14th congress of combustion by-products and their health effects-origin, fate, and health effects of combustion-related air pollutants in the coming era of bio-based energy sources

Study of the memory effect of PCDD/F during the combustion of several biomasses in a moving grate boiler

The objective of this work was to study the influence of temperature on the PCDD/Fs behavior stored in biomass ashes issued from an automatic pilot-scale wood boiler. A mixture of these ashes with a dioxin mass ratio dry based of 5.9 μg kg^-1 was used for thermal treatment at temperatures ranging between 200 and 500°C. First tests were carried out in a macro thermogravimetric analysis instrument while a couple of other tests were carried out in a quartz-lined crossed fixed-bed reactor. These treated ashes were afterwards analyzed and their dioxin mass ratio was determined. Results obtained from these both experiments are radically different: ashes treated in macro-TGA contain 18 times more PCDD/Fs than the initial non-treated ashes while those from the reactor have 84% less of PCDD/Fs. Ninety-one percent of stored PCDD/Fs in the initial ashes were eliminated after 1h at 400°C in crossed fixed-bed reactor. Macro-TGA experiments are a representation of what happens during the shutdown and cooling phase of the boiler, some areas reaching temperatures for which the formation of PCDD/Fs is optimal. Without cleaning the boiler, a memory effect on further tests is observed.

Risk Characterization and Benefit-Risk Assessment of Brominated Flame Retardant in Commercially Exploited Freshwater Fishes and Crayfish of Lake Trasimeno, Italy

Among brominated flame retardants (BFRs), polybrominateddiphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) were the most widely used in past decades. BFRs not being chemically bonded to polymers means they can easily leach from the products into the environment and bioaccumulate. Humans are exposed to flame retardants mainly through food consumption, especially fish and fish products. In the present study, the occurrence of PBDEs and HBCDs in freshwater fishes and crayfish from Lake Trasimeno (Umbria region, central Italy) was assessed according to monitoring plans recommended by European competent authorities. The dietary exposure of the central Italian population to such molecules was calculated, and the risk characterization and the benefit–risk evaluation were also assessed. A total of 90 samples were analyzed by means of gas and liquid chromatography associated with triple quadrupole mass spectroscopy. A total of 51% of samples were found positive for at least one of the congeners; the most frequently found molecule was BDE-47. The data on dietary exposure ranged from 0.138 to 1.113 pg/kg body weight/day for ∑PBDE and from 0.805 to 0.868 pg/kg body weight/day for ∑HBCD. The data show no health risks for the central Italian population consuming freshwater fish products from Lake Trasimeno in relation to exposure to PBDE and HBCD.

Fuzzy Based Prediction Model for Air Quality Monitoring for Kampala City in East Africa

The quality of air affects lives and the environment at large. Poor air quality has claimed many lives and distorted the environment across the globe, and much more severely in African countries where air quality monitoring systems are scarce or even do not exist. Here in Africa, dirty air is brought about by the growth in industrialization, urbanization, flights, and road traffic. Air pollution remains such a silent killer, especially in Africa, and if not dealt with, it will continue to lead to health issues, such as heart conditions, stroke, and chronic respiratory organ unwellness, which later result in death. In this paper, the Kampala Air Quality Index prediction model based on the fuzzy logic inference system was designed to determine the air quality for Kampala city, according to the air pollutant concentrations (nitrogen dioxide, sulphur dioxide and fine particulate matter 2.5). It is observed that fuzzy logic algorithms are capable of determining the air quality index and therefore, can be used to predict and estimate the air quality index in real time, based on the given air pollutant concentrations. Hence, this can reduce the effects of air pollution on both humans and the environment.

Polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDD), dechlorane-related compounds (DRCs), and emerging brominated flame retardants (EBFRs) in foods: The levels, profiles, and dietary intake in Latvia

This study was performed to assess the Latvian population exposure to polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDD), dechlorane-related compounds (DRCs), and emerging brominated flame retardants (EBFRs). Food items including fish, fish products, meat, dairy products, cereals and bread, eggs, vegetable oils, and sweets were analyzed for the content of these contaminants, followed by per capita intake calculations and risk assessment. The highest dietary exposure for general population was observed in the case of HBCDD, .reaching an estimated daily intake (EDI) value of 2.92 ng kg^-1 b.w. (or 3.35 ng kg^-1 b.w. if an outlying data point is included), followed by PBDEs with EDI of 1.24 ng kg^-1 b.w., including ~25% contribution of PBDE-209 to the overall EDI from PBDEs. DRCs and EBFRs were secondary contributors to the total intake of selected flame retardants (FRs), with the observed EDIs of 0.46 and 0.47 ng kg^-1 b.w, respectively. The obtained occurrence data and risk characterization according to the European Food Safety Authority (EFSA) approach showed the calculated margin of exposure (MOE) values higher than the critical values for PBDE-47, -99 and -153as well as for HBCDD, indicating that the estimated dietary exposures are unlikely to be of significant health concern for the Latvian population. At the same time, it should be pointed out that the risk assessment was performed only for five out of the twenty-five selected halogenated flame retardants (HFRs), while cumulative effects due to the potential presence of other HFRs and their biodegradation products were not considered.

Sorption and release process of polybrominated diphenyl ethers (PBDEs) from different composition microplastics in aqueous medium: Solubility parameter approach

Microplastics represent a growing environmental concern in the aquatic environment due to its size resemblance to microplankton in addition to its ability to act as concentrators of persistent organic pollutants (POPs). Among them, polybrominated diphenyl ethers (PBDEs) stand out as POPs with dangerous levels in the aquatic environment. In this paper we have developed a methodology for studying the sorption and extraction process of twelve congeners of PBDE from four microplastics: polyethylene terephthalate (PET), polypropylene (PP), low density polyethylene (LDPE) and polystyrene (PS). We have proved that there is a dependence between the polymer composition and the solvent used for the extraction of the analytes. The extraction is function of the ability of the solvent to partially or totally dissolve the plastic that will allow the analyte to have a greater capacity to be released from the polymer structure. The solution of the polymer is achieved by making the free energy (ΔG, or Gibbs potential) of the system negative making the process occurs spontaneously, this will depend on the solubility parameter (∂), specific of both, solvent and polymer. Therefore, this study helps to determine which methodology to be applied for the extraction of pollutants before the start of the analysis. This approach has been applied to microplastic samples collected in different locations in the four oceans and collected from the Barcelona World Race (BWR) 2014-2015 sailing race.

Occurrence, formation, environmental fate and risks of environmentally persistent free radicals in biochars

Biochars are used globally in agricultural crop production and environmental remediation. However, environmentally persistent free radicals (EPFRs), which are stable emerging pollutants, are generated as a characteristic feature during biomass pyrolysis. EPFRs can induce the formation of reactive oxygen species, which poses huge agro-environmental and human health risks. Their half-lives and persistence in both biochar residues and in the atmosphere may lead to potentially adverse risks in the environment. This review highlights the comprehensive research into these bioreactive radicals, as well as the bottlenecks of biochar production leading up to the formation and persistence of EPFRs. Additionally, a way forward has been proposed, based on two main recommendations. A global joint initiative to create an all-encompassing regulations policy document that will improve both the technological and the quality control aspects of biochars to reduce EPFR generation at the production level. Furthermore, environmental impact and risk assessment studies should be conducted in the extensive applications of biochars in order to protect the environmental and human health. The highlighted key research directions proposed herein will shape the production, research, and adoption aspects of biochars, which will mitigate the considerable concerns raised on EPFRs.

Landfill air and odour emissions from an integrated waste management facility

A mixture of gases and obnoxious odours are major components of landfill emission. A dispersion modelling on air pollutants and odour emissions anticipated from a proposed Integrated Waste Management Facility was conducted considering five operating scenarios. Impacts of the predicted ground level concentrations of air pollutants (including carbon monoxide, CO; oxides of nitrogen, NOX; sulphur dioxide, SO2; particulate matter, PM and hydrocarbons, HC) and odour on ambient air quality were investigated using the 10-min 1 OU/m3 odour limit, CH4 Lower Explosive Limit (LEL) and the daily limits of CO, NOx, SO2, PM and HC. The anticipated maximum ground level concentration of emitted odour and CH4 are 0.0040 OU/m3 and 0.0349 ppm, respectively. Simultaneous operations of all the major components of the facility will generate the daily maximum concentrations of 7.34, 2.60, 7.31, 29.72 and 0.42 μg/m3, for CO, NOX, SO2, PM and HC, respectively. Generally, the facility impacts on ambient air quality will be within the acceptable limit.

Bioremediation of steel plant wastewater and enhanced electricity generation in microbial desalination cell

Microbial desalination cell (MDC) is a propitious technology towards water desalination by utilizing wastewater as an energy source. In this study, a multi-chambered MDC was used to bioremediate steel plant wastewater using the same wastewater as a fuel for anodic bacteria. A pure culture of Pseudomonas putida MTCC 1194 was isolated and inoculated to remove toxic phenol. Three different inoculum conditions, namely P. putida (INC-A), a mixture of P. putida and activated sludge (INC-B), and activated sludge alone (INC-C) were employed in an anodic chamber to mainly compare the electricity generation and phenol degradation in MDCs. The study revealed the maximum phenol removal of 82 ± 2.4%, total dissolved solids (TDS) removal of 68 ± 1.5%, and power generation of 10.2 mW/m² using INC-B. The synergistic interactions between microorganisms, can enhance the toxic phenol degradation and also electricity generation in MDC for onsite wastewater application.

Diesel exhaust exposure, its multi-system effects, and the effect of new technology diesel exhaust

Exposure to diesel exhaust (DE) from vehicles and industry is hazardous and affects proper function of organ systems. DE can interfere with normal physiology after acute and chronic exposure to particulate matter (PM). Exposure leads to potential systemic disease processes in the central nervous, visual, hematopoietic, respiratory, cardiovascular, and renal systems. In this review, we give an overview of the epidemiological evidence supporting the harmful effects of diesel exhaust, and the numerous animal studies conducted to investigate the specific pathophysiological mechanisms behind DE exposure. Additionally, this review includes a summary of studies that used biomarkers as an indication of biological plausibility, and also studies evaluating new technology diesel exhaust (NTDE) and its systemic effects. Lastly, this review includes new approaches to improving DE emissions, and emphasizes the importance of ongoing study in this field of environmental health.

Comparison of Mutagenic Activities of Various Ultra-Fine Particles

Air pollution is increasing, along with consumption of fossil fuels such as coal and diesel gas. Air pollutants are known to be a major cause of respiratory-related illness and death, however, there are few reports on the genotoxic characterization of diverse air pollutants in Korea. In this study, we investigated the mutagenic activity of various particles such as diesel exhaust particles (DEP), combustion of rice straw (RSC), pine stem (PSC), and coal (CC), tunnel dust (TD), and road side dust (RD). Ultra-fine particles (UFPs) were collected by the glass fiber filter pad. Then, we performed a chemical analysis to see each of the component features of each particulate matter. The mutagenicity of various UFPs was determined by the Ames test with four Salmonella typhimurium strains with or without metabolic activation. The optimal concentrations of UFPs were selected based on result of a concentration decision test. Moreover, in order to compare relative mutagenicity among UFPs, we selected and tested DEP as mutation reference. DEP, RSC, and PSC induced concentration-dependent increases in revertant colony numbers with TA98, TA100, and TA1537 strains in the absence and presence of metabolic activation. DEP showed the highest specific activity among the particulate matters. In this study, we conclude that DEP, RSC, PSC, and TD displayed varying degrees of mutagenicity, and these results suggest that the mutagenicity of these air pollutants is associated with the presence of polycyclic aromatic hydrocarbons (PAHs) in these particulate matters.

The National Institute of Environmental Health Sciences Superfund Research Program: a model for multidisciplinary training of the next generation of environmental health scientists

The National Institute of Environmental Health Sciences (NIEHS) Superfund Research Program (SRP) funds university-based, multidisciplinary research on human health and environmental science and engineering with the central goals to understand how hazardous substances contribute to disease and how to prevent exposures to these environmental chemicals. This multi-disciplinary approach allows early career scientists (e.g. graduate students and postdoctoral researchers) to gain experience in problem-based, solution-oriented research and to conduct research in a highly collaborative environment. Training the next generation of environmental health scientists has been an important part of the SRP since its inception. In addition to basic research, the SRP has grown to include support of broader training experiences such as those in research translation and community engagement activities that provide opportunities to give new scientists many of the skills they will need to be successful in their field of research. Looking to the future, the SRP will continue to evolve its training component by tracking and analyzing outcomes from its trainees by using tools such as the NIEHS CareerTrac database system, by increasing opportunities for trainees interested in research that goes beyond US boundaries, and in the areas of bioinformatics and data integration. These opportunities will give them the skills needed to be competitive and successful no matter which employment sector they choose to enter after they have completed their training experience.