dispersion Potential (ADP) index, which describes the meteorological potential for pollution dispersion in the atmosphere. For most conditions, there exists weak (r = 0.1–0.29) to moderate (r = 0.30–0.49) correlations between the ADP index and PM classes. At the three stations with adequate data availability, it was found that the ADP index was relatively successful in predicting conditions of high PM concentrations. An investigation of the effect of meteorological conditions on the diurnal variation of PM concentrations led to both the quantification of this effect, and the realization that at these diverse sites, up to 29% of variation in hourly PM concentrations can be explained by variations in meteorology. The application of the index in this way can play an important role in air quality management by quantifying the impacts of meteorological drivers on PM peaks.

The aim of this study was to assess if the epiphyte Tillandsia bergeri is feasible to be used as a biomonitor of pesticides in the air by comparing with the results of the artificial XAD-resin based passive air sampler (XAD-PAS). Biomonitors and XAD-PAS were deployed at 10 sites of Quequén Grande River watershed (Buenos Aires province, Argentina) during three exposure periods. Endosulfan was the main pesticide found in T. bergeri as well as in XAD-PAS, even after the ban was in effect. Higher endosulfan levels were observed during pesticide application period in XAD-PAS, while T. bergeri showed a decreasing trend during this period. Chlorpyrifos concentrations were in the same order than endosulfan in XAD-PAS, while T. bergeri showed significantly lower levels. Concentrations of legacy pesticides (hexachlorocyclohexanes, chlordanes, dieldrin, heptachlors) registered a low contribution to total pesticides analyzed both in T. bergeri and XAD-PAS, reflecting the past use of organochlorine pesticides in the region. Trifluralin showed the lowest concentrations in T. bergeri while XAD-PAS exhibited a higher proportion in some sites. Even both samplers showed that endosulfan was the most frequent pesticide found, environmental processes such as volatilization and photodegradation, as well as biological processes in T. bergeri have probably occurred and therefore pesticides accumulation was altered. Results demonstrate the importance of taking into account the type of sampling media when analyzing atmospheric pesticide composition. Nevertheless, the use of T. bergeri and XAD-PAS allowed discriminating efficiently the relative contribution of currently used pesticides versus legacy pesticides to air pollution.

The air-water exchange of polycyclic aromatic hydrocarbons (PAHs) is an important process in determining the fate, transport and chemical loadings of these contaminants in the atmosphere and water bodies. Concentration levels of PAHs in air (gaseous and particulate) and surface water were investigated in the environments of two polluted lagoons along the eastern coast of the Red Sea to study air water exchange and dry deposition fluxes. Nine priority parent PAHs and nine methylated PAHs were identified and quantified by GC-MS. The range of total PAHs in surface water was from 120.29 ng L⁻¹ to 524.45 ng L⁻¹ (average: 308.7 ng L⁻¹, n = 19). The PAHs levels in air recorded significant rise form the previous study. The probable sources of dissolved PAHs in water were found predominantly to be of petrogenic origin in one lagoon and of pyrogenic origin in the other lagoon. The dry deposition fluxes for individual congeners ranged between 0.01 ng m⁻²d⁻¹ to 2.82 μg m⁻²d⁻¹. After Henry's law constant corrections for temperature and salinity; the air-water exchange fluxes were found in the range of −9.7 × 10⁴ to 8.6 × 10⁶ ngm⁻²d⁻¹ with an average of 6.8 × 10⁵ ngm⁻²d⁻¹. Beside the other sources of PAHs in the studied lagoons, high temperature and wastewater dumping might affect the magnitude and direction of air-water exchange fluxes.

Speciated VOCs and regulated air pollutant emissions (CO, HC and NO) of carburetor (CB) and fuel injection (FI) motorcycles were evaluated based on engine dynamometer tests. Effects of engine loads and emission control systems were evaluated. CB was equipped with oxidation catalytic converter (OCC) and secondary air system (SAS) while FI had three-way catalytic converter (TWC) and oxygen sensor (OS). Under normal operation of the control devices, the emissions of regulated pollutants and the sum of detected VOCs (ΣVOC) were higher in CB than in FI motorcycle. Alkanes and aromatics had the highest concentrations contributing approximately 90% to the ΣVOC while xylene and toluene were most abundant among the BTEX, in both motorcycles. Emissions of all regulated pollutants and ΣVOC increased with increase in engine load. The emission control devices showed differential efficiencies on different VOC groups. Average emission reduction efficiencies of OCC with SAS (CB motorcycle) were 45.4% (ΣVOC) and 48.6% (BTEX) and TWC with OS (FI motorcycle) were 74.4% (ΣVOC) and 88.0% (BTEX). Without SAS, the efficiency of OCC dropped to 30.2% (ΣVOC) and 34.9% (BTEX) in CB motorcycle. Similarly, the efficiency of TWC reduced to 69.0% (ΣVOC) and 85.2% (BTEX) when the OS was blocked in FI motorcycle. The ozone formation potentials of VOCs ranged from 500 mg-O3/m3 (FI motorcycle with TWC and OS, TO 20%) to 2218 mg-O3/m3 (CB motorcycle without control system, TO 30%).

Mercury is considered a ubiquitous, toxic, and global pollutant. In this study, ambient Total Gaseous Mercury (TGM) concentrations over the South African Highveld are characterised. Studies on ambient mercury in this region is important because of various anthropogenic emission sources. In this pilot study, concentrations of TGM and criteria pollutants (O3, SO2, NO, NO2, and CO) were measured concurrently with meteorological parameters at Balfour (BF), Middelburg (MB), and Standerton (ST) from January 2009 to December 2009. The spatial variation of TGM concentrations ranged from 0.40 to 28.72 ng/m3 (1.99 0.94 ng/m3), 0.12–9.91 ng/m3 (1.04 0.62 ng/m3), and 0.21–32.10 ng/m3 (1.25 1.38 ng/m3), at BF, MB, and ST, respectively. Generally, concentrations fell within the Northern Hemisphere background range of 1.5–1.7 ng/m3 and Cape Point, South Africa background of 1.2–1.4 ng/m3, with the exception of outliers. The outliers were much higher than the background values and may be the result of pollution events. Seasonal variation varied with descending orders of summer, spring, winter, autumn, at BF; summer, winter, autumn, spring at MB; and winter, spring, summer at ST (no data available for autumn). This study observed no profound diurnal patterns at BF and MB where sparse local and regional sources appear to have been the predominant sources. An interesting phenomena, however, was observed at ST where the diurnal cycle suggests a potential significant influence from local domestic combustion sources.

The air quality is an increasingly concerning topic. Efficient air quality monitoring system is highly required in urban areas due to the existing different types of air pollution sources. Consequently, air pollution profiles of the monitored region should be regularly evaluated to infer the efficiency of the monitoring system. This study applied principal components analysis (PCA) to air quality data from Porto (Portugal), aiming to characterize the spatial distribution of NO₂, O₃ and PM₁₀ concentration profiles. In the analysed period (2006 and 2013), some of the selected monitoring sites have been closed and others were moved to other locations. PCA allowed the evaluation of these changes in geographical distribution of the monitoring sites and the definition of proposals to improve the efficiency of air quality monitoring system. The performed analysis concluded that these last changes were correctly performed, but the reduction of the monitoring sites for NO₂ and O₃is still possible, being optimized the current number for PM₁₀. In addition, the application of computational model HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) allowed analysing the air pollution transport over long distances in high pollutant concentration episodes, having found that the variation of NO₂ and O₃ concentrations may be strongly influenced by air masses from the north of Spain. For PM₁₀, there are two different air mass trajectories: the transport of air masses from the Galicia region and from North Africa.

Abstract: The cryosphere in South America is a very important resource because it is the main source of water for 85 million inhabitants distributed in Colombia, Ecuador, Peru, Bolivia, Chile and Argentina [1-2]. To know the effects due to global phenomena such as arctic oscillation (AO) in the reduction of the cryosphere in this region, we proceeded to analyze sources of reanalysis information (ERA-40; NCEP/NCAR Reanalysis) and high resolution snow cover (MOD10 500m) from Moderate-Resolution Imaging Spectroradiometer (MODIS). Several linear adjustments were made to observe how snow cover variations (Y) responded to variations in AO (X1 ), surface temperature (X2 ) and snow precipitation (X3 ).

Exposure to polycyclic aromatic hydrocarbons (PAHs) during pregnancy may pose adverse health risk to both the mothers and babies. In the present study, 188 pregnant women of different trimesters were recruited in Guangzhou, south China, and nine hydroxyl PAHs (OH-PAHs) and a biomarker of DNA oxidative damage, 8-hydroxy-2′-deoxyguanosine (8-OHdG), were determined in their urine samples. All OH-PAHs except for 4-hydroxyphenanthrene and 6-hydroxychrysene were found in > 90% samples, with total concentration in the range of 0.52 to 42.9 μg/g creatinine. In general, concentration levels of OH-PAHs in pregnant women were lower than those in general population in the same research area but with higher levels in working women than in housewives. The mean daily intakes of PAHs from dietary estimated by urinary OH-PAHs were 0.021, 0.004, 0.047, and 0.030 μg/kg_bw/day for naphthalene, fluorene, phenanthrene, and pyrene, respectively, which were much lower than the reference doses (20, 30, and 40 μg/kg_bw/day for naphthalene, pyrene, and fluorene, respectively) derived from chronic oral exposure data by the United States Environmental Protection Agency. The low exposure levels of PAHs may be attributed to the traditional dietary taboo of Chinese pregnant women, which is to minimize the consumption of “toxic” food. The concentrations of 8-OHdG (4.67–49.4 μg/g creatinine) were significantly positively correlated with concentrations of several OH-PAHs, such as metabolites of naphthalene, fluorene, and phenanthrene (r = 0.3–0.6). In addition, the concentrations of 8-OHdG were higher in working women than in housewives when exposed to the same levels of PAHs, partly indicating the possible relation between work-related pressure for working women and the oxidative stress.