Sex-Specific Association of Ambient Temperature With Urine Biomarkers in Southwest Coastal Bangladesh.

Introduction: Men are vulnerable to ambient heat-related kidney disease burden; however, limited evidence exists on how vulnerable women are when exposed to high ambient heat. We evaluated the sex-specific association between ambient temperature and urine electrolytes, and 24-hour urine total protein, and volume. Methods: We pooled a longitudinal 5624 person-visits data of 1175 participants' concentration and 24-hour excretion of urine electrolytes and other biomarkers (24-hour urine total protein and volume) from southwest coastal Bangladesh (Khulna, Satkhira, and Mongla districts) during November 2016 to April 2017. We then spatiotemporally linked ambient temperature data from local weather stations to participants' health outcomes. For evaluating the relationships between average ambient temperature and urine electrolytes and other biomarkers, we plotted confounder-adjusted restricted cubic spline (RCS) plots using participant-level, household-level, and community-level random intercepts. We then used piece-wise linear mixed-effects models for different ambient temperature segments determined by inflection points in RCS plots and reported the maximum likelihood estimates and cluster robust standard errors. By applying interaction terms for sex and ambient temperature, we determined the overall significance using the Wald test. Bonferroni correction was used for multiple comparisons. Results: The RCS plots demonstrated nonlinear associations between ambient heat and urine biomarkers for males and females. Piecewise linear mixed-effects models suggested that sex did not modify the relationship of ambient temperature with any of the urine parameters after Bonferroni correction (P < 0.004). Conclusion: Our findings suggest that women are as susceptible to the effects of high ambient temperature exposure as men.

Quantitative analysis of microplastics in seawater based on SERS internal standard method.

Microplastics can enter the human body through the food chain and can cause cardiovascular or cerebrovascular diseases; thus, it is essential to detect microplastics sensitively and accurately. Traditional methods have some drawbacks, such as a low sensitivity and complicated experimental procedures, so it is difficult to detect microplastics less than 1 µm. While surface enhanced Raman scattering technology can compensate for these shortcomings, there are fewer reports on the quantitative detection of microplastics using SERS technology. In this study, SERS and an internal standard method were utilized to detect microplastics qualitatively and quantitatively. The electric field enhancement effect of common gold, silver, and copper substrates were simulated by the finite element method, and the influence rule of structural parameters on the enhancement factor was obtained to optimize structural parameters. Subsequently, a gold nanopyramid array substrate was prepared using the colloidal sphere template method. Finally, the prepared substrate was applied to detect polystyrene microplastics with a diameter of 500 nm, and the detection of limit is 1.8 × 10-4 mg mL-1 in the quantitative range of 2-2 × 10-4 mg mL-1, and the correlation coefficient of the linear regression equation is 0.9918. The experimental results showed that this proposal has a lower detection limit and a wider quantitative range and expands ideas for the qualitative and quantitative detection of microplastics in seawater.

Indoor Bacterial and Fungal Burden in "Moldy" versus "Non-Moldy" Homes: A Case Study Employing Advanced Sequencing Techniques in a US Metropolitan Area.

The presence of fungi in the indoor environment is associated with allergies and other respiratory symptoms. The aim of this study was to use sequencing and molecular methods, including next-generation sequencing (NGS) approaches, to explore the bacterial and fungal communities and their abundance in the indoor environment of houses (n = 20) with visible "moldy" (HVM) and nonvisible "non-moldy" (HNM) in Memphis, TN, USA. Dust samples were collected from air vents and ground surfaces, and the total DNA was analyzed for bacteria and fungi by amplifying 16S rRNA and ITS genes on the Illumina Miseq. Results indicated that Leptosphaerulina was the most abundant fungal genus present in the air vent and ground samples from HNM and HVM. At the same time, the most abundant bacterial genera in the air vent and ground samples were Propionibacterium and Streptococcus. The fungi community diversity was significantly different in the air vent samples. The abundance of fungal species known to be associated with respiratory diseases in indoor dust samples was similar, regardless of the visibility of fungi in the houses. The existence of fungi associated with respiratory symptoms was compared with several parameters like dust particulate matter (PM), CO2 level, temperature, and humidity. Most of these parameters are either positively or negatively correlated with the existence of fungi associated with respiratory diseases; however, none of these correlations were significant at p = 0.05. Our results indicate that implementing molecular methods for detecting indoor fungi may strengthen common exposure and risk assessment practices.

Size distribution and lung-deposition of ambient particulate matter oxidative potential: A contrast between dithiothreitol and ascorbic acid assays.

Particulate matter (PM) inhaled into human lungs causes oxidative stress and adverse health effects through antioxidant depletion (oxidative potential, OP). However, there is limited knowledge regarding the association between the lung-deposited dose (LDD) of PM and OP in extrathoracic (ET), tracheobronchial (TB), and pulmonary (P) regions of human lungs. Dithiothreitol (DTT) and ascorbic acid (AA) assays were employed to measure the OP of PM size fractions to investigate OP distribution in human lungs and identify the chemical drivers. Quasi-ultrafine particles (quasi-UFP, ≤0.49 µm) exhibited high OP deposition in the TB and P regions, while coarse particles (CP, ≥3.0 µm) dominated in the ET region. A plot of extrinsic (per air volume) and intrinsic (per PM mass) OP versus LDD revealed that the OP for fine and coarse particles was greatest in the ET region, whereas the OP of quasi-UFP was greatest in alveoli. The study also demonstrated that extrinsic OP and PM doses are not strongly related. The decline in OP with increasing PM dose reveals the need for further investigation of the antagonistic effects of the chemical compositions. Overall, the results presented herein help address the gap in knowledge regarding the association between the OP and LDD of ambient particles in specific regions of human lungs.

Dataset of atmospheric concentrations of polycyclic aromatic hydrocarbons in the Memphis Tri-state Area.

This dataset contains concentrations (in ng/m3) of 32 polycyclic aromatic hydrocarbons (PAHs) in the ambient air in the Memphis Tri-state Area (MTA). In the atmosphere, PAHs are toxic pollutants emitted from incomplete combustion sources. This monitoring campaign was conducted at 19 sites in three neighboring counties in Tennessee, Mississippi, and Arkansas, i.e., MTA, over one year. The monitoring sites represented industrial, urban, suburban, and remote land types. Total suspended particulate (TSP) samples were collected at each site using a high-volume sampler every 12 days from March 13th, 2018, to May 25th, 2019. The collection media consisted of a quartz fiber filter (QFF) and a glass thimble containing polyurethane foam (PUF) and XAD-4 resin that collected particulate- and gas-phase PAHs. Approximately 288 m3 of ambient air was drawn over 24 h. The QFF and sorbents were extracted together in an accelerated solvent extraction (ASE) system, and the extract was then nitrogen blown down to 1 ml in an automatic evaporator, and the final extract was analyzed for 32 target PAHs on a gas chromatography/mass spectrometry (GC/MS) system operated in the select-ion-monitoring (SIM) mode. The US Environmental Protection Agency (EPA) reviewed and approved the sampling and analytical protocols. The dataset also has site descriptions, sampling information, and analytical performance. This PAH dataset can be used to explore atmospheric chemistry and sources of PAHs, estimate population exposures to airborne PAHs and the associated health risks, and address environmental health disparities.

Source apportionment based on lead isotope ratios: Could domestic dog's blood lead be used to identify the level and sources of lead pollution in children?

Domestic dogs have been proved to be used as "sentinel organisms" to monitor human lead exposure. However, whether dogs' blood can be used to identify the levels and pollution source of children's lead exposure still needs evidence. To evaluate the potential use of domestic dogs' blood lead as an indicator of lead exposure levels and pollution source of children, accompanying with potential environmental media samples, lead concentrations and isotope ratios (expressed as 207Pb/206Pb, 208Pb/206Pb) in blood were investigated and compared between children and dogs, who came from a Pb-Zn smelter area, a coal fired area and a control area without industrial activity. The results showed that there were significant correlations in blood lead levels (BLLs) between children and dogs in the study areas (p < 0.01). The lead isotope ratios (LIRs) in blood of children and dogs were disparate among the three areas, however, the LIRs of dogs were quite correlated with those of children in each area (p < 0.01). With the comparison of LIRs between potential pollution sources (slag, ore, coal, paint) and blood samples, the identified lead sources based on dogs' blood were found to be coincident with those based on children's blood. Ore smelting and coal combustion were the main sources of lead exposure for the dogs and children in the smelting area, and coal combustion was the predominant source for the children and dogs living in the coal burning area and control area. The results showed that dogs' BLLs might be used to estimate children's BLLs, and blood LIRs measurements of dogs' could be used as an alternative for identifying the sources of children's lead exposure. This study further provided relevant evidence for dogs to be sentinels exposed to human lead exposure and an alternative method for source apportionment of children's lead exposure.

Racial Disparities in the Heavy Metal Contamination of Urban Soil in the Southeastern United States.

(1) Background: Field monitoring data for addressing the disproportional burden of exposure to soil contamination in communities of minority and low socioeconomic status (SES) are sparse. This study aims to examine the association between soil heavy metal levels, SES, and racial composition. (2) Methods: A total of 423 soil samples were collected in the urban areas of eight cities across six Southern states in the U.S., in 2015. Samples were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS) for eight heavy metals. The association was examined with mixed models with the log-transformed metal concentrations as the dependent variables and rankings of low-income or minority percentages as the explanatory variables. (3) Results: Model results showed that soil metal concentrations were significantly associated with rankings of poverty and minority percentages. The cadmium concentration significantly increased by 4.7% (p-value < 0.01), for every 10 percentiles of increase in poverty rank. For every 10 percentiles of increase in minority rank, the soil concentrations were significantly up (p-values < 0.01) for arsenic (13.5%), cadmium (5.5%), and lead (10.6%). Minority rank had significant direct effects on both arsenic and lead. (4) Conclusions: The findings confirmed elevated heavy metal contamination in urban soil in low-income and/or predominantly minority communities.

Distributions and determinants of time spent outdoors among school-age children in China.

BACKGROUND: The outdoor time is a key factor that determines children's exposure to environmental contaminants. Meanwhile, children reap numerous physical and mental health benefits from playing outdoors. OBJECTIVE: This study aimed to characterize the distributions and identify determinants of the time spent outdoors among school-age children in China. METHODS: The study recruited 41,439 children aged 6-17 years in Mainland China using a multi-stage cluster random sampling method. This sample was nationally representative with sample weights created to account for the complex survey design. Information on time-activity patterns were collected with a standard questionnaire through face-to-face interviews. Frequency distributions of time outdoors were created by age group, gender, region, and other sociodemographic factors with sample weights. The key factors influencing time outdoors were identified using multivariable linear regression models. RESULTS: The grand mean (±standard deviation) time outdoors was 101 ± 51 min/day for all the study participants, 22.3% having <60 min/day. Children spent longer time outdoors in warm seasons and on weekends. Children's outdoor time was significantly influenced by gender, age, urbanicity, region, annual total household expenditure, building environment, and meteorological conditions (annual mean temperature, sunshine time, and precipitation). Girls, 15-17 year old, and urban children had 6 min/day, 8 min/day, and 13 min/day less outdoor time than boys, 6-8 year old, and rural children, respectively. Most significantly, urban girls and high school students had the shortest outdoor time. The cement ground was the most important type of ground for children playing outside. SIGNIFICANCE: This was the first national-scale study that characterized the time outdoors and where is it spent among school-age children in China. It revealed that one-fifth of Chinese children spent less than one hour outdoors every day, and urban girls had particular "indoor tendencies". The findings provide bases for future interventions and guidelines aimed at promoting children's physical activities.

Identification of origins and influencing factors of environmental odor episodes using trajectory and proximity analyses.

It is challenging for the governmental agencies to provide an instant response and to systematically analyze the huge number of odor complaints which are received frequently by them. This study aimed to establish a data analysis framework featuring trajectory and proximity analyses to confirm odor origins, assess impact areas, and identify determinants and mechanisms of odor episodes based on odor reports. The investigation used 273 odor complaints reported in northern Collierville, Tennessee, between January 1st, 2019 and December 15th, 2020. The location of each complaint was geocoded in Google Map, and the backward wind trajectories were calculated using the web-based Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. The nearby Eplex Landfill and Collierville Northwest Sewage Treatment Plant were targeted for the analyses. Odor impacts were evaluated with temporal and spatial characteristics of reported odor episodes. Logistic models were performed to identify weather parameters that significantly influenced odor occurrence. The field inspections indicated two periods targeting different sources. Period 1: from January 1st, 2019 to October 31st, 2020, the landfill appeared as the major source; Period 2: from November 1st, 2020 to December 15th, 2020, the sewage plant emerged as the major source. In Period 1, 65% of the complaints had wind transporting from the landfill, and 88% occurred at residences within 500 m of the landfill. In Period 2, 33% of the complaints had wind that blew from the sewage plant and 85% occurred at residences within 1000 m from the sewage plant. The likelihood of an odor episode day was significantly associated with wind speed [Odds Ratio (OR) = 0.66, 95% Confidence Interval (CI): 0.56-0.77], temperature (OR = 0.97, 95% CI: 0.95-0.98), and rainfall (OR = 1.02, 95% CI: 1.00-1.04). The odor issue in Collierville reflected poor zoning between the odor sources and residential areas. Separation distances of 500 m and 1000 m from the landfill and sewage facilities, respectively, are suggested to prevent odor issues. The proposed data analysis framework can be adopted by governmental agencies for fast responses to odor complaints, odor assessment, and environmental odor management.

Characteristics, sources, and health risks of PM2.5-bound trace elements in representative areas of Northern Zhejiang Province, China.

This study aimed to characterize PM2.5-bound trace elements in Northern Zhejiang Province (NZP), one of the most economically prosperous regions in China, and assess the associated health risks for the general populations. A year-long sampling campaign was conducted at four sites representative of urban, suburban, and rural areas of NZP. The average of the sum of twenty trace elements in PM2.5 was 2.8 ± 0.4 µg m-3, dominated by K, Al, Fe, Mg, Zn, and V (>100 ng m-3). The highest total elements' concentration occurred in winter, followed by autumn, spring, and summer. Enrichment factors and principal component analysis (PCA) revealed that the major sources of trace elements in NZP were fossil fuel combustion, biomass burning, crustal dust, traffic, and industrial emissions. Elevated concentrations of certain elements reflected featured sources in different areas, e.g., V and Ni from heavy oil combustion in the port city, and Cu, Fe and Ba from traffic emissions in urban areas. Arsenic (As) represented the major non-cancer risk driver as its hazard quotient was 8.7. The cumulative cancer risk from all the carcinogenic elements was 1.7 × 10-3 in NZP, exceeding the upper limit (10-4) of the acceptable risk range. As and Cr contributed 33% and 66%, respectively, and thus were regarded as cancer risk drivers. The high health risks from PM2.5-bound elements warrant future actions to control their emissions in this region. Priorities should target industrial operations and coal combustion emissions, as informed by the risk drivers.

Household Exposure to Secondhand Smoke among Chinese Children: Status, Determinants, and Co-Exposures.

Smoking prevalence stays high among adults in China, which also makes children exposed to secondhand smoke (SHS) in their households. This study aimed to investigate the status of SHS exposure among Chinese children, identify the influencing factors, and determine "co-exposure" to tobacco and other smokes in households. A total of 41,439 children aged 6-17 years were recruited from 30 provinces in Mainland China through the first Chinese Environmental Exposure-Related Human Activity Model Survey for Children (CEERHAPS-C). Information regarding children's demographics, socioeconomic status, and exposures to SHS and solid fuel smoke (SFS) in households was collected using a comprehensive questionnaire. Factors that affected exposures to household smokes were identified using multivariable logistic regressions. The overall prevalence of household SHS exposure was 41.7%, and the average duration was 14.7 ± 14.6 min/day among the exposed participants. Prevalence of household SHS exposure increased among children in older age groups and with parents in lower education levels. Among SHS-exposed children, 34% had co-exposure to SFS, and they had a significantly higher risk of co-exposure than non-SHS exposed children (odds ratio = 1.12, 95% confidence interval: 1.061, 1.162). The prevalence of household SHS exposure remains high among school-age children, suggesting the need to develop and implement smoking-free home programs.

Impacts of Independence Day fireworks on pollution levels of atmospheric polycyclic aromatic hydrocarbons (PAHs) in the U.S.

Fireworks on Independence Day have been identified as a nationwide but short-term source of particulate matter in the U.S. No study has specifically examined their impacts on ambient polycyclic aromatic hydrocarbons (PAHs). Based on data between 1990 and 2019 in the Air Quality System, we identified 76 unique events that had PAH measurements on both July 4th days and control days (within 15 days before and after July 4th). We compared concentrations and diagnostic ratios of 16 priority PAHs between event and control days using Wilcoxon signed-rank tests and multivariable regressions. A local PAH monitoring campaign was conducted at eight sites in Memphis, Tennessee, to obtain a close observation of PAH changes. The national geometric mean (GM) concentrations of summed 16 PAHs (ΣPAHs) were similar between event and control days (48.1 ng/m3 vs. 52.8 ng/m3, p = 0.98). About a quarter of events had elevated PAH concentrations compared with control days. Higher diagnostic ratios were found on event days, suggesting more contributions from fireworks sources. PAHs on July 4th were unlikely to cause acute or chronic health effects. While the local monitoring showed a 15% increase of ΣPAHs on July 4th, the difference was not significant (p = 0.62). Elevated PAH concentrations occurred at sites near fireworks sources and without major traffics, but did not occur at those in remote areas or near major interstate highways. In conclusion, this study finds that Independence Day fireworks have negligible impacts on atmospheric PAHs at the national level, and are unlikely to pose significant health risks. The firework effect is localized within a limited geographic scale, suggesting potential needs for local monitoring and control programs.

Association between exposure to fine particulate matter and obesity in children: A national representative cross-sectional study in China.

BACKGROUND: Childhood obesity is a global health issue, and limited evidence suggests that air pollution may be a contributing factor. This study aims to examine whether exposure to fine particulate matter (PM2.5) is associated with obesity status in a nationally representative sample of schoolchildren in China. METHODS: The study population consisted of 41,439 schoolchildren of 6-17 years old, recruited from 30 provinces in China using a multi-stage stratified sampling method. Weights and heights were measured for all the participants, and sociodemographic information was collected using a questionnaire. The obesity status was classified following the Chinese national standards. The PM2.5 exposure was estimated as the 5-year average concentration at the school location for each participant. The association between obesity status and PM2.5 exposure was examined using weighted logistic regressions adjusted for potential confounders. RESULTS: The prevalence of normal weight, overweight, and obesity were 78.5%, 12.4%, and 9.0%, respectively. PM2.5 exposure averaged 59.8 ± 17.6 µg/m3 with a range of 30.5-115.2 µg/m3 among all the participants. The risk of obesity increased by 10.0% (95% confidence interval: 3.0-16.0%) per 10 µg/m3 increase in PM2.5 exposure. The PM2.5-associated risk was significantly elevated in older age groups and children living in urban areas (interaction p-values < 0.05). CONCLUSIONS: This national survey revealed that approximately 1 in 5 Chinese schoolchildren were overweight or obese. Exposure to PM2.5 in the ambient air was significantly associated with childhood obesity. The findings suggest the need for further research to uncover the roles of PM2.5 exposure in childhood obesity development.

Association between milk intake and childhood growth: results from a nationwide cross-sectional survey.

PURPOSE: The literature is inconsistent regarding milk intake and physical growth. This study aims to evaluate the association of milk intake with body height and weight in a nationally representative sample of Chinese children. METHODS: A total of 41,439 children ages 6-17 were recruited from 30 provinces in mainland China in 2013-2016 using a multistage stratified cluster sampling approach. Milk intake information was collected using a questionnaire aided with standard containers. Weight and height were measured using a standard physician beam scale with a height rod. Milk intake was categorized into no-, low-, and high-intake groups based on the intake rate, and weight status into normal, overweight, and obese groups based on the body-mass-index (BMI). Associations between height/weight status and milk intake were evaluated using multivariate weighted linear and logistic regression models. RESULTS: Chinese children had low milk intake: 1/5 of children did not drink milk, and those drinking milk had a median intake of 100 ml/month. The low- and high-intake groups were 0.83 cm (95% confidence interval: 0.00, 1.68 cm) and 1.26 cm (0.34, 2.19 cm) taller than the no-intake group for girls, respectively, after adjusting for confounding factors. Boys with high milk intake had lower BMI (-0.56, 95% CI: -1.00, -0.12 kg/m2) and risk of obesity (OR = 0.67, 95% CI: 0.46, 0.97) than those without milk intake. CONCLUSIONS: This study revealed the association of increased milk intake with increased body height and lowered obesity risk among Chinese children. Given the cross-sectional nature of the study and the possibility of residual confounding, further research is warranted to uncover the role of milk intake in promoting children's growth.

Patterns and sociodemographic determinants of water intake by children in China: results from the first national population-based survey.

PURPOSE: Accurate data on water and beverage intakes are essential for assessing hydration adequacy and setting proper guidelines. The objective of this study is to identify the patterns and sociodemographic determinants of water intake and to assess the intake adequacy for children in China. METHODS: The study team recruited 41,439 children aged 6-17 years using a multi-stage cluster random sampling method. Daily water and beverage intakes were investigated with the standard questionnaires and measuring containers in face-to-face interviews. Each participant was assigned an adjustment weight to obtain a nationally representative sample. Sociodemographic factors influencing water intake were identified using multi-variable regressions. Water intake adequacy was evaluated by comparing with the recommended water intake (RWI). RESULTS: The mean ± standard deviation of total water intake (TWI) was 1603 ± 731 mL/day for boys and 1487 ± 661 mL/day for girls. Plain water, food moisture, and other beverages contributed 51%, 20%, and 29% of the TWI. Multi-variable analyses showed that TWI of children increased with age, in urban areas and day schools, and with parents' economic and educational levels. The majority (82%) of children had TWI not meeting the corresponding RWI, and the percentage increased with age except for 14-17-year-old boys. CONCLUSIONS: Plain water is still the major source of daily water intake by children in China. Unfortunately, the majority of children do not have sufficient water intake, which warrants future actions and guidelines targeting adequate hydration.

Efficacy of Acupuncture Combined with Local Anesthesia in Ischemic Stroke Patients with Carotid Artery Stenting: A Prospective Randomized Trial.

OBJECTIVE: To evaluate the efficacy of electro-acupuncture (EA) or transcutaneous electrical acupoint stimulation (TEAS) on perioperative cerebral blood flow (CBF) and neurological function in ischemic stroke (IS) patients undergoing carotid artery stenting (CAS). METHODS: In total, 124 consecutive IS patients were randomly allocated to the EA, TEAS, and sham groups (groups A, T, and S; 41, 42, and 41 cases, respectively) by software-derived random-number sequence. Groups A and T received EA and TEAS, respectively, at the Shuigou (GV 26) and Baihui (GV 20), Hegu (LI4) and Waiguan (TE 5) acupoints. Group S received sham EA. The stimulation was started from 30 min before surgery until the end of the operation. The primary outcome was the CBF at 30 min after surgery, which was measured by transcranial Doppler sonography. The secondary outcomes included hyperperfusion incidence and neurological function. National Institutes of Health Stroke Scale (NIHSS) and General Evaluation Scale (GES) scores were recorded at 1 week, 1 month, and 3 months postoperatively. RESULTS: Mean CBF velocity at 30 min after surgery in groups A and T was much lower than that in Group S (P < 0.05); the incidence of hyperperfusion in Groups A and T was also lower than that in group S (P <0.05). Acupuncture was an independent factor associated with reduced incidence of hyperperfusion (OR=0.042; 95% CI: 0.002-0.785; =0.034). NIHSS and GES scores improved significantly at 1 week postoperatively in Groups A and T than in Group S (P < 0.05). Relative to Group S, groups A and T exhibited significantly lower incidences of moderate pain, as well as higher incidences of satisfaction with anesthesia, at 1 day postoperatively (P < 0.05). CONCLUSIONS: EA or TEAS administered in combination with local anesthesia during CAS can inhibit transient increases in CBF, reduce the incidence of postoperative hyperperfusion, and improve neurological function. (Registration No. ChiCTR-IOR-15007447).

Variability of Total Volatile Organic Compounds (TVOC) in the Indoor Air of Retail Stores.

Volatile organic compounds (VOCs) are released to the indoor air of retail stores from numerous products and activities, but available literature lacks a systematic understanding of the variability of VOC concentrations. In this study, we measured concentrations of total VOCs (TVOC) in 32 retail stores using a high-sensitivity photoionization detector (PID). Indoor thermal comfort parameters, including temperature, relative humidity, and air velocity, were simultaneously measured using an anemometer. The store-level TVOC concentrations ranged from 30 to 869 ppb and exceeded the LEED guideline in 31 stores. TVOC levels were notably high in hardware stores (median = 536 ppb, p = 0.0002) and paints, household, and home accessories sections within stores (p < 0.05). TVOC levels were elevated in mornings and evenings, possibly due to low ventilation and cleaning activities at the beginning and end of business hours. The between-store, within-store, and temporal variations accounted for 85%, 0.5%, and 14% of the total variance, respectively. The variance structure suggested that in-store VOC concentrations were predominantly driven by their source location, and representative monitoring should first consider covering various store types. Current store VOC levels present health concerns, but further studies are needed to evaluate risks among customers.

Heatwave Events and Mortality Outcomes in Memphis, Tennessee: Testing Effect Modification by Socioeconomic Status and Urbanicity.

Heatwave studies typically estimate heat-related mortality and morbidity risks at the city level; few have addressed the heterogeneous risks by socioeconomic status (SES) and location within a city. This study aimed to examine the impacts of heatwaves on mortality outcomes in Memphis, Tennessee, a Mid-South metropolitan area top-ranked in morbidity and poverty rates, and to investigate the effects of SES and urbanicity. Mortality data were retrieved from the death records in 2008-2017, and temperature data from the Applied Climate Information System. Heatwave days were defined based on four temperature metrics. Heatwave effects on daily total-cause, cardiovascular, and respiratory mortality were evaluated using Poisson regression, accounting for temporal trends, sociodemographic factors, urbanicity, and air pollution. We found higher cardiovascular mortality risk (cumulative RR (relative risk) = 1.25, 95% CI (confidence interval): 1.01-1.55) in heatwave days defined as those with maximum daily temperature >95th percentile for more than two consecutive days. The effects of heatwaves on mortality did not differ by SES, race, or urbanicity. The findings of this study provided evidence to support future heatwave planning and studies of heatwave and health impacts at a coarser geographic resolution.

Biomass burning and fungal spores as sources of fine aerosols in Yangtze River Delta, China - Using multiple organic tracers to understand variability, correlations and origins.

Research is restricted regarding impacts of biomass burning (BB) on fine aerosol (PM2.5), due mainly to lack of specific BB tracers. This study aims to characterize the variability, distributions, and contributions of BB and fungal spores as sources of PM2.5 using a multiple organic tracer approach. PM2.5 samples were collected at four representative sites in Yangtze River Delta (YRD), China every 6 days for one year. In the laboratory, samples were analyzed for three anhydrides (levoglucosan, mannosan, and galactosan), two sugar alcohols (arabitol and mannitol), water-soluble inorganic ions, and elemental/organic carbon (EC/OC). Levoglucosan was the most abundant BB tracer (mean concentration = 81 ng/m3), and fungal spore tracers arabitol and mannitol had similar abundances (5.6 and 5.7 ng/m3, respectively). Anhydrides and sugar alcohols had high within-group correlations, indicating their respective common sources. Concentrations of tracers displayed large temporal variations but small spatial variations, suggesting strong seasonality in BB and fungal spore sources. BB sources were burning of grass, pine needles, hardwood and crop straw, which were originated from transboundary/cross-region transport and local fire spots. PCA analyses revealed that the common sources of fine aerosols in YRD were secondary inorganic aerosols, soil dust, BB and fungal spores.