Exacerbation of Fatality Rates Induced by Poor Air Quality Due to Open-Air Mass Funeral Pyre Cremation during the Second Wave of COVID-19.

This study investigates the air pollution-induced mortality rate during the second wave of COVID-19, which claimed several thousand lives in the capital city of India, New Delhi, even during a lockdown period. Delhi is a hotspot of unhealthy air quality. During the second wave of COVID-19 in 2021, surface ozone levels were observed to be higher, which had a direct impact on lung function, thereby making people more susceptible to COVID-19. The correlation coefficient between surface ozone concentration and mortality has been observed to be 0.74 at a 95% confidence level. This work focuses on the plausible impact and feedback of poor air quality induced by the burning of open-air funeral pyres due to the increased COVID-19 mortality rate in New Delhi, estimated by using an epidemiological model (AirQ+) of the World Health Organization. The mortality rate estimated quantitatively with the aid of AirQ+ is 1.27 excess deaths per 100,000 population due to surface ozone from pyre burning. The findings suggest transformational system goals before the resurgence of a subsequent wave.

Air quality improvement during triple-lockdown in the coastal city of Kannur, Kerala to combat Covid-19 transmission.

The novel SARS-CoV-2 coronavirus that emerged in the city of Wuhan, China, last year has since become the COVID-19 pandemic across all continents. To restrict the spread of the virus pandemic, the Government of India imposed a lockdown from 25 March 2020. In India, Kannur district was identified as the first "hotspot" of virus transmission and a "triple-lockdown" was implemented for a span of twenty days from 20 April 2020. This article highlights the variations of surface O3, NO, NO2, CO, SO2, NH3, VOC's, PM10, PM2.5 and meteorological parameters at the time of pre-lockdown, lockdown and triple-lockdown days at Kannur town in south India using ground-based analyzers. From pre-lockdown days to triple-lockdown days, surface O3 concentration was found to increase by 22% in this VOC limited environment. NO and NO2 concentrations were decreased by 61% and 71% respectively. The concentration of PM10 and PM2.5 were observed to decline significantly by 61% and 53% respectively. Reduction in PM10 during lockdown and triple-lockdown days enhanced the intensity of solar radiation reaching the lower troposphere, and increased air temperature and reduced the relative humidity. Owing to this, surface O3 production over Kannur was found to have increased during triple-lockdown days. The concentration of CO (67%), VOCs (61%), SO2 (62%) and NH3 (16%) were found to decrease significantly from pre-lockdown days to triple-lockdown days. The air quality index revealed that the air quality at the observational site was clean during the lockdown.

Potential link between compromised air quality and transmission of the novel corona virus (SARS-CoV-2) in affected areas.

The emergence of a novel human corona virus disease (COVID-19) has been declared as a pandemic by the World Health Organization. One of the mechanisms of airborne transmission of the severe acute respiratory syndrome - corona virus (SARS-CoV-2) amid humans is through direct ejection of droplets via sneezing, coughing and vocalizing. Nevertheless, there are ample evidences of the persistence of infectious viruses on inanimate surfaces for several hours to a few days. Through a critical review of the current literature and a preliminary analysis of the link between SARS-CoV-2 transmission and air pollution in the affected regions, we offer a perspective that polluted environment could enhance the transmission rate of such deadly viruses under moderate-to-high humidity conditions. The aqueous atmospheric aerosols offer a conducive surface for adsorption/absorption of organic molecules and viruses onto them, facilitating a pathway for higher rate of transmission under favourable environmental conditions. This mechanism partially explains the role of polluted air besides the exacerbation of chronic respiratory diseases in the rapid transmission of the virus amongst the public. Hence, it is stressed that more ambitious policies towards a cleaner environment are required globally to nip in the bud what could be the seeds of a fatal outbreak such as COVID-19.

Oil-material fractionation in Gulf deep water horizontal intrusion layer: Field data analysis with chemodynamic fate model for Macondo 252 oil spill.

Among the discoveries of the Deepwater Horizon blowout was the so-called "sub-surface plume"; herein termed the "oil-trapping layer". Hydrocarbons were found positioned at ~1100-1300m with thickness ~100-150m and moving horizontally to the SW in a vertically stratified layer at the junction of the cold abyssal water and the permanent thermocline. This study focuses on its formation process and fate of the hydrocarbons within. The originality of this work to the field is two-fold, first it provides a conceptual framework which places layer origin in the context of a horizontal "intrusion" from the near-field, vertical, blow-out plume and second, it offers a theoretical model for the hydrocarbon chemicals within the horizontal layer as it moves far-afield. The model quantifies the oil-material fractionation process for the soluble and fine particle. The classical Box model, retrofitted with an internal gradient, the "G-Box", allows an approach that includes turbulent eddy diffusion coupled with droplet rise velocity and reactive decay to produce a simple, explicit, transparent, algebraic model with few parameters for the fate of the individual fractions. Computations show the soluble and smallest liquid droplets moving very slowly vertically through the layer appearing within the trapping layer at low concentration with high persistence. The larger droplets move-through this trapping zone quickly, attain high concentrations, and eventually form the sea surface slick. It impacts the field of oil spill engineering science by providing the conceptual idea and the algorithms for projecting the quantities and fractions of oil-material in a deep water, horizontal marine current being dispersed and moving far afield. In the field of oil spill modeling this work extends the current generation near-field plume source models to the far-field. The theory portrays the layer as an efficient oil-material trap. The model-forecasted concentration profiles for alkanes and aromatics against the available field data support the proposed theory and the resulting model.

Air quality during demolition and recovery activities in post-Katrina New Orleans.

Air samples were collected during demolition and cleanup operations in the Lakeview district of New Orleans, Louisiana, USA, in late 2005 during the period immediately after Hurricane Katrina. Three different high-volume air samples were collected around waste collection areas that were created to temporarily hold the debris from the cleanup of residential properties in the area. Particulate concentrations were elevated and included crystalline fibers associated with asbestos. Metal concentrations on particulate matter resembled those measured in sediments deposited by floodwaters with the exception of Ba, which was elevated at all three locations. The highest organic contaminant concentration measured on particulates was the pesticide Ziram (Zinc, bis[diethylcarbamodithioato-S,S']-, [T-4]-) at 2,200 microg/g of particulate matter during sampling period 2. Ziram is used in latex paint, adhesives, caulking, and wallboard as a preservative. Fungal isolates developed from particulate air samples included species associated with disease including Aspergillus and Penicillium species. These data represent the most comprehensive assessment of demolition activities during the period immediately after Hurricane Katrina.

A numerical study on the coalescence of emulsion droplets in a constricted capillary tube.

Using a new computational model, we have studied the dynamics and coalescence of a pair of two-dimensional droplets in pressure-driven flow through a constricted capillary tube, which is a prototype problem for the analysis of the interaction of emulsion droplets in porous media. We present simulations that quantify the effects of various system parameters on the droplet stability. These include the capillary number, the interfacial tension, the suspended-to-suspending-phase viscosity ratio, the valence and concentration of added electrolytes, the droplet-to-pore-size ratio, the pore-body-to-throat-size ratio, and the type of pore geometry. Our simulations show that the capillary number Ca plays an important role in determining whether the drops coalesce. At low Ca, drops deform only slightly and coalescence occurs at the entrance of the pore throat, whereas significant deformation enables the drops move through the pore without coalescence at high Ca. Coalescence is favored at intermediate values of the viscosity ratio. The destabilizing effect of added electrolytes is found to be insignificant for 10-mum drops, but significant for micron-size drops. Among the geometric-related parameters, the drop-to-pore-size ratio is the most significant.

Chemical and microbiological parameters in New Orleans floodwater following Hurricane Katrina.

Hurricane Katrina, rated as a Category 4 hurricane on the Saffir-Simpson scale, made landfall on the U.S. Gulf Coast near New Orleans, Louisiana on Monday, August 29, 2005. The storm brought heavy winds and rain to the city, and several levees intended to protect New Orleans from the water of Lake Pontchartrain were breached. Consequently, up to 80% of the city was flooded with water reaching depths in excess of three meters in some locations. Research described in this paper was conducted to provide an initial assessment of contaminants present in floodwaters shortly after the storm and to characterize water pumped out of the city into Lake Pontchartrain once dewatering operations began several days after the storm. Data are presented which demonstrate that during the weeks following the storm, floodwater was brackish and well-buffered with very low concentrations of volatile and semivolatile organic pollutants. Dissolved oxygen was depleted in surface floodwater, averaging 1.6 mg/L in the Lakeview district and 4.8 mg/L in the Mid-City district. Dissolved oxygen was absent (< 0.02 mg/L) at the bottom of the floodwater column in the Mid-City district 9 days afterthe storm. Chemical oxygen demand (Mid-City average = 79.9 mg/L) and fecal coliform bacteria (Mid-City average = 1.4 x 10(5) MPN/100 mL) were elevated in surface floodwater but typical of stormwater runoff in the region. Lead, arsenic, and in some cases, chromium, exceeded drinking water standards but with the exception of some elevated Pb concentrations generally were typical of stormwater. Data suggest that what distinguishes Hurricane Katrina floodwater is the large volume and the human exposure to these pollutants that accompanied the flood, rather than very elevated concentrations of toxic pollutants.

Monitoring of fogwater chemistry in the gulf coast urban industrial corridor: Baton Rouge (louisiana).

Seventeen fog events were sampled in Baton Rouge, Louisiana during 2002-2004 as part of characterizing wet deposition by fogwater in the heavily industrialized corridor along the Louisiana Gulf Coast in the United States. These samples were analyzed for chemical characteristics such as pH, conductivity, total organic and inorganic carbon, total metals and the principal ion concentrations. The dominant ionic species in all samples were NH4+, NO3-, Cl- and SO4(2-). The pH of the fogwater sampled had a mean value of 6.7 with two cases of acidic pH of 4.7. Rainwater and fogwater pH were similar in this region. The acidity of fogwater was a result of NO3- but partly offset by high NH4+. The measured gaseous SO2 accounted for a small percentage of the observed sulfate concentration, indicating additional gas-to-particle conversion of SO2 to sulfate in fogwater. The gaseous NOx accounted for most of the dissolved nitrate and nitrite concentration in fogwater. The high chloride concentration was attributable to the degradation of chlorinated organics in the atmosphere. The metal composition was traced directly to soil-derived aerosol precursors in the air. The major metals observed in fogwater were Na, K, Ca, Fe, Al, Mg and Zn. Of these Na, K, Ca and Mg were predominant with mean concentrations > 100 microM. Al, Fe and Zn were present in the samples, at mean concentrations < 100 microM. Small concentrations of Mn (7.8 microM), Cu (2 microM), Pb (0.07 microM) and As (0.32 microM) were also observed in the fogwaters, and these were shown to result from particulates (PM2.5) in the atmosphere. The contribution to both ions and metals from the marine sources in the Louisiana Gulf Coast was minimal. The concentrations of all principal ionic species and metals in fogwater were 1-2 orders of magnitude larger than in rainwater. Several linear alkane organic compounds were observed in the fogwater, representing the contributions from petroleum products at concentrations far exceeding their aqueous solubility. A pesticide (atrazine) was also observed in fogwater, representing the contribution from the agricultural activities nearby.

Soil-water partitioning and desorption hysteresis of volatile organic compounds from a Louisiana Superfund site soil.

The adsorption and desorption of three volatile organic compounds (1,2-dichloroethane, 1,1,2- trichloroethane and 1,1,2,2-tetrachloroethane) from a previously uncontaminated clayey soil sample from a Superfund site in North Baton Rouge, Louisiana was studied. In the linear range of the adsorption isotherm, the partition constants were not affected by the presence of the co-solutes. The adsorption isotherms over a wide concentration range on the soil followed the nonlinear Freundlich isotherm. The desorption of the compounds showed significant hysteresis at all concentrations studied. Approximately 20 to 70% of the adsorbed mass of organic compounds resisted the desorption even after five months of successive desorption steps. The desorption of four compounds (1,2-dichloroethane, 1,1,2-trichloroethane, 1,4-dichlorobenzene and hexachlorobutadiene) from a contaminated soil sample from the same site was also studied. The aqueous concentration declined as the successive desorption steps progressed. For hexachlorobutediene the desorption can be visualized as occurring in two stages. The first stage involved a 'loosely bound' or 'reversible' fraction and the second stage involved a 'tightly bound' or 'resistant' fraction.

Rate-limited desorption of volatile organic compounds from soils and implications for the remediation of a Louisiana Superfund site.

The rates of desorption of trichloroethylene (TCE) and 1,3-dichlorobenzene (DCB) from a silty soil at a Superfund site and a silty-clayey soil from an uncontaminated bottomland hardwood swamp in Baton Rouge, Louisiana were studied in laboratory batch systems. The effect of the age of soil contamination was studied using a laboratory-spiked soil incubated for 3 days, 3 months and 5 months. An empirical non-linear model was used to describe the bi-phasic nature of desorption with one fraction (labile) being released in relatively short periods of time (typically 24-100 hr) and a second fraction (non-labile or irreversible) being resistant to desorption. The non-linear model parameters, viz., the fraction of the chemical released rapidly (F), and the first order desorption rate coefficients, k1 and k2 respectively for the labile and slowly released fractions were determined by fitting the experimental data to the model. The data fit the model well as indicated by the high r2 values. The estimate of k1 was good. However, the values of k2 are known with less precision due to the limited duration of the experiment and number of samples taken at long times. In addition, desorption kinetics of 3 and 5-month old contaminated soils showed that progressively less amount of contaminant was available for facile desorption (lower F) compared to freshly contaminated soil. The labile fraction had desorption rate constants of the order of 10(-1) h(-1), whereas the slowly released fraction had rate constants of the order of 10(-4) h(-1) in accord with literature reported values for a variety of other compounds and soils. Possible mechanisms describing these rates and implications for the site clean up are discussed.

Air-water partition constants for volatile methyl siloxanes.

Silicones are an important class of hydrophobic compounds in widespread use. To evaluate their fate in the environment, an accurate value of the air-water partition (Henry's law) constant is necessary, which, unfortunately, is lacking at present. A static head space and a newly developed dynamic vapor entry loop method were used to obtain the air-water partition constant for six volatile methyl siloxanes. Internally consistent data were obtained. The value of Henry's constant, as calculated from pure component vapor pressure and aqueous solubility, was 10- to 170-fold greater than the experimental values. A correction to the Henry's constant that involves the ratio of the thermodynamic activity coefficient for a methyl siloxane at infinite dilution to that at saturation solubility in the aqueous phase is proposed.

Testing a multimedia compartmental model with monitoring data.

Based on its geographic similarity and nested structure, a chemical transport and transformation model developed in The Netherlands was adopted to a nine-parish, 5,400-km2 area in southern Louisiana, USA, and tested for its ability to predict concentrations in the environment. SimpleBox 2.0 represents a class of models that compartmentalize the air, water, soil, sediment, and plants into boxes while maintaining a high degree of detail for processes within and between boxes. Past use has been in the evaluative mode, primarily where qualitative predictions of chemical behavior and distribution are made. Limited testing of model-predicted versus measured concentrations have been attempted. In recent years, quality and quantity of emission and monitoring data have improved dramatically. Such information was used in calibration and validation exercises with eight chemicals in the Louisiana chemical corridor, which receives inputs from urban, industrial, and agricultural sources. Geographically, the corridor was nested within the state of Louisiana, which was in turn nested within the continental United States. Parameter sensitivity studies, including transport coefficients, temperature, and degradation half-life revealed that the latter produces the largest range of variation in predicted concentrations. Published half-life data were used with benzene, vinyl chloride, 1,1,1-trichloethane, and atrazine in a calibration phase with 1995 monitoring data at steady state; this allowed selection of the appropriate emission database. A validation exercise was performed with toluene, styrene, trichloroethylene, and metribuzin. Predictions were compared to average measured concentrations. Atrazine and metribuzin reside primarily in the water; the others reside in the air. The predicted concentrations for benzene, metribuzin, and trichloroethylene were low by a factor of less than two. Vinylchloride, toluene, and 1,1,1-trichloroethane were low by factors between 3 and 10. Styrene and atrazine were low by factors of 45 and 65, respectively.

Air emission flux from contaminated dredged materials stored in a pilot-scale confined disposal facility.

A pilot-scale field simulation was conducted to estimate the air emissions from contaminated dredged material stored in a confined disposal facility (CDF). Contaminated dredged material with a variety of organic chemicals, obtained from Indiana Harbor Canal, was used in the study. It was placed in an outdoor CDF simulator (i.e., a lysimeter of dimensions 4 ft x 4 ft x 2 ft). A portable, dynamic flux chamber was used to periodically measure emissions of various polynuclear aromatic hydrocarbons (PAHs). A weather station was set up to monitor and record the meteorological conditions during the experiment. The fluxes of several PAHs were monitored over time for 6 1/2 months. Initial 6-hr average fluxes varied from 2 to 20 ng/cm2/hr for six different PAHs. The flux values declined rapidly for all compounds soon after placement of the dredged material in the CDE Chemical concentrations derived from flux values were generally of low magnitude compared with ambient standards. Data obtained from the experiment were compared against those predicted using models for air emissions. Model simulations showed that initially the flux was largely from exposed pore water from saturated (wet) sediment, whereas the long-term flux was controlled by diffusion through the pore air of the unsaturated sediment. Model predictions generally overestimated the measured emissions. A rainfall event was simulated, and the dredged material was reworked to simulate that typical of a CDF operation. Increased flux was observed upon reworking the dredged material.

Solvent sublation for waste minimization in a process water stream - a pilot-scale study.

Solvent sublation, an adsorptive bubble separation process, was carried out on a pilot scale to separate dilute concentrations (30-100ppmw) of naphthalene from a process water stream at a temperature of 140 degrees F. The test was conducted at the Borden Chemicals and Plastics (BCP) acetylene plant site located in Geismar, Louisiana. A carbon steel column of 6" i.d. and 17' high was constructed. White mineral oil supplied by Texaco Inc., was used as the organic solvent for solvent sublation. A special annular shear sparger was used for nitrogen gas sparging into the vessel. The process was conducted in two-phase continuous and three-phase continuous modes. The naphthalene recovery from the process water was independent of the oil flow rate, but depended on the nitrogen-to-water flow rate ratio. The release of naphthalene to the overhead gas space during the solvent sublation process was substantially less than that during conventional gas stripping. The improved performance of solvent sublation over both conventional gas stripping and solvent extraction operations was apparent.

Sediment-air equilibrium partitioning of semi-volatile hydrophobic organic compounds. Part 1. Method development and water vapor sorption isotherm.

Contaminated sediments that become exposed to air as a result of dredging and disposal in confined disposal facilities are potential sources of air pollution. A critical parameter to develop emission estimation models is the equilibrium partition coefficient of contaminants, between sediment and air. In this first of two articles, we present a method, based on gas saturation in a flowing stream, to study both the adsorption of water and semi-volatile organic compounds on a sediment from the Campus Lake, Baton Rouge, LA, USA. The experimental set-up was used to determine the adsorption isotherm for water partitioning between sediment and pore-air. A detailed characterization of the sediment surface area and pore volume was used to develop an adsorption-condensation model for predicting water sorption on sediment. The model was used to estimate the importance of water adsorption on mineral surfaces and condensation in pores. This information serves, in the accompanying second article in the series, as the basis for the modeling of the partitioning of phenanthrene, and dibenzofuran.

Sediment-air equilibrium partitioning of semi-volatile hydrophobic organic compounds part 2. Saturated vapor pressures, and the effects of sediment moisture content and temperature on the partitioning of polyaromatic hydrocarbons.

A gas saturation methodology was used to determine the sediment/air partition coefficient (K(SA)) for phenanthrene and dibenzofuran on a local sediment from the Campus Lake, Baton Rouge. The effects of sediment moisture content, air relative humidity and temperature on K(SA) for phenanthrene were ascertained. The saturated vapor pressures of the compounds were also measured. The sediment moisture content had a striking effect on K(SA); increasing sediment moisture content decreased K(SA). Temperature also had a dramatic effect on K(SA). The variation with temperature was used to evaluate the heats of adsorption on both 'dry' (< 0.8% by mass of water) and 'wet' (> 6% by mass of water) sediments. The heat of adsorption for phenanthrene normalized to unit molecular surface area indicated for the physically adsorbed organic compound was seven times smaller than that for a water molecule. The experimental value of K(SA) was used to test a proposed theoretical model. A good agreement was observed for both phenanthrene and dibenzofuran. The model can be extended to other compounds and sediment types for prediction of air emissions from exposed sediment and dredged materials.