Fifteen-year trends in criteria air pollutants in oil sands communities of Alberta,Canada

An investigation of ambient air quality was undertaken at three communities within the Athabasca Oil Sands Region (AOSR) of Alberta, Canada (Fort McKay, Fort McMurray, and Fort Chipewyan). Daily and seasonal patterns and 15-year trends were investigated for several criteria air pollutants over the period of 1998 to 2012. A parametric trend detection method using percentiles from frequency distributions of 1 h concentrations for a pollutant during each year was used. Variables representing 50th, 65th, 80th, 90th, 95th and 98th percentile concentrations each year were identified from frequency distributions and used for trend analysis. Small increasing concentration trends were observed for nitrogen dioxide (< 1 ppb/year) at Fort McKay and Fort McMurray over the period consistent with increasing emissions of oxides of nitrogen (ca. 1000 tons/year) from industrial developments. Emissions from all oil sands facilities appear to be contributing to the trend at Fort McKay, whereas both emissions from within the community (vehicles and commercial) and oil sands facility emissions appear to be contributing to the trend at Fort McMurray. Sulfur dioxide (SO₂) emissions from industrial developments in the AOSR were unchanged during the period (101,000 ± 7000 tons/year; mean ± standard deviation) and no meaningful trends were judged to be occurring at all community stations. No meaningful trends occurred for ozone and fine particulate matter (PM_2.5) at all community stations and carbon monoxide at one station in Fort McMurray. Air quality in Fort Chipewyan was much better and quite separate in terms of absence of factors influencing criteria air pollutant concentrations at the other community stations.     

Evaluation of air quality indicators in Alberta,Canada – An international perspective

There has been an increase in oil sands development in northern Alberta, Canada and an overall increase in economic activity in the province in recent years. An evaluation of the state of air quality was conducted in four Alberta locations – urban centers of Calgary and Edmonton, and smaller communities of Fort McKay and Fort McMurray in the Athabasca Oil Sands Region (AOSR). Concentration trends, diurnal hourly and monthly average concentration profiles, and exceedances of provincial, national and international air quality guidelines were assessed for several criteria air pollutants over the period 1998 to 2014. Two methods were used to evaluate trends. Parametric analysis of annual median 1 h concentrations and non-parametric analysis of annual geometric mean 1 h concentrations showed consistent decreasing trends for NO₂ and SO₂ (< 1 ppb per year), CO (< 0.1 ppm per year) at all stations, decreasing for THC (< 0.1 ppm per year) and increasing for O₃ (≤ 0.52 ppb per year) at most stations and unchanged for PM_2.5 at all stations in Edmonton and Calgary over a 17-year period. Little consistency in trends was observed among the methods for the same air pollutants other than for THC (increasing in Fort McKay < 0.1 ppm per year and no trend in Fort McMurray), PM_2.5 in Fort McKay and Fort McMurray (no trend) and CO (decreasing < 0.1 ppm per year in Fort McMurray) over the same period. Levels of air quality indicators at the four locations were compared with other Canadian and international urban areas to judge the current state of air quality. Median and annual average concentrations for Alberta locations tended to be the smallest in Fort McKay and Fort McMurray. Other than for PM_2.5, Calgary and Edmonton tended to have median and annual average concentrations comparable to and/or below that of larger populated Canadian and U.S. cities, depending upon the air pollutant.     

Contribution of post-harvest agricultural paddy residue fires in the N.W. Indo-Gangetic Plain to ambient carcinogenic benzenoids,toxic isocyanic acid and carbon monoxide

In the north west Indo-Gangetic Plain (N.W.IGP), large scale post-harvest paddy residue fires occur every year during the months of October–November. This anthropogenic perturbation causes contamination of the atmospheric environment with adverse impacts on regional air quality posing health risks for the population exposed to high concentrations of carcinogens such as benzene and toxic VOCs such as isocyanic acid. These gases and carbon monoxide are known to be emitted from biomass fires along with acetonitrile. Yet no long-term in-situ measurements quantifying the impact of this activity have been carried out in the N.W. IGP. Using high quality continuous online in-situ measurements of these gases at a strategic downwind site over a three year period from 2012 to 2014, we demonstrate the strong impact of this anthropogenic emission activity on ambient concentrations of these gases. In contrast to the pre-paddy harvest period, excellent correlation of benzenoids, isocyanic acid and CO with acetonitrile (a biomass burning chemical tracer); (r ≥ 0.82) and distinct VOC/acetonitrile emission ratios were observed for the post-paddy harvest period which was also characterized by high ambient concentrations of these species. The average concentrations of acetonitrile (1.62 ± 0.18 ppb), benzene (2.51 ± 0.28 ppb), toluene (3.72 ± 0.41 ppb), C8-aromatics (2.88 ± 0.30 ppb), C9-aromatics (1.55 ± 0.19 ppb) and CO (552 ± 113 ppb) in the post-paddy harvest periods were about 1.5 times higher than the annual average concentrations. For isocyanic acid, a compound with both primary and secondary sources, the concentration in the post-paddy harvest period was 0.97 ± 0.17 ppb. The annual average concentrations of benzene, a class A carcinogen, exceeded the annual exposure limit of 1.6 ppb at NTP mandated by the National Ambient Air Quality Standard of India (NAAQS). We show that mitigating the post-harvest paddy residue fires can lower the annual average concentration of benzene and ensure compliance with the NAAQS. Calculations of excessive lifetime cancer risk due to benzene amount to 25 and 10 per million inhabitants for children and adults, respectively, exceeding the USEPA threshold of 1 per million inhabitants. Annual exposure to isocyanic acid was close to 1 ppb, the concentration considered to be sufficient to enhance risks for cardiovascular diseases and cataracts. This study makes a case for urgent mitigation of post-harvest paddy residue fires as the unknown synergistic effect of multi-pollutant exposure due to emissions from this anthropogenic source may be posing grave health risks to the population of the N.W. IGP.     

Short-term effects of air pollution on respiratory morbidity at Rio de Janeiro — Part II: Health assessment

The effects of air pollution on health have been studied worldwide. Given that air pollution triggers oxidative stress and inflammation, it is plausible that high levels of air pollutants cause higher number of hospitalisations. This study aimed to assess the impact of air pollution on the emergency hospitalisation for respiratory disease in Rio de Janeiro, Brazil. The study was divided in two parts: Part I specifically addressing the air pollution assessment and Part II addressing the health assessment. Accordingly, this Part II aimed to estimate the association between the concentrations of PM₁₀, SO₂ and CO observed in Rio de Janeiro and the number of emergency hospitalisations at a central hospital due to respiratory diseases. The pollutant concentrations were measured at two different sites in Rio de Janeiro, but the excess relative risks were calculated based on the concentrations observed at one of the sites, where limits were generally exceeded more frequently, between September 2000 and December 2005. A time series analysis was performed using the number of hospitalisations, divided in three categories (children until 1 year old, children aged between 1 and 5 years old and elderly with 65 years old or more) as independent variable, the concentrations of pollutants as dependent variables and temperature, relative humidity, long term trend, and seasonality as confounders. Data were analysed using generalised additive models with smoothing for some of the dependent variables. Results showed an excess risk of hospitalisation for respiratory disease higher than 2% per 10 μg m^− 3 increase in PM₁₀ concentrations for children under 5 years old, of 2% per 10 μg m^− 3 increase in SO₂ for elderly above 65 years old and around 0.1% per 10 μg m^− 3 increase in CO for children under 1 year and elderly. Other studies have found associations that are in agreement with the results achieved in this study.The study suggests that the ambient levels of air pollutants experienced in Rio de Janeiro between 2000 and 2005 were linked to the number of hospitalisations for respiratory diseases among children and elderly.     

Associations between PBDEs in office air,dust, and surface wipes

Increased use of flame-retardants in office furniture may increase exposure to PBDEs in the office environment. However, partitioning of PBDEs within the office environment is not well understood. Our objectives were to examine relationships between concurrent measures of PBDEs in office air, floor dust, and surface wipes.We collected air, dust, and surface wipe samples from 31 offices in Boston, MA. Correlation and linear regression were used to evaluate associations between variables. Geometric mean (GM) concentrations of individual BDE congeners in air and congener specific octanol–air partition coefficients (K_oa) were used to predict GM concentrations in dust and surface wipes and compared to the measured concentrations.GM concentrations of PentaBDEs in office air, dust, and surface wipes were 472 pg/m³, 2411 ng/g, and 77 pg/cm², respectively. BDE209 was detected in 100% of dust samples (GM = 4202 ng/g), 93% of surface wipes (GM = 125 pg/cm²), and 39% of air samples. PentaBDEs in dust and air were moderately correlated with each other (r = 0.60, p = 0.0003), as well as with PentaBDEs in surface wipes (r = 0.51, p = 0.003 for both dust and air). BDE209 in dust was correlated with BDE209 in surface wipes (r = 0.69, p = 0.007). Building (three categories) and PentaBDEs in dust were independent predictors of PentaBDEs in both air and surface wipes, together explaining 50% (p = 0.0009) and 48% (p = 0.001) of the variation respectively. Predicted and measured concentrations of individual BDE congeners were highly correlated in dust (r = 0.98, p < 0.0001) and surface wipes (r = 0.94, p = 002). BDE209 provided an interesting test of this equilibrium partitioning model as it is a low volatility compound.Associations between PentaBDEs in multiple sampling media suggest that collecting dust or surface wipes may be a convenient method of characterizing exposure in the indoor environment. The volatility of individual congeners, as well as physical characteristics of the indoor environment, influence relationships between PBDEs in air, dust, and surface wipes.     

Measurement and health risk assessment of PM2.5, flame retardants,carbonyls and black carbon in indoor and outdoor air in kindergartens in Hong Kong

Indoor air pollution is closely related to children's health. Polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DP) transmitted through indoor PM_2.5 and dust, along with carbonyl compounds and black carbon (BC) aerosol were analysed in five Hong Kong kindergartens. The results showed that 60% of the median PM_2.5 levels (1.3 × 10¹ to 2.9 × 10¹ μg/m³ for indoor; 9.5 to 8.8 × 10¹ μg/m³ for outdoor) in the five kindergartens were higher than the guidelines set by the World Health Organization (2.5 × 10¹ μg/m³). Indoor PM_2.5 mass concentrations were correlated with outdoor PM_2.5 in four of the kindergartens. The PBDEs (0.10–0.64 ng/m³ in PM_2.5; 0.30–2.0 × 10² ng/g in dust) and DP (0.05–0.10 ng/m³ in PM_2.5; 1.3–8.7 ng/g in dust) were detected in 100% of the PM_2.5 and dust samples. Fire retardant levels in the air were not correlated with the levels of dust in this study. The median BC concentrations varied by > 7-fold from 8.8 × 10² ng/m^− 3 to 6.7 × 10³ ng/m^− 3 and cooking events might have caused BC concentrations to rise both indoors and outdoors. The total concentrations of 16 carbonyls ranged from 4.7 × 10¹ μg/m³ to 9.3 × 10¹ μg/m³ indoors and from 1.9 × 10¹ μg/m³ to 4.3 × 10¹ μg/m³ outdoors, whilst formaldehyde was the most abundant air carbonyl. Indoor carbonyl concentrations were correlated with outdoor carbonyls in three kindergartens. The health risk assessment showed that hazard indexes (HIs) HIs of non-cancer risks from PBDEs and DPs were all lower than 0.08, whilst non-cancer HIs of carbonyl compounds ranged from 0.77 to 1.85 indoors and from 0.50 to 0.97 outdoors. The human intake of PBDEs and DP through inhalation of PM_2.5 accounted for 78% to 92% of the total intake. The cancer hazard quotients (HQs) of formaldehyde ranged from 4.5E − 05 to 2.1E − 04 indoors and from 1.9E − 05 to 6.2E − 05 outdoors. In general, the indoor air pollution in the five Hong Kong kindergartens might present adverse effects to children, although different schools showed distinct pollution levels, so indoor air quality might be improved through artificial measures. The data will be useful to developing a feasible management protocol for indoor environments.     

Associations among plasma metabolite levels and short-term exposure to PM2.5 and ozone in a cardiac catheterization cohort

RationaleExposure to ambient particulate matter (PM) and ozone has been associated with cardiovascular disease (CVD). However, the mechanisms linking PM and ozone exposure to CVD remain poorly understood.ObjectiveThis study explored associations between short-term exposures to PM with a diameter < 2.5 μm (PM_2.5) and ozone with plasma metabolite concentrations.Methods and resultsWe used cross-sectional data from a cardiac catheterization cohort at Duke University, North Carolina (NC), USA, accumulated between 2001 and 2007. Amino acids, acylcarnitines, ketones and total non-esterified fatty acid plasma concentrations were determined in fasting samples. Daily concentrations of PM_2.5 and ozone were obtained from a Bayesian space-time hierarchical model, matched to each patient's residential address. Ten metabolites were selected for the analysis based on quality criteria and cluster analysis. Associations between metabolites and PM_2.5 or ozone were analyzed using linear regression models adjusting for long-term trend and seasonality, calendar effects, meteorological parameters, and participant characteristics.We found delayed associations between PM_2.5 or ozone and changes in metabolite levels of the glycine-ornithine-arginine metabolic axis and incomplete fatty acid oxidation associated with mitochondrial dysfunction. The strongest association was seen for an increase of 8.1 μg/m³ in PM_2.5 with a lag of one day and decreased mean glycine concentrations (− 2.5% [95% confidence interval: − 3.8%; − 1.2%]).ConclusionsShort-term exposures to ambient PM_2.5 and ozone is associated with changes in plasma concentrations of metabolites in a cohort of cardiac catheterization patients. Our findings might help to understand the link between air pollution and cardiovascular disease.     

Can car air filters be useful as a sampling medium for air pollution monitoring purposes?

Urban air quality and real human exposure to chemical environmental stressors is an issue of high scientific and political interest. In an effort to find innovative and inexpensive means for air quality monitoring, the ability of car engine air filters (CAFs) to act as efficient samplers collecting street level air, to which people are exposed to, was tested. In particular, in the case of taxis, air filters are replaced after regular distances, the itineraries are almost exclusively urban, cruising mode is similar and, thus, knowledge of the air flow can provide with an integrated city air sample. The present pilot study focused on polycyclic aromatic hydrocarbons (PAHs), the most important category of organic pollutants associated with traffic emissions. Concentrations of ΣPAHs in CAFs ranged between 650 and 2900 μg CAF^− 1, with benzo[b]fluoranthene, benzo[k]fluoranthene and indeno[123-cd]pyrene being the most abundant PAHs. Benzo[a]pyrene (BaP) ranged between 110 and 250 μg CAF^− 1, accounting regularly for 5–15% of the total carcinogenic PAHs. The CAF PAH loads were used to derive road-level atmospheric PAH concentrations from a standard formula relating to the CAF air flow. Important parameters/assumptions for these estimates are the cruising speed and the exposure duration of each CAF. Based on information obtained from the garage experts, an average ‘sampled air volume’ of 48,750 m³ per CAF was estimated, with uncertainty in this calculation estimated to be about a factor of 4 between the two extreme scenarios. Based on this air volume, ΣPAHs ranged between 13 and 56 ng m^− 3 and BaP between 2.1 and 5.0 ng m^− 3, suggesting that in-traffic BaP concentrations can be many times higher than the limit values set by the UK (0.25 ng m^− 3) and the European Union (1.0 ng m^− 3), or from active sampling stations normally cited on building roof tops or far from city centres.Notwithstanding the limitations of this approach, the very low cost, the continuous availability of very high amounts of “sample”, and the “retroactivity” render it very useful and complementary to existing passive sampling techniques. This approach yields estimated air concentrations that reflect the pollutant concentrations to which taxi drivers, pedestrians, cyclists and road-related professionals are exposed.     

Air pollution exposure increases the risk of rheumatoid arthritis: A longitudinal and nationwide study

ObjectiveRheumatoid arthritis (RA) has been associated with inhaled pollutants in several studies, and it is a disease of chronic inflammation. The association between air pollution and the risk of RA remains unclear. Therefore, we conducted this nationwide, retrospective, sex-stratification study to evaluate this association.MethodsWe collected data from the Longitudinal Health Insurance Database (LHID), maintained by the Taiwan Bureau of National Health Insurance, and the Taiwan Air Quality-Monitoring Database (TAQMD), released by the Taiwan Environmental Protection Agency. The TAQMD provides the daily concentrations of particulate matter with the aerodynamic diameter < 2.5 μm (PM_2.5) and nitrogen dioxide (NO₂) from 74 ambient air quality-monitoring stations distributed all over Taiwan during 1998–2010. The LHID and TAQMD were linked according to the residential areas of insurants and the areas where the air quality-monitoring stations were located. A residential area was defined according to the location of the clinic and hospital that treated acute upper respiratory tract infections. The yearly average air pollutant concentrations were categorized into 4 levels based on quartiles. We evaluated the risk of RA in residents exposed to 4 levels of PM_2.5 and NO₂ concentrations.ResultsWe detected an increased risk of RA in participants exposed to PM_2.5 and NO₂. Among four quartiles of NO₂ concentration, namely Q1, Q2, Q3, and Q4, the adjusted hazard ratios (aHRs) in Q2, Q3, and Q4 compared with that in Q1 were 1.07 (95% confidence interval [CI] = 0.76–1.50), 1.63 (95% CI = 1.16–2.31),and 1.49 (95% CI = 1.05–2.12), respectively. Regarding the PM_2.5 concentrations, the aHRs after exposure to the Q2, Q3, and Q4 levels were 1.22 (95% CI = 0.85–1.74), 1.15 (95% CI = 0.82–1.62), and 0.79 (95% CI = 0.53–1.16), respectively.ConclusionThe results of this nationwide study suggest an increased risk of RA in residents exposed to NO₂.     

Air pollutant exposure and preterm and term small-for-gestational-age births in Detroit,Michigan: Long-term trends and associations

Studies in a number of countries have reported associations between exposure to ambient air pollutants and adverse birth outcomes, including low birth weight, preterm birth (PTB) and, less commonly, small for gestational age (SGA). Despite their growing number, the available studies have significant limitations, e.g., incomplete control of temporal trends in exposure, modest sample sizes, and a lack of information regarding individual risk factors such as smoking. No study has yet examined large numbers of susceptible individuals.We investigated the association between ambient air pollutant concentrations and term SGA and PTB outcomes among 164,905 singleton births in Detroit, Michigan occurring between 1990 and 2001. SO₂, CO, NO₂, O₃ and PM₁₀ exposures were used in single and multiple pollutant logistic regression models to estimate odds ratios (OR) for these outcomes, adjusted for the infant's sex and gestational age, the mother's race, age group, education level, smoking status and prenatal care, birth season, site of residence, and long-term exposure trends.Term SGA was associated with CO levels exceeding 0.75 ppm (OR = 1.14, 95% confidence interval = 1.02–1.27) and NO₂ exceeding 6.8 ppb (1.11, 1.03–1.21) exposures in the first month, and with PM₁₀ exceeding 35 μg/m³ (1.22, 1.03–1.46) and O₃ (1.11, 1.02–1.20) exposure in the third trimester. PTB was associated with SO₂ (1.07, 1.01–1.14) exposure in the last month, and with (hourly) O₃ exceeding 92 ppb (1.08, 1.02–1.14) exposure in the first month.Exposure to several air pollutants at modest concentrations was associated with adverse birth outcomes. This study, which included a large Black population, suggests the importance of the early period of pregnancy for associations between term SGA with CO and NO₂, and between O₃ with PTB; and the late pregnancy period for associations between term SGA and O₃ and PM₁₀, and between SO₂ with PTB. It also highlights the importance of accounting for individual risk factors such as maternal smoking, maternal race, and long-term trends in air pollutant levels and adverse birth outcomes in evaluating relationships between pollutant exposures and adverse birth outcomes.     

Cause-specific premature death from ambient PM2.5 exposure in India: Estimate adjusted for baseline mortality

In India, more than a billion population is at risk of exposure to ambient fine particulate matter (PM_2.5) concentration exceeding World Health Organization air quality guideline, posing a serious threat to health. Cause-specific premature death from ambient PM_2.5 exposure is poorly known for India. Here we develop a non-linear power law (NLP) function to estimate the relative risk associated with ambient PM_2.5 exposure using satellite-based PM_2.5 concentration (2001 − 2010) that is bias-corrected against coincident direct measurements. We show that estimate of annual premature death in India is lower by 14.7% (19.2%) using NLP (integrated exposure risk function, IER) for assumption of uniform baseline mortality across India (as considered in the global burden of disease study) relative to the estimate obtained by adjusting for state-specific baseline mortality using GDP as a proxy. 486,100 (811,000) annual premature death in India is estimated using NLP (IER) risk functions after baseline mortality adjustment. 54.5% of premature death estimated using NLP risk function is attributed to chronic obstructive pulmonary disease (COPD), 24.0% to ischemic heart disease (IHD), 18.5% to stroke and the remaining 3.0% to lung cancer (LC). 44,900 (5900–173,300) less premature death is expected annually, if India achieves its present annual air quality target of 40 μg m^− 3. Our results identify the worst affected districts in terms of ambient PM_2.5 exposure and resulting annual premature death and call for initiation of long-term measures through a systematic framework of pollution and health data archive.     

Blood pressure changes in association with black carbon exposure in a panel of healthy adults are independent of retinal microcirculation

Exposure to ambient particulate matter and elevated blood pressure are risk factors for cardiovascular morbidity and mortality. Microvascular changes might be an important pathway in explaining the association between air pollution and blood pressure. The objective of the study was to evaluate the role of the retinal microcirculation in the association between black carbon (BC) exposure and blood pressure.We estimated subchronic BC exposure based on 1-week personal measurements (μ-Aethalometer, AethLabs) in 55 healthy nurses. Blood pressure and retinal microvasculature were measured on four different days (range: 2–4) during this week.Subchronic BC exposure averaged (± SD) 1334 ± 631 ng/m³ and ranged from 338 ng/m³ to 3889 ng/m³. An increased exposure of 631 ng/m³ BC was associated with a 2.77 mm Hg (95% CI: 0.39 to 5.15, p = 0.027) increase in systolic blood pressure, a 2.35 mm Hg (95% CI: 0.52 to 4.19, p = 0.016) increase in diastolic blood pressure and with 5.65 μm (95% CI: 1.33 to 9.96, p = 0.014) increase in central retinal venular equivalent. Mediation analysis failed to reveal an effect of retinal microvasculature in the association between blood pressure and subchronic BC exposure.In conclusion, we found a positive association between blood pressure and subchronic black carbon exposure in healthy adults. This finding adds evidence to the association between black carbon exposure and cardiovascular health effects, with elevated blood pressure as a plausible intermediate effector. Our results suggest that the changes in a person's blood pressure as a result of subchronic black carbon exposure operate independently of the retinal microcirculation.     

Spatiotemporal analysis and human exposure assessment on polycyclic aromatic hydrocarbons in indoor air,settled house dust,and diet: A review

This review summarizes the published literature on the presence of polycyclic aromatic hydrocarbons (PAH) in indoor air, settled house dust, and food, and highlights geographical and temporal trends in indoor PAH contamination. In both indoor air and dust, ΣPAH concentrations in North America have decreased over the past 30 years with a halving time of 6.7 ± 1.9 years in indoor air and 5.0 ± 2.3 years in indoor dust. In contrast, indoor PAH concentrations in Asia have remained steady. Concentrations of ΣPAH in indoor air are significantly (p < 0.01) higher in Asia than North America. In studies recording both vapor and particulate phases, the global average concentration in indoor air of ΣPAH excluding naphthalene is between 7 and 14,300 ng/m³. Over a similar period, the average ΣPAH concentration in house dust ranges between 127 to 115,817 ng/g. Indoor/outdoor ratios of atmospheric concentrations of ΣPAH have declined globally with a half-life of 6.3 ± 2.3 years. While indoor/outdoor ratios for benzo[a]pyrene toxicity equivalents (BaP_eq) declined in North America with a half-life of 12.2 ± 3.2 years, no significant decline was observed when data from all regions were considered. Comparison of the global database, revealed that I/O ratios for ΣPAH (average = 4.3 ± 1.3), exceeded significantly those of BaP_eq (average = 1.7 ± 0.4) in the same samples. The significant decline in global I/O ratios suggests that indoor sources of PAH have been controlled more effectively than outdoor sources. Moreover, the significantly higher I/O ratios for ΣPAH compared to BaP_eq, imply that indoor sources of PAH emit proportionally more of the less carcinogenic PAH than outdoor sources. Dietary exposure to PAH ranges from 137 to 55,000 ng/day. Definitive spatiotemporal trends in dietary exposure were precluded due to relatively small number of relevant studies. However, although reported in only one study, PAH concentrations in Chinese diets exceeded those in diet from other parts of the world, a pattern consistent with the spatial trends observed for concentrations of PAH in indoor air. Evaluation of human exposure to ΣPAH via inhalation, dust and diet ingestion, suggests that while intake via diet and inhalation exceeds that via dust ingestion; all three pathways contribute and merit continued assessment.     

Monocyclic and bicyclic monoterpenes in air of German daycare centers and human biomonitoring in visiting children,the LUPE 3 study

To investigate the assumed association between indoor air pollution with monoterpenes (MTps) and the internal MTp exposure of occupants, a comparative study was performed in daycare centers in two federal states of Germany. Three well-known monoterpenoid air pollutants, viz. α-pinene (αPN), Δ³-carene (CRN), and R-limonene (LMN), were measured in indoor air in 45 daycare centers. Additionally, urine samples of 222 children visiting these facilities were collected in the evening after a full-day stay. Altogether 11 MTp metabolites were analyzed in the urine samples using a novel highly sensitive and selective gas chromatographic–tandem-mass spectrometric procedure. The medians (95th percentiles) of the MTp levels in indoor air were 9.1 μg m^− 3 (94 μg m^− 3) for LMN, 2.6 μg m^− 3 (13 μg m^− 3) for αPN, and < 1.0 μg m^− 3 (3.2 μg m^− 3) for CRN. None of the day care centers exceeded the German health precaution or hazard guide value. In spite of the low MTp air exposure, the urine analyses revealed an exposure to the three monoterpenes in almost all children. The median levels of MTp metabolites in urine were 0.11 mg L^− 1 for LMN-8,9-OH, 0.10 mg L^− 1 for LMN-1,2-OH, 49 μg L^− 1 for PA, 2.9 μg L^− 1 for POH, 5.2 μg L^− 1 for tCAR, and 4.1 μg L^− 1 for cCAR (LMN metabolites), 7.2 μg L^− 1 for MYR, 19 μg L^− 1 for tVER, and 19 μg L^− 1 for cVER (αPN metabolites), as well as 8.2 μg L^− 1 for CRN-10-COOH (CRN metabolite). Statistically significant and strong correlations among the urinary metabolites of each MTp were found. Moreover, statistical associations between LMN metabolites and the LMN indoor air levels were revealed. However, the weakness of the associations indicates a considerable impact of other MTp sources, e.g. diet and consumer products, on the internal exposure.     

Route-specific daily uptake of organochlorine pesticides in food,dust, and air by Shanghai residents,China

Dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexanes (HCHs) are widely detected in the environment, although they have been banned in China since 1980s. To better understand the route-specific daily uptake of the pesticides by humans, a total of 322 food, dust, and air samples were collected in Shanghai, China, during 2008–2011. The median concentrations were 0.2–126.6 and 0.03–1.6 ng/g wet weight for DDTs (DDT and its metabolites) and HCHs, respectively, in different types of foods. The values in dust (indoors and outdoors) were 5.7–29.8 and 1.3–5.4 ng/g, and 13.9 × 10^− 3 and 2.6 × 10^− 3 ng/m³ in air (gas + particle) for DDTs and HCHs, respectively. The daily uptake of a pesticide by humans was calculated via the pesticide intake multiplied by its uptake efficiency. The uptake efficiencies of DDTs and HCHs in food through human intestines were estimated using bioaccessibility measured via an in vitro method simulating the human gastrointestinal digestion process. The total daily uptakes of DDTs and HCHs through three routes (i.e., ingestion, inhalation, and dermal contact) were 79.4 and 4.9 ng/day, respectively, for children, and 131.1 and 8.0 ng/day, respectively, for adults. Ingestion via food and dust was the main route of human exposure to the pesticides, and the daily uptake of the pesticides via food consumption accounted for 95.0–99.2% of the total.     

Radionuclide concentrations in soil and lifetime cancer risk due to gamma radioactivity in Kirklareli,Turkey

The objective of this study is to evaluate and map soil radionuclides' activity concentrations and environmental outdoor gamma dose rates (terrestrial and cosmic) in Kirklareli, Turkey. The excess lifetime cancer risks are also calculated. Outdoor gamma dose rates were determined in 230 sampling stations and soil samples were taken from 177 locations. The coordinates of the readings were determined by the Global Positioning System (GPS). The outdoor gamma dose rates were determined by Eberline smart portable device (ESP-2) and measurements were taken in air for two minutes at 1 m from the ground. The average outdoor gamma dose rate was 118 ± 34 nGy h^?1. Annual effective gamma dose of Kirklareli was 144 μSv and the excess lifetime cancer risk of 5.0 × 10^?4. Soil samples were analyzed by gamma spectroscopy. The average ²²⁶Ra, ²³⁸U, ²³²Th, ¹³⁷Cs, and ⁴⁰K activities were 37 ± 18 Bq kg^?1, 28 ± 13 Bq kg^?1, 40 ± 18 Bq kg^?1, 8 ± 5 Bq kg^?1 and 667 ± 281 Bq kg^?1, respectively. The average soil radionuclides' concentrations of Kirklareli were within the worldwide range although some extreme values had been determined. Annual effective gamma doses and the excess lifetime risks of cancer were higher than the world's average.     

Sources and human exposure implications of concentrations of organophosphate flame retardants in dust from UK cars,classrooms, living rooms,and offices

Concentrations of a number of organophosphate flame retardants (PFRs) were measured in floor dust collected from UK living rooms (n = 32), cars (n = 21), school and child daycare centre classrooms (n = 28), and offices (n = 61). While concentrations were overall broadly within the range of those reported previously for North America, Japan, and other European countries, median concentrations of TCIPP in all UK microenvironments exceeded those reported elsewhere in the world. Moreover, concentrations of TCIPP and TDCIPP in 2 UK car dust samples were – at 370 μg g^− 1 and 740 μg g^− 1 respectively – amongst the highest reported globally in indoor dust to date. Consistent with this, concentrations of TDCIPP in dust from UK cars exceed significantly those detected in the other microenvironments studied. Concentrations of EHDPP were shown for the first time to be significantly higher in classroom dust than in samples from other microenvironments. When compared to concentrations of PBDEs determined previously in the classroom dust samples; concentrations of all target PFRs exceeded substantially those of those PBDEs that are the principal constituents of the Penta- and Octa-BDE formulations. Moreover, while mass-based concentrations of BDE-209 exceeded those of most of our target PFRs, they still fell below those of TCIPP and EHDPP. In line with a previous observation in Sweden that indoor air contamination with TNBP was significantly lower in newer buildings; concentrations of TNBP in classroom dust were significantly higher in older compared to more recently-constructed schools. Consistent with the reported extensive use of TCIPP and TDCIPP in polyurethane foam, the highest concentrations of both TCIPP and TDCIPP in the classrooms studied, were observed in rooms containing the highest numbers of foam chairs (n = 31 and 18 respectively). Exposure to PFRs of both adults and young children via ingestion of indoor dust was estimated. While even our high-end exposure estimate for young children was ~ 100 times lower than one previously reported health-based limit (HBLV) value for TCIPP; the margin of safety was only 5-fold when compared to another HBLV for this contaminant.     

Fibrin clot structure is affected by levels of particulate air pollution exposure in patients with venous thrombosis

BackgroundParticulate air pollution is a risk factor for cardiovascular diseases and thrombosis. Long-term exposure to particulate matter with a diameter < 10 μm (PM₁₀) has been associated with an increased risk of venous thrombosis.ObjectivesThe aim of this study was to investigate whether or not particulate air pollution alters fibrin clot structure and thus modulates thrombosis risk.MethodsWe investigated fibrin polymerization by turbidity (maximum absorbance mOD), clot structure by confocal microscopy (fibre number per μm) and fibrin pore size by permeability (Ks × 10^− 10 cm²) in 103 patients with deep vein thrombosis and 121 healthy controls, for whom levels of air pollution exposure had been recorded. Exposure groups were defined by mean PM₁₀ concentrations over the 730 days before the event.ResultsWe found a higher average number of fibres per clot area in patients than controls, but no difference in Ks or fibre thickness. When the two groups were divided into high or low exposure to PM₁₀, a significantly denser fibrin clot network structure with thicker fibres (higher maximum absorbance, p < 0.05), decreased permeability (lower Ks value, p < 0.05) and higher average fibre numbers per clot area (p < 0.05) was observed in patients in the high exposure group compared to those with low exposure. There were no significant differences in fibrin clot structure between the two exposure levels in healthy subjects.ConclusionsPM₁₀ levels are associated with altered fibrin clot structure in patients with deep vein thrombosis but not in controls, suggesting that air pollution may trigger differences in fibrin clot structure only in patients predisposed to thrombotic disease.     

Concentrations of polybrominated diphenyl ethers (PBDEs) in matched samples of human milk,dust and indoor air

Polybrominated diphenyl ethers (PBDEs) are lipophilic, persistent pollutants found worldwide in environmental and human samples. Exposure pathways for PBDEs remain unclear but may include food, air and dust. The aim of this study was to conduct an integrated assessment of PBDE exposure and human body burden using 10 matched samples of human milk, indoor air and dust collected in 2007–2008 in Brisbane, Australia. In addition, temporal analysis was investigated comparing the results of the current study with PBDE concentrations in human milk collected in 2002–2003 from the same region.PBDEs were detected in all matrices and the median concentrations of BDEs -47 and -209 in human milk, air and dust were: 4.2 and 0.3 ng/g lipid; 25 and 7.8 pg/m³; and 56 and 291 ng/g dust, respectively. Significant correlations were observed between the concentrations of BDE-99 in air and human milk (r = 0.661, p = 0.038) and BDE-153 in dust and BDE-183 in human milk (r = 0.697, p = 0.025). These correlations do not suggest causal relationships — there is no hypothesis that can be offered to explain why BDE-153 in dust and BDE-183 in milk are correlated. The fact that so few correlations were found in the data could be a function of the small sample size, or because additional factors, such as sources of exposure not considered or measured in the study, might be important in explaining exposure to PBDEs. There was a slight decrease in PBDE concentrations from 2002–2003 to 2007–2008 but this may be due to sampling and analytical differences. Overall, average PBDE concentrations from these individual samples were similar to results from pooled human milk collected in Brisbane in 2002–2003 indicating that pooling may be an efficient, cost-effective strategy of assessing PBDE concentrations on a population basis.The results of this study were used to estimate an infant's daily PBDE intake via inhalation, dust ingestion and human milk consumption. Differences in PBDE intake of individual congeners from the different matrices were observed. Specifically, as the level of bromination increased, the contribution of PBDE intake decreased via human milk and increased via dust. As the impacts of the ban of the lower brominated (penta- and octa-BDE) products become evident, an increased use of the higher brominated deca-BDE product may result in dust making a greater contribution to infant exposure than it does currently.To better understand human body burden, further research is required into the sources and exposure pathways of PBDEs and metabolic differences influencing an individual's response to exposure. In addition, temporal trend analysis is necessary with continued monitoring of PBDEs in the human population as well as in the suggested exposure matrices of food, dust and air.     

Brominated and chlorinated flame retardants in San Francisco Bay sediments and wildlife

Restrictions on the use of polybrominated diphenyl ethers (PBDEs) have resulted in the use of alternative flame retardants in consumer products to comply with flammability standards. In contrast to PBDEs, information on the occurrence and fate of these alternative compounds in the environment is limited, particularly in the United States. In this study, a survey of flame retardants in San Francisco Bay was conducted to evaluate whether PBDE replacement chemicals and other current use flame retardants were accumulating in the Bay food web. In addition to PBDEs, brominated and chlorinated flame retardants (hexabromocyclododecane (HBCD) and Dechlorane Plus (DP)) were detected in Bay sediments and wildlife. Median concentrations of PBDEs, HBCD, and DP, respectively, were 4.3, 0.3, and 0.2 ng g^− 1 dry weight (dw) in sediments; 1670, < 6.0, and 0.5 ng g^− 1 lipid weight (lw) in white croaker (Genyonemus lineatus); 1860, 6.5, and 1.3 ng g^− 1 lw in shiner surfperch (Cymatogaster aggregata); 5500, 37.4, and 0.9 ng g^− 1 lw in eggs of double-crested cormorant (Phalacrocorax auritus); 770, 7.1, and 0.9 ng g^− 1 lw in harbor seal (Phoca vitulina) adults; and 330, 3.5, and < 0.1 ng g^− 1 lw in harbor seal (P. vitulina) pups. Two additional flame retardants, pentabromoethylbenzene (PBEB) and 1,2-bis(2,4,6 tribromophenoxy)ethane (BTBPE) were detected in sediments but with less frequency and at lower concentrations (median concentrations of 0.01 and 0.02 ng g^− 1 dw, respectively) compared to the other flame retardants. PBEB was also detected in each of the adult harbor seals and in 83% of the pups (median concentrations 0.2 and 0.07 ng g^− 1 lw, respectively). The flame retardants hexabromobenzene (HBB), decabromodiphenyl ethane (DBDPE), bis(2-ethylhexyl) tetrabromophthalate (TBPH), and 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB), were not detected in sediments and BTBPE, HBB and TBB were not detected in wildlife samples. Elevated concentrations of some flame retardants were likely associated with urbanization and Bay hydrodynamics. Compared to other locations, concentrations of PBDEs in Bay wildlife were comparable or higher, while concentrations of the alternatives were generally lower. This study is the first to determine concentrations of PBDE replacement products and other flame retardants in San Francisco Bay, providing some of the first data on the food web occurrence of these flame retardants in a North American urbanized estuary.