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Sensors (Basel, Switzerland) Jun 2023This communication investigated the dust effect on microelectromechanical system (MEMS) thermal wind sensors, with an aim to evaluate performance in practical...
This communication investigated the dust effect on microelectromechanical system (MEMS) thermal wind sensors, with an aim to evaluate performance in practical applications. An equivalent circuit was established to analyze the temperature gradient influenced by dust accumulation on the sensor's surface. The finite element method (FEM) simulation was carried out to verify the proposed model using COMSOL Multiphysics software. In experiments, dust was accumulated on the sensor's surface by two different methods. The measured results indicated that the output voltage for the sensor with dust on its surface was a little smaller than that of the sensor without dust at the same wind speed, which can degrade the measurement sensitivity and accuracy. Compared to the sensor without dust, the average voltage was reduced by about 1.91% and 3.75% when the dustiness was 0.04 g/mL and 0.12 g/mL, respectively. The results can provide a reference for the actual application of thermal wind sensors in harsh environments.
Topics: Dust; Wind; Micro-Electrical-Mechanical Systems; Temperature; Software
PubMed: 37420700
DOI: 10.3390/s23125533 -
International Journal of Environmental... Nov 2021Indoor dust can be a major source of heavy metals, nutrients, and bacterial contamination in residential environments and may cause serious health problems. The goal of...
Indoor dust can be a major source of heavy metals, nutrients, and bacterial contamination in residential environments and may cause serious health problems. The goal of this research is to characterize chemical and bacterial contaminants of indoor, settled house dust in the Houston Metropolitan region. To achieve this, a total of 31 indoor dust samples were collected, along with household survey data, which were subsequently analyzed for elemental and bacterial concentrations. Microscopic and geospatial analysis was conducted to characterize and map potential hotspots of contamination. Interestingly Cd, Cr, Cu, Pb, and Zn concentrations of all 31 indoor dust samples were significantly enriched and exceeded soil background concentrations. Furthermore, As, Cd, Pb, and Zn concentrations in the dust samples were significantly correlated to the enteric bacterial load concentrations. Human health assessment revealed that cancer risk values via ingestion for Cd, Cr, and Ni were greater than the acceptable range. Of our 31 dust sample isolates, three Gram-negative and 16 Gram-positive pathogenic bacteria were identified, capable of causing a wide range of diseases. Our results demonstrate that both chemical and bacterial characterization of indoor dust coupled with spatial mapping is essential to assess and monitor human and ecological health risks.
Topics: Bacteria; China; Cities; Dust; Environmental Monitoring; Humans; Metals, Heavy; Risk Assessment; Texas
PubMed: 34886125
DOI: 10.3390/ijerph182312399 -
Biological & Pharmaceutical Bulletin 2022In many epidemiological studies, the dust extinction coefficient measured by light detection and ranging (LIDAR) is used as an indicator of exposure to Asian dust....
In many epidemiological studies, the dust extinction coefficient measured by light detection and ranging (LIDAR) is used as an indicator of exposure to Asian dust. However, few reports on the relationship between the distribution of total suspended particles (TSPs) near the ground surface and the dust extinction coefficient exist. In this study, we examined the relationship between the concentrations of TSPs near the ground surface, substances indicative of mineral content, and air pollutants that may be transported with Asian dust and dust extinction coefficients in two regions: Imizu and Yurihama-Matsue, from March to May in 2011 and 2013. In both years, large dust extinction coefficients were observed in Imizu and Matsue on days when the concentrations of TSPs and mineral content indicators were high near the ground surface in Imizu and Yurihama, and Asian dust was expected to be highly suspended. In both regions, the concentrations of TSPs and mineral content indicators were significantly positively correlated with the dust extinction coefficient. The concentrations of all air pollutants analyzed were significantly positively correlated with the dust extinction coefficient in each region in 2013, but not in 2011. These results suggest that the dust extinction coefficient is a useful indicator of Asian dust near the ground surface; however, as harmful air pollutants occasionally move with Asian dust, it is necessary to monitor these pollutants near the ground surface when conducting an epidemiological study on the health effect of airborne particles.
Topics: Air Pollutants; Dust; Minerals
PubMed: 35650099
DOI: 10.1248/bpb.b21-00941 -
Environment International Jan 2022The atmosphere is a potential pathway for global-scale and long-range dispersal of viable microorganisms, promoting biological interconnections among the total...
The atmosphere is a potential pathway for global-scale and long-range dispersal of viable microorganisms, promoting biological interconnections among the total environment. We aimed to provide relevant baseline information for long-range long-term intercontinental exchange of potentially infectious airborne microorganisms of major interest in environmental and health-related disciplines. We used an interannual survey (7-y) with wet depositions fortnightly collected above the boundary layer (free troposphere) at a remote high-elevation LTER (Long-Term-Ecological-Research) site, analyzed by 16S and 18S rRNA genes, and compared to a database of 475 well-known pathogens. We applied a conservative approach on close relatives of pathogenic species (>98% identity) standing their theoretical upper limit for atmospheric baseline relative abundances. We identified c. 2-3% of the total airborne microbiota as potential pathogens. Their most frequent environmental origins were soil, aquatic, and anthropogenic sources. Phytopathogens (mostly fungi) were the potential infectious agents most widely present. We uncovered consistent interannual dynamics with taxa foreseeable over time (i.e., predictable seasonal behavior) and under recurrent environmental scenarios (e.g., Saharan dust intrusions), respectively, being highly valuable microbial forensic environmental indicators. Up to 8 bacterial and 21 fungal genera consistently showed temporal abundances and recurrences unevenly distributed. Incidence of allergenic fungi was lower in summer, and significantly higher in spring. Close relatives to Coccidioides posadasii consistently showed higher signals (i.e., high specificity and high fidelity) in winter, whereas Cryptococcus neoformans had a significant signal in spring. Along Saharan dust intrusions, the bacterial phytopathogens Acidovorax avenae and Agrobacterium tumefaciens and the fungal phytopathogens Pseudozyma hubeiensis and Peniophora sp. consistently showed higher signals. Potential human pathogens showed low proportion, being mostly fungal allergens. Microorganisms related to obligated human, amphibian and fish pathogens were commonly found in winter. More studies in remote field sites above the boundary layer will unveil whether or not a similar trend is found globally.
Topics: Air Microbiology; Animals; Atmosphere; Dust; Environmental Monitoring; Fungi; Humans; Seasons
PubMed: 34627012
DOI: 10.1016/j.envint.2021.106916 -
International Journal of Environmental... Nov 2022The soil environment contributes considerably to human exposure to metals. This study aimed to comprehensively compare children's exposure to soil metals using different...
The soil environment contributes considerably to human exposure to metals. This study aimed to comprehensively compare children's exposure to soil metals using different sampling approaches (i.e., hand wipe, indoor dust and outdoor soil) and assessment strategies, combing the method of external exposure evaluation and the correlation with internal biomarkers. Environmental exposure samples (hand wipe, outdoor soil and indoor dust), blood samples and child-specific exposure factors were simultaneously collected for 60 children aged 3 to 12 years from an area of northwestern China. Eight typical toxic metals were analyzed. Results showed that metal levels in hand wipes were associated with children's age, years of residency and the ground types of the play areas. Hand-to-mouth contact was an important pathway for children's metal exposure, with the corresponding oral exposure cancer risk to Cr already exceeding the maximum acceptable level. In comparison, metal concentrations in hand wipes were one to seven times higher than those in outdoor soil and indoor dust. Even greater discrepancies were found for the estimated exposure dose, which could lead to differences of several to dozens of times. In addition, Pb, Mn and Cr in hand wipes were significantly correlated with those in blood, whereas no relationships were found with soil and dust. This study indicates that the selection of different sampling and assessing strategies could lead to great differences in children metal exposure outcomes. It also suggests that hand wipe, which could reflect the true and integrated exposure level and the individual difference, serves as a better matrix to assess children's metal exposure compared to soil and dust. Further studies should standardize the sampling method for hand wipes and verify its applicability for other age groups.
Topics: Humans; Dust; Soil; Air Pollution, Indoor; Environmental Exposure; Metals; Biomarkers; Environmental Monitoring
PubMed: 36361494
DOI: 10.3390/ijerph192114614 -
The Science of the Total Environment Nov 2022Adults can be exposed to chemicals through incidental ingestion of soil and dust, either through hobbies, occupations, or behaviors that increase contact with soil or...
BACKGROUND
Adults can be exposed to chemicals through incidental ingestion of soil and dust, either through hobbies, occupations, or behaviors that increase contact with soil or dust (e.g., cleaning or renovating). However, few data describing these ingestion rates are available.
OBJECTIVE
Our objective was to use the Stochastic Human Exposure and Dose Simulation Soil and Dust (SHEDS-Soil/Dust) model to estimate distributions of soil and dust ingestion rates for adults (≥21 years old) with varying degrees of soil and dust contact.
METHODS
We parameterized SHEDS-Soil/Dust to estimate soil and dust ingestion rates for several categories of adults: adults in the general population; adults with moderate (higher) soil exposure (represented by hobbyists, such as gardeners, with increased soil contact); adults with high soil exposure (represented by occupationally exposed individuals, such as landscapers); and individuals who have high dust exposure (e.g., are in contact with very dusty indoor environments).
RESULTS
Total soil plus dust ingestion for adults in the general population was 7 mg/day. Hobbyists or adults with moderate soil exposure averaged 33 mg/day and occupationally exposed individuals averaged 123 mg/day. Total soil plus dust ingestion for adults in the high dust exposure scenario was 25 mg/day. Results were driven by time spent in contact with soil and, thus, warmer seasons (e.g., summer) were associated with higher ingestion rates than colder seasons (e.g., winter).
SIGNIFICANCE
These results provide modeled estimates of soil and dust ingestion rates for adults for use in decision making using real-world exposure considerations. These modeled estimates suggest that soil and dust ingestion is a potential concern for adults who spend a higher amount of time interacting with either soil or dusty environments.
IMPACT STATEMENT
The parameterization of real-world scenarios within the application of SHEDS-Soil/Dust model to predict soil and dust ingestion rates for adults provides estimates of soil and dust ingestion rates useful for refining population-based risk assessments. These data illuminate drivers of exposure useful for both risk management decisions and designing future studies to improve existing tracer methodologies.
Topics: Adult; Computer Simulation; Dust; Eating; Environmental Exposure; Humans; Soil; Young Adult
PubMed: 35870603
DOI: 10.1016/j.scitotenv.2022.157501 -
Journal of Hazardous Materials Mar 2023The widespread application of glyphosate leads to significant contamination of outdoor environmental compartments, notably air and soil, which can contaminate indoor air...
Determination of glyphosate and AMPA in indoor settled dust by hydrophilic interaction liquid chromatography with tandem mass spectrometry and implications for human exposure.
The widespread application of glyphosate leads to significant contamination of outdoor environmental compartments, notably air and soil, which can contaminate indoor air and dust. This study assessed the contamination of indoor household dust for the first time in France and potential exposure to glyphosate through the inadvertent ingestion of dust. A specific and new analytical method was developed using HILIC MS/MS (hydrophilic interaction liquid chromatography with tandem mass spectrometry) to measure polar pesticides, such as glyphosate, aminomethylphosphonic acid, and glufosinate, in indoor dust, with a low quantification limit (25 ng/g). The dust from vacuum cleaner bags of 60 rural and urban households (Brittany, France) was analyzed. All samples contained glyphosate (median 1675 ng/g for rural dwellings (n = 29), 457 ng/g for urban dwellings (n = 31)), more than 90 % contained aminomethylphosphonic acid, and none contained glufosinate. Concentrations were influenced by the rural or urban setting, the proximity of crops, and the use of weed killers on driveways or lawns. Glyphosate exposure via indoor dust ingestion was < 1 % of both acceptable daily intake and dietary intake. However, the high quantification limit of the glyphosate concentration in the food analysis method probably leads to overestimation of the dose from food.
Topics: Humans; Tandem Mass Spectrometry; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; Dust; Chromatography, Liquid; Hydrophobic and Hydrophilic Interactions; Glyphosate
PubMed: 36608580
DOI: 10.1016/j.jhazmat.2022.130654 -
Environment International Apr 2022Human exposure to per- and polyfluoroalkyl substances (PFAS) has been primarily attributed to contaminated food and drinking water. There is information indicating other...
BACKGROUND
Human exposure to per- and polyfluoroalkyl substances (PFAS) has been primarily attributed to contaminated food and drinking water. There is information indicating other sources and pathways of exposure in residential environments, but few studies report relationships between these indoor media and human biomonitoring measurements.
METHODS
This study adapts existing systematic review tools and methodologies to synthesize evidence for PFAS exposure pathways from indoor environment media including consumer products, household articles, cleaning products, personal care products, and indoor air and dust. Studies were identified using innovative machine learning approaches and pathway-specific search strings to reduce time needed for literature search and screening. The included studies and systematic review were evaluated using tools modified specifically for exposure studies. The systematic review was conducted following a previously published protocol (DeLuca et al., 2021) that describes the systematic review methodology used in detail.
RESULTS
Only 7 studies were identified that measured the targeted subset of 8 PFAS chemicals in concordant household media (primarily house dust) and participant serum. Data extracted from the included studies were used to calculate exposure intake rates and estimate a percentage of occupant serum concentrations that could be attributed to the indoor exposure pathways. These calculations showed that exposure to PFOA, PFOS, PFNA, and PFHxS from contaminated house dust could account for 13%, 3%, 7%, and 25% of serum concentrations, respectively. Inhalation of PFAS in indoor air could account for less than 4% of serum PFOA concentrations and less than 2% of serum PFOS and PFNA concentrations. A risk of bias was identified due to participant profiles in most of the studies being skewed towards white, female, and higher socioeconomic status.
CONCLUSIONS
Along with synthesizing evidence for estimated contributions to serum PFAS levels from indoor exposure media, this systematic review also identifies a consistent risk of bias across exposure study populations that should be considered in future studies. It highlights a major research gap and need for studies that measure concordant data from both indoor exposure media and participant serum and the need for continued research on exposure modeling parameters for many PFAS chemicals.
Topics: Alkanesulfonic Acids; Biological Monitoring; Culture Media; Drinking Water; Dust; Environmental Pollutants; Female; Fluorocarbons; Humans
PubMed: 35240384
DOI: 10.1016/j.envint.2022.107149 -
International Journal of Environmental... Oct 2021Rapid urbanization and industrialization have led to the accumulation of heavy metals in urban areas. The distribution and health risk of heavy metals in soil and street...
Rapid urbanization and industrialization have led to the accumulation of heavy metals in urban areas. The distribution and health risk of heavy metals in soil and street dust were studied by collecting the samples in pairs from different land uses in Changsha, China. The results showed that the average contents of the heavy metals Pb, Cd, Cu, Zn, Cr and Ni in the soil were 45.3, 0.69, 46.3, 220.4, 128.7 and 32.9 mg·kg, and the corresponding heavy metal contents in the street dust were 130.1, 3.9, 130.8, 667.2, 223.2, 50.5 mg·kg, respectively. The soils in the parks and roadsides have higher heavy metal contents than those in the residential and agricultural areas. The street dust collected from parks, roadsides and residential areas contained higher heavy metal contents than agricultural areas. Significant correlations were found between heavy metals, suggesting similar sources. However, most of the heavy metals in the soil were uncorrelated with those in the street dust. The contents of heavy metals in soil are the results of long-term pollution. Street dust is easily affected by natural or human disturbances, reflecting pollution emissions in a short period. The health risks posed by heavy metals in the soil are acceptable, but the street dust may threaten children's health, especially in residential areas. Pb, Cr and Cd are the main risk contributors. Reducing the emissions from industrial plants and traffic may reduce the risk of exposure to heavy metals in the street dust.
Topics: Child; China; Cities; Dust; Environmental Monitoring; Humans; Metals, Heavy; Risk Assessment; Soil; Soil Pollutants
PubMed: 34682490
DOI: 10.3390/ijerph182010733 -
Environment International Jan 2021The ubiquity of organophosphate esters (OPEs) in various environmental matrices inevitably pose human exposure risks. Numerous studies have investigated human exposure... (Review)
Review
The ubiquity of organophosphate esters (OPEs) in various environmental matrices inevitably pose human exposure risks. Numerous studies have investigated human exposure pathways to OPEs, including air inhalation, dust ingestion, dermal contact, and dietary and drinking water intake, and have indicated that indoor dust and indoor air routes are frequently the two main human exposure pathways. This article reviews the literature on OPE contamination in indoor air and dust from various microenvironments and on OPE particle size distributions and bioavailability in dust conducted over the past 10 years. Ways in which sampling strategies are related to the uncertainty of exposure assessment results and comparability among different studies in terms of sampling tools, sampling sites, and sample types are addressed. Also, the associations of OPEs in indoor dust/air with human biological samples were summarized. Studies on two emerging matrices, hand wipes and silicone wristbands, are demonstrated to be more comprehensive and accurate in reflecting personal human exposure to OPEs in microenvironments and are summarized. Given the direct application of some diester OPEs (di-OPEs) in numerous products, research on their existence in indoor dust and food and on their effects on human urine are also discussed. Finally, related research trends and avenues for future research are prospected.
Topics: Air Pollution, Indoor; China; Dust; Environmental Exposure; Environmental Monitoring; Esters; Flame Retardants; Humans; Organophosphates; Silicones
PubMed: 33395927
DOI: 10.1016/j.envint.2020.106261