Workplace exposure to passive smoking and risk of cardiovascular disease: summary of epidemiologic studies.
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We reviewed the published epidemiologic studies addressing the relationship between workplace exposure to environmental tobacco smoke (ETS) and cardiovascular disease risk in three case-control studies and three cohort studies. Although the point estimates of risk for cardiovascular disease exceeded 1.0 in five of six studies, none of the relative risks was statistically significant because of the small number of cardiovascular end points occurring in individual studies. In common with most epidemiologic investigations of the health risks of ETS, none of the workplace studies included independent biochemical validation of ETS exposure. In contrast to the evidence on increased cardiovascular disease risk from exposure to spousal ETS, studies of ETS exposure in the workplace are still sparse and inconclusive. Conversely, there is no biologically plausible reason to believe that the hazards of ETS exposure that have been demonstrated in the home should not also apply to the workplace. (+info)
Size distribution of bacterial and fungal bioaerosols in indoor air.
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The aim of this study was to determine the size distribution of bacteria and fungi occurring in the air of human dwellings. The concentration and size distribution of particulate aerosol, Gram-positive mesophilic bacteria, Gram-negative mesophilic bacteria and fungi were examined in 60 flats situated in the Upper Silesia conurbation, southern Poland. The investigated flats comprised three quantitatively equal (20 flats each) groups: flats without additional emission sources of particulate aerosol and microorganisms (Group I), flats with persons who smoke at least one packet of cigarettes per day (Group II), and flats located near steelworks (Group III). The concentrations of four fractions of particulate aerosol were measured by Harvard impactors (PM 2.5 and PM 10) as well as by cyclone HD and 37 mm filter disc holder (PM 5 and TSP). The concentrations of bacteria and fungi were measured by a particle-sizing six-stage Graseby-Andersen impactor. It was found that the concentrations of particulate aerosol in examined flats were below 0.6 mg/m.(3) and the concentrations of microorganisms were below the level of 10(4) cfu/m.(3). The dominant bacteria present in the air of examined dwellings (Micrococcus/Kocuria spp., Staphylococcus spp., Bacillus spp., Pseudomonadaceae, Aeromonas spp., Nocardia spp.) occurred mostly as single particles in the dwellings without additional emission sources, while in the air of dwellings inhabited by tobacco smokers, they often formed aggregates composed of bacterial and dust particles. The fungi dominant in the air of examined dwellings (Penicillium spp., Aspergillus spp., yeasts) occurred mostly as single particles. (+info)
Characterization of indoor particle sources: A study conducted in the metropolitan Boston area.
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An intensive particle monitoring study was conducted in homes in the Boston, Massachusetts, area during the winter and summer of 1996 in an effort to characterize sources of indoor particles. As part of this study, continuous particle size and mass concentration data were collected in four single-family homes, with each home monitored for one or two 6-day periods. Additionally, housing activity and air exchange rate data were collected. Cooking, cleaning, and the movement of people were identified as the most important indoor particle sources in these homes. These sources contributed significantly both to indoor concentrations (indoor-outdoor ratios varied between 2 and 33) and to altered indoor particle size distributions. Cooking, including broiling/baking, toasting, and barbecuing contributed primarily to particulate matter with physical diameters between 0.02 and 0.5 microm [PM((0.02-0.5))], with volume median diameters of between 0.13 and 0.25 microm. Sources of particulate matter with aerodynamic diameters between 0.7 and 10 microm [PM((0.7-10))] included sauteing, cleaning (vacuuming, dusting, and sweeping), and movement of people, with volume median diameters of between 3 and 4.3 microm. Frying was associated with particles from both PM((0.02-0.5)) and PM((0.7-10)). Air exchange rates ranged between 0.12 and 24.3 exchanges/hr and had significant impact on indoor particle levels and size distributions. Low air exchange rates (< 1 exchange/hr) resulted in longer air residence times and more time for particle concentrations from indoor sources to increase. When air exchange rates were higher (> 1 exchange/hr), the impact of indoor sources was less pronounced, as indoor particle concentrations tracked outdoor levels more closely. (+info)
The relationship between moisture or mould observations in houses and the state of health of their occupants.
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This work was conducted in order to study how the health of adults is affected by the presence of moisture or mould in the home. A random sample of 310 houses in Finland was studied during the years 1993-1994. The houses were investigated for visual signs of moisture by a surveyor, and observations of mould were reported by the occupants. A moisture problem was observed in 52% and a mould problem in 27% of the houses. Health data was collected by means of a postal questionnaire from 699 adults. Exposure to moisture was significantly associated with sinusitis, acute bronchitis, nocturnal cough, nocturnal dyspnoea and sore throat, and the exposed inhabitants had significantly more episodes of common cold and tonsillitis. Exposure to mould was significantly associated with common cold, cough without phlegm, nocturnal cough, sore throat, rhinitis, fatigue and difficulties in concentration. Building-related moisture or mould increased the risk of upper and lower respiratory infections and symptoms as well as of nonrespiratory symptoms. (+info)
Increased levels of markers of microbial exposure in homes with indoor storage of organic household waste.
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As part of environmental management policies in Europe, separate collection of organic household waste and nonorganic household waste has become increasingly common. As waste is often stored indoors, this policy might increase microbial exposure in the home environment. In this study we evaluated the association between indoor storage of organic waste and levels of microbial agents in house dust. The levels of bacterial endotoxins, mold beta(1-->3)-glucans, and fungal extracellular polysaccharides (EPS) of Aspergillus and Penicillium species were determined in house dust extracts as markers of microbial exposure. House dust samples were collected in 99 homes in The Netherlands selected on the basis of whether separated organic waste was present in the house. In homes in which separated organic waste was stored indoors for 1 week or more the levels of endotoxin, EPS, and glucan were 3.2-, 7.6-, and 4. 6-fold higher, respectively (all P < 0.05), on both living room and kitchen floors than the levels in homes in which only nonorganic residual waste was stored indoors. Increased levels of endotoxin and EPS were observed, 2.6- and 2.1-fold (P < 0.1), respectively, when separated organic waste was stored indoors for 1 week or less, whereas storage of nonseparated waste indoors had no effect on microbial agent levels (P > 0.2). The presence of textile floor covering was another major determinant of microbial levels (P < 0.05). Our results indicate that increased microbial contaminant levels in homes are associated with indoor storage of separated organic waste. These increased levels might increase the risk of bioaerosol-related respiratory symptoms in susceptible people. (+info)
HIV heterogeneity and proximity of homestead to roads in rural South Africa: an exploration using a geographical information system.
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objective To describe heterogeneity of HIV prevalence among pregnant women in Hlabisa health district, South Africa and to correlate this with proximity of homestead to roads. methods HIV prevalence measured through anonymous surveillance among pregnant women and stratified by local village clinic. Polygons were created around each clinic, assuming women attend the clinic nearest their home. A geographical information system (GIS) calculated the mean distance from homesteads in each clinic catchment to nearest primary (1 degrees ) and to nearest primary or secondary (2 degrees ) road. results We found marked HIV heterogeneity by clinic catchment (range 19-31% (P < 0.001). A polygon plot demonstrated lower HIV prevalence in catchments remote from 1 degrees roads. Mean distance from homesteads to nearest 1 degrees or 2 degrees road varied by clinic catchment from 1623 to 7569 m. The mean distance from homesteads to a 1 degrees or 2 degrees road for each clinic catchment was strongly correlated with HIV prevalence (r = 0.66; P = 0.002). conclusions The substantial HIV heterogeneity in this district is closely correlated with proximity to a 1 degrees or 2 degrees road. GIS is a powerful tool to demonstrate and to start to analyse this observation. Further research is needed to better understand this relationship both at ecological and individual levels, and to develop interventions to reduce the spread of HIV infection. (+info)
Chagas disease: from bush to huts and houses. Is it the case of the Brazilian Amazon?
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Two of the major problems facing the Amazon - human migration from the other areas and uncontrolled deforestation - constitute the greatest risk for the establishment of endemic Chagas disease in this part of Brazil. At least 18 species of triatomines had been found in the Brazilian Amazon, 10 of them infected with Trypanosoma cruzi, associated with numerous wild reservoirs. With wide-range deforestation, wild animals will perforce be driven into other areas, with tendency for triatomines to become adapted to alternative food sources in peri and intradomicilies. Serological surveys and cross-sectional studies for Chagas disease, carried out in rural areas of the Rio Negro, in the Brazilian Amazon, showed a high level of seropositivity for T. cruzi antibodies. A strong correlation of seroreactivity with the contact of gatherers of piacava fibers with wild triatomines could be evidenced. (+info)
Breast-feeding protects against infection in Indian infants.
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A retrospective study was undertaken at two isolated Manitoba Indian communities to determine whether the type of infant feeding was related to infection during the first year of life. Of 158 infants 28 were fully breast-fed, 58 initially breast-fed and then changed to bottle-feeding and 72 fully bottle-fed. Fully bottle-fed infants were hospitalized with infectious diseases 10 times more often and spent 10 times more days in hospital during the first year of life than fully breast-fed infants. Diagnoses were mainly lower respiratory tract infection and gastroenteritis. Gastroenteritis occurred in only one breast-fed infant. Breast-feeding was strongly protective against severe infection requiring hospital admission and also against minor infection. The protective effect, which lasted even after breast-feeding was discontinued, was independent of family size, overcrowding in the home, family income and education of the parents. Measures to achieve breast-feeding for virtually all infants, particularly in northern communities, should be given high priority. (+info)