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PubMed1986

[Microbial contamination of the air in the housing of laying hens].

Studied were buildings of one and the same design, sizing 92/12/3.5 m. Building A of mechanical ventilation through negative pressure housed 9,000 layers of the White Leghorn breed, and building B of ventilation with equated pressure, providing the same debit per kg biomass, housed 20,000 layers. The air in the buildings, in the close surrounding as well as the feed and soil were investigated with regard to the total counts of organisms as cultured in meat and peptone agar and with regard to the individual counts of coli bacteria, microscopic fungi and hemolytic cocci, and Salmonellae. It was found that the microbial contamination of air on the productional premises and of atmospheric air closely surrounding the buildings, was higher in building A. There were differences in the microflora of the air at the level of the individual stories in building B. The differences in the microbial contamination of air between the two buildings was the result of reconstructions concerning the ventilation system as well as of making it more effective.

Air Microbiology↗
PubMed1985

[Changes in the physical environmental factors in modern buildings related to the use of polymeric construction materials].

The polymeric materials are used on a large scale in building and furnishing of modern edifices. However, in spite of the doubtless positive effect there are a number of important hygienic problems, related to the ability of these new materials, at unregulated and not controlled usage, to cause unfavourable changes in the parameters of the environment and through them to affect the health and spirits of the inhabitants. The basic hygienic problems in the application of polymeric building materials /PBM/ are derived from the elimination of harmful chemical substances from the latter. Besides of great importance are the changes in the physical parameters of the environment in the premises of the edifices, arising from the accumulation of static electricity on the surface of the PBM, the aggravated thermal technical characteristics of some materials, etc. The results of the hygiene investigations for thermal protective properties of different types of PBM, used as floor covering and their effect on the thermal metabolic processes and colds of the inhabitants are pointed out. The biological effect of static electricity and the dependence of the electrification of the materials on the composition and the physico-chemical nature of the materials and some microclimatic parameters and other exploitation conditions are clarified. Recommendations are given for the preliminary hygienic control of these materials, in order to avoid the aggravation of the parameters of the environment in the modern buildings.

Chemical Phenomena↗
PubMed1985

[Respiratory function study of workers engaged in vinyl chloride and polyvinyl chloride manufacture].

A hygienic evaluation is made on the work conditions in the production of vinyl chloride and polyvinyl chloride. Studies were carried out on 516 workers after the following indices: vital capacity /VC/, forced expiratory volume per sec. /FEV1/, peak expiratory capacity /PEC/, maximum expiratory capacity 75 /MEC75/, maximum expiratory capacity 50 /MEC50/ and maximum expiratory capacity 25 /MEC25/. It was established that 33.13% of the workers were with ventilation disturbances. The most frequently met was the obstructive syndrome of ventilation insufficiency. The infringements were most often in workers with length of service up to 1 year.

Adult↗
PubMed1985

Harvard Air Pollution Health Study in six cites in the U.S.A.

The Harvard Air Pollution Health Study has been a ten year prospective study of respiratory symptoms and pulmonary function of children and adults living in six U.S. communities. Indices of acute and chronic effects of air pollution exposures have been studied. Evidence is presented for adverse effects of ambient and indoor air pollution on children. Relationships between ambient TSP concentrations and hospital emergency room admissions, temporary decreases in pulmonary functions and prevalence of community bronchitis all indicate a slight adverse effect. Refinements of these relationships will occur when fine fraction and acid sulfate aerosol concentrations are incorporated into the health analysis. Exposures to cigarette smoke at home are associated with increased reported respiratory symptoms in children. There is a negative relationship between maternal smoking and age and sex adjusted height for children. Results from indoor and personal exposure studies have lead to the design of an acute symptoms and indoor air pollution study. Between 1985 and 1988 1800 children will be tracked for a year while respirable particles, nitrogen dioxide, water vapor and air exchange will be measured in their homes. Using continuous sulfate/sulfuric acid monitors built at Harvard, we are characterizing the magnitude, duration and frequency of acid aerosol events in each of our study cities. This information will be utilized in the analysis of the respiratory symptom data. The Harvard Air Pollution Health Study is providing information on the relationship among health variables and air pollutant exposures. In addition, this study will add to our understanding of lung growth and aging and the risk factors associated with chronic respiratory disabilities.

Adult↗
PubMed1985

Passive smoking--a new target of epidemiology.

Health consequences of passive smoking has thus emerged as a new target of epidemiological research and control of such important diseases as cancers of lung and nasal sinus, brain tumors, cancer of all sites and ischemic heart disease. The 16 years follow-up results of a large scale cohort study for 91450 non-smoking wives revealed significant and consistent dose-response relationships with the risk of each of these diseases and the extent of husband's smoking. The consideration of influence of passive smoking must be quite important if we aim to effectively control these diseases.

Adult↗
PubMed1985

Measurements of carbon monoxide and nitrogen dioxide in British homes using unflued heating or cooking appliances.

Measurements of Carbon Monoxide (CO) and Nitrogen Dioxide (NO2) were made in three kitchens, two with gas cookers and one all electric, and two living rooms, one heated by a portable butane heater and the other by a paraffin stove. The measurements were taken whilst the homes were in normal use and the occupants kept a diary of when specific appliances were used. Measurements of NO2 were made simultaneously by chemiluminescence and by diffusion tubes. The accuracy of the diffusion tube measurements relative to the chemiluminescent standard was estimated as +/- 10% and the precision less than or equal to 300 ppb. hr. Results from diffusion tubes were used to indicate the distribution of NO2 throughout other rooms in the house. At the all electric house the CO and NO2 concentrations were very similar to the expected outdoor levels. In all the other houses NO2 levels exceeded typical outdoor concentrations measured in Central London and in the paraffin heated house and one gas cooking house median CO concentrations exceeded these measured at the curbside of a very busy road in Central London. The living room concentrations of NO2 where the paraffin heater was in use were elevated for long periods. Analysis of the decay of pollutant concentration in one kitchen yielded an effective deposition velocity for NO2 of 3 X 10(-5) m s-1. The magnitude of the CO and NO2 concentrations measured in this survey confirms that indoor air pollution should be taken into account when assessing overall public exposure to air pollution.

Carbon Monoxide↗
PubMed1985

Personal exposure to nitrogen dioxide and its relation to indoor and outdoor air quality.

An estimating equation of annual geometric average of personal NO2 exposure was proposed. The average could be calculated from three variables, that is, personal NO2 exposures in one winter and one summer month and ratio of winter period in a year. Ten housewives living in Suginami Ward, a residential area in Tokyo, were chosen as subjects of this study. They were asked to measure daily averages of the personal NO2 exposures with a filter badge. Measurements were performed on consecutive seven days in every month from January to December of 1982 for a total of 84 samples per person. Their activities, the amount of fuel consumption and other living conditions were recorded at the same time. Outdoor NO2 concentrations and maximum, minimum and average temperatures were also measured at the center of their living area. The personal NO2 exposure and its seasonal variation were found to depend mainly on the type of space heaters, frequency of ventilation fan usage in a kitchen, and the amount of fuel consumption.

Air Pollutants↗
PubMed1985

Scandinavian experiences with indoor air pollution.

The building illness syndrome (BIS) with complaints about dryness and irritation of the mucous membranes of the eyes, nose and throat, and headaches is very common in Scandinavian buildings. The causes for BIS may be psychosocial, biological, physical or chemical factors in the indoor environment. Of these the chemical factors are considered to be the most important. BIS can be caused by formaldehyde, but the main sources of this emission are now controlled in the Scandinavian countries. As BIS complaints still are common, organic gases and vapors are considered to be the most important cause of BIS today. These gases and vapors are emitted from many building materials, and mixtures of these have been shown to be irritating in concentrations about 5 mg m-3, a concentration which is often found in new buildings. It is still an unsolved problem if BIS is due to the mixture of the organic gases and vapors themselves, or decomposition products in low concentrations, as for example peroxyacetyl nitrates known from outdoor air pollution. Irrespective of the cause, the rational approach would be a reduction of the emissions of organic gases and vapors from building materials or an increase of ventilation rates. The latter solution is not desirable due to the economic burden and to the need for energy conservation. We therefore suggest that building materials should be tested for emission of pollutants, so that materials emitting high concentrations of toxic substances can be identified and replaced by materials emitting less toxic substances and with emission of a lower rate.

Air Pollutants↗
PubMed1985

Indoor air pollution due to tobacco smoke under real conditions. Preliminary results.

A short review exploring the generation and composition of tobacco smoke is given. Experimental arrangements used to record sidestream smoke are critically discussed. Data from own experiments in a tobacco smoke polluted office room were presented and discussed. These data include nicotine, ammonia, formaldehyde, acetaldehyde, hydrogen cyanide, CO, NO and NO2. First results about the diameter of the particles in the smoke polluted room were also given. By the aid of the RINGOLD's equation the COHB content on basis of the CO-values of exhaled breath of active and passive smokers were determined. Data about the nitrosamine content in the air of the room during the smoke tests were also given and discussed.

Carbon Monoxide↗
PubMed1985

Irritating and annoying effects of passive smoking.

The acute irritating and annoying effects have been investigated in field and laboratory studies in relation to the concentration of some smoke components in the air. At the workplace 30 to 70% of the indoor CO, NO and particle concentrations are due to tobacco smoke; 25-40% of the employees are disturbed and annoyed by smoke, one quarter suffers from eye irritations at work. Subjective eye, nose and throat irritations and eye blink rate increase with increasing smoke concentration as well as with increasing exposure duration. Irritations are mainly due to the particulate phase of environmental tobacco smoke, whereas the gas phase is to a large extent responsible for annoyance. It is concluded that an average healthy person can be exposed to an acceptable cigarette smoke level which produces a carbon monoxide concentration of 1.5 to 2.0 ppm. Above these limits, counter-measures to protect passive smokers are necessary. The required fresh air supply values are presented.

Blinking↗
PubMed1985

Stability of tobacco smoke odor in enclosed spaces.

During each of five experiments, four sedentary subjects smoked a total of 8 cigarettes during one hour while occupying an odor test chamber. The air temperature was 20-22 degrees C and the relative humidity was 35-50%. During the entire test period (6 h) the odor intensity in the chamber was evaluated by judges. After smoking ceased, the odor intensity continued to rise for one or two hours and then remained constant in a way that is characteristic of unreactive contaminants.

Climate↗
PubMed1985

Investigations into the relations between respiratory illness in children, gas cooking and nitrogen dioxide in the U.K.

In 1977 an association was reported between the prevalence of respiratory illness and use of gas for cooking at home in a national sample of six to 11 year olds living in England and Scotland (p less than .10). Other variables such as social class and number of cigarette smokers at home did not seem to explain the association. As the gas cooker is an unflued appliance emitting a variety of pollutants during gas combustion it was suggested that indoor air pollution might explain the finding. Nitrogen dioxide (NO2) was suspected so a series of studies was conducted to investigate the distribution of levels of NO2 in the home, the relative contribution of sources of NO2 to indoor exposure and the relation between respiratory illness in six to 11 year olds and levels of NO2 in the home. The gas cooker was found to be one of the main sources of NO2 in the home. Winter weekly averages in kitchens with gas cookers had a mean of 112.2 ppb (n = 428, range 5-317 ppb). Levels in electric cooking kitchens were significantly lower (n = 87, mean 18 ppb, range 6-188 ppb). Studies of health indicated a relation between respiratory illness and bedroom levels of NO2 over the range 4-169 ppb (p .10). Results for living room levels of NO2 suggested a similar but non-significant relationship (p greater than .10). No relation was found for kitchen levels of NO2. For schoolchildren any effect on health from indoor NO2 is likely to be weak. However other sections of the population such as infants and the elderly who may spend more time indoors and are particularly susceptible to respiratory illness need to be studied to assess fully the impact that NO2 may be having on health.

Child↗
PubMed1985

A plan of the comprehensive study on indoor pollution and its health effects by the Aichi Prefecture, Japan.

In order to study the level and nature of the indoor pollution and its possible health effect the Department of Public Health of the Aichi Prefecture in Japan is planning to conduct a comprehensive study on indoor pollution. An outline of this study is presented in this report. The study will consist of measurements of the indoor pollution and health surveys for a sample of 10 large buildings and 75 houses involving 2,000 persons for the former and 1,000 three year old children and their mothers for the latter. The major survey items on the indoor pollution are measurements of suspended particles, CO, CO2, NO2, formaldehyde, falling and floating bacteria and fungi, mutagenicity, types of air cleaners, air conditioners and ventilators, and the number of smokers etc. The major health survey items are a questionnaire survey on respiratory diseases, pulmonary function tests, chest X-ray test, and measurement of urine hydroxyproline concentration. This comprehensive study on indoor pollution will be conducted for 5 years beginning the fiscal year 1984.

Air Pollution↗
PubMed1985

Relationship between parental smoking and respiratory diseases of three year old children.

In order to study the effect of the indoor pollution, particularly by parental smoking, on respiratory diseases of children, the relationship was examined between smoking by family members, use of various types of stoves and air conditioners, and the prevalence rate of respiratory diseases in 7,916 three year old children who, for health check up, visited the Chita Public Health Center located in the Aichi Prefecture in 1978-1979. Results of this study suggested that among various sources of the indoor pollution, smoking by mother had the strongest effect on respiratory diseases, especially asthmatic bronchitis of young children, while the use of various types of stoves including non-ventilated kerosene stoves was not related significantly to the prevalence rate of respiratory diseases of those children except an increased rate of frequent common cold in children of households having an air conditioner(s).

Asthma↗