To narrow the gap in our understanding of potential oxidative properties associated with Electronic Nicotine Delivery Systems (ENDS) i.e. e-cigarettes, we employed semi-quantitative methods to detect oxidant reactivity in disposable components of ENDS/e-cigarettes (batteries and cartomizers) using a fluorescein indicator. These components exhibit oxidants/reactive oxygen species reactivity similar to used conventional cigarette filters. Oxidants/reactive oxygen species reactivity in e-cigarette aerosols was also similar to oxidant reactivity in cigarette smoke. A cascade particle impactor allowed sieving of a range of particle size distributions between 0.450 and 2.02 μm in aerosols from an e-cigarette. Copper, being among these particles, is 6.1 times higher per puff than reported previously for conventional cigarette smoke. The detection of a potentially cytotoxic metal as well as oxidants from e-cigarette and its components raises concern regarding the safety of e-cigarettes use and the disposal of e-cigarette waste products into the environment.

Indoor air pollution in university research laboratories may be important to building occupants, especially for those who work in the laboratories. In this study, indoor air quality (IAQ) and indoor environmental comfort were investigated in research laboratories of two departments at a university. PM2.5, PM10, TVOC (total volatile organic compounds), and CO concentrations, and three comfort variables which are temperature, relative humidity, and CO2 were measured. PM2.5 concentration was determined gravimetrically by collecting particles on glass fiber filters, whereas the remaining pollutants and comfort variables were measured using a monitoring device. IAQ measurements showed that levels of all pollutants were under the limits in both of the departments except for TVOC in one laboratory which had a mean concentration of 182ppb. The comfort variables were in the comfort ranges for laboratories in both of the departments except for temperature in one laboratory with a mean value of 30 °C. In conclusion, measures are needed for extensive uses of organic solvents because ventilation may not be sufficient to keep VOC concentrations within the limits, and to provide thermal comfort.

To determine the chemical compositions and source identification of PM2.5 and PM2.5–10 fractions, airborne particulate matter (PM) samples were collected from May, 2011 through April, 2012 at three sites: up and downwind and within a scrap iron and steel smelting industry, Ife–Ibadan highway, south western Nigeria. Samples of PM2.5 (fine) and PM2.5–10 (coarse) were collected on Nuclepore polycarbonate filters using a low volume GENT sampler equipped with a stacked filter unit (SFU). A total of 200 samples were collected (100 of each fraction). The mass concentration of the sampled fine and coarse PM fraction ranged between 14.4–986.5μg/m3 and 11.2–3 250μg/m3, respectively. These values exceed the permissible daily limit (NAAQS) of 35μg/m3 for PM2.5 and 150μg/m3 for PM10. The samples were analyzed for black carbon (BC) using an optical transmissometer and for elemental concentrations using X–Ray Fluorescence (XRF). The size–resolved data sets were analyzed using Positive Matrix Factorization (PMF) to identify possible sources and estimate the contribution of these sources to the fine and coarse PM mass concentrations. Four source categories, providing stable profiles, were identified for both fine and coarse fractions. The identified sources and their contributions for the fine fraction are coking coal (83%), soil (10%), metallurgical industry (6%), and electronic waste processing (1%). For the coarse fraction, the identified sources are metallurgical production plus electronic waste (53%), suspended input materials (28%), soil (18%), and galvanized steel scrap with cadmium (1%). Conditional probability function (CPF) identified the local sources for both the fine and coarse PM samples. This work presents the first known major use of PMF in Nigeria for source identification in particulate matter (PM) studies.

Atmospheric deposition can be an important source of ions to terrestrial and aquatic ecosystems. Previous studies have indicated that dry deposition of ions in and near large cities is greater than in nearby rural areas. However, few studies have compared dry deposition in and near smaller cities. We measured dry deposition of ions at various distances from Greenville, a smaller city in the piedmont of northwestern South Carolina. Dry deposition was estimated by exposure of artificial surfaces (glass Petri plates and paper filters) to the atmosphere at 13 locations during June–July 2008. Petri plates were expected to collect dust particles primarily, whereas filters were expected to collect both dust and gases. Fluxes measured by filters were significantly greater than those measured by Petri plates for nitrate and ammonium, suggesting that dry deposition of nitrogen in gases exceeded dry deposition in dust. Dry deposition of ammonium and nitrate declined significantly with distance from Greenville, and rates were significantly higher at urban than at rural locations. Also, dry deposition rates of ammonium correlated positively with road densities and traffic volumes around sampling locations, suggesting that automobiles were important sources of ammonia gas. Relationships between ammonium deposition and urban land cover and roads were stronger than for nitrate deposition, perhaps reflecting the influence of automobiles using catalytic converters. Base cation concentrations in dry deposition typically were below detection, precluding flux calculations. Overall, our results provide evidence that smaller cities influence atmospheric deposition of nitrogen, though perhaps not as strongly as larger cities.

Activated carbon is investigated as adsorptive barrier for organic micropollutants (OMP) within the Berlin water cycle. In a pilot plant using granular activated carbon (GAC) as upper layer in dual-media filtration, OMP concentrations in treated wastewater could be reduced without any negative impact on filtration efficiency. OMP breakthroughs occurred after shorter runtimes than estimated according to isotherm experiments with powdered activated carbon (PAC). Batch adsorption tests comparing the used GAC to new GAC showed that the capacity of the used GAC was not exhausted, indicating that besides direct site competition, pore blocking is also responsible for the poor GAC performance. A pilot plant application of PAC of the same type as GAC showed significantly higher OMP removals at lower dosages, taking advantage of immobilization of PAC particles in the filters. Both PAC and GAC applications can be integrated into tertiary wastewater treatment without significant constructional changes.

Advanced wastewater treatment with granular activated carbon (GAC) is a promising option to reduce emissions of organic micropollutants (OMP) into the aquatic environment. Frequent back-washes of the GAC filters are required due to high particle concentration in the treated wastewater but lead to stratification. Differences in adsorption capacities of individual strata are not known. The present study aimed at investigating physical and chemical differences at different filter depths of a stratified GAC filter. Two different commercial products were stratified during repeated filter bed expansions and sectioned into vertical fractions. Bulk densities, grain size distributions and ash contents of the individual fractions differed significantly. Adsorption tests with pulverized GAC from different levels showed great vertical differences in adsorption properties. OMP removals determined in the upper part of a GAC filter therefore cannot be extrapolated downwards. Both physical and chemical vertical heterogeneities with regard to adsorption capacities and residence times at different filter depths should be considered in the filter design, in the monitoring of a GAC filter, and in the interpretation of the GAC filter performance. Good correlations between abatements of UV light absorption and OMP removals were found for the virgin GAC throughout the non-uniform filter.

Chemical contamination of water resources on the planet generates a range of environmental disturbances which impair ecosystems. Humans ingest such chemicals often present in water. Conventional treatments fail to remove these contaminants from water, requiring complementary methods such as activated carbon filters, reverse osmosis, or distillation, which are expensive and seldom used in the public water supply. In recent years, there has been a search for alternative eco-friendly, low-cost methods which can effectively remove these contaminants. This study was conducted to test the effectiveness of biotite (black mica), an igneous mineral of the mica group, in removing pesticides from water. A trial was designed to assess the rate of pesticide removal using a methodology based on axes of variation of pH, temperature, concentration, and time. The pesticides tested were atrazine, fluazifop-p-butyl, lambda-cyhalothrin, chlorpyrifos, and lactofen. The results showed higher removal rates in acidic conditions (pH 3) and temperatures between 20 and 30 °C, requiring about 6 h to reach maximum adsorption. More than 80 % of all the pesticides were adsorbed. The best result was obtained for fluazifop (94.2 %) in 6 h, under pH 3, and temperature of 25 °C. The study revealed that biotite has a high absorption capacity of complex and varied compounds. These findings signal the need for further studies and tests. Due to the high cost of pesticide analysis, which can only be made using a chromatograph mass spectrometer, financial resources will be required.

Electrolytic manganese residue (EMR) is a solid waste found in filters after sulphuric acid leaching of manganese carbonate ore, which mainly contains manganese and ammonia nitrogen and seriously damages the ecological environment. This work demonstrated the use of electrokinetic (EK) remediation to remove ammonia nitrogen and manganese from EMR. The transport behavior of manganese and ammonia nitrogen from EMR during electrokinetics, Mn fractionation before and after EK treatment, the relationship between Mn fractionation and transport behavior, as well as the effects of electrolyte and pretreatment solutions on removal efficiency and energy consumption were investigated. The results indicated that the use of H₂SO₄ and Na₂SO₄ as electrolytes and pretreatment of EMR with citric acid and KCl can reduce energy consumption, and the removal efficiencies of manganese and ammonia nitrogen were 27.5 and 94.1 %, respectively. In these systems, electromigration and electroosmosis were the main mechanisms of manganese and ammonia nitrogen transport. Moreover, ammonia nitrogen in EMR reached the regulated level, and the concentration of manganese in EMR could be reduced from 455 to 37 mg/L. In general, the electrokinetic remediation of EMR is a promising technology in the future.

Comprehensive two-dimensional gas chromatography (GC × GC) utilizing a flow modulator was applied to study particulate polycyclic aromatic hydrocarbons (PAHs) and n-alkanes in the urban atmosphere. Samples were collected onto quartz fiber filters using a PM2.5 sampler at Megacity Shanghai, China. Sample preparation included extraction into n-hexane-dichloromethane mixture and cleanup on silver-impregnated silica column. Analyses were performed well with GC × GC-FID and GC × GC-TOFMS equipment. Average particulate PAHs and n-alkane concentrations were in the range of 40–100 ng/m³and 120–500 pg/m³, respectively. It is alarming to note that PAHs and n-alkane concentrations were increasing with urban PM2.5 values and exceeded the air quality standards in many sampling events. Among them, 2-ring, 3-ring, and 4-ring PAHs accounted for the majority of total PAHs, and C10–15 accounted for the majority of particulate n-alkanes. Potential sources of PAHs in PM2.5 were identified using the diagnostic ratios between PAHs. Local emission sources such as combustion from gasoline and diesel engines were the main contributors of particulate-associated PAHs, while long-range transport had minor contribution to the particulate PAHs. Additionally, we determined the overall carcinogenicity of the samples based on PAH concentrations by a dose addition model and found that the overall carcinogenicity during polluted period was obviously higher than during good air quality period.

An intensive measurement campaign was undertaken to characterize eight fractions of organic carbon (OC) and elemental carbon (EC) in particulate matter (PM) at four urban sites with different pollution characteristics during summer, post-monsoon, and winter at Kanpur, India. Speciation samplers were used to collect particulate samples on quartz filters followed by analysis of OC and EC using Interagency Monitoring of Protected Visual Environments (IMPROVE)-based thermal/optical reflectance (TOR) method. Based on 24-h average results at each site, the highest levels of OC and EC were observed during winter as 96.7 ± 26.9 and 31.8 ± 9.8 μg/m³ at residential site and traffic site, respectively. The levels of OC at residential sites during winter appeared to be more than twice of that during summer. The site close to the road traffic had the least value of OC/EC, as 1.77 ± 0.28 during post-monsoon, and the site influenced by emissions of domestic cooking and heating had the highest value of OC/EC, as 4.05 ± 0.79 during winter. The average abundances of OC1, OC2, OC3, OC4, OP, EC1, EC2, and EC3 in total carbon (TC) at all sites for three seasons were 10.03, 19.04, 20.03, 12.32, 10.53, 33.39, 3.21, and 1.99 %, respectively. A sharp increase in levels of OC1 and EC1-OP during winter at two residential sites revealed that biomass burning could be a significant contributor to carbonaceous aerosols. From the application of EC-tracer method, it was observed that contribution of secondary organic carbon (SOC) to PM mass increased from 5 % during post-monsoon to 16 % during winter at residential sites and from 2 % during post-monsoon to 7 % during winter at traffic sites. Therefore, it could be inferred that increase in primary emissions coupled with unfavorable meteorological conditions could cause particle agglomeration and hygroscopic growth, leading to unpleasant pollution episode during winter.