Department of Environmental Medicine, Institute of Public Health (C.A.G.T., L.I.R., C.D., P.G., F.N., T.K.J.), and Institute of Sports Science and Clinical Biomechanics (A.G., M.R.-L., L.B.A.), University of Southern Denmark, 5000 Odense C, Denmark; and Department of Biostatistics (K.D.S., T.S.), University of Copenhagen, 1353 Copenhagen, Denmark.
Our objective was to explore whether childhood exposure to perfluorinated and polyfluorinated compounds (PFCs), widely used stain- and grease-repellent chemicals, is associated with adiposity and markers of glycemic control.
Body mass index, skinfold thickness, waist circumference, leptin, adiponectin, insulin, glucose, and triglyceride concentrations were assessed in 8- to 10-year-old children in 1997 in a subset of the European Youth Heart Study, Danish component. Plasma PFC concentrations were available from 499 children. Linear regression models were performed to determine the association between PFC exposure and indicators of adiposity and markers of glycemic control.
There was no association between PFC exposures and adiposity or markers of glycemic control in normal-weight children. Among overweight children, an increase of 10 ng perfluorooctane sulfonic acid/mL plasma was associated with 16.2% (95% confidence interval [CI], 5.2%-28.3%) higher insulin concentration, 12.0% (95% CI, 2.4%-22.4%) higher ß-cell activity, 17.6% (95% CI, 5.8%-30.8%) higher insulin resistance, and 8.6% (95% CI, 1.2%-16.5%) higher triglyceride concentrations, and an increase of 10 ng perfluorooctanoic acid/mL plasma was associated with 71.6% (95% CI, 2.4%-187.5%) higher insulin concentration, 67.5% (95% CI, 5.5%-166.0%) higher ß-cell function, 73.9% (95% CI, 0.2%-202.0%) higher insulin resistance, and 76.2% (95% CI, 22.8%-153.0%) higher triglyceride concentrations.
Increased PFC exposure in overweight 8- to 10-year-old children was associated with higher insulin and triglyceride concentrations. Chance findings may explain some of our results, and due to the cross-sectional design, reverse causation cannot be excluded. The findings therefore need to be confirmed in longitudinal studies.
Time series of daily administrative cardio-respiratory health and environmental information have been extensively used to assess the potential public health impact of ambient air pollution. Both series are subject to strong but unrelated temporal cycles. These cycles must be removed from the time series prior to examining the role air pollution plays in exacerbating cardio-respiratory disease. In this paper, we examine a number of methods of temporal filtering that have been proposed to eliminate such temporal effects. The techniques are illustrated by linking the number of daily admissions to hospital for respiratory diseases in Toronto, Canada for the 11 year period 1981 to 1991 with daily concentrations of ambient ozone. The ozone-hospitalization relationship was found to be highly sensitive to the length of temporal cycle removed from the admission time series, and to day of the week effects, ranging from a relative risk of 0.874 if long wave cycles were not removed at all to 1.020 for models which removed at least cycles greater than or equal to one month based on the interquartile pollutant range. The specific statistical method of adjustment was not a critical factor. The association was not as sensitive to removal of cycles less than one month, except that negative autocorrelation increased for series in which cycles of one week or less were removed. We recommend three criteria in selecting the degree of smoothing in the outcome: removal of temporal cycles, minimizing autocorrelation and optimizing goodness of fit. The association between ambient ozone levels and hospital admissions for respiratory diseases was also sensitive to the season of examination, with weaker associations observed outside the summer months.
This study aims to assess the atmospheric concentrations of methylcyclopentadienyl manganese tricarbonyl (MMT), respirable manganese (MNR) and total manganese (MnT) in certain specific microenvironments and to provide an estimation of human exposure to MnR. Sampling was carried out in five microenvironments: a gas station, an underground car park, downtown Montreal, near an expressway and near an oil refinery. The samples were collected using Gil-Air portable pumps during three days and were analyzed by instrumental neutron activation analysis (INAA). The mean concentrations of MnR, MnT and MMT were 0.036 microgram m-3, 0.103 microgram m-3 and 0.005 microgram m-3 respectively. The MnR/MnT ratios vary from 25% to 43% (mean 35%) while the MMT/MnT ratios averaged about 5%. Furthermore, the mean concentration of the MnR measured near the expressway (0.053 microgram m-3) is similar to the United States Environmental Protection Agency (U.S. EPA) reference concentration (RfC = 0.05 microgram m-3). The average daily environmental exposure dose to MNR is estimated at 0.010 microgram kg-1 d-1 and its contribution to the multimedia exposure (air, food and water) is low. The overall results show a lack of potential exposure to MMT and substantial concentrations of MnR near an expressway.
The Peace Bridge in Buffalo, New York, which spans the Niagara River at the east end of Lake Erie, is one of the busiest U.S. border crossings. The Peace Bridge plaza on the U.S. side is a complex of roads, customs inspection areas, passport control areas, and duty-free shops. On average 5000 heavy-duty diesel trucks and 20,000 passenger cars traverse the border daily, making the plaza area a potential "hot spot" for emissions from mobile sources. In a series of winter and summer field campaigns, we measured air pollutants, including many compounds considered by the U.S. Environmental Protection Agency (EPA*) as mobile-source air toxics (MSATs), at three fixed sampling sites: on the shore of Lake Erie, approximately 500 m upwind (under predominant wind conditions) of the Peace Bridge plaza; immediately downwind of (adjacent to) the plaza; and 500 m farther downwind, into the community of west Buffalo. Pollutants sampled were particulate matter (PM)
In this report, we examine the associations between emergency department (ED) visits for acute ischemic stroke and environmental conditions.
The study concerned 10,881 ED visits for acute ischemic stroke (ICD-9: 434, 436) recorded at Edmonton hospitals between 1992 and 2002. Generalized linear mixed models technique was applied to build the statistical models. The logarithm of daily counts of ED visits for stroke was regressed on the levels of air pollutants (CO, NO2, SO2, and O3) and two meteorological variables. The analyses were performed by (a) age: two age groups were distinguished: 20-64 years (n=2873) and 65-100 years (n=8008); (b) season (all seasons: January-December, warm: April-September, cold: October-March); and (c) gender (both, male, female).
The results are reported as an excess risk in relation to an increase in the interquartile range (IQR) of the pollutants. In the age group 65-100 years, the excess risk for particular pollutants was as follows: for NO2-8.2% (95% CI: 0.4-16.7) for both genders, in the warm season; for SO2-9.1% (95% CI: 2.2-16.4), for males, in the warm season: for a 1-day lagged SO2-6.0% (95% CI: 0.5-11.8), for females, in the cold season. Among the patients aged 20-64 years, the excess risk for NO2 was 6.3% (95% CI: 0.2-12.8), for both genders, and all seasons; and 13.8% (95% CI: 2.1-26.7), for females, in the cold season; for a 1-day lagged O3-17.8% (95% CI: 2.2-35.6), for males, in the warm season; for a 1-day lagged SO2-10.3% (95% CI: 0.7-20.9) for females, in the cold season.
The findings provide evidence that exposure to air pollutants is significantly associated with ED visits for acute ischemic stroke.
Days of high ambient carbon dioxide (CO) have been associated with increased hospital admissions for cardiac disease. This study was conducted to determine if daily concentrations of CO and fine particulates (PM2.5) are associated with daily changes in heart rate variability.
Each of 36 adults with coronary artery disease had personal exposure to PM2.5 and CO measured along with heart rate variability for one 24-hour period each week for up to 10 weeks.
Among those not taking beta-receptor blockers, there was a positive association between the standard deviation of the R-to-R intervals and CO (P = 0.02). No effect was found for PM2.5.
Urban exposure to CO may exert a biologic effect on the heart, which may be modified by medications.
An investigation of ambient levels and sources of volatile organic compounds (VOCs) and associated public health risks was carried out at two northern Alberta oil sands communities (Fort McKay and Fort McMurray located?30?km from oil sands development, respectively) for the period January 2010-March 2015. Levels of total detected VOCs were comparatively similar at both communities (Fort McKay: geometric mean?=?22.8?µg/m3, interquartile range, IQR?=?13.8-41?µg/m3); (Fort McMurray: geometric mean?=?23.3?µg/m3, IQR?=?12.0-41?µg/m3). In general, methanol (24%-50%), alkanes (26%-32%) and acetaldehyde (23%-30%) were the predominant VOCs followed by acetone (20%-24%) and aromatics (~9%). Mean and maximum ambient concentrations of selected hazardous VOCs were compared to health risk screening criteria used by United States regulatory agencies. The Positive matrix factorization (PMF) model was used to identify and apportion VOC sources at Fort McKay and Fort McMurray. Five sources were identified at Fort McKay, where four sources (oil sands fugitives, liquid/unburned fuel, ethylbenzene/xylene-rich and petroleum processing) were oil sands related emissions and contributed to 70% of total VOCs. At Fort McMurray six sources were identified, where local sources other than oil sands development were also observed. Contribution of aged air mass/regional transport including biomass burning emissions was ~30% of total VOCs at both communities. Source-specific carcinogenic and non-carcinogenic risk values were also calculated and were below acceptable and safe levels of risk, except for aged air mass/regional transport (at both communities), and ethylbenzene/xylene-rich (only at Fort McMurray).
Super slim cigarettes are a relatively new type of cigarette in Canada, and an analysis of select toxicants in the mainstream smoke emissions of the super slim cigarette was conducted.
The yields of selected toxicants in the mainstream smoke emissions of six brands of super slim cigarettes were compared with the Canadian Benchmark, which represents the cigarette designs most commonly found in Canada. A super slim cigarette was also compared with a 'Reference Cigarette' to study the impact of the significantly reduced circumference on mainstream smoke emissions.
Compared with the Canadian Benchmark, the yields of carbon monoxide, the carbonyls, volatiles and the aromatic amines were significantly lower for the super slim cigarette, but the yields of formaldehyde and ammonia were significantly higher. For brands containing a mixed tobacco blend, the yields of tobacco-specific nitrosamines were increased significantly. The reduced circumference of the super slim cigarette resulted in a lower tobacco weight, which together with filter ventilation resulted in lower yields of many toxicants. However, the reduced circumference increased significantly the yields of formaldehyde and phenols in mainstream smoke emissions.
The notably slimmer design of the super slim cigarette resulted in lower yields of some toxicants in the mainstream smoke emissions. However, there were also significant increases in some toxicant levels in the mainstream smoke emissions including formaldehyde, ammonia and the phenols. There are no changes in emission levels that have been shown to reduce exposure or risk in a way that is meaningful, and therefore, the super slim cigarette should not be considered a 'less harmful' cigarette.
Optically stimulated luminescence (OSL) has been used for estimation of the accumulated doses in quartz inclusions obtained from two fired bricks, extracted in July 2004 from a building located in the forested surroundings of the recreational area Novie Bobovichi, the Bryansk Region, Russia. The area was significantly contaminated by Chernobyl fallout with initial (137)Cs ground deposition level of approximately 1.1 MBq m(-2). The accumulated OSL doses in sections of the bricks varied from 141 to 207 mGy, of which between 76 and 146 mGy are attributable to Chernobyl fallout. Using the OSL depth-dose profiles obtained from the exposed bricks and the results from a gamma-ray-survey of the area, the Chernobyl-related cumulative gamma-ray dose for a point detector located in free air at a height of 1m above the ground in the study area was estimated to be ca. 240 mGy for the time period starting on 27 April 1986 and ending on 31 July 2004. This result is in good agreement with the result of deterministic modelling of the cumulative gamma-ray dose in free air above undisturbed ground from the Chernobyl source in the Bryansk Region. Over the same time period, the external Chernobyl-related dose via forest pathway for the most exposed individuals (e.g., forest workers) is estimated to be approximately 39 mSv. Prognosis for the external exposure from 1986 to 2056 is presented and compared with the predictions given by other investigators of the region.