Most of urban air quality studies focus on the megacities of North America, Europe and, recently, Asia. Meanwhile, the most polluted urban areas in the world are rapidly growing large, mid-size and small cities of Asia, Middle East, Africa and South America. This raises a question: why relatively smaller cities are more polluted than the megacities? This study presents the first comprehensive decade-long analysis of the effects of fuel and transport regulations on PM2.5 (particulate matter of aerodynamic diameter <2.5 μm) pollution in Quito, a medium-size city of South America. The effectiveness of a number of regulations is quantified through the elaboration of a high accuracy (98%) regression model. The model estimated that the PM2.5 concentrations were reduced by 67.6 μg/m3, combating the effect of city growth and intense motorization, reducing the annual PM2.5 concentrations to 17.4 μg/m3. This study is recommended as a guideline for thousands of other cities worldwide looking for optimal urban particulate pollution management.

Liver tumours in flatfish have been diagnosed using histopathology for decades to monitor the impacts of marine pollution. Here we describe the application of specific gene (retinoblastoma, Rb) profiling in laser capture micro-dissected samples, and a suppression subtractive hybridization (SSH) approach to isolate differentially expressed genes in hepatocellular adenoma (HCA) samples from dab, Limanda limanda.The Rb profiles from apparently normal and HCA micro-dissected samples of fish from the North Sea showed no significant difference, and genotypic heterogeneity within defined histological phenotypes was observed. In the SSH, sequences associated with cell signalling, cell cycle, gene expression regulation, protein transport and protein degradation were isolated. These included up-regulation of arrestin domain containing 3 (arrdc3), Rac-1 and tribbles, and down-regulation of ankyrin repeat/sterile alpha-motif domain-containing protein 1B-like (ANKS1B-like), c-fos, CDKN1B and RhoA-like sequences, previously implicated in mammalian HCA. This study offers new candidates involved in fish liver tumour development.

Yellow River delta (YRD) is a typical example of a valuable coastal ecosystem that is under increasing anthropogenic threat in China. To understand the current health status of this region, three surveys in 2011 for the abiotic conditions and macrobenthic assemblages were performed. The concentration of trace metals were relatively low in the sediment at all sampling stations representing a good sediment quality. A total of 159 macrobenthic species were identified during the three surveys. ABC curves showed that the macrobenthic fauna at 8 sampling stations suffered disturbances from human activities. M-AMBI index indicates that the benthic ecological quality of YRD is currently still not in a good condition. Five trace metals, water temperature and depth were the main environmental variables affecting the distribution pattern of macrobenthic assemblages. Community succession has occurred over the past 60years, as evidenced by changes of species composition, key species, distribution pattern and range.

In this study, the long-term trend in atmospheric carbon monoxide (CO) concentration was analyzed using the CO levels measured (intermittently) at an air quality monitoring (AQM) station in Seoul, Korea, between the years 1987 and 2013. Temporal trends in CO were analyzed on an annual and seasonal basis in reference to other important air pollutants such as methane (CH4), particulate matter (PM10), sulfur dioxide (SO2), nitrogen monoxide (NO), nitrogen dioxide (NO2), mercury (Hg), and ozone (O3). The annual mean of CO for the entire period was 0.93 ± 0.22 ppm. CO levels were reduced by 83% from 3.25 ± 0.78 ppm (1987) to 0.51 ± 0.31 ppm (2013). Its relative reduction was compared over three periods chosen arbitrarily as period 1 (fast reduction, 1987–1988), period 2 (intermediate reduction, 1999–2000), and period 3 (slow reduction, 2004–2013). The concentrations of CO were strongly correlated with others (e.g., SO2, NO, NO2, O3, and Hg), suggesting the effects of similar source processes (e.g., fuel combustion). The reduction in its level was marginally consistent with the decreasing trend in the total CO column concentration in Seoul by the Measurements of Pollution in the Troposphere (MOPITT) satellite between 2000 and 2013, indicating decreasing anthropogenic CO emissions (despite increasing anthropogenic CO2 emissions). The rapid relative reduction of CO in period 1 and the subsequent slower but moderate reduction thereafter appear to reflect the effects of both enforcement of administrative regulations and advances in emissions control technologies.

Despite the growing recognition of the importance of water and sediment quality there is still limited information on contamination levels in many regions globally including the Red Sea. This study provides a comprehensive assessment of three classes of contaminants (Polycyclic Aromatic Hydrocarbons - PAH; metals; plastics) in coastal sediments along the Saudi Arabian Red Sea mainly collected using grabs. Background concentrations are provided for metals in the region. Concentrations of metals and PAH were generally low in comparison to international guidelines. A clear relationship between the concentration of metals and anthropogenic sources was not always apparent and dust and vegetation may be relevant players in the region. Microplastic items (mainly polyethylene) were abundant (reaching up to 1gm−2 and 160piecesm−2) and in general associated with areas of high human activity. This study provides critical information for future monitoring and the development of national policies within the Red Sea region.

In this paper three well known Gaussian dispersion models have been evaluated for a case study of a steel plant using complete and incomplete upper air meteorological data.In developing countries, the availability of surface and upper air meteorological data is limited. AMS/EPA Regulatory Model (AERMOD), Advanced Dispersion Modeling System (ADMS) and Industrial Source Complex Model (ISC3) have been evaluated for both real and estimated upper meteorological data and the results have been compared with field measurements both in the horizontal and vertical directions.The results show significant differences in predicted concentrations when modeling with real (actual) and estimated upper meteorological data. The differences ranged from 100% to 450%. Comparison of model performance suggests that AERMOD and ADMS with real meteorological data produce consistent results in the horizontal direction while ISC3 output over-predicts in general. In AERMOD and ISC3 the predicted concentrations have a similar trend of variation in the vertical direction but in ADMS the concentration variation in the vertical direction exhibited different trends. In general, the ADMS predicted concentrations under-estimated field observations.The paper suggests that upper data must be used for modeling and the default values must be used with care. In absence of upper meteorological data, users could estimate upper meteorological data by different available algorithm rather than only default option of models.

Pb/Ca profiles were measured on ten live collected Ostrea edulis from three sites characterized by different levels of lead content. Intra-shell and inter-shell reproducibility were tested comparing several Pb/Ca profiles measured by LA-ICP-MS within a specimen, and within specimens from the same site. Results indicate that signals recorded are reproducible and mean shell Pb/Ca values are site-dependent. Second order variability is explained either by smoothing effects, biological effects or micro-environmental heterogeneities in lead distribution. Mean Pb contents measured in marine bivalve shells are reviewed here. Ranging from 0 to 50ppm, they show a strong relationship with the environmental level of local lead contamination, and do not appear species-dependent. Our measurements show a linear relationship between mean shell Pb/Ca and surface sediment Pb concentrations, making marine bivalves and particularly O. edulis a potential accurate bio-monitoring tool able to monitor bioavailable lead along European coasts since Mesolithic, with an annual resolution.

Canadian Arctic and Subarctic regions experience a rapid decrease of sea ice accompanied with increasing shipping traffic. The resulting time-space changes in shipping noise are studied for four key regions of this pristine environment, for 2013 traffic conditions and a hypothetical tenfold traffic increase. A probabilistic modeling and mapping framework, called Ramdam, which integrates the intrinsic variability and uncertainties of shipping noise and its effects on marine habitats, is developed and applied. A substantial transformation of soundscapes is observed in areas where shipping noise changes from present occasional-transient contributor to a dominant noise source. Examination of impacts on low-frequency mammals within ecologically and biologically significant areas reveals that shipping noise has the potential to trigger behavioral responses and masking in the future, although no risk of temporary or permanent hearing threshold shifts is noted. Such probabilistic modeling and mapping is strategic in marine spatial planning of this emerging noise issues.

Phthalates are an emerging class of environmental pollutants whose distribution and effects in aquatic environments are not well characterized. We analyzed intertidal and emerged beach sediments from the Abruzzo coastline, along the Adriatic Sea, finding significant phthalate concentrations in marine sediments. Phthalate baseline levels in the intertidal environment, marked by substantial interplay of sediment, water and air, were determined. We used statistical rank methods to select representative phthalate compositions, for which we derived risk levels for ingestion, dermal absorption and inhalation. Our study shows that phthalates are a major cause of pollution along the Abruzzo coast, with river transport of sediments a continuous source of replenishment. Phthalate concentrations in two specific sites were determined to be of the same order of magnitude as the safety, remediation-warranting, threshold set by Italian law. Phthalates, heavy metals, PAHs appear to be correlated. We discuss possible intervention and mitigation strategies.

Organochlorines were determined in fish and sediment collected from Izmir and Çandarlı Bays. The results indicated that ΣCyclodiens were generally predominant contaminants. In all samples, p,p′-DDE was the predominant DDT congener. Aroclors were found in noticeably higher levels than OCPs in sediment and the highest levels of Aroclors, OCPs were found in Nemrut which can be attributed to industrial activities. According to Sediment Quality Guidelines, DDTs were lower than the values that may cause adverse biological risk in sediment samples. Aroclor 1254 in sediments only exceeded the TEL value at Nemrut site. The maximum values of ΣOCPs were found in fish collected from Gülbahçe, while Aroclors were measured in Aliaga. According to related indices, results indicate no recent influxes of DDT in the sampling areas. The estimated daily intake of DDTs, Aroclor1254 were below the acceptable daily intake level recommended by FAO/WHO.