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The main sources of pollution, related pollutants, their emission rates and ways of liberating indoor air are presented. Health symptoms in air spaces with different ventilation systems and risks associated with particular sources are compared. Also, different sampling and analytical techniques and source characterization methods are described. The advantages and shortcomings of the five basic approaches to indoor air monitoring are discussed. Special stress is put on passive samplers whose types theories and areas of application and newest designs are given.
Endotoxin, a characteristic external fraction of the outer membrane from Gram-negative bacteria, continuously shed into the environment, is considered as an important risk factor for human health. Our purpose was to study the bacterial species contaminating healthy working environments. Airborne, working surfaces and carpet dust samples were collected from 25 offices. Bacterial species were identified with biochemical ApiSystem® strips. Endotoxin concentrations in settled dust were measured with the kinetic chromogenic Limulus assay. The airborne bacterial level varied from 44-2,511, with a median of 277 cfu/m3. Bacterial contamination on surfaces ranged from 1-1000, with 33 cfu/25 cm2 as median value. On carpets, bacterial concentration ranged from 0.73-185 x 105 cfu/g, with 7.28 x 105 cfu/g as median value. Endotoxin concentration varied from 4.6-116.2 EU/mg, with a median of 20.3 EU/mg. Altogether, 501 bacterial strains were isolated. The species variability was greater in Gram-negative bacteria than in Gram-positive cocci with 41 versus 34 various species. In conclusion, people working in healthy offices can be exposed to large concentrations of airborne and dust bacteria and related endotoxin concentrations, giving a risk of work-related diseases.
A total of 69 isolates of yeasts were recorded in the indoor air of the school buildings: 43 in heated rooms and 26 in unheated rooms. Perfect stages prevailed. Fungi isolated in our study belonged to 39 species. These were mostly monospecific isolates although five two-species isolates were noted. Differences in the properties of physiological characters of fungi isolated in both study seasons were observed. As indoor and outdoor air does not mix during the heating season, a specific substrate for prototrophic, non-fermenting yeastlike fungi forms. Acid production allows fungi to dissolve inorganic compounds in building structures and to release needed microcomponents. Abilities to produce carotenoid pigments are clearly promoted in yeast-like fungi living indoor. This may be related to the accumulation of compounds that are indirect stages in the cycle of biosynthesis of carotenoids or a surplus of oxidizing compounds.
This survey work summarizes the generation of indoor air pollutants (IAPs) through household products and activities and also the probable health symptoms of IAPs were discussed through questionnaire in the residential buildings of urban and semi urban area when compared to rural (control) area by door to door survey. The IAPs are categorized as physical, chemical and biological and surveyed as per the product(s) usage in the closed room of buildings. The survey results of IAPs generated from household products and activities, these are asbestos, fine particulate matters and ash as physical pollutants. The chemical pollutants are carbon mono and di oxide gases, phthalates; DDT, chlordane, heptachlor, o-phenylphenol; PBDEs, Formaldehyde, Other Aldehydes, lead, benzene, chloroform, para-dichlorobenzene, methylene chloride, perchloroethylene, styrene, benzene, formaldehyde, terpenes, styrene, phthalate esters, toluene, Propellant, pesticides, PAH, NOx, acrylamide, VOCs, acetone, HCl gas and biological pollutants are bacteria, fungi, viruses, house dust mites, animal dander; cockroaches, microbial spore. In respect to established health impact data, the health symptoms were recorded after survey in two areas viz. urban and semi urban area. The health symptoms were recorded as eye, nose, and throat irritation; allergic reactions, respiratory irritation, aggravated asthma, influenza and other infectious diseases may be the generation of IAPs. The urban and semi urban area are compared with rural (control) area in which no symptoms were found as per discussion. In the present survey it was concluded that the generation of IAPs may from household products and activities in the urban and semi urban area due to less ventilation facilities when compared to rural (control) area. This is a preliminary observation, further researches are needed in relation to measurement of physical, chemical and biological indoor pollutants in closed room of residential buildings and also health hazards study of residents by haematological, biochemical, enzymological and genotoxicological parameters.
The main aim of the study was to compare rearing effect of calves kept outdoor in individual hutches and indoor in group pens. During the experiments following measurements were taken: body weight, daily and monthly gains and mortality. Study was conducted on 90 calves from 5th to 90th days of age and measures were taken in 3 seasons - spring, summer - autumn and winter. All calves were fed with the same feed and according to the same schedule. Results reviled that during first month calves from both groups achieved the same daily gains. However, older calves kept indoor characterized themselves by better gains and body weight. During the experiment only 2 claves were lost (mortality rate - 2.2%).
Caring for indoor air quality (IAQ) in so-called non-industrial areas has become increasingly common. Because of people's awareness of hazards related to the presence of different substances in indoor air. A review with 103 references concerning the presence of organic compounds in non-industrial indoor environments is discussed. The main sources of indoor air pollutants are presented. Topics discussed also include: total volatile organic compounds (TVOC) concepts in IAQ evaluation, concentrations of organic compounds in indoor and outdoor air, and the influence of outdoor air on indoor air quality expressed as ratios of indoor (I) to outdoor (O) concentrations (I/O).
School buildings typically serve a number of functions simultaneously, owing to which they seem to be especially exposed to the expansion of fungi with wide enzymatic capabilities, including fungi of the genus Penicillium. In total, 34 isolates belonging to 20 species were obtained within two schools. The most frequently isolated species included: Penicillium chrysogenum, P. waksmanii, and P. citrinum. Over 65% more fungi were isolated in the heating season than when the heating was off. This period was also characterized by an almost threefold greater taxonomic spectrum. Especially in the heating season, the prevalence and species spectrum of the fungi of the Penicillium genus in school buildings should be constantly monitored due to their environmental plasticity as well as toxigenic, allergenic and antibiotic properties.
A study on indoor air microbiological contamination in various rooms of university buildings in Poznań, Poland, is presented. Investigations were conducted in the period September-October 2002 and the same period in 2003. Air samples were taken twice a day: in the morning and in the afternoon. In all of the tested places a multiple growth of bacteria and significant increase of mould spores was observed in afternoons. The predominant bacteria and moulds isolated from investigated air samples were: Staphylococcus spp., Micrococcus spp., Serratia spp., Aspergillus spp., Penicillium spp., Rhizopus spp., Cladosporium spp. and Alternaria spp. Among these microbes the presence of pathogenic and strongly allergenic microorganisms was detected.
Indoor environment is significant with respect to human health especially if it is concerned when the building is v. Aim of very old. In the present study was to assess the presence of airborne fungi at an old building in Kolkata India where lots of tourists are exposed every day. Residence of famous Nobel laureate poet Rabindranath Tagore (built in the 18th century and presently used as a famous museum) in Kolkata, West Bengal was selected for this study and the indoor fungi from different room of the museum were assessed by using exposure plate technique. Humidity, temperature, wind speed and illuminance were also measured by hygrometer, thermometer anemometer and lux-meter respectively. The fungal species isolated from the air samples of different rooms were Aspergillus sp., Penicillium sp., Paecilomyces sp., Trichoderma sp, Alternaria sp Verticillium sp, Fusarium sp, Cladosporium sp, Yeast, Curvularia sp. and Helminthosporium sp. among them, Aspergillus sp. (71.4% at monsoon at library), Penicillium sp (57% at summer at library), Paecilomyces sp.(91% at monsoon at manuscript room) are mostly dominated pathogens, which may harm the workers and visitors of the museum. No significant correlation among colony forming unit of fungi with illuminance, wind speed and temperature in the tested indoor environment was noted whereas, the humidity in indoor environment played a crucial (P<0.05) role. Round the year humidity control may be required for maintaining healthy environment.
A total of 111 isolates of yeast-like fungi and yeasts belonging to 40 species of 19 genera were identified in indoor air and outdoor air. Only one species, Kluyveromyces marxianus, was recorded in both types of air and seasons (spring and autumn). Kluyveromyces lactis and Yarrowia lipolytica, a species having the greatest symbiotic abilities, dominated in indoor air and outdoor air, respectively. Intensely used rooms, especially those with limited access of air, have the broadest range of species of yeast-like fungi. A comparison of both habitats shows that school rooms pose a greater epidemiological risk of yeast-like infections than outdoor air. The indoor as well as outdoor mycobiota undergoes phenological changes although it is determined by other biotic and abiotic factors.
As people spend most of the time in closed spaces (flats, workplaces, schools etc.), the indoor air has been researched for many years all over the world. Particulate matter (PM) is one of the most often examined pollutants in the indoor and outdoor air. The following study presents the facts about PM in closed spaces and the most often taken actions. The least known aspects related to the indoor air pollution with PM are demonstrated. The indoor space of various service and office buildings/facilities (not related to production, i.e. offices, shops, beauty parlours, restaurant kitchens, restaurants, pubs etc.) seem to be an unrecognized area in the air pollution studies. Importantly, a great number of people work in such spaces all over the world and thus spend there a large part of their lives.
W pracy przedstawiono wyniki pomiarów stężenia mikroorganizmów w pomieszczeniach szpitali położonych w zwartej zabudowie miasta i poza miastem. Omówiono wpływ różnych czynników na stężenie bakterii i grzybów w pomieszczeniach szpitala.
W powietrzu stołówki studenckiej metodą sedymentacyjną określono liczbę bakterii mezofilnych tlenowych, drożdży i grzybów pleśniowych, a wyizolowane grzyby poddano identyfikacji jakościowej. Badaniami objęto powietrze w różnych obszarach stołówki, wydzielonych według przeznaczenia i odbywających się tam czynności. Przeprowadzono dwanaście serii badań (w różnych terminach), przy czym w każdej serii oznaczenia wykonywano w godzinach rannych i popołudniowych.
Polskie normy (PN) z 1989 r. dotyczące badań skażenia mikrobiologicznego powietrza atmosferycznego w dużym stopniu uległy dezaktualizacji, natomiast polskich norm dotyczących badania zanieczyszczeń biologicznych w pomieszczeniach wewnętrznych brak. Utrudnia to, a czasem uniemożliwia porównywanie uzyskiwanych wyników między sobą. W pracy pokazano na przykładach skalą problemu.
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