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Secondhand smoke and indoor public spaces in Paducah, Kentucky.

INTRODUCTION: Secondhand smoke (SHS) is the third leading cause of preventable death in the United States. It is responsible for an estimated 3,000 lung cancer deaths annually in never-smokers in the US. It also accounts for over 35,000 deaths annually from coronary heart disease in never-smokers. It increases the number and severity of asthmatic attacks in over 300,000 asthmatic children each year, and is associated with Sudden Infant Death Syndrome and middle ear infections, in addition to other illnesses in children. The purpose of this study was to examine indoor air quality in a sample of hospitality venues in Paducah, Kentucky. The relation between indoor air pollution and the presence of on premises smoking was assessed. METHODS: A Personal Aerosol Monitor was used to sample and record the levels of respirable suspended particles in the air. The SidePak uses a built-in sampling pump that draws air through the device and the particulate matter in the air scatters the light from a laser. Based on this light scattering, the device determines to assess the real-time concentration of particles smaller than 2.5 microm in micrograms per cubic meter, or PM2.5. RESULTS: The average PM2.5 concentration in the eleven locations sampled in Paducah, Kentucky, was 177 microg/m3. The average fine particle pollution level in the non-smoking sections tested was 87 microg/m3, which is 29 times higher than the average fine particle pollution level in smoke-free air or 6 times higher than outdoor air in Paducah. The average PM2.5 level across all nine smoking-permitted hospitality locations sampled in Paducah was 200 microg/m3. For a full-time employee in the venues sampled in this study, the average annual PM2.5 exposure would be 46 microg/m3 (assuming exposure to 200 microg/m3 on the job, exposure to zero particles off the job, and a 40-hour work week). The EPA average annual PM2.5 limit is exceeded by 3.1 times due solely to occupational exposure. Of the ten locations visited that permit indoor smoking, the air monitoring was done in the non-smoking section of six of them. These locations included five restaurants and one public government office. The average fine particle pollution level in these non-smoking sections was 87 microg/m3, which is 29 times higher than the average fine particle pollution level in smoke-free air or 6 times higher than outdoor air in Paducah. It is also interesting to note that the average fine particle pollution level in the smoking section of one restaurant was actually less than the average fine particle pollution level in the "no smoking" section of two other restaurants. CONCLUSIONS: The effects of secondhand smoke are substantial and rapid, explaining the relatively large health risks associated with secondhand smoke exposure that have been reported in epidemiological studies. This study shows that physically separating smokers and non-smokers is not an effective way to protect non-smoking patrons from tobacco smoke pollution. "No smoking" sections provided protection to nonsmokers that can be characterized as trivial at best. In fact, patrons in Paducah cannot be certain that their exposure will not be higher in the "no smoking" sections of certain venues when compared to the smoking sections of other venues. It is imperative that physicians and other healthcare providers actively and aggressively lobby local policymakers to pass regulatory and/or public health ordinances, which have been demonstrated to be effective in controlling exposure to secondhand smoke.

Air Pollutants↗

Algal-bacterial processes for the treatment of hazardous contaminants: a review.

Microalgae enhance the removal of nutrients, organic contaminants, heavy metals, and pathogens from domestic wastewater and furnish an interesting raw material for the production of high-value chemicals (algae metabolites) or biogas. Photosynthetic oxygen production also reduces the need for external aeration, which is especially advantageous for the treatment of hazardous pollutants that must be biodegraded aerobically but might volatilize during mechanical aeration. Recent studies have therefore shown that when proper methods for algal selection and cultivation are used, it is possible to use microalgae to produce the O(2) required by acclimatized bacteria to biodegrade hazardous pollutants such as polycyclic aromatic hydrocarbons, phenolics, and organic solvents. Well-mixed photobioreactors with algal biomass recirculation are recommended to protect the microalgae from effluent toxicity and optimize light utilization efficiency. The optimum biomass concentration to maintain in the system depends mainly on the light intensity and the reactor configuration: At low light intensity, the biomass concentration should be optimized to avoid mutual shading and dark respiration whereas at high light intensity, a high biomass concentration can be useful to protect microalgae from light inhibition and optimize the light/dark cycle frequency. Photobioreactors can be designed as open (stabilization ponds or high rate algal ponds) or enclosed (tubular, flat plate) systems. The latter are generally costly to construct and operate but more efficient than open systems. The best configuration to select will depend on factors such as process safety, land cost, and biomass use. Biomass harvest remains a limitation but recent progresses have been made in the selection of flocculating strains, the application of bioflocculants, or the use of immobilized biomass systems.

Bacteria↗

Using environmental and growth characteristics of plants to detect long-term changes in response to atmospheric pollution: some examples from British beechwoods.

This study uses the Ellenberg system of plant indicator values, along with Grime et al.'s plant growth strategy values, to investigate the nature of temporal changes in the composition of ground flora in two beechwoods in the Cotswolds region of the UK, currently receiving atmospheric inputs of nitrogen in excess of critical loads. The woods, first surveyed in the early 1960s, were resurveyed in 1998 using the original sampling protocol. Temporal changes in the abundance of individual species at Blackstable West Wood indicate changes in light over time, although decreases in sun species, and both increases and decreases in shade species suggest that this change has been patchy. Analysis of changes in plant community as represented by weighted and unweighted quadrat Ellenberg and CSR scores have yielded more significant results. Blackstable West Wood shows increases in nitrophilic, moist-soil and competitive species accompanied by a decline in stress-tolerant species. In Buckholt Top Wood there has been an increase in sun and moist-soil species, a decrease in competitive species and, when weighted Ellenberg scores are considered, an increase in acid-tolerant species. These changes indicate both the impact of woodland management by selective felling and an underlying influence of enhanced atmospheric deposition especially of nitrogen pollutants. It is concluded that quadrat mean scores are a useful tool especially where few individual species have undergone large temporal changes in abundance. However, lack of correlations between quadrat Ellenberg scores for pH and light on one hand, and their equivalents measured in the field, i.e. soil pH and surrogates for light, such as distance to the nearest tree and tree density, suggest that this approach may not be sensitive enough to pick up small-scale, within site variations. Although harder to interpret, plant strategy scores were found to be a useful additional descriptor, encapsulating a plant's response to a range of environmental factors.

Air Pollutants↗

Ozone precursor monitor for investigating air pollution.

Ozone is designated by the Environmental Protection Agency as one of six principal air pollutants. Of the six, ozone alone is classified as a secondary pollutant since it is not emitted by a specific source. Ozone is formed in the lower atmosphere by photochemical reactions involving the precursors of ozone: gaseous organic compounds (mostly hydrocarbons), nitric oxide, and nitrogen dioxide. This paper describes a new automated method for quantifying the precursors of ozone. An ozone analyzer is coupled to a reaction vessel contained in an irradiation chamber. At timed intervals discrete samples of outside air are drawn into the reaction vessel and irradiated with ultraviolet light. The amount of ozone produced is a measure of the photochemical reactivity potential of the precursor blend. The ozone precursor monitor (OPM) is designed for urban air sampling stations where analyzers for the principal air pollutants are routinely operated. The monitor, however, has other uses. Among special applications of the method that are discussed are its use as an early warning device for forecasting elevated ozone concentrations, a screening system for assessing the photoreactivity of solvents, and a procedure for investigating the transport of ozone precursors from urban to rural areas.

Air Pollutants↗

Experimental studies on human health effects of air pollutants. IV. Short-term physiological and clinical effects of nitrogen dioxide exposure.

Adult male volunteers were exposed to nitrogen dioxide (NO2) at 1.0 ppm in purified air under conditions simulating ambient photochemical smog exposures (2-hr exposure with intermittent light exercise at 31 degrees C and 35% relative humidity). Sham exposures to purified air alone served as controls. Exposure effects were assessed by pulmonary physiological tests and by a standardized clinical evaluation. No statistically physiological changes attributable to NO2 exposure were found except for a marginal loss in forced vital capacity after exposure on two successive days (1.5% mean decrease, P less than .05). Reported respiratory and other symptoms were slightly increased with exposure as compared to control, but the change was not significant. Short-term toxicity of NO2 at peak ambient concentrations appears to be substantially less than that of ozone in healthy people, but adverse NO2 effects in diseased people or in long-term exposures cannot be ruled out at present.

Adult↗

Efficient degradation of toxic organic pollutants with Ni2O3/TiO(2-x)Bx under visible irradiation.

To promote efficient use of solar energy, many studies have focused on the modification of TiO2 to extend its spectral response to visible region. Here we report a combined modification of TiO2 by two components: the nonmetal element boron and the metal oxide Ni2O3. The photocatalyst presents high photocatalytic activity in the visible region, which can efficiently degrade and mineralize toxic organic pollutants such as trichlorophenol (TCP), 2,4-dichlorophenol (2,4-DCP), and sodium benzoate. The dechlorination and mineralization results indicate the photocatalytic pathway via visible light excitation. The study demonstrates that the modification of TiO2 both to extend its spectral response to the visible region and to improve its catalytic efficiency can be achieved by doping with boron, a nonmetal, and Ni2O3, a metal oxide.

Journal Article↗

Dr. Walter C. McCrone's contribution to the characterization and identification of explosives.

Dr. McCrone was an amazing individual, possessing many talents and having many interests. He especially loved applying polarized light microscopy (PLM) to answering the question-at-hand and solving problems. He applied PLM to many different fields including the identification of air pollution particles, asbestos identification, art conservation, pharmaceuticals, industry problems and forensic sciences. A field that I believe he enjoyed the most was the characterization and identification of explosives. Throughout his life he worked on, gave presentations and published articles on the characterization and identification of explosives. Also, he encouraged other scientists to give presentations and publish on the subject by providing "behind the scene" advice and/or be a co-author on a paper. He unselfishly taught others how to apply PLM and incorporate this invaluable tool into their analytical scheme.

Explosions↗

[Chronic bronchitis. Development, prevention].

The adoption of an arbitrary epidemiological definition for chronic bronchitis has enabled some progress to be made in the understanding of the frequency and natural course of this disease. It is important to distinguish between chronic airflow obstruction and chronic hypersecretion of bronchial mucus. The prevalence of the disease can only be assessed in selective groups of the population and varies according to the characteristics of these groups, but is approximately 15% of men and 8% of women. There is relatively low mortality in France: 6/100,000 in 1985 and varies according to the departments, up to 38/100,000 inhabitants. These data ought to be interpreted with care and it is also important to take account of factors linked to their evolution. Longitudinal studies undertaken 20 years ago have allowed two hypotheses to be formulated to aid in a more precise understanding of the natural history of the disease: the first of these was the Dutch hypothesis which is currently undergoing a renewal of interest linked to epidemiological studies on HRB, and the English hypothesis which has the merit of emphasizing the principal risk factor in chronic bronchitis. Certain smokers are sensitive to tobacco, even though some others are not. Does the explanation of this lie in the relationship between obstructive ventilatory problems and bronchial hyper-reactivity? This association is discussed in the light of recent work as well as the relationship between bronchial hyperactivity, smoking and chronic bronchitis. Other risk factors have been studied: occupational hazards, air pollution and acute respiratory infections in childhood. But, in spite of all the work carried out to better define the risk factors and prognosis of the disease, this makes up a complex overall picture which is poorly understood and which should stimulate us to further research. The prevention of the disorder should be aimed at three levels; at the primary level (to prevent the appearance of the disorder) the only objective which may lead to a satisfactory solution in public health terms, a secondary level would be to identify those people or groups at special risk, but it is not recommended to undertake systematic examination of large populations in view of the fact that the early diagnosis of non-specific chronic pulmonary disease as well as special studies have not been shown to demonstrate the value of these procedures. The objective of prevention is to eliminate or neutralise factors linked to the disease.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

Air pollution epidemiologic studies in South Africa--need for freshening up.

The results of epidemiologic studies obtained in developed countries cannot be extrapolated with complete confidence to developing countries. The objectives of this review were to examine the evidence from local studies for associations between air pollution and adverse health along with a critical review for methodologic limitations. The literature search strategy and selection criteria involved a MEDLINE search up to June 2005. Of 267 journal articles found, 14 focused on air pollution epidemiology (excluding active smoking and internal dose as a proxy for health outcomes). Two studies were also located by word of mouth or through the references from the selected studies. The local studies provide some evidence of an association with a range of serious and common health problems. No study established an exposure-response curve for the criteria pollutants carbon monoxide, sulfur dioxide, nitrogen oxides, lead, and ozone. Therefore, using the results of such studies in risk-assessment is impossible. The studies were fraught with systematic and random errors, which limit their validity and precision. We recommend conducting a quantitative intervention study with an analytical study design in all major cities in the countries where residents are still using dirty fuels for cooking, lighting, and space heating. Future studies must involve national and international multidisciplinary stakeholders and must be planned well in advance.

Air Pollutants↗

Regenerative response and endocrine disrupters in crinoid echinoderms: an old experimental model, a new ecotoxicological test.

The regenerative phenomena that reproduce developmental processes in adult organisms and are regulated by endocrine and neurohumoral mechanisms can provide new sensitive tests for monitoring the effects of exposure to anthropogenic chemicals such as endocrine disrupter (ED) contaminants. These pollutants in fact can be bioaccumulated by the organisms, causing dysfunctions in steroid hormone production/metabolism and activities and inducing dramatic effects on reproductive competence, development and growth in many animals, man included. Current research is exploring the effects of exposure to different classes of compounds well known for their ED activity, such as polychlorinated biphenyls (PCBs), nonylphenols and organotins, on regenerative potential of echinoderms, a relatively unexplored and promising applied approach which offers the unique chance to study physiological developmental processes in adult animals. The selected test species is the crinoid Antedon mediterranea, which represents a valuable experimental model for investigation into the regenerative process from the macroscopic to the molecular level. The present study employs an integrated approach which combines exposure experiments, chemical analysis and biological analysis utilizing classical methods of light (LM) and electron (TEM and SEM) microscopy and immunocytochemistry. The experiments were carried out on experimentally induced arm regenerations in controlled conditions with exposure concentrations comparable to those of moderately polluted coastal zones in order to reproduce common conditions of exposure to environmental contaminants. The results of the exposure tests were analysed in terms of effects at the whole organism, at the tissue and cellular level, and possible sites of action of EDs. Our results show that prolonged exposure to these compounds significantly affects the regenerative mechanisms by inducing appreciable anomalies in terms of regeneration times, overall growth, general morphology and histological and cellular pattern. A concentration/effect relationship could be found for all substances. Interestingly, contrasting results in terms of inhibition or acceleration of regeneration phenomenon were obtained for different chemicals.

Animals↗

Photosynthesis in sediments determined at high spatial resolution by the use of microelectrodes.

The present study investigated photosynthetic rates and their regulation by light within the upper 5mm of sediment in a tidal area of Niida River in Hachinohe, Japan. Steady-state concentration profiles of O(2), NH(4)(+), NO(2)(-), H(2)S, and pH in the sediment were measured with microelectrodes. Microzonation of O(2) respiration, denitrification and SO(4)(2-) reduction was found in the sediment. When light intensities exceeded 1050 micromol photons/m(2)/s, net photosynthetic activity was detected in the upper 0.5mm of the microbial mat colonizing on the sediment surface in the tidal area. In contrast, gross photosynthetic activity was detected in the upper 1.0mm of the microbial mat at 1900 micromol photons/m(2)/s. As light intensity increased, the net photosynthetic rate and O(2) penetration depth increased. The maximal net photosynthetic rate and O(2) penetration depth were 6.1 micromol O(2)/cm(3)/h and 2.2mm, respectively, at 1900 micromol photons/m(2)/s. Net photosynthetic rates in the microbial mat in the tidal area were lower than in the upstream sediment. The analysis of continuous O(2) concentration measurements in different layers of the microbial mat during artificial light-dark cycles demonstrated that the photosynthetic activity response to changes in light intensity was extremely fast (a few seconds) and the O(2) concentration in the microbial mat became stable within 200s. The measurement of physical and chemical parameters in river water revealed that the study site was relatively polluted and sunlight intensity significantly fluctuated temporally. These results suggested that the in situ microbial processes occurring in the sediment fluctuated in accordance with periodic fluctuations in sunlight intensity.

Bacteria↗

[Evaluation of atmospheric pollution in industrial environment using gas-chromatographic technics].

Several analytical techniques for the evaluation of different classes of air pollutants that can be found in working places are described. Particularly an automatic apparatus for monitoring total organic substances less methane, and one, employing specific detection and selective columns for the automatic and continuous determination of light sulfur compounds, are described. An analytical procedure for trapping and selective analysis of organic substances is presented. This includes the description of trapping and enriching devices and of a semi-automatic apparatus for the gaschromatographic analysis of the samples trapped. Some applications of these analytical techniques are described.

Air Pollutants↗

California black oak response to nitrogen amendment at a high O3, nitrogen-saturated site.

In a nitrogen (N) saturated forest downwind from Los Angeles, California, the cumulative response to long-term background-N and N-amendment on black oak (Quercus kelloggii) was described in a below-average and average precipitation year. Monthly measurements of leaf and branch growth, gas exchange, and canopy health attributes were conducted. The effects of both pollutant exposure and drought stress were complex due to whole tree and leaf level responses, and shade versus full sun leaf responses. N-amended trees had lower late summer carbon (C) gain and greater foliar chlorosis in the drought year. Leaf water use efficiency was lower in N-amended trees in midsummer of the average precipitation year, and there was evidence of poor stomatal control in full sun. In shade, N-amendment enhanced stomatal control. Small differences in instantaneous C uptake in full sun, lower foliar respiration, and greater C gain in low light contributed to the greater aboveground growth observed.

Acclimatization↗

Optical remote sensing for air pollutants--review.

Air monitoring techniques need to be simple, unobtrusive, acquire real-time data, have increased sensitivity, and the ability to analyze many compounds simultaneously. Optical remote sensing techniques address many of these criteria for air monitoring methods. Optical remote sensing uses light energy between ultraviolet and midinfrared to detect and measure contaminants in situ. While optical remote monitoring techniques provide similar monitoring accuracy compared to conventional monitoring methods, they also provide certain unique advantages. Advantages and disadvantages of specific optical remote sensing techniques is discussed in this review, which focuses on the techniques most useful to the industrial hygiene profession. Detailed information about every technique will not be supplied; rather the review attempts to provide an understanding of the development of the remote sensing techniques, and briefly explains typical applications, so that readers can understand and evaluate applications appropriate to their work.

Air Pollutants↗

Plasmids for heavy metal resistance in Alcaligenes eutrophus CH34: mechanisms and applications.

Alcaligenes eutrophus CH34 is the main representative of a group of strongly related strains (mostly facultative chemolithotrophs) that are well adapted to environments containing high levels of heavy metals. It harbors the megaplasmids pMOL28 and pMOL30 which carry resistance determinants to Co2+, Ni2+, CrO(4)2-, Hg2+, Tl+, Cd2+, Cu2+ and Zn2+. Among the best characterized determinants are the cnr operon (resistance to Co, Ni) on pMOL28 and the czc operon on pMOL30 (resistance to Co, Cd and Zn). Although the two systems reveal a significant degree of amino acid similarity in the structural genes, the regulation of the operons is different. The resistance mechanism in both cases is based on efflux. The efflux mechanism leads to a pH increase outside of the cytoplasmic membrane. Metals are sequestered from the external medium through the bioprecipitation of metal carbonates formed in the saturated zone around the cell. This latter phenomenon can be exploited in bioreactors designed to remove metals from effluents. The bacteria are immobilized on composite membranes in a continuous tubular membrane reactor (CTMR). The effluent continuously circulates through the intertubular space, while the external surface of the tubes is in contact with the growth medium. Metal crystals are eventually removed by the effluent stream and collected on a glass bead column. The system has been applied to effluents containing Cd, Zn, Co, Ni and Cu. By introducing catabolic plasmids involved in the aerobic degradation of PCBs and 2,4-D into metal-resistant A. eutrophus strains, the application range was widened to include effluents polluted with both organic and inorganic substances. Biosensors have been developed which are based on the fusion of genes induced by metals to a reporter system, the lux operon of Vibrio fischeri. Bacterial luciferases produce light through the oxidation of fatty aldehydes. The gene fusions are useful both for the study of regulatory genes and for the determination of heavy metal concentrations in the environment.

Alcaligenes↗

Visible light Cr(VI) reduction and organic chemical oxidation by TiO2 photocatalysis.

Here we report the simultaneous Cr(VI) reduction and 4-chlorophenol (4-CP) oxidation in water under visible light (wavelength > 400 nm) using commercial Degussa P25 TiO2. This remarkable observation was attributed to a synergistic effect among TiO2, Cr(VI), and 4-CP. It is well known that TiO2 alone cannot remove either 4-CP or Cr(VI) efficiently under visible light. Moreover, the interaction between Cr(VI) and 4-CP is minimal if not negligible. However, we found that the combination of TiO2, Cr(VI), and 4-CP together can enable efficient Cr(VI) reduction and 4-CP oxidation under visible light. The specific roles of the three ingredients in the synergistic system were studied parametrically. It was found that optimal concentrations of Cr(VI) and TiO2 exist for the Cr(VI) reduction and 4-CP oxidation. Cr(VI) was compared experimentally with other metals such as Cu(ll), Fe(lll), Mn(IV), Ce(IV), and V(V). Among all these metal ions, only Cr(VI) promotes the photocatalytic oxidation of 4-CP. The amount of 4-CP removed was directly related to the initial concentration of Cr(VI). The system was also tested with four other chemicals (aniline, salicylic acid, formic acid, and diethyl phosphoramidate). We found that the same phenomenon occurred for organics containing acid and/or phenolic groups. Cr(VI) was reduced at the same time as the organic chemicals being oxidized during photoreaction under visible light. The synergistic effect was also found with pure anatase TiO2 and rutile TiO2. This study demonstrates a possible economical way for environmental cleanup under visible light.

Carcinogens, Environmental↗