Indoor Atmospheric Compounds

HCHO and HCOOH are important indoor corrosion stimulants that can originate from tobacco smoke, combustion of biomass, adhesives, and plastics. In general, the concentration of these stimulants is lower indoors than outdoors, except for ammonia and the organic species that usually have a higher concentration indoors than outdoors. This higher level is the result of anthropogenic activity. 

The concentrations of pollutants foimd in both indoor and outdoor atmospheres can vary greatly as a result of the type of atmosphere and/or the geographic location. It is almost impossible to provide a specific range for a specific location unless air samples are taken and analyzed. Listed below are some t)/pical indoor and outdoor ranges of inorganic pollutants as found in the United States. 

CI2 5% of HCl levels except where local source exists 0.004-0.015 

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From the above it can be concluded that the risk for lung cancer induction from chronic indoor exposure to Rn-d is unlikely to be higher than 1.10 4/mSv. in order to understand the magnitude of this risk it has to be emphasized that man can be exposed to a multitude of different hazardous materials in the indoor atmosphere besides Rn-d, such as formaldehyde, nitrogen dioxide, carbon monoxide, nitrosamines, polyaromatic hydrocarbons, volatile organic compounds, asbestos and pesticides (Gammage and Kaye, 1985). 

Air quality in homes and workplaces is affected by human activities, construction material, underground minerals, and outside pollution. The most common indoor pollutants are radon, carbon oxides, nitrogen oxides, tobacco smoke, formaldehyde, and a large variety of organic compounds. Indoor atmospheres can also be contaminated with fine particles such as dust, aerosols (from spray cans), fungal spores, and other microorganisms. 

Information on levels of 2-butoxyethanol in air is very limited. 2-Butoxyethanol was reported among 34 major eompounds identified in high-volume air samples at a semi-rural site in the United Kingdom however, no eoneentrations were given (Welch and Watts 1990). Analysis of data from the National Ambient Volatile Organic Compounds (VOCs) Database indicates that, for 14 samples, the daily arithmetic mean and median indoor atmospheric concentrations of 2-butoxyethanol in a non-industrial office setting were 0.214 ppb (v/v) (1.03 g/m ) and 0.075 ppb (0.36 g/m ), respectively (Shah and Heyderdahl 1988 Shah and Singh 1988). 2-Butoxyethanol was found in only 1 of 6 samples of indoor air from 14 homes in northern Italy, at a concentration of 1.7 ppb (8 g/m ) (DeBortoli et al. 1986). 

Indoors Atmospheres in Houses and Certain Metals and Metal Compounds as Suspected ECD Agents... 

It is known that, when certain metal compounds are present in air at concentrations above the levels of homeostatic regulation, they can act as a health hazard. The most common metals and metal compounds that can be found in the indoors atmosphere, are mainly those of antimony, lead, (methyl) mercury, and cadmium, which can exist in plastics as additives (mostly found and used as stabilisers). These are believed to disrupt the endocrine system by causing problems in steroid production. The fate of these metal and metal ions has been more extensively studied for the lead and lead-based compounds, however, other metals have been studied much less than others. 

Analysis of corrosion products on copper, zinc, nickel, and iron specimens that had been exposed to various benign corrosive indoor atmospheres shows large amounts of infrared bands from carboxylate ions such as formate, acetate, and oxalate. This may be an indication of a stronger influence of carboxylic acids and other organic compounds under benign conditions than in more aggressive atmospheres. 

The behaviour of PCT is similar to that of PCB [68, 118]. Monochlorobenzene and the dichlorobenzenes are sufficiently volatile for inhalation to be a significant route of exposure, at least in the workplace or other indoor atmospheres, they will also be exhaled when exposure ceases. All other compounds are excreted in the urine, after metabolism to hydroxyl compounds, as glucuronide or other conjugates. Metabolism proceeds via an arene oxide (Fig. 3), as a result of mixed function oxidase activity in the liver compounds containing two adjacent unsubstituted carbon atoms form arene oxides most readily. Chlorobenzenes have been shown to be ex-... 

Total volatile organic compounds (TVOCs) in Indoor and Outdoor Urban Atmospheres at a Terai Region Of Northern India... 

Sauer, T.C., Jr, Sackett, W.M. Jeffrey, L.M. (1978) Volatile liquid hydrocarbotrs in the surface coastal waters of the Gulf of Mexico. Marine Chem., 1, 1-16 Seifert, B. Abraham, H.-J. (1982) Indoor air concentratiotrs of benzene and some other aromatic hydrocarbons. Ecotoxicol. environ. Saf, 6, 190-192 Shah, J.J. Heyerdahl, E.K. (1988) National Ambient Volatile Organic Compounds (VOCs) Data Base Update (EPA 600/3-88/0 lOA), Research Triangle Park, NC, Environmental Protection Agency, Atmospheric Sciences Research Laboratory ... 

For gas-phase sensors, both remarkable selectivity and very low LOD are important. Sensors featuring MIP recognition combined with SAW transduction can meet these requirements. The MIP-PZ chemosensors operating in gases are devised for two main applications, namely for indoor gas inspection and online monitoring of volatile organic compounds. The latter is essential to protect humans from threats of environmental atmospheric pollutants. 

Crump, D.R. (1995) Volatile Organic Compounds in Indoor Air, in Volatile Organic Compounds in the Atmosphere (eds R.E. Hester and R.M. Harrison), The Royal Society of Chemistry, p. 118. 

Weschler, C.). (2003) Indoor/outdoor connections exemplified by processes that depend on an organic compound s saturation vapor pressure. Atmospheric Environment, 37, 5455-65. 

Meininghaus, R., Salthammer, T. and Knoppel, H. (1999) Interaction of volatile organic compounds with indoor materials-a small-scale screening method. Atmospheric Environment, 33, 2395-401. 

Molhave, L and Thorsten, M. (1991) A model for investigation of ventilation systems as sources for volatile organic compounds in indoor dimate. Atmospheric Environment, 25A, 241-9. 

Kjaergaard, S.K., Molliave, L. and Pedersen, O.F. (1991) Human reactions to a mixture of indoor air volatile organic compounds. Atmospheric Environment, 25A (8), 1417-26. 

Air quality is important from both a health and a safety perspective. In the USA, the National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration set limits of exposure to over 2000 different chemicals or classes of respiratory irritants [11, 12], Many of the compounds that are monitored indoors are of similar interest to outdoor assessment, such as in the atmosphere and stratosphere. VOCs emitted from industrial operations are continuously monitored as required by US and local Environmental Protection Agencies. Power plants and waste incinerators are required to follow emission guidelines for harmful combustion gases, including CO and NO, as well as other combustion by-products, including polycyclic aromatic hydrocarbons, phenols, and hy-... 

Biocides. The attack of fungi on the several components of a vinyl formulation may manifest itself as an unsightly growth looking much like dirt or may result in the formation of discolored areas (yellow, pink, blue, clear) on the finished goods. Outdoor exposure, indoor exposure in humid atmosphere, soil burial or contact, and electrical insulation compounds are typical areas where biocide addition is indicated. Since most commercial biocides are heavy metal derivatives, care must be taken to assess their effect on heat and light stability and compatibility with the vinyl system in which they are used. 

In ambient air, the primary removal mechanism for acrolein is predicted to be reaction with photochemically generated hydroxyl radicals (half-life 15-20 hours). Products of this reaction include carbon monoxide, formaldehyde, and glycolaldehyde. In the presence of nitrogen oxides, peroxynitrate and nitric acid are also formed. Small amounts of acrolein may also be removed from the atmosphere in precipitation. Insufficient data are available to predict the fate of acrolein in indoor air. In water, small amounts of acrolein may be removed by volatilization (half-life 23 hours from a model river 1 m deep), aerobic biodegradation, or reversible hydration to 0-hydroxypropionaldehyde, which subsequently biodegrades. Half-lives less than 1-3 days for small amounts of acrolein in surface water have been observed. When highly concentrated amounts of acrolein are released or spilled into water, this compound may polymerize by oxidation or hydration processes. In soil, acrolein is expected to be subject to the same removal processes as in water. 

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