Environmental tobacco smoke and measures of subclinical vascular disease

Indoor air quality in a bar/restaurant before and after the smoking ban in Athens, Greece

In this study we compared indoor air pollutant concentrations in a bar/restaurant in Greece before and after the enactment of a smoking ban legislation of 2008. This was done to investigate whether the separation of the venue into smoking and non-smoking areas will have an impact on workers and customers from secondhand smoke (SHS) exposure (null hypothesis). The study was completed within an 8-month period beginning in March 2010 and ending on November 2010. We compared the average of the measured PM0.1 concentrations in the smoking zones between the pre-ban and post-ban periods. Overall reduction in the number of particles was 18% between pre-ban and post-ban periods. The mean of the 36 total CO2 measurements for the pre- and the post-ban period was 611ppm. We calculated the ventilation rates per occupant (Vo in l/s/occ) and found it to be higher in the post-ban period (19.4l/s/occ), thus complying with the ASHARAE standard for Vo of 15l/s/occ at maximum occupancy, than in the pre-ban period (10.7l/s/occ). The mean of the 36 total CO measurements for the pre-ban period was 2 ppm. CO measurements in the post-ban period were less than the detection limit of 1 ppm. Emissions of nitrogen dioxide and formaldehyde weren't detected in any of the zones. It was observed there was about 50% distribution of pollutants from the smoking zones to the smoke-free zones. The smoking ban effect on the occupancy levels was initially reduced by 16%, but based on other similar studies this transition period will be followed by an increase in the occupancy. Passive smoking and associated risks were significantly reduced but not totally eliminated, indicating the need for stronger enforcement or complete partition between smoking and non-smoking areas.

Endothelial dysfunction: associations with exposure to ambient fine particles in diabetic individuals

BACKGROUND

Exposure to fine airborne particulate matter [< or =2.5 microm in aerodynamic diameter (PM(2.5))] has been associated with cardiovascular and hematologic effects, especially in older people with cardiovascular disease. Some epidemiologic studies suggest that adults with diabetes also may be a particularly susceptible population.

OBJECTIVES

The purpose of this study was to analyze the short-term effects of ambient PM(2.5) on markers of endothelial function in diabetic volunteers.

METHODS

We conducted a prospective panel study in 22 people with type 2 diabetes mellitus in Chapel Hill, North Carolina (USA), from November 2004 to December 2005. We acquired daily measurements of PM(2.5) and meteorologic data at central monitoring sites. On 4 consecutive days, we measured endothelial function by brachial artery ultrasound in all participants and by pulsewave measurements in a subgroup. Data were analyzed using additive mixed models with a random participant effect and adjusted for season, day of the week, and meteorology.

RESULTS

Flow-mediated dilatation decreased in association with PM(2.5) during the first 24 hr, whereas small-artery elasticity index decreased with a delay of 1 and 3 days. These PM(2.5)-associated decrements in endothelial function were greater among participants with a high body mass index, high glycosylated hemoglobin A1c, low adiponectin, or the null polymorphism of glutathione S-transferase M1. However, high levels of myeloperoxidase on the examination day led to strongest effects on endothelial dysfunction.

CONCLUSIONS

These data demonstrate that PM(2.5) exposure may cause immediate endothelial dysfunction. Clinical characteristics associated with insulin resistance were associated with enhanced effects of PM on endothelial function. In addition, participants with greater oxidative potential seem to be more susceptible.

Effects of passive smoking on heart rate variability, heart rate and blood pressure: an observational study

BACKGROUND

Exposure to environmental tobacco smoke (ETS) has been shown to increase the risk for cardiovascular diseases and death, and autonomic dysfunction (specifically, reduced heart rate variability (HRV)) is a predictor of increased cardiac risk. This study tests the hypothesis that ETS exposure reduces HRV in the general population and discusses possible pathways.

METHODS

This cross-sectional study was conducted between 2001 and 2003 and is part of the SAPALDIA (Swiss Cohort Study on Air Pollution and Lung Diseases in Adults) study. The analysis included 1218 randomly selected non-smokers aged 50 and above who participated in 24-h electrocardiogram recordings. Other examinations included an interview, investigating health status (especially respiratory and cardiovascular health and health relevant behaviours and exposure to ETS) and measurements of blood pressure, body height and weight.

RESULTS

Subjects exposed to ETS at home or at work for more than 2 h/day had a difference of -15% in total power (95%CI: -26 to -3%), low frequency power (-28 to -1%), low/high frequency ratio (-26 to -3%) and -18% (-29 to -4%) in ultralow frequency power of HRV compared with subjects not exposed to ETS at home or work. We also found a 2.7% (-0.01 to 5.34%) higher heart rate during the recording in exposed subjects.

CONCLUSIONS

Exposure to ETS at home and work is associated with lower HRV and with higher heart rate in an ageing population. Our findings suggest that exposure to ETS increases cardiac risk through disturbances in the autonomic nervous system.

Environmental tobacco smoke exposure in public places of European cities

BACKGROUND

Exposure to environmental tobacco smoke (ETS) has important public health implications. The results of the first European multi-centre study that measured ETS exposure in a range of public places (transport, educational settings, and leisure facilities such as bars and restaurants) are presented.

METHOD

Nicotine vapour phase was measured using ETS passive samplers containing a filter treated with sodium bisulfate.

RESULTS

Bars and discos are the places with the highest concentrations of nicotine from ETS, median ranging from 19 to 122 microg/m(3). Restaurants had the next highest values. Concentrations of nicotine generally range from 0.1-5 microg/m(3) in airports, and from 0.5-10 microg/m(3) in train stations. Nicotine was also found in schools and universities, yet schools tended to have the lowest concentrations compared to all the other public places sampled. In hospitals levels were generally below 5 microg/m(3).

CONCLUSIONS

Although there is some variability between cities, this study shows that tobacco smoke is present in most of the studied public places. The study also showed that in areas where smoking is prohibited, concentrations of nicotine are lower than in areas where smoking is allowed but they are not zero. The results of this study indicate that policies should be implemented that would effectively reduce levels of tobacco smoke in public areas.

Air Pollution and Cardiovascular Disease

Air pollution is a heterogeneous, complex mixture of gases, liquids, and particulate matter. Epidemiological studies have demonstrated a consistent increased risk for cardiovascular events in relation to both short- and long-term exposure to present-day concentrations of ambient particulate matter. Several plausible mechanistic pathways have been described, including enhanced coagulation/thrombosis, a propensity for arrhythmias, acute arterial vasoconstriction, systemic inflammatory responses, and the chronic promotion of atherosclerosis. The purpose of this statement is to provide healthcare professionals and regulatory agencies with a comprehensive review of the literature on air pollution and cardiovascular disease. In addition, the implications of these findings in relation to public health and regulatory policies are addressed. Practical recommendations for healthcare providers and their patients are outlined. In the final section, suggestions for future research are made to address a number of remaining scientific questions.

Acute exposure to environmental tobacco smoke and heart rate variability

Environmental tobacco smoke (ETS) has been associated with cardiovascular mortality. Pathophysiologic pathways leading from ETS exposure to cardiopulmonary disease are still being explored. Reduced cardiac autonomic function, as measured by heart rate variability (HRV), has been associated with cardiac vulnerability and may represent an important pathophysiologic mechanism linking ETS and risk of cardiac mortality. In this study we evaluated acute ETS exposure in a commercial airport with changes in HRV in 16 adult nonsmokers. We conducted ambulatory electrocardiographic (ECG) monitoring for 8-hr periods while participants alternated 2 hr in nonsmoking and smoking areas. Nicotine and respirable suspended particle concentrations and participants' blood oxygen saturation were also monitored. We calculated time and frequency domain measures of HRV for periods in and out of the smoking area, and we evaluated associations with ETS using comparative statistics and regression modeling. ETS exposure was negatively associated with all measures of HRV. During exposure periods, we observed an average decrement of approximately 12% in the standard deviation of all normal-to-normal heart beat intervals (an estimate of overall HRV). ETS exposures were not associated with mean heart rate or blood oxygen saturation. Altered cardiac autonomic function, assessed by decrements in HRV, is associated with acute exposure to ETS and may be part of the pathophysiologic mechanisms linking ETS exposure and increased cardiac vulnerability.

Summary: workshop on health risks attributable to ETS exposure in the workplace

This 1998 workshop was convened to address the health risks of exposure to environmental tobacco smoke (ETS) in the workplace. It was paired with a 1997 workshop on issues related to ETS exposure in work environments ((italic)1(/italic)). In the 1998 workshop, a multidisciplinary group of participants was charged with reviewing evidence on the quantitative risks to health posed by ETS and to discuss development of risk assessment methodology for the future. The overall charges for the present workshop were to consider various health outcomes and make recommendations regarding those health outcomes to be included in assessment of health risk resulting from ETS in the workplace; to consider available studies addressing these health outcomes and to evaluate the validity of data for estimating risk from occupational ETS exposure; to review and evaluate mathematical models useful for estimating the risk due to ETS exposure; to examine dose-response models and to characterize the models regarding validity and uncertainty in estimating health risk attributable to ETS exposure in the workplace.