Characterization of spatial impact of particles emitted from a cement material production facility on outdoor particle deposition in the surrounding community

The objective of this study was to estimate the contribution of a facility that processes steel production slag into raw material for cement production to local outdoor particle deposition in Camden, NJ. A dry deposition sampler that can house four 37-mm quartz fiber filters was developed and used for the collection of atmospheric particle deposits. Two rounds of particle collection (3-4 weeks each) were conducted in 8-11 locations 200-800 m downwind of the facility. Background samples were concurrently collected in a remote area located -2 km upwind from the facility. In addition, duplicate surface wipe samples were collected side-by-side from each of the 13 locations within the same sampling area during the first deposition sampling period. One composite source material sample was also collected from a pile stored in the facility. Both the bulk of the source material and the < 38 microm fraction subsample were analyzed to obtain the elemental source profile. The particle deposition flux in the study area was higher (24-83 mg/m2 x day) than at the background sites (13-17 mg/m2day). The concentration of Ca, a major element in the cement source production material, was found to exponentially decrease with increasing downwind distance from the facility (P < 0.05). The ratio of Ca/Al, an indicator of Ca enrichment due to anthropogenic sources in a given sample, showed a similar trend. These observations suggest a significant contribution of the facility to the local particle deposition. The contribution of the facility to outdoor deposited particle mass was further estimated by three independent models using the measurements obtained from this study. The estimated contributions to particle deposition in the study area were 1.8-7.4% from the regression analysis of the Ca concentration in particle deposition samples against the distance from the facility, 0-11% from the U.S. Environmental Protection Agency (EPA) Chemical Mass Balance (CMB) source-receptor model, and 7.6-13% from the EPA Industrial Source Complex Short Term (ISCST3) dispersion model using the particle-size-adjusted permit-based emissions estimates.     

Formulation factors that can reduce the formation of the phytotoxic impurity, N,N'-dibutylurea, from benomyl

Fungicide benomyl is easily decomposed to carbendazim (MBC) and butyl isocyanate (BIC) in formulation, BIC is further hydrolyzed to butylamine. The BIC also reacts with butylamine to form N,N'-dibutylurea (DBU), a phytotoxic compound. The purpose of this study was to investigate the effects of selected additives and the manufacturing method of benomyl water dispersible granules (WG) on reducing DBU content in benomyl formulations. The manufacturing methods studied were granulation by extrusion, fluid bed spray, and spray dry. For the extrusion method, each benomyl powder formulation was homogenized by kneading with 20% v/w of 95% ethanol instead of water. After granulation, the percentages of the active ingredient benomyl and its degradation product carbendazim in each formulation were determined. For the fluid bed spray method, two formulations of wettable powders were formed. The first sample was granulated using 5% Na(2)SO(4) as the binder solution; the second sample used 2% urea. Changes in the active ingredient content after granulation were determined for each sample. For the spray dry method, four basic formulations of 70% benomyl, 5% sodium dodecyl sulfate (SDS) and 10% or 20% sodium sulfate were prepared, to study the effects of HMTA, urea and dispersant on reducing DBU formation in formulation. The DBU content of each formulation was measured for the fresh samples and after 1 year of storage. The results showed that urea had a stabilizing effect on benomyl, and reduced DBU formation. BIC increased benomyl yield during manufacturing, which reduced DBU content in fresh samples but allowed a greater potential for future DBU formation since it did not stabilize the extra benomyl. HMTA was found to reduce DBU in both aqueous BIC and prepared formulations. The study discusses how each of the selected constituents affected DBU formation and how commercial formulations can be improved to reduce DBU formation. From this study, it is clear that a safer benomyl formulation can be developed.     

Biofouling attractants from a brown marine alga Ecklonia cava

In recent years, industrial pollutants and the mountain forest fire ashes released into seawater cause damage to the marine environment, mainly it reduces the algal productivity in the inter tidal region. To get recover from the stress due to pollutants and to increase the growth and development of biofouling algae (benthic organisms), Ecklonia cava extract was investigated for its biofouling attracting efficiency. Bioactive guided fractions of E. cava extract derived from column chromatography were tested against spore attachment of a fouling alga, Ulva pertusa. Fraction B showed increased spore attachment rate with a maximum of 92 +/- 5%. This fraction was further analysed on HPLC, GC-Mass and NMR, deduced as pentadecanoic acid.     

Combustion modeling and performance evaluation in a full-scale rotary kiln incinerator.

This work summarizes the results of numerical investigations and in situ measurements for turbulent combustion in a full-scale rotary kiln incinerator (RKI). The three-dimensional (3D) governing equations for mass, momentum, energy, and species, together with the kappa - epsilon turbulence model, are formulated and solved using a finite volume method. Volatile gases from solid waste were simulated by gaseous CH4 distributed nonuniformly along the kiln bed. The combustion process was considered to be a two-step stoichiometric reaction for primary air mixed with CH4 gas in the combustion chamber. The mixing-controlled eddy-dissipation model (EDM) was employed to predict the conversion rates of CH4, O2, CO2, and CO. The results of the prediction show that reverse flows occur near the entrance of the first combustion chamber (FCC) and the turning point at the entrance to the second combustion chamber (SCC). Temperature and species are nonuniform and are vertically stratified. Meanwhile, additional mixing in the SCC enhances postflame oxidation. A combustion efficiency of up to 99.96% can be achieved at approximately 150% excess air and 20-30% secondary air. Reasonable agreement is achieved between numerical predictions and in situ measurements.     

Polymeric carbon nitride-based photocatalysts for the removal of nitrogen oxides: a review

Environmental Chemistry Letters - Air pollution in Chinese megacities by particulate matter and ozone is a major health problem originating partly from emissions of nitrogen oxides. Therefore,...     

Effects of ellagic acid on arylamine N‐acetyltransferase activity in human colon tumor cells

The inhibition of arylamine N‐acetyltransferase (NAT) activity by ellagic acid was determined in a human colon tumor (adenocarcinoma) cell line. Two assay systems were performed, one with cellular cytosols (9000g supernatant), the other with intact colon tumor cell suspensions. The NAT activity in a human colon tumor cell line was inhibited by ellagic acid in a dose‐dependent manner in both types of examined systems: i.e. the greater the concentration of ellagic acid in the reaction, the greater the inhibition of NAT activities in both systems. The data also indicated that ellagic acid decreased the apparent K _m and V _max of NAT enzymes from human colon tumor cells in both the systems examined. This report is the first demonstration which showed ellagic acid affect human colon tumor cell NAT activity.     

Thermal Properties and Biodegradability Studies of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)

For investigating the relationship between thermal properties and biodegradability of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), several films of PHBV containing different polyhydroxyvalerate (HV) fractions were subjected to degradation in different conditions for up to 49 days. Differential scanning calorimetry (DSC), thermogravimetry (TG), specimen weight loss and scanning electron microscopy (SEM) were performed to characterize the thermal properties and enzymatic biodegradability of PHBV. The experimental results suggest that the degradation rates of PHBV films increase with decreasing crystallinity; the degradability of PHBV occurring from the surface is very significant under enzymatic hydrolysis; the crystallinity of PHBV decreased with the increase of HV fraction in PHBV; and no decrease in molecular weight was observed in the partially-degraded polymer.     

Independent factors associated with bicycle helmet use in a Korean population: A cross-sectional study

Objective: Although identification of factors that influence helmet use during bicycle riding is necessary for the selection of groups that require safe cycling education, limited baseline data are available. The aim of the present study was to analyze the rate of helmet use and the demographic factors that were independently associated with helmet use among Korean bicycle riders.

Methods: In this cross-sectional study, we used public data from the Sixth Korean National Health and Nutrition Examination Survey conducted in 2013 and 2014. Helmet users were defined as subjects who always, usually, or frequently wore helmets when cycling. Independent factors associated with helmet use were determined using odds ratios (ORss) adjusted for 5 demographic factors via multivariate logistic regression analysis.

Results: In the total population, 4,103 individuals were bicycle riders; among these, 782 individuals (19.1%) wore helmets. A total of 21.1% of male riders used helmets, compared to 15.5% of female riders (P <.001). The adjusted logistic regression model revealed that female sex (OR = 0.665; 95% confidence interval [CI], 0.554–0.797), teenage status (OR = 0.475, 95% CI, 0.333–0.678), and low household income (OR = 0.657, 95% CI 0.513–0.841) were significantly associated with nonuse of helmets.

Conclusions: Female sex, teenage status, and low household income were independent factors associated with the nonuse of helmets. We identified factors associated with helmet use during bicycle riding through analysis of baseline data on helmet usage.     

Seasonal evaluation of bioaerosols from indoor air of residential apartments within the metropolitan area in South Korea

The aims of the present study were to determine the levels of bioaerosols including airborne culturable bacteria (total suspended bacteria, Gram-positive bacteria, Staphylococcus, Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), and Gram-negative bacteria), fungi, endotoxin, and viruses (influenza A, influenza B, respiratory syncytial virus types A/B, parainfluenza virus types 1/2/3, metapnemovirus, and adenovirus) and their seasonal variations in indoor air of residential apartments. Of the total suspended bacteria cultured in an indoor environment, Staphylococcus was dominant and occupied 49.0 to 61.3 % of indoor air. Among Staphylococcus, S. aureus were detected in 100 % of households' indoor air ranging from 4 to 140 CFU/m³, and 66 % of households were positive for MRSA ranging from 2 to 80 CFU/m³. Staphylococcus and S. aureus concentrations correlated with indoor temperature (adjusted β: 0.4440 and 0.403, p?<?0.0001). Among respiratory viruses, adenovirus was detected in 14 (14 %) samples and influenza A virus was detected in 3 (3 %) samples regarding the indoor air of apartments. Adenovirus concentrations were generally higher in winter (mean concentration was 2,106 copies/m³) than in spring (mean concentration was 173 copies/m³), with concentrations ranging between 12 and 560 copies/m³. Also, a strong negative correlation between adenovirus concentrations and relative humidity in indoor air was observed (r?=??0.808, p?<?0.01). Furthermore, temperature also negatively correlated with adenovirus concentrations (r?=??0.559, p?<?0.05).     

Effect of tris-(2-chloroethyl)-phosphate (TCEP) at environmental concentration on the levels of cell cycle regulatory protein expression in primary cultured rabbit renal proximal tubule cells

Tris-(2-chloroethyl)-phosphate (TCEP) is a typical organophosphate flame retardant and has been designated as a micropollutant in aquatic environment. However, the potential effect of TCEP at environmental concentration is mostly unknown. Thus, the purpose of this study was to investigate the renal effect of TCEP at environmental concentration using primary cultured rabbit renal proximal tubule cells (PTCs). The results showed that TCEP at 10 mg L(-1) decreased cell viability, 84.2% of the control, but increased lactate dehydrogenase, 150% fold of the control. TCEP at 10 mg L(-1) also inhibited expression of CDK4, cyclin D1, CDK2, and cyclin E (79.3%, 77.7%, 73.3%, and 67.8% of the control, respectively), but increased expression of p21(WAF/Cip1) and p27(Kip1) (167.7% and 141.3% of the control, respectively). TCEP decreased DNA synthesis and cell number, 77% and 70% of the control, respectively. Through study of cell viability, cell damage, cell cycle regulator expression, DNA synthesis and cell number, TCEP at 10 microg L(-1) only affected the cells that TCEP increased expression of p21(WAF/Cip1) and p27(Kip1), 118.6% and 121.5% of the control, respectively, but decreased DNA synthesis, 91.5% of the control. In conclusion, TCEP at 10 microg L(-1) significantly increased cell cycle regulatory protein expression (p21(WAF/Cip1) and p27(Kip1)), but slightly decreased DNA synthesis in primary cultured rabbit renal PTCs.