Carbon monoxide, tobacco smoking, and the pathogenesis of atherosclerosis

Biomarkers of oxidative damage in cigarette smokers: which biomarkers might reflect acute versus chronic oxidative stress?

Cigarette smoking predisposes to the development of multiple diseases involving oxidative damage. We measured a range of oxidative damage biomarkers to understand which differ between smokers and nonsmokers and if the levels of these biomarkers change further during the act of smoking itself. Despite overnight abstinence from smoking, smokers had higher levels of plasma total and esterified F(2)-isoprostanes, hydroxyeicosatetraenoic acid products (HETEs), F(4)-neuroprostanes, 7-ketocholesterol, and 24- and 27-hydroxycholesterol. Levels of urinary F(2)-isoprostanes, HETEs, and 8-hydroxy-2'-deoxyguanosine were also increased compared with age-matched nonsmokers. Several biomarkers (plasma free F(2)-isoprostanes, allantoin, and 7β-hydroxycholesterol and urinary F(2)-isoprostane metabolites) were not elevated. The smokers were then asked to smoke a cigarette; this acute smoking elevated plasma and urinary F(2)-isoprostanes, plasma allantoin, and certain cholesterol oxidation products compared to presmoking levels, but not plasma HETEs or urinary 8-hydroxy-2'-deoxyguanosine. Smokers showed differences in plasma fatty acid composition. Our findings confirm that certain oxidative damage biomarkers are elevated in smokers even after a period of abstinence from smoking, whereas these plus some others are elevated after acute smoking. Thus, different biomarkers do not measure identical aspects of oxidative stress.

The effects of air pollution on the lipid balance of traffic police personnel

BACKGROUND

The purpose of our study was to evaluate the effects of urban pollution on the lipid balance of members of a municipal police force in a big city.

SUBJECTS AND METHODS

Our case-control study comprised 118 male members of the police force performing traffic duties, and 118 blood donors who perform office work, and was paired by age and length of service. Total cholesterol, HDL and triglycerides were studied.

RESULTS

The comparison of the average values of HDL cholesterol and triglycerides between the exposed traffic police group and the control group showed significant differences. The difference in the frequency distributions of HDL cholesterol and triglycerides between the exposed group and control group was significant as well. The results suggest the possibility of an alteration in the lipid balance among asymptomatic people who are exposed to air pollution.

CONCLUSION

The results suggest that some chemical agents (such as carbon dioxide) contained in the urban pollution of a big city could cause dyslipidemia among people exposed to such air pollution.

Monitoring and analysis of occupational exposure to chain saw exhausts

The extent of inhalation exposure to loggers from two-stroke chain saws was measured and evaluated under various conditions. Carbon monoxide, measured by personal air monitoring and determination of carboxyhemoglobin levels of the loggers, was used as an indicator of exhaust exposure. Video recordings were made to analyze the influence of varying working conditions and the individual handling of the chain saw on the amount of pollutants inhaled. The American Conference of Governmental Industrial Hygienists biological exposure index (BEI) for carboxyhemoglobin (3.5%) was exceeded during logging in heavy timber stands. When workers were paid on a piecework basis, carboxyhemoglobinemia increased to its maximum level in the first 2-3 hours of the shift and then declined. After 8 hours carboxyhemoglobin levels were 20-30% lower compared with the maximum. Increased exhaust inhalation with short-term exposures to carbon monoxide up to 400 ppm was observed in the following conditions: (1) felling operations, (2) other operations performed in a leaning of squatting position, (3) limbing in thick tops of coniferous trees, (4) working at low wind velocity, and (5) working in thick forest stands. Maximum allowable blood concentrations for carboxyhemoglobin are exceeded in chain saw operators in logging operations. Blood sampling at the end of the workday is not always suitable for determining the highest carboxyhemoglobin levels in loggers during the shift. The exposure of chain saw operators to exhaust increases under certain conditions.

On the health effects of environmental tobacco smoke

Possible adverse health effects of breathing environmental tobacco smoke include lung cancer, respiratory illnesses in young children, decreased pulmonary function, decreased lung growth, allergy to tobacco, and exacerbation of angina. These effects are reviewed to aid informed discussion on this health issue. Some of the constituents of tobacco smoke are found in the home, the outdoor environment, and the workplace in permissible concentrations and are considered unlikely to cause ill health. A double standard, one in the workplace and another for the public, may be evolving for acceptable health risks.