Background, aim, and scope Due to the active production and transport of crude oil in the Arabian Gulf region, the Arabian Gulf coasts are routinely polluted with oil. Therefore, such coasts have been subject of studies aiming at assessing the roles of indigenous microbial consortia in cleaning these environments. In the present study, epilithic microbial communities along Kuwait coasts were studied for their oil degradation potential. Materials and methods Gravel particles coated with deep green biofilms were collected from four coastal sites in autumn, winter, and spring. Phototrophs in these consortia were determined in terms of their chlorophyll a contents and identified by their morphological characteristics. Total bacteria were counted microscopically and cultivable bacteria by the dilution plating method on nutrient agar as well as on inorganic medium containing oil as a sole source of carbon and energy. The bacterial community structures were also characterized and compared by denaturing gradient gel electrophoresis (DGGE). Results Epilithic biomass samples from the four sites in the three seasons were rich in diatoms and picocyanobacteria as well as total bacteria. Direct counting gave bacterial numbers per square centimeter gravel surface of 2 to 6 × 10⁷ cells depending on the sampling site and season. Cultivable bacterial numbers on nutrient agar and crude oil as a sole source of carbon were 3 × 10³ to 8 × 10⁴ and 1 × 10³ to 7 × 10³ cells/cm² gravel surface, respectively. The DGGE profiles of epilithon biomass samples revealed major 16S rDNA bands that matched bands of pure oil-utilizing bacterial isolates. Discussion The microbial communities showed a degree of consistency in all sites and seasons. Conclusions The microbial consortia coating gravel particles are potentially suitable tools for self-cleaning of oily Gulf coasts. They are rich in oil-utilizing bacteria whose activities are probably enhanced by oxygen produced by the phototrophic partners in the consortia. Recommendations and perspectives The combination of conventional microbiological analysis with molecular approaches gives an enhanced idea about natural microbial communities especially those with environmental application potential.

Background, aim, and scope Aquatic microcontaminants (MCs) comprise diverse chemical classes, such as pesticides, biocides, pharmaceuticals, consumer products, and industrial chemicals. For water pollution control and the evaluation of water protection measures, it is crucial to screen for MCs. However, the selection and prioritization of which MCs to screen for is rather difficult and complex. Existing methods usually are strongly limited because of a lack of screening regulations or unavailability of required data. Method and models Here, we present a simple exposure-based methodology that provides a systematic overview of a broad range of MCs according to their potential to occur in the water phase of surface waters. The method requires input of publicly available data only. Missing data are estimated with quantitative structure-property relationships. The presented substance categorization methodology is based on the chemicals' distribution behavior between different environmental media, degradation data, and input dynamics. Results Seven different exposure categories are distinguished based on different compound properties and input dynamics. Ranking the defined exposure categories based on a chemical's potential to occur in the water phase of surface waters, exposure categories I and II contain chemicals with a very high potential, categories III and IV contain chemicals with a high potential, and categories V and VI contain chemicals with a moderate to low potential. Chemicals in category VII are not evaluated because of a lack of data. We illustrate and evaluate the methodology on the example of MCs in Swiss surface waters. Furthermore, a categorized list containing potentially water-relevant chemicals is provided. Discussion Chemicals of categories I and III continuously enter surface waters and are thus likely to show relatively steady concentrations. Therefore, they are best suited for water monitoring programs requiring a relatively low sampling effort. Chemicals in categories II and IV have complex input dynamics. They are consequently more difficult to monitor. However, they should be considered if an overall picture is needed that includes contaminants from diffuse sources. Conclusions The presented methodology supports compound selection for (a) water quality guidance, (b) monitoring programs, and (c) further research on the chemical's ecotoxicology. The results from the developed categorization procedure are supported by data on consumption and observed concentrations in Swiss surface waters. The presented methodology is a tool to preselect potential hazardous substances based on exposure-based criteria for policy guidance and monitoring programs and a first important step for a detailed risk assessment for potential microcontaminants.

Background, aim, and scope For many years, highly concentrated wastewater generated from the pulp and paper industry has become the focus of much concern worldwide. The objectives of this study were to determine the treatment efficiency of the alkaline peroxide mechanical pulp (APMP) process wastewater using a sequencing batch reactor (SBR) and analyze the microbial dynamics of the wastewater treatment system using the random amplified polymorphic DNA (RAPD) method. Materials and methods An SBR was applied to the treatment of APMP pulp and paper process wastewater. The wastewater characteristics and many physicochemical operator indicators in the wastewater treatment process were analyzed and determined according to standard methods. Microbial 16 S rDNA in active sludge was extracted, amplified, and analyzed using the RAPD method for the microbial dynamics of the wastewater treatment system. Results and discussion Ten kinds of natural organic compounds of plants such as monoterpene were detected in the APMP pulp and paper process wastewater. With an influent chemical oxygen demand (COD) that varied in the range of 685.7 to 907.5 mg/L, the corresponding effluent COD was 176.5 to 266.1 mg/L and the removal efficiency was 70.3% to 79.8%. An optimal strain (S308: CAGGGGTGGA) was selected to study the population dynamics and diversity of the bacterial community. The RAPD-polymerase chain reaction (PCR) fingerprints showed very high polymorphism of the genetic bands (78-100%). Four groups of species were clustered using the unweighted pair group method with arithmetic (UPGMA) analysis, and the genetic distance was close between the species within each group. The Shannon-Weaver index was high and varied over time with the COD removal. Conclusions The RAPD-PCR technique can be used to study microbial dynamics, which was shown to vary over time with the removal efficiency of SBR treating APMP pulp and paper process wastewater.

Background, aim and scope Polychlorinated biphenyls (PCB) and dichlorodiphenyltrichloroethane (DDT) concentrations were determined in the liver of two deep sea fish species, Mediterranean slimehead and blackfin sorcerer, from the Adriatic Sea (southeastern Mediterranean Sea). Results and discussion The examination of congener profiles showed that hexachlorinated molecules were dominant (hexa-CBs, 55.3-56.2%), followed by penta-CBs (21.5-21.8%) and hepta-PCB 180 (14.9-16.0%). PCB 138, 153 and 180 were the prominent congeners accounting for 69.3% of the total PCBs. Among the compounds of DDT, p,p′-DDE was the most dominant molecule (Mediterranean slimehead, 86.6%; blackfin sorcerer, 92.8%), demonstrating the old age of these compounds in the environment. In both species, PCB contents were higher than those of DDTs. Contaminant load was higher in Mediterranean slimehead (PCBs, 1,086 ng g⁻¹ lipid weight; DDTs, 799 ng g⁻¹ lipid weight) than in blackfin sorcerer (PCBs, 561 ng g⁻¹ lipid weight; DDTs, 224 ng g⁻¹ lipid weight). Conclusion The high ratios ΣPCBs/ΣDDTs indicated predominantly industrial versus agrarian activities in the area. Dioxins toxic equivalent (TEQ) concentrations (8.1-18.7 pg TEQ per gram wet weight) reached those encountered in marine organisms at higher levels in the trophic chain, revealing the onerous status of contamination by PCBs in Mediterranean deep sea biota.

Background and purpose In Pakistan, almost 70% of the population lives in rural areas. Ninety-four percent of households in rural areas and 58% in urban areas depend on biomass fuels (wood, dung, and agricultural waste). These solid fuels have poor combustion efficiency. Due to incomplete combustion of the biomass fuels, the resulting smoke contains a range of health-deteriorating substances that, at varying concentrations, can pose a serious threat to human health. Indoor air pollution accounts for 28,000 deaths a year and 40 million cases of acute respiratory illness. It places a significant economic burden on Pakistan with an annual cost of 1% of GDP. Despite the mounting evidence of an association between indoor air pollution and ill health, policy makers have paid little attention to it. This review analyzes the existing information on levels of indoor air pollution in Pakistan and suggests suitable intervention methods. Methods This review is focused on studies of indoor air pollution, due to biomass fuels, in Pakistan published in both scientific journals and by the Government and international organizations. In addition, the importance of environmental tobacco smoke as an indoor pollutant is highlighted. Results Unlike many other developing countries, there are no long-term studies on the levels of indoor air pollution. The limited studies that have been undertaken indicate that indoor air pollution should be a public health concern. High levels of particulate matter and carbon monoxide have been reported, and generally, women and children are subject to the maximum exposure. There have been a few interventions, with improved stoves, in some areas since 1990. However, the effectiveness of these interventions has not been fully evaluated. Conclusion Indoor air pollution has a significant impact on the health of the population in Pakistan. The use of biomass fuel as an energy source is the biggest contributor to poor indoor air quality followed by smoking. In order to arrest the increasing levels of indoor pollution, there is a dire need to recognize it as a major health hazard and formulate a national policy to combat it. An integrated effort, with involvement of all stakeholders, could yield promising results. A countrywide public awareness campaign, on the association of indoor air pollution with ill health, followed by practical intervention would be an appropriate approach. Due to the current socioeconomic conditions in the country, development and adoption of improved cooking stoves for the population at large would be the most suitable choice. However, the potential of biogas as a fuel should be explored further, and modern fuels (natural gas and LPG) need to be accessible and economical. Smoking in closed public spaces should be banned, and knowledge of the effect of smoking on indoor air quality needs to be quantified.

With the aim of developing new uses of sewage sludge, a byproduct of municipal wastewater treatment plants, in the present work the calcination at 900° C of this waste with or without CaCO3 added was performed; the sludge was obtained from a local municipal wastewater treatment plant. The purpose was to study the ability of the CaCO3 to capture SO 2 during the incineration. The resulting ashes were reactivated at different experimental conditions to obtain desulfurant sorbents to be used in a further desulfurization process at low tempreature. The humidity, total solids and fixed and volatile solids were determined in the sludge with and without CaCO3 added. The elementary analysis of the dry sludge and of the calcinated was obtained. Results show that the C percentage highly decreases in the incineration due to the release of the volatile carbon compounds. The sulphur percentage increases principally due to the release of the volatile matter. The resulting ashes with or without CaCO3 added were studied by Thermogravimetry. T.G. curves show that not all the CaCO3 was calcinated mainly when the amout of CaCO3 added was high. The specific surface area of the dry sludge, of the ashes and of the sorbents prepared by reacitivation of the ashes was also determined | We are thankful to MICINN for financial support of this work under Porject MAT 2009-10727

International audience | Can the existence and the density of particular plant species give several informations about the degree of soil pollution? After having chosen different sites for this survey, the identification of collected plant species and the soil characteristics of collection sites were compared and some correlations were established. Data on growth of collected plants indicated the existence of two ecotypes of Thlaspi caerulescens. It has been shown the preference of one of the ecotypes for the metal-contaminated soils. | La présence et l'abondance de certaines espèces végétales peuvent-elles donner des informations sur l'état de pollution d'un sol ? Après avoir choisi des sites d'étude, y avoir caractérisé des peuplements végétaux et la pollution du sol pour établir des corrélations, une mise en culture des plantes a permis de mettre en évidence deux écotypes de Thlaspi caerulescens et une préférence de l'un des deux pour les sols pollués. Mots-clés Pollutions minières, métaux lourds, bioindicateur, Thlaspi caerulescens, phytostabilisation.