Air Contaminants Research Articles

Seasonal Assessment of particulate matter (PM2.5) and its contribution towards mortality in Lahore city, Pakistan

Air pollution is one of the several environmental problems urbanization brings. One of the air contaminants that impacts human health is particulate matter (PM). The current study aimed to assess the relative risks and attributable proportions. It can be brought on by human exposure to PM2.5 and PM10 (PM with aerodynamic diameters ≤ 2.5 μm and ≤ 10 μm, respectively). AirQ+ software was used to modify the health effects of particles on human beings in terms of attributable percentage (AP). Environmental Protection Department (EPD), Punjab Bureau of Statistics, and Punjab Health Department provided input data on particulate concentration, health, and population. Findings indicated that PM2.5 with an average concentration of 106 ug/m3 per year makes up 54.04 % of the attributable proportion (AP) of age 30+ adults, all-cause mortality rate, and 46.31% AP of age 30+ adults with chronic obstructive pulmonary disease (COPD). AP to stroke mortality in adults age 25+ was 65.01% (BI-150), and 38.28% (BI-630) was in children aged 0-5 years, contributing to acute lower respiratory infection (ALRI) mortality. The attributable proportion to ischemic heart diseases (IHD) in adults age 25+ was found to be 56.19%. It was also found that PM10 with an average concentration of 163 ug/m3 contributes 44.05% AP to infant post-neonatal. There must be appropriate mitigating strategies for pollution reduction concentration to reduce the potential adverse effects of air on health particulates.

Highly efficient photocatalytic degradation of hazardous organic and inorganic contaminants by heterogeneous nZVI-doped Al2ZnTiO6 double perovskite/g-C3N4 photocatalyst under visible light irradiation

Among the hazardous organic and inorganic pollutants, organic dyes, nitrate (NO3-), carbon dioxide (CO2), and toxic heavy metals (THMs) are four types of hazardous contaminants that have become a serious global problem. Recently, perovskite photocatalysts have shown high efficiency in removing water and air contaminants. In this research, zero-valent iron nanoparticles (nZVI)- doped Al2ZnTiO6 (AZTO) double perovskite/graphitic carbon nitride (g-C3N4(gCN)) nanocomposite (NC) was firstly synthesized by the sol-gel method as a new high-efficiency perovskite photocatalyst. Also, the influence of the main factors such as solution pH, reaction time, photocatalyst dosage, and contaminants concentration on the photocatalytic performance of the nZVI-doped Al2ZnTiO9/g-C3N4 nanocomposite was evaluated. Due to the unique features of the nZVI-doped Al2ZnTiO6/g-C3N4 structure and suitable band gap position, which is suitable for the efficient migration e-/h+ charges dissociation and the enhancement of photocatalytic activity, this nanocomposite showed effective performance to the elimination of methyl orange (MO) anion, and methylene blue (MB) cation dye, NO3-, CO2, and THMs contaminants. The UV–visible spectra showed the elimination efficiency of 88%, 87%, 80%, 72%, and 90% for methyl orange anion dye, methylene blue cation dye, nitrate, carbon dioxide, and toxic heavy metals in optimal experiment conditions, respectively. Also, IEC and GC analysis showed an efficiency of 60% for the photoconversion of nitrate to harmless nitrogen gas (N2) and 42% for the photoconversion efficiency of CO2 to Methane (CH4) gas fuel. Eventually, the nZVI-doped Al2ZnTiO6/g-C3N4 nanocomposite displayed good recyclability and high photocatalytic activity compared to recently synthesized photocatalysts by testing its photocatalytic property after five repetitions.

Environmental gaseous pollutants are related to increase of acute coronary syndrome in Valencia region, Spain

Introduction and aimsEnvironmental pollution are one of the most relevant risk factors to atherosclerosis. To know awareness about the importance of urban air pollution as a trigger for hospital admission due to acute coronary syndrome (ACS), this study analyzed levels of different gaseous air pollutants in the air and its correlation with number of ACS. MethodsEpidemiological data of patients admitted for ACS in five towns during the years 2006–2008 were recovered. Clinical data regarding admissions for ACS were obtained from the hospital admission services. Measures of seven air contaminants were recovered from the environmental stations. Mixed model including sex, age, location, and the average levels of air pollutants contaminants as fixed effects and its interaction were performed. ResultsThe incidence rate of ACS is higher in man than woman, and higher in older people than young. The maximum ACS were in the last trimester of the year, was the most elevated levels of gaseous pollutants have been found. Levels of NO2, NO, and CO are positively correlated between them, and negatively correlated with O3 levels. All air pollutants analyzed increase the number of ACS hospital admission in the five locations evaluated. ConclusionsLevels of gaseous pollutants are related between them, being the levels of NO2, NO, and CO, positively correlated, and negatively correlated with levels of O3. Number of ACS hospital admission increases with levels of five air gaseous pollutants studied.

Nanotools of ZnO Nanostructures offered by Nanotechnology for Sustainable Farming

Abstract: The field of nanotechnology has been growing immensely having its application in health, automobile, defence and agriculture sectors. Recently in a decade its role has been explored and analysed in agriculture sector to comply the demanding needs of food with increasing population. This can be achieved by enhancing crop yield, maintaining air, water and soil quality, managing the resources and harvested food. Nanosensors can help in attaining them with high efficacy and specificity. They allow precise monitoring of plant growth with efficient use of resources, and provide timely detection of plant diseases, air and soil contamination by keeping check on pathogens. By using internet and computer technology the data can be collected and assessed to take corrective and curative measures instantly, allowing good management. Here we discuss ZnO based nanostructures, their cost effective methods of synthesis, role as nutrient source, nanosensors to keep check on pathogens, contaminants in air, water, pesticide and moisture of soil. By proper care and monitoring of crops on real time basis and keeping agro-ecosystem safe with cost effective nanotools, we shall achieve a boost in crop productivity.

Selection of statistical technique for imputation of single site-univariate and multisite-multivariate methods for particulate pollutants time series data with long gaps and high missing percentage.

Monitoring air contaminants has become essential to exposure science, toxicology, and public health research. However, missing values are common while monitoring air contaminants, especially in resource-constrained settings such as power cuts, calibration, and sensor failure. In contaminants monitoring, evaluating existing imputation techniques for dealing with recurrent periods of missing and unobserved data are limited. The proposed study aims to perform a statistical evaluation of six univariate and four multivariate time series imputation methods. The univariate methods are based on inter-time correlation characteristics, and the multivariate approach considers muti-site to impute missing data. The present study retrieved data from 38 ground-based monitoring stations for particulate pollutants in Delhi for 4 years. For univariate methods, missing values were simulated under 0-20% (5%, 10%, 15%, and 20%), and high 40%, 60%, and 80% missing levels having long gaps. Before evaluating multivariate methods, input data underwent pre-processing steps: selecting the target station to be imputed, choosing covariates based on the spatial correlation between multiple sites, and framing a combination of target and neighbouring stations (covariates) under 20%, 40%, 60%, and 80%. Next, the particulate pollutants data of 1480 days is provided as input to four multivariate techniques. Finally, the performance of each algorithm was evaluated using error metrics. The results show that the long interval time series data and spatial correlation of multiple stations significantly improved outcomes for univariate and multivariate time series methods. The univariate Kalman_arima performs well for long-missing gaps and all missing levels (except for 60-80%), yielding low error and high R2 and d values. In contrast, multivariate MIPCA performed better than Kalman-arima for all target stations with the highest missing percentage.

Micro‐ to macro‐scaling analysis of PM2.5 in sensitive environment of Himalaya, India

Fine particulate matter (PM) in the atmosphere has become a significant air contaminant with substantial health consequences. Although airborne remote sensing and ground sensor monitoring can offer air quality datasets containing PM2.5, there are limitations to effectively analysing large long‐term datasets. The research aims to evaluate air quality over the Himalayan region using the multifractal approach for the PM2.5 data time series. Fractal dimension (FD), Hurtz exponent (H), and predictability (PI) are estimated using the rescaled range. PM2.5 is found to have high concentration and frequency throughout the day. The same is found in the night hours during peak tourism months. The hourly PM2.5 time series datasets have shown multifractality. The primary reason for this is emissions produced by vehicles and anthropocentric activities in the region. The H is used to assess the dynamic features of the PM2.5 time series in terms of persistence and self‐correlation. In the context of climate change studies, it is crucial to monitor the spatial distribution and dynamic behaviour of PM2.5 in the Himalayan foothills. This study aims to provide prediction analyses and air quality index (AQI) estimates and demonstrate how PM2.5 concentrations alter the sensitive environment throughout the micro to macro scale. This will help us to build a long‐term strategy for reducing the harmful effect of increasing pollution levels on the ecosystem and human health.

Spatio-temporal patterns and trends of the air pollution integrating MERRA-2 and in situ air quality data over Egypt (2013–2021)

For best-informed decision-making to improve climate change adaptation and reduce present and future air pollution health hazards, it is essential to identify major trends in spatiotemporal air quality patterns of common air contaminants. This study examined the patterns and trends of SO2, NO2, CO, O3, and particulate matter (PM) air pollutants over 91 monitoring stations in Egypt during 93 months in the August (2013)–April (2021) period. In situ data with their monthly, seasonal, and yearly spatial trends are defined and used to validate the counterpart satellite reanalysis MERRA-2 data. The Mann–Kendall test characterized the seasonal monotonic trends and their Sen’s slope, and annual change rate for both data series. Regression analysis of MERRA-2 against in situ concentrations of SO2 and PM10 revealed underestimation with RMSE values of 13.38 g m−3 and 69.46 g m−3, respectively. Local plumes with variable magnitudes characterized distinct industrial places clarified by patterns of in situ pollutants. As a result of the COVID-19 lockdown, the in situ air pollutants showed a considerable regional decline in the yearly average in 2020 compared to the years before. The in situ air pollutants showed annual trends far more significant than those seen in the MERRA-2 data. The shortcomings of the few and spatiotemporal discontinuities of the in situ contaminants are addressed by MERRA-2 air quality products. The in situ data made trends and magnitudes clear that were hidden in their MERRA-2 counterparts. The results clarified air pollution patterns, trends, and spatial variability over Egypt that are essential for climate risk management and for reducing environmental/health concerns.

Recalibrating polyparameter linear free energy relationships and reanalyzing mechanisms for partition of nonionic organic compounds to low-density polyethylene passive sampler

Equilibrium passive sampling techniques based on the low-density polyethylene (LDPE) film are increasingly used for determining the concentration of contaminants in water and air. Reliable models capable of predicting LDPE–water and LDPE–air partition coefficients (KiLDPEw and KiLDPEa) would be very useful. In previous studies, polyparameter linear free energy relationships (PP-LFERs) based on Abraham's solute descriptors were calibrated for LDPE–water and LDPE–air systems. Unfortunately, a portion of unreliable partition coefficients and solute descriptors were included in the calibration sets of these previous studies, leading to unexpected system parameters and predictive performance in the regression results. In this study, more reliable PP-LFERs were recalibrated for LDPE–water and LDPE–air systems (20‒25 °C) using carefully collected reliable partition coefficients and solute descriptors of various polar and nonpolar compounds (over one hundred and with low redundancy) from the literature, as well as the robust regression method. The PP-LFERs performed well with root-mean-square errors of 0.15–0.25 log units and successfully predicted KiLDPEw and KiLDPEa values spanning over 10 orders of magnitude for compounds with reliable descriptors. The partitioning mechanisms of compounds to LDPE were also reanalyzed and compared in detail with n-alkanes (C6–C16). Generally, LDPE is more prone to form dispersion interactions with solutes than n-alkanes, while it is more difficult to form cavities in LDPE. In addition, the crystallinity of LDPE is not the sole reason for the distinct constant terms presenting in PP-LFERs for LDPE–water and n-hexadecane–water systems.

Update of Ambient Air Pollution Monitoring Programs within Regional-Level Implementation of National Projects

Introduction: The Federal Clean Air Project has been developed and is now implemented with the purpose of improving both ambient air quality and the quality of life of the population in 12 pilot cities, including Bratsk. An adequate air pollution control program, priority pollutant monitoring, and health risk management can facilitate improvement of the quality of human life and achievement of the targets of government projects. Objective: To update and streamline the ambient air quality monitoring program in Bratsk within implementation of national and federal projects at the regional level. Materials and methods: The updated air quality control program in Bratsk was based on the results of dispersion modeling verified by instrumental measurements of 34 pollutants at five monitoring stations of the Federal Service for Hydrometeorology and Environmental Monitoring (Roshydromet) and three stations of the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing (Rospotrebnadzor). The consolidated database included 2,202 sources emitting 112 chemicals, with total emissions approaching 127,207 tons per year. Hygienic analysis and health risk assessment were performed according to conventional procedures. Results: We established that airborne levels of 29 pollutants exceeded their maximum allowable concentrations (MAC), i.e. were up to 7.0 times higher than short-term MAC, 13.8 and 60 times higher than the average daily and annual MAC, respectively. We also found that 19 air contaminants posed unacceptable health risks for the local population (CR up to 1.82×10–3, HQac up to 113.2, HQcr up to 211.1). Cluster analysis of the results of health risk assessment allowed us to distinguish three clusters within the urban area. We substantiated cutting down the number of monitoring stations to one and its optimal location in Cluster 1, the expediency of moving the station in Cluster 2 and adding a station in Cluster 3 at the point of concern. Optimization of the air quality control program involves reducing the number of monitored pollutants to 8–15 chemicals that are not covered by Roshydromet air monitoring plan. Conclusions: Given the changing sanitary and epidemiological situation, streamlining of air quality monitoring programs will provide relevant and timely information, thus contributing to elaboration of effective health risk management activities.

In vitro neurotoxicity screening of engine oil- and hydraulic fluid-derived aircraft cabin bleed-air contamination

In most airplanes, cabin air is extracted from the turbine compressors, so-called bleed air. Bleed air can become contaminated by leakage of engine oil or hydraulic fluid and possible neurotoxic constituents, like triphenyl phosphate (TPhP) and tributyl phosphate (TBP). The aim of this study was to characterize the neurotoxic hazard of TBP and TPhP, and to compare this with the possible hazard of fumes originating from engine oils and hydraulic fluids in vitro. Effects on spontaneous neuronal activity were recorded in rat primary cortical cultures grown on microelectrode arrays following exposure for 0.5 h (acute), and 24 h and 48 h (prolonged) to TBP and TPhP (0.01–100 µM) or fume extracts (1–100 µg/mL) prepared from four selected engine oils and two hydraulic fluids by a laboratory bleed air simulator. TPhP and TBP concentration-dependently reduced neuronal activity with equal potency, particularly during acute exposure (TPhP IC50: 10–12 µM; TBP IC50: 15–18 µM). Engine oil-derived fume extracts persistently reduced neuronal activity. Hydraulic fluid-derived fume extracts showed a stronger inhibition during 0.5 h exposure, but the degree of inhibition attenuates during 48 h. Overall, fume extracts from hydraulic fluids were more potent than those from engine oils, in particular during 0.5 h exposure, although the higher toxicity is unlikely to be due only to higher levels of TBP and TPhP in hydraulic fluids. Our combined data show that bleed air contaminants originating from selected engine oils or hydraulic fluids exhibit neurotoxic hazard in vitro, with fumes derived from the selected hydraulic fluids being most potent.

Experimental Investigation of the Influence of NO on a PEM Fuel Cell System and Voltage Recovery Strategies

Air contaminants can have detrimental effects on the performance and durability of proton exchange membrane (PEM) fuel cell vehicles. This research focuses on the experimental investigation of the effect of nitrogen monoxide (NO) in the cathode gas stream, which provokes a cell voltage decrease due to the partially reversible adsorption of NO on the platinum catalyst. The concentration and exposure time of NO in the cathode gas stream are varied at selected constant current densities and load ramps to assess the effects throughout the fuel cell system operating range. The results show the cell voltage loss in the presence of NO and reveal a near-catalyst saturation with increased injected NO mass. Additionally, several voltage recovery and mitigation strategies are introduced and discussed by presenting conclusions about the general effect of NO on a fuel cell system in operation. The most promising recovery strategy for fuel cell systems is identified, and the overall system degradation is discussed. All experiments are performed in a test bed environment on a 25 kW low-temperature fuel cell system via controlled injection of NO into the cathode gas stream.

Progress and Perspective for In Situ Studies of Oxygen Reduction Reaction in Proton Exchange Membrane Fuel Cells.

Proton exchange membrane fuel cell (PEMFC) is one of the most promising energy conversion devices with high efficiency and zero emission. However, oxygen reduction reaction (ORR) at the cathode is still the dominant limiting factor for the practical development of PEMFC due to its sluggish kinetics and the vulnerability of ORR catalysts under harsh operating conditions. Thus, the development of high-performance ORR catalysts is essential and requires a better understanding of the underlying ORR mechanism and the failure mechanisms of ORR catalysts with in situ characterization techniques. This review starts with the introduction of in situ techniques that have been used in the research of the ORR processes, including the principle of the techniques, the design of the in situ cells, and the application of the techniques. Then the in situ studies of the ORR mechanism as well as the failure mechanisms of ORR catalysts in terms of Pt nanoparticle degradation, Pt oxidation, and poisoning by air contaminants are elaborated. Furthermore, the development of high-performance ORR catalysts with high activity, anti-oxidation ability, and toxic-resistance guided by the aforementioned mechanisms and other in situ studies are outlined. Finally, the prospects and challenges for in situ studies of ORR in the future are proposed.

Air phyto-cleaning by an urban meadow – Filling the winter gap

Urban areas are characterised by polluted air which endangers the health and quality of life of city dwellers. Among the dangerous air contaminants is particulate matter (PM) and one of the main sources of PM in urban areas is road traffic. Studies have already shown that the air can be phyto-cleaned by plants, especially trees and shrubs. However, for safety reasons, planting trees and shrubs in some places is problematic, e.g. close to roads. These locations are usually occupied by lawns, which are plant communities of low ecological value. Unfortunately, too little attention has been paid so far to urban meadows. Therefore, this study (i) investigated for the first time the phyto-cleaning potential of an urban meadow all year round, including autumn–winter period, and (ii) compared the efficiency and mechanisms of PM phyto-cleaning by an urban meadow and lawn during the vegetative season. Plant material was harvested from urban meadow (in June, August, November and March) and lawns (in June and August) located by a busy road in Warsaw (Poland). PM was analysed in two categories (surface PM and in-wax PM) and two size fractions (fine: 0.2–2.5 µm, coarse: 2.5–10 µm). The results obtained suggested that accumulation of PM by urban meadow is possible even out of vegetative season. In autumn and winter, even though the meadow plants were physiologically not active, they still participated in air phyto-cleaning. Urban meadow phyto-cleaned air most effectively in summer when the vegetation was fully developed, and least effectively in autumn. During the vegetative season, the urban meadow accumulated more PM than lawns, mostly due to the greater height and complex structure. Therefore, urban meadow would appear to offer an promising solution to problem of phyto-cleaning of urban air in the immediate vicinity of roads throughout the year.

Environmental gaseous pollutants are related to increase of acute coronary syndrome in Valencia region, Spain

Introduction and aimsEnvironmental pollution are one of the most relevant risk factors to atherosclerosis. To know awareness about the importance of urban air pollution as a trigger for hospital admission due to acute coronary syndrome (ACS), this study analyzed levels of different gaseous air pollutants in the air and its correlation with number of ACS. MethodsEpidemiological data of patients admitted for ACS in five towns during the years 2006–2008 were recovered. Clinical data regarding admissions for ACS were obtained from the hospital admission services. Measures of seven air contaminants were recovered from the environmental stations. Mixed model including sex, age, location, and the average levels of air pollutants contaminants as fixed effects and its interaction were performed. ResultsThe incidence rate of ACS is higher in man than woman, and higher in older people than young. The maximum ACS were in the last trimester of the year, was the most elevated levels of gaseous pollutants have been found. Levels of NO2, NO, and CO are positively correlated between them, and negatively correlated with O3 levels. All air pollutants analyzed increase the number of ACS hospital admission in the five locations evaluated. ConclusionsLevels of gaseous pollutants are related between them, being the levels of NO2, NO, and CO, positively correlated, and negatively correlated with levels of O3. Number of ACS hospital admission increases with levels of five air gaseous pollutants studied.

A preliminary assessment of the health impacts of indoor air contaminants determined using the DALY metric

Common metrics used for assessing air quality are based on guidelines and/or standards for regulating concentrations that should not be exceeded over a period. Exceeding those values would represent problematic situations. A lack of agreement on appropriate norms or standards deems this approach sub-optimal. Moreover, this approach does not relate a proportion of exceedance to specific health outcomes. A need to develop health-centered IAQ metrics that can quantify burden of disease in terms of epidemiological evidence of population morbidity and mortality supported by the best knowledge of health effects, is pressing. This work proposes an approach that harnesses the advantages of using disability adjusted life years (DALYs) as a valuable metric to quantify and rank the burden of household air pollution, as a global perspective. Two methods were used to compute DALYs, one mainly based on incidence data and another mainly based on effect factors (i.e. DALYs per unit-intake of contaminant of interest). The methods are based on the following parameters: risk estimates, baseline incidence rates, damage factors, indoor air contaminant concentrations, human toxicological & epidemiological effect factors, dose–response factors, cancer-related variables and breathing rates. Systematic searches and reviews of peer-reviewed literature (including systematic reviews and meta-analyses) were performed to find information on said input parameters. Meta-analysis was used to pooled and synthesise data from different studies. A Monte Carlo approach was used to model results in DALYs lost. Over 1000 articles were revised and overall ∼200 unique sources were used as sources of data. Ten contaminants were accounted for with specific risk estimates and damage factors data, for which human epidemiological effect factors were derived. Representative concentrations of 45 contaminants were calculated. Thirty-nine contaminants were accounted for human toxicological effect factors. Total pooled DALYs were estimated per 100,000 exposed population with corresponding uncertainty intervals. Estimated population-averaged annual cost, in DALYs lost, of chronic air contaminant inhalation in dwellings indicate that the contaminants with highest median DALY loss estimates are PM10 and PM2.5 (magnitudes of 103); PMcoarse, formaldehyde and NO2 could be found with magnitudes of 102; contaminants with magnitudes of 101 include radon and ozone, finally SO2 and acrolein would have magnitudes of 10°; mould-related bioaerosols could be of interest as well. The updated strategies allowed for the quantification of contaminants and health outcomes that were not accounted for in previous works. Computed DALYs have lower uncertainty intervals than those previously proposed. The updated methodology presented in this study may be used to assess cumulative health impacts of indoor air contaminants.

Assessment of the Reverberations Caused by Predominant Air Pollutants on Urban Vegetation: A Multi-Site Study in Varanasi Located in Indo-Gangetic Plains

Plant responses to air pollution have been extensively studied in urban environments. Nevertheless, detailed and holistic studies assessing their retaliation to air contaminants are still limited. The present study evaluates the effect of criteria pollutants (SO2, NO2, PM10 and O3) on the overall biochemistry and resource allocation strategy of plants in order to categorize the dominant roadside species (Mangifera indica, Psidium guajava, Ficus religiosa, Azadirachta indica, Dalbergia sissoo, Cascabela thevetia and Bougainvillea spectabilis) of the Indo-Gangetic Plains (IGP), with different morphologies and habits, into species that are tolerant and sensitive to the prevailing air pollutants. This study was performed at three different land-use sites (industrial, commercial and reference) in Varanasi for two seasons (summer and winter). It was inferred that NO2 and PM10 consistently violated the air quality standards at all the sites. The fifteen assessed parameters reflected significant variations depending upon the site, season and plant species whereupon the enzymatic antioxidants (superoxide dismutase and catalase) and resource utilization parameters (leaf area and leaf dry matter content) were remarkably affected. Based on the studied parameters, it was entrenched that deciduous tree species with compound leaves (D. sissoo > A. indica) were identified as the less sensitive, followed by a shrub (C. thevetia > B. spectabilis), while evergreen species with simple leaves were the most sensitive. It was also substantiated that the morphology of the foliage contributed more toward the differential response of the plants to air pollutants than its habit.

80 The Need for a Clinical and Translational Science Framework to Bridge Environmental Contamination Data and Male Reproductive Health

OBJECTIVES/GOALS: Although there is ample evidence that environmental contaminants impact reproductive health, the exact mechanisms of action, for the most part, remains unclear. We sought to determine whether known contaminants in Puerto Rico can contribute to the selection of a bioassay to add granularity to geospatial contamination data at the cellular level. METHODS/STUDY POPULATION: A PubMed literature search was conducted: Puerto Rico AND Vieques AND Environmental Contaminants AND Heavy Metals OR Phthalates OR Metals OR PCB OR Air Pollution OR CVOC . Additional inclusion criteria were free full text, English language and year of publication between 2000 to 2022 (n = 244 studies). References that were not related to Puerto Rico and environmental contaminants in air, soil, water, or vegetation were excluded. A second PubMed literature search was conducted to determine whether a clinical link has been established between contaminant exposure and the male reproductive system. Search terms were: heavy metals AND hypospadias OR cryptorchidism NOT female NOT animal NOT review , heavy metals AND male infertility NOT female NOT animal NOT review . The same strategy was used for phthalates. RESULTS/ANTICIPATED RESULTS: We found that 12 out of 15 studies that were conducted in the Archipelago of Puerto Rico between 2000-2022 reported heavy metals- and/or phthalates- contamination in soil and water. We also found that there is a paucity of clinical studies that consider plausible relationships between a given contaminant and congenital conditions or male reproductive function. Specifically, we found that heavy metal exposure has been linked to hypospadias (n=1 study), comorbidity of hypospadias plus cryptorchidism (n= 1 study) or male infertility (n=14 studies). Phthalates exposure has been linked to comorbidity of hypospadias and cryptorchidism (n=1 study) or male infertility (n=1 study). Male subfertility has been overlooked so far. We noted that Sertoli cell dysfunction has been linked to all of these conditions. DISCUSSION/SIGNIFICANCE: The geography of Puerto Rico provides an opportunity to close the gap in knowledge between environmental contamination and male reproductive health. Based on our findings, we propose that the use of a bioassay with an immortalized Sertoli cell line can uncover the cellular processes that may be affected in male reproduction upon contaminant exposure.

Field and laboratory evaluation of PurpleAir low-cost aerosol sensors in monitoring indoor airborne particles

Due to the adverse health effects of residential air contaminants, there have been increased efforts to monitor indoor particulate matter (PM) concentration using low-cost sensors. However, little information is available about the performance of low-cost sensors in monitoring indoor aerosols. We established a research framework to examine the performance of a widely used low-cost sensor in the U.S. (PurpleAir) along with two research-grade light scattering sensors (Grimm 11-A, Sidepak AM520) in a laboratory chamber and a full-scale residential testbed. The results show that low-cost sensors can yield relatively high intra-model consistency for mass concentrations; however, the consistency is lower when measuring particles >1 μm than research-grade sensors. Regression analysis with research-grade sensors shows higher linearity for mass concentration than number concentration. These trends of mass and number concentrations are likely attributed to the size selectivity of Plantower PMS5003 sensor in PurpleAir that constrains the number fractions of specific particle size bins. The results also show that concentration discrepancy between the low-cost sensor and research-grade sensor increases as indoor mass concentration increases, suggesting that sensor quality assurance is needed for episodic indoor emission events that lead to elevated PM2.5 concentrations (>100 μg m−3).

The By-Product of Ozone from Electrostatic Air Cleaners

Indoor Air Quality (IAQ) contributes to the health and comfort of people living and working indoors. Poor IAQ can be linked to indoor and outdoor sources of contaminants. One recent solution for improving IAQ is the use of Electrostatic (ES) Air Cleaning technology. An ES air cleaner can be installed in an heating, ventilation, and air conditioning system where it pre-filters large dust particles and shocks smaller particles into a collection tray. However, ES air cleaners have been known to give off ozone as a by-product, which is, itself, an air contaminant. Ozone is found outdoors as product of sunlight combining nitrogen oxides and volatile organic compounds generated from man-made pollution. Indoor ozone concentration will depend on the introduction of outdoor ozone indoors through natural ventilation, mechanical ventilation, and infiltration through the building’s envelope (in order of importance). Two different ES air cleaners, A and B, were installed in the air conditioning system of research House #2 of the TRANE Residential Heating and Cooling Research Lab at the University of Texas at Tyler. A series of ozone experiments were conducted, which included measuring the baseline ozone levels at the research houses with different levels of insulation, observing the increase in ozone due to the powering on of mechanical ventilation, and observing the increase in ozone due to the powering on of the installed ES air cleaners. The baseline ozone levels observed in research house #2, whose envelope is more tightly insulated, was found to be lower than in research house #1 whose envelope is less tightly insulated. With regards to mechanical ventilation, an increase in ozone levels were seen in addition to an even higher increase in ozone levels when the ES air cleaners were powered on in tandem. In terms of the single contribution of the ES air cleaners in raising indoor ozone levels, the data shows that although the ES air cleaners increased the ozone concentration in the house, the levels are not of concern as they were less than the FDA limit on indoor ozone generation. KEYWORDS: Indoor Air Quality; Ozone; Electrostatic Air Cleaner; Infiltration; Mechanical Ventilation; HVAC; Pollutant; Indoor Contaminant

Air quality trends and implications pre and post Covid-19 restrictions

Air pollution causes millions of premature deaths every year. Thus, air quality assessment is essential to preserve human health and support authorities to identify proper policies. In this study, concentration levels of 6 air contaminants (benzene, carbon monoxide, nitrogen dioxide, ground level ozone, particulate matters) as monitored in 2019, 2020 and 2021 by 37 stations, located in Campania (Italy) were analysed. Particular attention has been paid to March–April 2020 period to get clues on the possible effects of the lockdown regulations, imposed in Italy from March 9th to May 4th to limit COVID-19 spread, on atmospheric pollution. Air Quality Index (AQI), an algorithm developed by the United States Environmental Protection Agency (US-EPA), allowed us to classify the air quality from moderately unhealthy to good for sensitive groups. The evaluation of air pollution impact on human health by using the AirQ+ software evidenced a significant decrement of adult mortality in 2020 respect to 2019 and 2021. Among the six pollutants considered, PM10 and PM2.5 resulted the less affected by the lockdown restrictions. Finally, a comparison between NO2 ground level concentration and the reprocessed Level 2 NO2 tropospheric column concentration obtained from satellite surveys highlighted as concentration measured at the ground level stations can be strongly influenced by the station position and its surroundings.