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Antibiotic resistance is considered a universal health threat of the 21st century which its distribution and even development are mainly mediated by water-based media. Disinfection processes with the conventional methods are still the most promising options to combat such crises in aqueous matrices especially wastewater. Knowing that the extent of effectiveness and quality of disinfection is of great importance, this paper aimed to systematically review and discuss ozonation (as one of the main disinfectants with large scale application) effect on removing antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) from aqueous solutions, for which no study has been reported. For this, a comprehensive literature survey was performed within the international databases using appropriate keywords which yielded several studies involving different aspects and the effectiveness extent of ozonation on ARB & ARGs. The results showed that no definite conclusion could be drawn about the superiority of ozone alone or in a hybrid form. Mechanism of action was carefully evaluated and discussed although it is still poorly understood. Evaluation of the studies from denaturation and repairment perspectives showed that regrowth cannot be avoided after ozonation, especially for some ARB & ARGs variants. In addition, the comparison of the effectiveness on ARB & ARGs showed that ozonation is more effective for resistant bacteria than their respective genes. The degradation efficiency was found to be mainly influenced by operational parameters of CT (i.e. ozone dose & contact time), solids, alkalinity, pH, and type of pathogens and genes. Moreover, the correlation between ARB & ARGs removal and stressors (such as antibiotic residuals, heavy metals, aromatic matters, microcystins, opportunistic pathogens, etc.) has been reviewed to give the optimal references for further in-depth studies. The future perspectives have also been reported.

Contaminant removal from wastewater using natural biosorbents has been widely studied as a suitable and environmentally benign alternative for conventional techniques. Currently, researchers are working on various biomass-based composites for wastewater remediation to improve the performance of natural biosorbents. This review takes into focus a wide range of biomass-based composites like hydrogel composites, metal oxide composites, magnetic composites, polymer composites, carbon nanotubes (CNTs) and graphene composites, metal organic framework composites (MOFs) and clay composites for the removal of various contaminants from wastewater. It is evident from the literature survey that the composite fabrication involves the modification of morphological and textural features of the biomass which results in significant enhancement of adsorption capacity. Apart from this, regeneration of the used biomass-based composite is also studied in depth in order to overcome the problem of solid waste generation. This review would prove to be beneficial for researchers who are currently focusing on the development of cost-effective, easily available, recyclable biomass-based composites with enhanced adsorption capacities for wastewater treatment.

By means of a literature survey, earthworm species of significant relevance for soil functions in different biogeographical regions of Europe (Atlantic, Boreal, Mediterranean) were identified. These focal earthworm species, defined here according to the EFSA Guidance Document on the environmental risk assessment (ERA) of genetically modified plants, are typical for arable soils under crop rotations with maize and/or potatoes within the three regions represented by Ireland, Sweden and Spain, respectively. Focal earthworm species were selected following a matrix of four steps: Identification of functional groups, categorization of non-target species, ranking species on ecological criteria, and final selection of focal species. They are recommended as appropriate non-target organisms to assess environmental risks of genetically modified (GM) crops; in this case maize and potatoes. In total, 44 literature sources on earthworms in arable cropping systems including maize or potato from Ireland, Sweden and Spain were collected, which present information on species diversity, individual density and specific relevance for soil functions. By means of condensed literature data, those species were identified which (i) play an important functional role in respective soil systems, (ii) are well adapted to the biogeographical regions, (iii) are expected to occur in high abundances under cultivation of maize or potato and (iv) fulfill the requirements for an ERA test system based on life-history traits. First, primary and secondary decomposers were identified as functional groups being exposed to the GM crops. In a second step, anecic and endogeic species were categorized as potential species. In step three, eight anecic and endogeic earthworm species belonging to the family Lumbricidae were ranked as relevant species: Aporrectodea caliginosa, Aporrectodea rosea, Aporrectodea longa, Allolobophora chlorotica, Lumbricus terrestris, Lumbricus friendi, Octodrilus complanatus and Octolasion cyaneum. Five out of these eight species are relevant for each biogeographical region with an overlap in the species. Finally, the earthworm species Ap. caliginosa (endogeic, secondary decomposer) and L. terrestris (anecic, primary decomposer) were selected as focal species. In the Mediterranean region L. terrestris may be substituted by the more relevant anecic species L. friendi. The selected focal species are recommended to be included in a standardized laboratory ERA test system based on life-history traits. © 2016 Elsevier B.V.

This review is based on 59 papers published between 2002 and 2015, referring to about 450 treatment trains providing data regarding sludge concentrations for 169 compounds, specifically 152 pharmaceuticals and 17 personal care products, grouped into 28 different classes. The rationale of the study is to provide data to evaluate the environmental risk posed by the spreading of treated sludge in agriculture. Following discussion of the legislative scenario governing the final disposal of treated sludge in European countries and the USA, the study provides a snapshot of the occurrence of selected compounds in primary, secondary, mixed, digested, conditioned, composted and dried sludge originating in municipal wastewater treatment plants fed mainly with urban wastewater as well as in sludge-amended soil. Not only are measured values reported, but also predicted concentrations based on Kd values are reported. It emerges that in secondary sludge, the highest concentrations were found for fragrances, antiseptics and antibiotics and an attenuation in their concentrations occurs during treatment, in particular anaerobic digestion and composting. An in-depth literature survey of the (measured and predicted) Kd values for the different compounds and treated sludge are reported and an analysis of the influence of pH, redox conditions, sludge type was carried out. The data regarding measured and predicted concentrations of selected compounds in sludge-amended soil is then analyzed. Finally an environmental risk assessment posed by their occurrence in soil in the case of land application of sludge is examined, and the results obtained by different authors are compared. The most critical compounds found in the sludge-amended soil are estradiol, ciprofloxacin, ofloxacin, tetracycline, caffeine, triclosan and triclocarban. The study concludes with a focus on the main issues that should be further investigated in order to refine the environmental risk assessment.

The Ministry of Environmental Protection released a Joint Action Plan for Control of Air Pollution (Hereafter, Joint Action Plan, JAP), to reduce PM2.5 concentrations in the Beijing-Tianjin-Hebei region (BTH) during the winter of 2017. To investigate the effectiveness of the controls, we deployed an aerosol chemical speciation monitor and collected filter samples at Xianghe, a representative site for the BTH, to characterize the aerosol composition during the implementation of the JAP. Those results were compared with earlier data obtained from a literature survey and reanalysis of studies in the BTH. During several pollution episodes in the control period, the major aerosol types changed relative to the earlier studies from sulfate, oxygenated organic aerosol, and coal combustion organic aerosol to nitrate and biomass burning organic aerosol. The dominant secondary inorganic aerosol species during the JAP changed from sulfate to nitrate, and the main source for primary organic aerosol switched from coal combustion to biomass burning. These changes can be explained by the fact that the JAP controls targeted coal combustion and SO2 but not biomass burning or NOx emissions. Our evaluation of the control measures provides a scientific basis for developing new policies in the future.

Development of advanced biofuels such as bioethanol and biodiesel from renewable resources is critical for the earth's sustainable management and to slow down the global climate change by partial replacement of gasoline and diesel in the transport sector. Being a diverse group of aquatic micro-organisms, algae are the most prominent resources on the planet, distributed in an aquatic system, a potential source of bioenergy, biomass and secondary metabolites. Microalgae-based biofuel production is widely accepted as non-food fuel sources and better choice for achieving goals of incorporation of a clean fuel source into the transportation sector. The present review article provides a comprehensive literature survey as well as a novel approach on the application of microalgae for their simultaneous cultivation and bioremediation of high nutrient containing wastewater. In addition to that, merits and demerits of different existing conventional techniques for microalgae culture reactors, harvesting of algal biomass, oil recovery, use of different catalysts for transesterification reactions and other by-products recovery have been discussed and compared with the membrane-based system to find out the best optimal conditions for higher biomass as well as lipid yield. This article also deals with the use of a tailor-made membrane in an appropriate module that can be used in upstream and downstream processes during algal-based biofuels production. Such membrane-integrated system has the potential of low-cost and eco-friendly separation, purification and concentration enrichment of biodiesel as well as other valuable algal by-products which can bring the high degree of process intensification for scale-up at the industrial stage.

The environmental release of antiviral drugs is of considerable concern due to potential ecosystem alterations and the development of antiviral resistance. As a result, interest on their occurrence and fate in natural and engineered systems has grown substantially in recent years. The main scope of this review is to fill the void of information on the knowledge on the worldwide occurrence of antiviral drugs in wastewaters and natural waters and correlate their levels with their environmental fate. According to the conducted literature survey, few monitoring data exists for several European countries, such as Germany, France, and the UK. Lesser data are available for Asia, where approximately 80% of the studies focus on Japan. Several articles study the occurrence of mostly antiretroantivirals in sub-Saharan African countries, while there is a lack of data for other developing regions of the world, including the rest of Africa, South America, and the biggest part of Asia. An importantly smaller number of studies exists for North America, while no studies exist for Oceania. The against innfluenza drug oseltamivir along with its active carboxy metabolite is found to be the most studied antiviral drug. The distribution of antiviral drugs across all geographic regions varies from low ng L-1 to high μg L-1 levels, in some cases, even in surface waters. This overarching review reveals that monitoring of antiviral drugs is necessary, and some of those compounds may require toxicological attention, in the light of either spatial and temporal high concentration or potential antiviral resistance. Based on the information provided herein, the need for a better understanding of the water quality hazards posed by antiviral drugs existence in wastewater outputs and freshwater ecosystems is demosntrated. Finally, the future challenges concerning the occurrence, fate, and potential ecotoxicological risk to organisms posed by antiviral drug residues are discussed.

The Life Cycle Assessment (LCA) methodology is widely applied in several industrial sectors to evaluate the environmental performance of processes, products and services. Recently, several reports and studies have emphasized the importance of LCA in the field of engineered nanomaterials. However, to date only a few LCA studies on nanotechnology have been carried out, and fewer still have assessed aspects relating to ecotoxicity. This is mainly due to the lack of knowledge in relation on human and environmental exposure and effect of engineered nanoparticles (ENPs). This bottleneck is continued when performing Life Cycle Impact Assessment, where characterization models and consequently characterization factors (CFs) for ENPs are missing. This paper aims to provide the freshwater ecotoxicity CF for titanium dioxide nanoparticles (nano-TiO2). The USEtox™ model has been selected as a characterisation model. An adjusted multimedia fate model has been developed which accounts for nano-specific fate process descriptors (i.e. sedimentation, aggregation with suspended particle matter, etc.) to estimate the fate of nano-TiO2 in freshwater. A literature survey of toxicity tests performed on freshwater organism representative of multiple trophic levels was conducted, including algae, crustaceans and fish in order to collect relevant EC50 values. Then, the toxic effect of nano-TiO2 was computed on the basis of the HC50 value. Thus, following the principle of USEtox™ model and accounting for nano-specific descriptors a CF for the toxic impact of freshwater ecotoxicity of 0.28 PAF day m3 kg− 1 is proposed.

Pharmaceuticals and personal care products (PPCPs) along with illicit drugs (IDs) are newly recognized classes of environmental pollutants and are receiving considerable attention because of their environmental impacts: frequent occurrence, persistence and risk to aquatic life and humans. However, relatively little information is often available with regard to their possible biotic and abiotic transformation products (TPs). This lack of knowledge has resulted in a substantial amount of ongoing effort to develop methods and approaches that would assess their occurrence, degradability potential elimination mechanisms and efficiencies in sewage treatment plants as well as environmental and human health risks. In this article, an extensive literature survey was performed in order to present the current stage of knowledge and progress made in the occurrence of TPs of PPCPs and IDs in raw and treated wastewaters. Apart from the TPs resulting from structural transformations of the parent compound in the aquatic environment or in technological treatment facilities (e.g. sewage and drinking water treatment plants), free metabolites and drug conjugates formed during human metabolism have also been included in this review as they are also released into the aquatic environment through wastewaters. Their concentration levels were reported in influents and effluents of WWTPs, hospital effluents and their removals in the treatment plants were discussed. Finally, information on the toxicity of TPs has been compiled when available.

In Thailand, human excreta might be recycled into agricultural soils as a supplement to commercial fertiliser and thereby enrich the general fertility of the soils. However, for Thailand an adequate knowledge of the quality of human excreta, in order to assess its fertiliser potential, is not available. A literature survey revealed only very limited information of the chemical composition and generation rate of human excreta in South East Asia. Data from other parts of the world also lacked specific information on collection and analytical methods, or the studies were typically 20–30 years old. In the present study the composition of human excreta has been studied in three case study areas in Southern Thailand: Kuan Lang, Phattalung and Prik. The inhabitants of the three areas represent people of Southern Thailand by age, sex, occupation, religion and type of residence. Human excreta was collected and stored for 1 week from five persons in each area, who each had their own toilet and collection bucket. In parallel, a septic tank at the Observation and Protection (O&P) Centre of Songkhla (a boys prison institution) adjacent to the three study areas was used as a daily sampling point, to obtain data on average amounts of human excreta and chemical composition. Information on average values of generation rate and chemical composition was obtained as well as inter-human variation. However, no significant variation was found between the results for human excreta at the O&P Centre or from the 15 individuals. Furthermore, there was no significant influence of age, sex, occupation or religion on the chemical composition. The only significant variation was that the older people excreted larger amounts of total wet matter than the younger, which could be due to a higher water intake, in order to reduce the risk of constipation. The generation rate found was 0.6–1.2 l urine/cap/day and 120–400 g wet faeces/cap/day. The generation rate of the elements in the excreta was 7.6–7.9 g N/cap/day, 1.6–1.7 g P/cap/day, 1.8–2.7 g K/cap/day, 1.0–1.1 g S/cap/day, 0.75–1.5 g Ca/cap/day, 0.25–0.4 g Mg/cap/day, 9–16 mg Zn/cap/day, 1.4–1.5 mg Cu/cap/day, 0.3 mg Ni/cap/day, 0.02–0.03 mg Cd/cap/day, 0.07–0.14 mg Pb/cap/day, 0.01 mg Hg/cap/day and 0.8–1.1 mg B/cap/day. The metals (Ca, Mg, Zn, Cu, Ni, Cd, Pb, Hg) are mainly excreted via the faeces and the remaining elements (N, P, K, S, B) are mainly excreted via the urine. It can be concluded that human excreta constitutes a large fertiliser resource, which presently is not utilised in Thailand.

Road traffic affects the public in a wide variety of ways, many of which cause some degree of annoyance. The major disturbances to the public arising from vehicular emissions include physical effects such as the irritation of eyes and mucous membranes, visual intrusion, soiling, or more subjective impacts. A literature survey has been conducted which identified the vehicle-derived air pollutants suspected of causing some degree of nuisance to the public but also highlighted the limited data in this area. A preliminary investigation of the relationship between public attitude and pollutant concentrations has been conducted at two locations in the London Borough of Ealing and a single location in the London Borough of Haringey. A range of pollutants was monitored continuously including oxides of carbon, nitrogen and sulphur, selected volatile organic compounds and particulate matter. Traffic flows and meteorological conditions were also recorded throughout the survey period. To measure the local public opinion concerning vehicle-derived pollutants, pedestrians and occupants of residential and business premises were surveyed. The preliminary analysis of this data indicates the importance of diesel-engined vehicles to public annoyance and the significance of diesel derived particulate matter.

An empirical approach, based on a literature survey and on original data, permits the simple calculation of the net flux of any gas, reactive or inert, across an air-water interface. The only two requirements are an accurate knowledge of the concentration difference across the interface in terms of moles per cubic meter, and reasonable information about the average wind speed. The log of flux in mol m−2 s−1 plotted versus the wind speed at 10 m altitude provides a series of essentially parallel lines for the three wind speed regimes; calm, normal and storm. Two subsets of behavior for low vs high concentrations are also evident. Neither the ideality nor the chemical reactivity of the gas are factors in this approach. The method performs well for both local events and for global considerations.