Presently, many pharmaceuticals are listed as emerging contaminants since they are considered to be great potential threats to environmental ecosystems. These contaminants, thus, present significant research interest due to their extensive use and their physicochemical and toxicological properties. This review discusses a whole range of findings that address various aspects of the usage, occurrence, and potentially environmental risks of pharmaceuticals released from various anthropogenic sources, with emphasis on the aquatic systems in Vietnam. The published information and collected data on the usage and occurrence of antibiotics and synthetic hormone in effluents and aquatic systems of Vietnam is reported. This is followed by a potential ecological risk assessment of these pollutants. The extensive use of antibiotics and synthetic hormones in Vietnam could cause the discharge and accumulation of these contaminants in the aquatic systems and potentially poses serious risks for ecosystems. Vietnam is known to have extensively used antibiotics and synthetic hormones, so these contaminants are inevitably detected in aquatic systems. Thus, an appropriate monitoring program of these contaminants is urgently needed in order to mitigate their negative effects and protect the ecosystems.

Filter-feeding bivalves have been used extensively as an indicator of ecosystem condition and in management of estuarine environments. The current study aimed to determine whether sedimentary metals could predict metal concentrations in tissue of filter-feeding mussels (Mytilus galloprovincialis) and to identify areas of the estuary where mussel consumption posed a human health risk. Mussel tissue Cu and Zn concentrations (wet weight) were below guideline values for human consumption in all parts of the waterway, whereas Pb tissue concentrations exceed these guidelines (2.0 μg g(-1) wet weight) in the upper reaches of some embayments of the estuary. Concentrations of Cu and Pb in the fine fraction (<62.5 μm) of bottom sediment reasonably predicted concentrations (dry weight) of these metals in mussel tissue (r (2) = 0.460 and p = 0.001 and r (2) = 0.669 and p < 0.0001, respectively) as these materials are resuspendable and available to filter-feeding estuarine animals, whereas total sediment and mussel tissue were poorly related. Lead concentrations (>350 μg g(-1)) in fine sediments indicated areas of this estuary where human health was at risk due to high tissue concentrations of this metal. These results give encouragement for the use of the metal concentration in fine sediments as an indicator of estuarine condition and risk to human health in this waterway. Mussels were distributed in all parts of the estuary, even in areas where metal concentrations exceeded sediment quality guidelines.

In recent years, some perfluorinated compounds (PFCs) have been identified as potentially hazardous substances which are harmful to the environment and human health. According to limited data, PFC levels in humans could be influenced by several determinants. However, the findings are inconsistent. In the present study, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) were measured in paired maternal and cord serum samples (N = 237) collected between 1978 and 2001 in Southern Sweden to study the relationship between these and to investigate several potential determinants of maternal and fetal exposure to PFCs. Time trends of PFCs in Swedish women were also evaluated. The study is a part of the Fetal Environment and Neurodevelopment Disorders in Epidemiological Research project. PFOS, PFOA, and PFNA levels (median) were higher in maternal serum (15, 2.1, and 0.24 ng/ml, respectively) than in cord serum (6.5, 1.7, and 0.20 ng/ml, respectively). PFC levels were among the highest in women originating from the Nordic countries and the lowest in women from the Middle East, North Africa, and sub-Saharan Africa. Multiparous women had lower serum PFOA levels (1.7 ng/ml) than primiparous women (2.4 ng/ml). Maternal age, body mass index, cotinine levels, and whether women carried male or female fetuses did not affect serum PFC concentrations. Umbilical cord serum PFC concentrations showed roughly similar patterns as the maternal except for the gestational age where PFC levels increased with advancing gestational age. PFOS levels increased during the study period in native Swedish women. In summary, PFOS levels tend to increase while PFOA and PFNA levels were unchanged between 1978 and 2001 in our study population. Our results demonstrate that maternal country of origin, parity, and gestational age might be associated with PFC exposure.

The purpose of the study was the experimental evaluation of ultrafiltration as a potential innovative technology for the removal of organic matter of around 15,000 mg chemical oxygen demand (COD) per liter in the polymer industry wastewater. Particle size distribution (PSD) analysis served as the major experimental instrument along with conventional chemical settling. Biodegradation characteristics of the remaining COD after ultrafiltration were determined by model interpretation of the corresponding oxygen uptake rate (OUR) profile. The study first involved a detailed characterization of the polymer wastewater including PSD analysis of the COD content. Chemical treatability was investigated using lime alone and with ferric chloride as coagulants followed with a PSD assessment of the chemically settled effluent. Modeling of the OUR profile generated by the ultrafiltration effluent defined related biodegradation kinetics and provided information on the overall COD removal potential. PSD analysis indicated that more than 70 % of the total COD accumulated in the 220- to 450-nm size range. It indicated that ultrafiltration was potentially capable of removing more than 90 % of the COD with an effluent lower than 1,500 mg COD/L. Chemical settling with 750 mg/L of FeCl₃ dosing at a pH of 7.0 provided a similar performance. The ultrafiltration effluent included mainly hydrolysable COD and proved to be biodegradable, with the process kinetics compatible with domestic sewage. PSD evaluation proved to be a valuable scientific instrument for underlining the merit of ultrafiltration as the appropriate innovative technology for polymer wastewater, removing the major portion of the COD in a way that is suitable for recovery and reuse and producing a totally biodegradable effluent.

As plants constitute the foundation of the food chain, concerns have been raised about the possibility of toxic concentrations of metals and metalloids being transported from plants to the higher food chain strata. In this perspective, the use of important phytotoxicity endpoints may be of utmost significance in assessing the hazardous nature of metals and metalloids and also in developing ecological soil screening levels. The current study aimed to investigate the role of glutathione (GSH) and its associated enzymes in the metabolic adaptation of two grass species namely Eriophorum angustifolium Honck. and Lolium perenne L. to metals and metalloids stress in the vicinity of a chemical industrial complex (Estarreja, Portugal). Soil and plant samples were collected from contaminated (C) and non-contaminated (reference, R) sites, respectively, near and away from the Estarreja Chemical Complex, Portugal. Soils (from 0 to 10 and 10 to 20 cm depths) were analyzed for pH, organic carbon, and metals and metalloids concentrations. Plant samples were processed fresh for physiological and biochemical estimations, while oven-dried plant samples were used for metals and metalloids determinations following standard methodologies. Both soils and plants from the industrial area exhibited differential concentrations of major metals and metalloids including As, Cu, Hg, Pb, and Zn. In particular, L. perenne shoot displayed significantly higher and lower concentrations of Pb and As, respectively at contaminated site (vs. E. angustifolium). Irrespective of sites, L. perenne shoot exhibited significantly higher total GSH pool, oxidized glutathione (GSSG) and oxidized protein (vs. E. angustifolium). Additionally, severe damages to photosynthetic pigments, proteins, cellular membrane integrity (in terms of electrolyte leakage), and lipid peroxidation were also perceptible in L. perenne shoot. Contrarily, irrespective of the sites, activities of catalase and GSH-regenerating enzyme, GSH reductase, and GSH-metabolizing enzymes such as GSH peroxidase and GSH sulfotransferase were significantly higher in shoot of E. angustifolium. Despite the higher total GSH content, L. perenne is vulnerable to multi-metals-induced stress in comparison to E. angustifolium as depicted by increased GSH- and protein oxidation, low reactive oxygen radical-processing potential (exhibited in terms of low catalase activity) and poor GSH pool utilization efficiency (in terms of lower GSH-associated enzymes activities). The outcome of the present study may be significant for understanding vital GSH-mediated metals and metalloids tolerance mechanisms in plants as well as their unsuitability for animal consumption due to higher metals and metalloids burdens.

Phenolic compounds are contaminants frequently found in water and soils. In the last years, some technologies such as phytoremediation have emerged to remediate contaminated sites. Plants alone are unable to completely degrade some pollutants; therefore, their association with rhizospheric bacteria has been proposed to increase phytoremediation potential, an approach called rhizoremediation. In this work, the ability of two rhizobacteria, Burkholderia kururiensis KP 23 and Agrobacterium rhizogenes LBA 9402, to tolerate and degrade phenolic compounds was evaluated. Both microorganisms were capable of tolerating high concentrations of phenol, 2,4-dichlorophenol (2,4-DCP), guaiacol, or pentachlorophenol (PCP), and degrading different concentrations of phenol and 2,4-DCP. Association of these bacterial strains with B. napus hairy roots, as model plant system, showed that the presence of both rhizospheric microorganisms, along with B. napus hairy roots, enhanced phenol degradation compared to B. napus hairy roots alone. These findings are interesting for future applications of these strains in phenol rhizoremediation processes, with whole plants, providing an efficient, economic, and sustainable remediation technology.

A new polyclonal antibody (pAb) was prepared and used for the determination of polychlorinated biphenyls (PCBs) in air samples to promote the application of immunoassay technology in the determination of PCBs. Three PCB congeners immunogen mixture was used to stimulate immune responses in rabbits. The specific pAb to PCBs was obtained and used to develop an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA). A standard curve for Aroclor 1248 was prepared using concentrations ranging from 0.1 to 100 μg L⁻¹. The average IC₅₀ value was 16.21 μg L⁻¹ and the limit of detection at 10 % inhibition (IC₉₀) was 0.069 μg L⁻¹. The entire procedure was then evaluated using spiked air samples. The recoveries of Aroclor 1248 at various spiking levels in the air samples ranged from 84 to 113 %, with relative standard deviations of 3 to 6 %. Under optimum conditions, the cross-reactivity profiles of the assays were obtained using three selected congeners, four Aroclor products, and other structurally related compounds of PCBs. The assays were found to be highly specific for PCB congeners and Aroclors 1248 and 1242. The air samples were then analyzed using gas chromatography coupled with high-resolution mass spectrometry to confirm the ic-ELISA results. The attained results demonstrated that the proposed method was an effective and inexpensive technique for the PCBs determination in air samples.

Spent sorbents in water treatment processes have potential risks to the environment if released without proper treatment. The aim of this work was to investigate the potential regeneration of commercially prepared nano-TiO (anatase) for the removal of Pb (II), Cu (II), and Zn (II) by pH 2 and ethylenediaminetetraacetic acid (EDTA) solutions. The percent of metal adsorption/desorption decreased with the increasing number of regeneration cycles, and the extent of decrease varied for each metal. Competitive effects were observed for the adsorption/desorption of different metals when the nano-TiO was regenerated by EDTA solutions. Nano-TiO was able to treat simulated metal polluted water with greater than 94 % adsorption and greater than 92 % desorption after four cycles of regeneration using pH 2 solution. These results demonstrated that nano-TiO can be regenerated and reused using pH 2 solution compared to an EDTA solution for aquatic metal removal, which makes nanosorbents promising and economically and environmentally more attractive in the application of water purification.

The sustainable management of chemicals and their associated wastes—especially legacy stockpiles—is always challenging. Developing countries face particular difficulties as they often have insufficient treatment and disposal capacity, have limited resources and many lack an appropriate and effective regulatory framework. This paper describes the objectives and the approach of the Egyptian–German Twinning Project under the European Neighbourhood Policy to improve the strategy of managing hazardous substances in the Egyptian Environmental Affairs Agency (EEAA) between November 2008 and May 2011. It also provides an introduction to the Republic of Egypt’s legal and administrative system regarding chemical controls. Subsequently, options for a new chemical management strategy consistent with the recommendations of the United Nations Chemicals Conventions are proposed. The Egyptian legal and administrative system is discussed in relation to the United Nations’ recommendations and current European Union legislation for the sound management of chemicals. We also discuss a strategy for the EEAA to use the existing Egyptian legal system to implement the United Nations’ Globally Harmonized System of Classification and Labelling of Chemicals, the Stockholm Convention and other proposed regulatory frameworks. The analysis, the results, and the recommendations presented may be useful for other developing countries in a comparable position to Egypt aspiring to update their legislation and administration to the international standards of sound management of chemicals.

The adsorption of Pb(II) onto the surface of microwave-assisted activated carbon was studied through a two-layer feedforward neural network. The activated carbon was developed by microwave activation of Acacia auriculiformis scrap wood char. The prepared adsorbent was characterized by using Brunauer–Emmett–Teller (BET) surface area analyzer, scanning electron microscope (SEM), and X-ray difractometer. In the present study, the input variables for the proposed network were solution pH, contact time, initial adsorbate concentration, adsorbent dose and temperature, whereas the output variable was the percent Pb(II) removal. The network had been trained by using different algorithms and based on the lowest mean squared error (MSE) value and validation error, resilient backpropagation algorithm with 12 neurons in the hidden layer was selected for the present investigation. The tan sigmoid and purelin transfer function were used in the hidden and the output layers of the proposed network, respectively. The model predicted and experimental values of the percent Pb(II) removal were also compared and both the values were found to be in reasonable agreement with each other. The performance of the developed network was further improved by normalizing the experimental data set and it was found that after normalization, the MSE and validation error were reduced significantly. The sensitivity analysis was also performed to determine the most significant input parameter.