Environmental Protection Agency Research Articles

A Broad-Scale Look at Nutrient Limitation and a Shift toward Co-limitation in United States Lakes.

There is a longstanding debate about the role of nitrogen (N) vs phosphorus (P) in limiting primary production in lakes and whether co-nutrient limitation should be considered for managing eutrophication. We evaluated nutrient limitation and eutrophication at a subcontinental scale. Using U.S. Environmental Protection Agency National Lakes Assessment data, we assessed broad-scale patterns in nutrient limitation and compared samples of all surveyed lakes and lakes resurveyed in multiple surveys. We found that N correlated more strongly with productivity in the western U.S., while P correlated more strongly in the eastern U.S. The aggregated subcontinental effect suggests the importance of factors like N-deposition, terrestrial vegetation, underlying geology, and land use for understanding drivers of nutrient dynamics in lakes. Our study showed how patterns can aggregate across subcontinental scales yet still demonstrate considerable variation when more deeply examined on an individual lake level. Overall, we found that nutrient limitation is dynamic over space and time, with most lakes being co-limited. The prevalence of co-limitation also increased from 2007 to 2017. Trophic states within each limitation category varied substantially. Our findings underscore the need for combined N and P reductions to mitigate accelerated eutrophication.

Enantiomeric purity determination of lactofen formulations through Chemometric Deconvolution of partially overlapped chromatographic profiles

Lactofen is a chiral restricted-use herbicide, classified as toxicity class I by the Environmental Protection Agency (EPA), commonly used to control broadleaved weeds. While the observed herbicidal activity mostly derives from the (S)-(+)-enantiomer, formulations have been manufactured as a mixture of both enantiomers. In this work, we present a quantitative method for the enantiomeric determination of lactofen in commercial formulations based on the development of a second-order calibration to assist the selectivity of chiral separation under reversed-phase liquid chromatographic mode coupled to diode array detection. Chromatographic conditions were aimed to minimize analysis time and solvent consumption. This approach is feasible because second-order calibration allows for the quantification of overlapping bands and analytes in the presence of interferences. Chromatographic-spectral matrices were processed by unfolded partial least-squares coupled to residual bilinearization. The proposed methodology was evaluated through validation samples, achieving relative errors of predictions of 2–4 %. Finally, commercial formulations were subjected to minimal sample treatment and analyzed, and figures of merit for real samples were determined. The described methodology results suitable for the determination of enantiomeric purity and quality control in commercial lactofen formulations.

Assessment of Microplastic Pollution in Surface Water and Sediments of Otammiri River, Imo State, Nigeria

This study analyzed the physicochemical and heavy metal status and also quantified microplastics from Otammiri River, Imo state, Nigeria. The physicochemical and heavy metal analysis were carried out using procedures of Federal Environmental Protection Agency. The quantification of the microplastics from Otammiri River was carried out according to the National Oceanic and Atmospheric Administration (NOAA) protocol for surface water trawling for microplastics. The microplastics quantified in this study were at the range of 0.3 mm to 5mm that were resistance to wet oxidation and exhibited flotation in a 5M NaCl. The result of the physicochemical parameters showed that the parameters were within the Federal Ministry of Environment (FMEV) permissible limits with exception to lead and mercury. The microplastics concentrations at the surface water of Otammiri River was between 0.12 g to 2.50 g and in sediments samples, between 0.01 g to 1.37 g.

Screening 800 putative endocrine disrupting chemicals in a representative mammal, bird, and fish using a neurochemical cell-free testing platform

There is global demand for novel ecotoxicity testing tools that are based on alternative to animal models, have high throughput potential, and may be applicable to a wide diversity of taxa. Here we scaled up a microplate-based cell-free neurochemical testing platform to screen 800 putative endocrine disrupting chemicals from the U.S. Environmental Protection Agency's ToxCast e1k library against the glutamate (NMDA), muscarinic acetylcholine (mACh), and dopamine (D2) receptors. Each assay was tested in cellular membranes isolated from brain tissues from a representative bird (zebra finch = Taeniopygia castanotis), mammal (mink = Neogale vison), and fish (rainbow trout = Oncorhynchus mykiss). The primary objective of this short communication was to make the results database accessible, while also summarising key attributes of assay performance and presenting some initial observations. In total, 7200 species-chemical-assay combinations were tested, of which 453 combinations were classified as a hit (radioligand binding changed by at least 3 standard deviations). There were some differences across species, and most hits were found for the D2 and NMDA receptors. The most active chemical was C.I. Solvent Yellow 14 followed by Diphenhydramine hydrochloride, Gentian Violet, SR271425, and Zamifenacin. Nine chemicals were tested across multiple plates with a mean relative standard deviation of the specific radioligand binding data being 24.6%. The results demonstrate that cell-free assays may serve as screening tools for large chemical libraries especially for ecological species not easily studied using traditional methods.

Environmental pollution by mercury and trace metals in highly vulnerable afro-descendant territories in the Department of Cauca, Colombia

ABSTRACT Illegal gold mining causes mercury and trace metal contamination in many Colombian territories. The government has been requested by several ethnic communities to monitor and evaluate the state of mercury contamination in strategic ecosystems. The work aimed to evaluate mercury and trace metal contamination in a mining area located in Afro-descendant communities in the department of Cauca, Colombia. The study estimated the Hg content in different environmental compartments, such as soil, water, sediments, and trees. The level of trace metals in soil samples was assessed. It also estimated the human health risk associated with Hg from fish consumption. The concentration of T-Hg was measured using atomic absorption, and the trace element content was measured using inductively coupled plasma mass spectrometry (ICP-MS). Two out of three watersheds examined had a mean T-Hg concentration in water that exceeded the international standard limit of 2.0 µg/L set by the United States Environmental Protection Agency (USEPA). The Rattlesnake River had the highest mean concentration of T-Hg in sediments at 1.05 µg/g. The community of La Toma exceeded the maximum permissible value for T-Hg in soil. While T-Hg concentrations in C. macropomum were low at 0.02 µg/g, they were surprisingly high in Prochilodus sp. at 0.53 µg/g. F. luschnathiana trees had the highest T-Hg levels at 18.3 ± 2.3 ng/g. The soil samples analyzed showed levels of As (21.4 µg/g), Cr (148.5 µg/g), V (205.0 µg/g), and Zn (146.5 µg/g) that exceeded the maximum levels established internationally. The presence of mercury and trace elements in the communities indicates a potential risk to human and environmental health.

Enhanced perfluorooctanoic acid (PFOA) degradation by electrochemical activation of peroxydisulfate (PDS) during electrooxidation for water treatment

Improved treatment of per- and polyfluoroalkyl substances (PFAS) in water is critically important in light of the proposed United States Environmental Protection Agency (USEPA) drinking water regulations at ng L−1 levels. The addition of peroxymonosulfate (PMS) during electrooxidation (EO) can remove and destroy PFAS, but ng L−1 levels have not been tested, and PMS itself can be toxic. The objective of this research was to test peroxydisulfate (PDS, an alternative to PMS) activation by boron-doped diamond (BDD) electrodes for perfluorooctanoic acid (PFOA) degradation. The influence of PDS concentration, temperature, and environmental water matrix effects, and PFOA concentration on PDS-EO performance were systematically examined. Batch reactor experiments revealed that 99 % of PFOA was degraded and 69 % defluorination was achieved, confirming PFOA mineralization. Scavenging experiments implied that sulfate radicals (SO4–) and hydroxyl radicals (HO) played a more important role for PFOA degradation than 1O2 or electrons (e−). Further identification of PFOA degradation and transformation products by liquid chromatography-mass spectrometry (LC-MS) analysis established plausible PFOA degradation pathways. The analysis corroborates that direct electron transfers at the electrode initiate PFOA oxidation and SO4– improves overall treatment by cleaving the CC bond between the C7F15 and COOH moieties in PFOA, leading to possible products such as C7F15 and F−. The perfluoroalkyl radicals can be oxidized by SO4– and HO, resulting in the formation of shorter chain perfluorocarboxylic acids (e.g., perfluorobutanoic acid [PFBA]), with eventual mineralization to CO2 and F−. At an environmentally relevant low initial concentration of 100 ng L−1 PFOA, 99 % degradation was achieved. The degradation of PFOA was slightly affected by the water matrix as less removal was observed in an environmental river water sample (91 %) compared to tests conducted in Milli-Q water (99 %). Overall, EO with PDS provided a destructive approach for the elimination of PFOA.

Effect of electrophoretic deposition for selective detection of Pb2+ ions using nitrogen and sulphur-doped reduced graphene oxide

Lead is very hazardous, as it is present in environmental samples, and it causes severe health problems affecting neurological, cardiac, genital, and mental illnesses owing to exposure to even a trace amount. The achievement of selective detection of Pb2+ ions is challenging due to interfering relevant metal ions. Hence, in this work, we have synthesized the Nitrogen and Sulphur N and S-doped reduced graphene oxide (NS-rGO) and fabricated it using electrophoretic deposition (EPD) in glassy carbon electrode (GCE) and Bi film deposition (Bi/EPD-NS-rGO/GCE) for selective detection of Pb2+ ions. The synthesized materials were characterized to confirm their functionalities, elemental analysis, and morphology. Further, the electrochemical behaviours were also carried out through Cyclic Voltammetry (CV) and Electrochemical Impedimetric spectroscopy (EIS) studies. The above-modified electrodes were utilized for selective detection of Pb2+ in the presence of Cd2+ ionsusing the differential pulse anodic stripping voltammetry (DPASV) method. The electrode modified with NS-rGO using the EPD method, along with a thin film of Bi that was electrodeposited, has better and more selective catalytic activity for sensing Pb2+ ions. The linear working response was found to be in the range of 100–2200 nM with a limit of detection (LOD) of 0.180 nM and verified as 144 times lower than the recommended level (26 nM) by World Health Organization (WHO) and United States Environmental Protection Agency (USEPA). The developed sensor was further applied to the selective detection of Pb2+ ions in tap water and river water, and it shows good recovery. The Bi/EPD-NS-rGO/GCE will explore a new pathway for the simple and selective detection of Pb2+ ions.

The Volkswagen emissions scandal: Exploring the role of environmental concern and social norms

Nearly a decade after the 2015 emissions scandal, Volkswagen has transitioned from marketing deceptive ‘clean engine cars’ to becoming a major player in the electrification of the automotive industry. Yet, the violation of environmental standards during the scandal resulted in excessive pollutant emissions, posing persistent threats to health and the environment. This paper explores how consumers held Volkswagen accountable for these hazards. Our analysis reveals that the decline in Volkswagen’s sales volumes following the scandal was driven by environmentally concerned consumers globally. However, their reaction was short-lived and mainly limited to the models implicated by the U.S. Environmental Protection Agency. Interestingly, we find no evidence of lost sales to competitors. Instead, we document a within-brand or within-group shift in favor of Volkswagen models compliant with environmental regulations. This phenomenon could be one of the contributing factors explaining Volkswagen’s resilience in navigating the fallout from the scandal.

Exploring Climate-Disease Connections in Geopolitical Versus Ecological Regions: The Case of West Nile Virus in the United States.

Many infectious disease forecasting models in the United States (US) are built with data partitioned into geopolitical regions centered on human activity as opposed to regions defined by natural ecosystems; although useful for data collection and intervention, this has the potential to mask biological relationships between the environment and disease. We explored this concept by analyzing the correlations between climate and West Nile virus (WNV) case data aggregated to geopolitical and ecological regions. We compared correlations between minimum, maximum, and mean annual temperature; precipitation; and annual WNV neuroinvasive disease (WNND) case data from 2005 to 2019 when partitioned into (a) climate regions defined by the National Oceanic and Atmospheric Administration (NOAA) and (b) Level I ecoregions defined by the Environmental Protection Agency (EPA). We found that correlations between climate and WNND in NOAA climate regions and EPA ecoregions were often contradictory in both direction and magnitude, with EPA ecoregions more often supporting previously established biological hypotheses and environmental dynamics underlying vector-borne disease transmission. Using ecological regions to examine the relationships between climate and disease cases can enhance the predictive power of forecasts at various scales, motivating a conceptual shift in large-scale analyses from geopolitical frameworks to more ecologically meaningful regions.

Daily Fine Resolution Estimates of the Influence of Wildfires on Fine Particulate Matter in California, 2011–2020

Worsening wildfire seasons in recent years are reversing decadal progress on the reduction of harmful air pollutants in the US, particularly in Western states. Measurements of the contributions of wildfire smoke to ambient air pollutants, such as fine particulate matter (PM2.5), at fine resolution scales would be valuable to public health research on climate vulnerable populations and compound climate risks. We estimate the influence of wildfire smoke emissions on daily PM2.5 at fine-resolution, 3 km, for California 2011–2020, using a geostatistical modeled ambient PM2.5 estimate and wildfire smoke plume data from NOAA Hazard Mapping System. Additionally, we compare this product with the US Environmental Protection Agency (EPA) daily and annual standards for PM2.5 exposure. Our results show wildfires significantly influence PM2.5 in California and nearly all exceedances of the daily US EPA PM2.5 standard were influenced by wildfire smoke, while annual exceedances were increasingly attributed to wildfire smoke influence in recent years. This wildfire-influenced PM2.5 product can be applied to public health research to better understand source-specific air pollution impacts and assess the combination of multiple climate hazard risks.

Association of neighborhood-level superfund sites with atmospheric toxic exposures and increasing cancer risk in the United States: A proof-of-concept geospatial study.

10577 Background: Decades of underinvestment have disproportionately exposed several neighborhoods in the US to hazardous conditions. Superfund is the name given to the environmental program established by the US Congress in 1980, to address abandoned hazardous waste sites. The extent to which Superfund sites have contributed to differences in cancer risk remains unknown. We investigated atmospheric toxic exposures increasing cancer risk by proximity to Superfund sites at the neighborhood level. Methods: In this cross-sectional study of US neighborhoods, census-tract level air toxic cancer risk data from the Environmental Protection Agency for 2019 were linked with census-tract level geolocation data of ~1300 Superfund sites from the Superfund Enterprise Management System database. Linear regression models were utilized to explore association between cancer risk and proximity to Superfunds. Geographically Weighted Regression models explored spatial non-stationarity by modeling spatial relationships that vary across the study area. Bivariate Local Indicators of Spatial Association (LISA) cluster maps were created for superfund site proximity and cancer risk (high-high, low-low, low-high, high-low). Kruskal-Wallis testing compared the distributions of different variables across the four LISA cluster types. Results: Study explored 82,770 census tracts nationwide. For every 10 percentile increase in Superfund proximity, there was an increase of 4% in cancer risk (p < 0.001). This association was strongest in the Intermountain West, South-Southeast, and Northeast regions. High-high clusters (high proximity to Superfund, high cancer risk) had higher percentage of non-White, low-income, unemployed and lower education attainment populations compared to low-low clusters (all p < 0.001). Within high-high clusters, non-White population had the strongest correlation with proximity to Superfunds. Cancer risk was much higher for the top 10% than the bottom 10% of proximity to Superfunds (Table). Conclusions: Our study highlights higher clustering of cancer risk around neighborhoods with existing Superfund sites. Further, we demonstrate the closer a neighborhood is to a Superfund site, the greater the cancer risk is with associated sociodemographic changes. Using a novel approach to geospatial analytics, the results demonstrate the first clear evidence of a dangerous association between Superfunds and healthcare, and encourage the urgent prioritization of Congressional policies that optimize investment in Superfund site clean up for public health. [Table: see text]

Concordance among lacustrine communities are low and inconsistent in the conterminous United States.

Concordance occurs when two or more biological groups are correlated to each other. Examining the degree of concordance between communities has been a central goal in ecology. However, few studies have assessed the levels of community concordance at large spatial scales. We used a dataset obtained by the National Lakes Assessment (United States Environmental Protection Agency) to evaluate whether (i) the levels of concordance between aquatic communities were higher at the continental scale than within individual ecoregions of the United States and (ii) whether the levels of concordance between phytoplankton and zooplankton were higher than those between the plankton and macroinvertebrates communities. At the continental scale, the levels of concordance between different pairs of aquatic communities were low and did not exceed those within the ecoregions. Furthermore, levels of concordance varied considerably among ecoregions. Our results suggest that interactions between aquatic communities likely determined concordance patterns; however, the expectation of higher levels of concordance between the phytoplankton and zooplankton communities than between them and the macroinvertebrates community was not supported. The consistently low and variable levels of concordance suggest that using surrogate groups is not recommendable for monitoring lakes in the United States, both at the continental and regional scales. According to our results, the prospect of using the surrogacy approach was low even for aquatic communities that are highly interactive or driven by similar environmental factors.

Navigating the regulatory landscape: US environmental regulations pertaining to CO2 emissions

Amid growing apprehensions regarding climate change, regulatory frameworks governing carbon dioxide emissions play a crucial role in shaping industrial practices, energy policies, and environmental sustainability efforts. Through an examination of key regulatory bodies, such as the Environmental Protection Agency (EPA) and relevant legislation such as the Clean Air Act, this paper analyzes the intricate web of regulations governing CO2 emissions across various sectors. Additionally, the paper explores recent developments, including regulatory updates, policy shifts, and emerging trends, highlighting their implications for businesses, policymakers, and environmental advocates. By synthesizing complex regulatory information into a concise and accessible format, this paper aims to provide valuable insights for stakeholders navigating the dynamic landscape of US environmental regulations pertaining to CO2 emissions.

Spatial variations in metals of groundwater in Naini industrial area: assessing probable sources and human health risk

ABSTRACT Groundwater forms the major source of drinking water worldwide; however, its quality has been compromised due to various human activities. The contamination of groundwater with metals have increased the health risk of the consumers. In pursuit of risk assessment and source apportionment studies of groundwater of Naini Industrial Area, Prayagraj, Uttar Pradesh, India; groundwater samples (n = 60) were collected from distinct sampling locations spanning the study area. Inductively coupled plasma-mass spectrometry (ICP-MS) was employed to analyse the concentrations of Aluminium (Al), Arsenic (As), Barium (Ba), Cadmium (Cd), Chromium (Cr), Cobalt (Co), Copper (Cu), Iron (Fe), Manganese (Mn), Nickel (Ni), Lead (Pb), Selenium (Se), Strontium (Sr), Vanadium (V) and Zinc (Zn). Amongst all the metals analysed, Al and Fe surpassed drinking water standards in more than 50% of the samples. Principal component analysis (PCA) extracted four factors that collectively accounted for 76.3% of the variability in the data. As illustrated by PCA, metals in the groundwater can be attributed to geological origins combined with anthropogenic contributions. Considering the central tendency of the metals, the non-cancer risk as per United States Environmental Protection Agency (USEPA) methodology depicted by Hazard Quotient (HQ) of the metals did not exceed unity and can be inferred that they did not pose risk to the human health individually. However, the combined risk of the metals as depicted by Hazard Index (HI) suggested considerable hazard to the child residents with HI value of 1.27. Across all the sampled sites, the HI values varied from 0.48 to 4.07 for males, 0.41 to 3.51 for females, and 0.76 to 6.51 for children. Considering central tendency, carcinogenic risk associated with As and Cr was determined to be within the tolerable cancer risk value of 1 × 10−4. Nevertheless, the cancer risk for the groundwater surpassed the acceptable limit in few of the locations rendering them unsuitable for drinking without treatment.

Microbial pesticides – challenges and future perspectives for testing and safety assessment with respect to human health

Plant protection measures are necessary to prevent pests and diseases from attacking and destroying crop plants and to meet consumer demands for agricultural produce. In the last decades the use of chemical pesticides has largely increased. Farmers are looking for alternatives. Biopesticides should be considered a sustainable solution. They may be less toxic than chemical pesticides, be very specific to the target pest, decompose quickly, and be less likely to cause resistance. On the other hand, lower efficacy and higher costs are two disadvantages of many biopesticides. Biopesticides include macroorganisms, natural compounds and microorganisms. Microbial pesticides are the most widely used and studied class of biopesticides. The greatest difference between microbial and chemical pesticides is the ability of the former to potentially multiply in the environment and on the crop plant after application. The data requirements for the European Union and the United States Environmental Protection Agency are highlighted, as these regulatory processes are the most followed in regions where local regulations for biopesticide products are not available or vague. New Approach Methods already proposed or harmonized for chemical pesticides are presented and discussed with respect to their use in evaluating microbial pesticide formulations. Evaluating the microbials themselves is not as simple as using the same validated New Approach Methods as for synthetic pesticides. Therefore, the authors suggest considering New Approach Method strategies specifically for microbials and global harmonization with acceptability with the advancements of such approaches. Further discussion is needed and greatly appreciated by the experts.

Evaluation and health risk assessment of arsenic and potentially toxic elements pollution in groundwater of Majha Belt, Punjab, India.

Concentrations of potentially toxic elements (PTEs) like arsenic, uranium, iron, and nitrate in the groundwater of the Majha Belt (including Tarn Taran, Amritsar, Gurdaspur, and Pathankot districts) in Punjab, India were measured to evaluate the health risks associated with its consumption and daily use. The average concentrations of these elements in some locations exceeded the WHO-recommended values. Arsenic and iron toxicity levels were found to be higher in the Amritsar district, while uranium toxicity was more prevalent in Tarn Taran. The Trace Element Evaluation Index suggests that Amritsar is one of the districts most affected by toxic elements. According to the US Environmental Protection Agency's (USEPA) guidelines, the HQ values of U, Fe, and nitrate were less than one, indicating that there is no non-carcinogenic health risk for adults and children. However, the hazard quotient (HQ) value for arsenic was greater than one, indicating a higher possibility of health risk due to arsenic in the study area. The total hazard index values of 44.10% of samples were greater than four for arsenic, indicating that people in the Majha Belt are at a very high health risk due to the usage of water for drinking and domestic purposes. The cancer risk assessment values for arsenic in children (5.69E + 0) and adults (4.07E + 0) were higher than the accepted limit of USEPA (10-4 to 10-6) in the Majha Belt. The average radiological cancer risk values of U for children and adults were 8.68E-07 and 9.45E-06, respectively, which are well below the permissible limit of 1.67 × 10-4 suggested by the Atomic Energy Regulatory Board of DAE, India. The results of this study confirm that the residents of the Majha Belt who use contaminated groundwater are at a serious risk of exposure to arsenic in the Amritsar district and uranium in Tarn Taran district.

Intraspecific variation in mercury contamination of alligator snapping turtles (Macrochelys temminckii).

Macrochelys temminckii (alligator snapping turtle) is an aquatic turtle endemic to the southeastern United States that was proposed for listing under the Endangered Species Act in 2021. In the present study we analyzed total mercury (THg) concentrations in skeletal muscle, tail clips, and nail tissue of 93 M. temminckii sampled from 14 waterbodies in eastern Texas (USA). Our objectives were to assess (1) the degree of correlation between internal tissue (skeletal muscle and tail clip samples) and keratin (nail samples), (2) the influence of ecological factors (turtle size and waterbody/sampling site) on THg concentrations, and (3) whether THg concentrations were high enough to pose a risk to human consumers. The mean (±SE) THg concentrations of muscle and nail were 1.16 ± 0.08 μg/g dry weight and 4.21 ± 0.24 μg/g dry weight, respectively, and THg concentrations were highly dependent on the sampling site. The THg concentrations of nails were correlated with muscle concentrations (R2 = 0.56, p < 0.001). The effect of body size on THg concentrations varied by sampling site, indicating that size is not a good predictor of Hg concentration across sites. Finally, THg concentrations in M. temminckii of eastern Texas were high enough to pose a potential risk to human health based on US Environmental Protection Agency dietary guidelines. Environ Toxicol Chem 2024;00:1-11. © 2024 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Investigation of the pollutant load of artisanal-refined gasoline in the Niger Delta region of Nigeria and its implications on air quality

In order to examine the gaseous pollutants generated by artisanal refined gasoline and the contribution to air pollution associated with such combustion in the Niger-Delta region of Nigeria, this study collected a sample of indigenously refined gasoline product each from thirty (30) different randomly selected artisanal camps in the Niger-Delta region and subjected all the collected samples to combustion. Fifty (50) ml of each gasoline sample was combusted at controlled conditions, and the concentrations of gaseous emissions from the process were measured using a combustion emission analyser. Pollutants characterised by the Department of Petroleum Resources which include sulphur dioxide (SO2), carbon monoxide (CO), oxides of nitrogen (NOx), hydrocarbons (HC) and carbon dioxide (CO2) were characterised. The average concentrations of the emissions were 211.50 mg/m3, 7.18 mg/m3, 17.51 mg/m3, 3011.33 mg/m3, and 500.39 mg/m3 for CO, NOx, SO2, CO2, and HC respectively. The concentrations of SO2 and NOx measured were within the Federal Environmental Protection Agency (FEPA) set limits for combustion emissions from stationary sources but breached World Health Organization (WHO), World Bank and Environmental Guidelines and Standard for Petroleum Industry in Nigeria (EGASPIN) set limits. The concentrations of CO and HC exceeded FEPA, WHO, World Bank and EGASPIN set limits and hazardous on Air Quality Index (AQI) classification. Elevated concentrations of CO and HC in the atmosphere pose a major threat to ambient air quality and human health, especially in locations where artisanal-refined fuel is predominantly utilised. Associated risks include poor visibility, occurrence of acid rain, blood poisoning and cancer-related diseases. In addition to these effects are the worsening global warming crises associated with CO2 emission, a major product of fossil fuel combustion.

Multi-omic integration reveals alterations in nasal mucosal biology that mediate air pollutant effects on allergic rhinitis.

Allergic rhinitis is a common inflammatory condition of the nasal mucosa that imposes a considerable health burden. Air pollution has been observed to increase the risk of developing allergic rhinitis. We addressed the hypotheses that early life exposure to air toxics is associated with developing allergic rhinitis, and that these effects are mediated by DNA methylation and gene expression in the nasal mucosa. In a case-control cohort of 505 participants, we geocoded participants' early life exposure to air toxics using data from the US Environmental Protection Agency, assessed physician diagnosis of allergic rhinitis by questionnaire, and collected nasal brushings for whole-genome DNA methylation and transcriptome profiling. We then performed a series of analyses including differential expression, Mendelian randomization, and causal mediation analyses to characterize relationships between early life air toxics, nasal DNA methylation, nasal gene expression, and allergic rhinitis. Among the 505 participants, 275 had allergic rhinitis. The mean age of the participants was 16.4 years (standard deviation = 9.5 years). Early life exposure to air toxics such as acrylic acid, phosphine, antimony compounds, and benzyl chloride was associated with developing allergic rhinitis. These air toxics exerted their effects by altering the nasal DNA methylation and nasal gene expression levels of genes involved in respiratory ciliary function, mast cell activation, pro-inflammatory TGF-β1 signaling, and the regulation of myeloid immune cell function. Our results expand the range of air pollutants implicated in allergic rhinitis and shed light on their underlying biological mechanisms in nasal mucosa.

Occupational exposure, carcinogenic and non-carcinogenic risk assessment of formaldehyde in the pathology labs of hospitals in Iran

Formaldehyde, a known carcinogenic compound, is commonly used in various medical settings. The objective of this study was to assess the carcinogenic and non-carcinogenic risks associated with occupational exposure to formaldehyde. This study was conducted in the pathology labs of four hospitals in Tehran. Cancer and non-cancer risks were evaluated using the quantitative risk assessment method proposed by the United States environmental protection agency (USEPA), along with its provided database known as the integrated risk information system (IRIS). Respiratory symptoms were assessed using the American thoracic society (ATS) questionnaire. The results indicated that 91.23% of exposure levels in occupational groups exceed the NIOSH standard of 0.016 ppm. Regarding carcinogenic risk, 41.03% of all the studied subjects were in the definite carcinogenic risk range (LCR > 10−4), 23.08% were in the possible carcinogenic risk range (10−5 < LCR < 10−4), and 35.90% were in the negligible risk range (LCR < 10−6). The highest index of occupational carcinogenesis was observed in the group of lab technicians with a risk number of 3.7 × 10−4, followed by pathologists with a risk number of 1.7 × 10−4. Furthermore, 23.08% of the studied subjects were within the permitted health risk range (HQ < 1.0), while 76.92% were within the unhealthy risk range (HQ > 1.0). Overall, the findings revealed significantly higher carcinogenic and non-carcinogenic risks among lab technicians and pathologists. Therefore, it is imperative to implement control measures across various hospital departments to mitigate occupational formaldehyde exposure levels proactively. These findings can be valuable for policymakers in the health sector, aiding in the elimination or reduction of airborne formaldehyde exposure in work environments.