Inhalable airborne particles

An occasional common side effect of capsaicin exposure is bronchoconstriction, in asthmatic people, caused by inhaled airborne particles. In nonasthmatic people, this induces a cough. This is prevented by washing the skin surface where capsaicin was applied after 30-40 minutes of exposure. Chronic overdosage can cause chronic gastritis, kidney and liver toxicity, and neurotoxic effects. 

USP Sodium Taurocholate Reference Standard (Caution Avoid inhaling airborne particles.) Keep container tightly closed. Dry at 105° for 4 h before using. 

Primary infection usually results from inhaling airborne particles that contain M. tuberculosis These particles, called droplet nuclei,... 

When assessing exposure to allergens and toxins, liquid impingement, where bioaerosols are directly collected into a hquid, is widely used. BioSampler, was designed to collect inhalable airborne particles while minimizing the problems... 

Thomas R. G. (1972). An interspecies model for retention of inhaled particles, page 405 in Assessment of Airborne Particles, Mercer, T. T., Morrow, P. E. and Stober, W., Eds. (Charles C Thomas, Springfield, Illionis). 

So, a chemical attack will have its best effect an hour or so on either side of sunrise/sunset. Also, being vapors and airborne particles they are heavier than air so they will seek low places like ditches, basements and underground garages. This stuff won t work when it s freezing, it doesn t last when it s hot, and wind spreads it thin too fast. They ve got to get this stuff on you, or get you to inhale it, for it to work. 

Residents can be exposed to household products by accidental ingestion, skin contact, splashing into the eyes, and by inhalation of vapors or airborne particles. Exposures can be short-term, resulting from a single product use or spill, to long-term, from frequent product use or off-gassing of volatile components. 

The lining of the vestibule, which contains a zone of short stiff hairs (vibrissae), acts as a baffle system for filtering out large (>10 pm) airborne particles. The stratified squamous epithelium of the vestibule is resistant to dehydration and inhaled irritants and poorly permeable. Between the vestibule and atrium, there is a constriction known as the internal... 

Inhalation Exposure Inhalation is the absorption of a substance in the form of airborne particles during breathing. This occurs particularly when mixing and spraying a toxic substance, like pesticides. This exposure increases when working in confined or poorly ventilated areas. The chemical must be airborne to cause... 

Inhalation and direct skin contact are the most common routes of chemical exposure. The greatest exposure risk in handling potent compounds in an analytical laboratory therefore occurs when handling solid materials due to the potential to generate and inhale airborne dust particles of the compound. Once the potent material has been placed into solution, the airborne exposure risk is reduced and solutions of potent compounds may be handled in a manner similar to other nonpotent pharmaceutical compounds, assuming good laboratory practices are followed. Caution should be taken not to aerosolize the solutions since this could create an inhalation hazard. In addition, any sample solution spills should be adequately cleaned to prevent powder deposits of the compound from forming, which could potentially become airborne after the liquid has dried. 

Evaluation of the content of PGMs in airborne particles and dusts is important because of the possibility of their inhalation and accumulation in human lungs. Nanoparticles from autocatalysts can be transported into various parts of the environment (waters, plants, soils, and sediments) and transformed into more bioavailable species. There are data on the higher solubility of platinum from tunnel dusts than from inorganic species emitted from converters [30]. Distribution and accumulation of metals depend on traffic density, distance from the road, and meteorological conditions (wind, rain). The age of an autocatalyst and speed conditions directly affect the amount of nanoparticles released from catalytic... 

The hazard from inhaled uranium aerosols, or any noxious agent, is determined by the likelihood that the agent will reach the site of its toxic action. Two main factors that influence the degree of hazard from toxic airborne particles are the site of deposition in the respiratory tract of the particles and the fate of the particles within the lungs. The deposition site within the lungs depends mainly on the particle size of the inhaled aerosol, while the subsequent fate of the particle depends mainly on the physical and chemical properties of the inhaled particles and the physiological status of the lungs. 

In acute exposures, respiratory disease may be limited to interstitial inflammation of the alveolar epithelium, leading eventually to emphysema or pulmonary fibrosis (Cooper et al. 1982 Dungworth 1989 Stokinger 1981 Wedeen 1992). In studies of the pulmonary effects of airborne uranium dust in uranium miners and in animals, the respiratory diseases reported are probably aggravated by the inhalable dust particles (the form in which uranium is inhaled) toxicity because most of the respiratory diseases reported in these studies are consistent with the effects of inhaled dust (Dockery et al. 1993). In some of these instances, additional data from the studies show that the workers were exposed to even more potent respiratory tract irritants, such as silica and vanadium pentaoxide (Waxweiler et al. 1983). 

Spumy KR. In Mercer TT, Morrow PE, Stober W, eds. Assessment of Airborne Particles Fundamentals Applications and Implications to Inhalation Toxicity. Springfield, IL Charles C Thomas, 1972 54. 

The powders and crystals used in this unit are not hazardous. However, caution students to handle the chemicals according to the directions. This will prevent students from creating excessive airborne particles that could be inhaled. 

Inhalation is actually a less Important route of entry than assumed by CDC, if other data are considered. For example, the EPA has estimated that the average concentration of total suspended particulates (TSP) In Missouri Is about one-half the level assumed by CDC, or about 0.070 mg/m (32.33). Secondly, only a fraction (about 30%) of the total amount of airborne dust Is respirable (less than 10 pm aerodynamic diameter) (32). The percentage of TSP which Is respirable has been estimated by EPA to be no more than 50% (2). Also, the assumption that all of the airborne particles are derived from dioxin-contaminated soil Is overly conservative. Actually, about 50% of the Inhaleable particles are respirable and the remainder are between 10 and 50 pm. Further, about 83% of the non-respirable particles are from crustal material (e.g., soil) and only 47% of the respirable particles are from soil (32). Larger studies conducted by the U.S. EPA have suggested that the portion of Inhaleable dust due to soil can often be much less (34). 

Halogenated (mostly Cl and Br) biocides (such as hypochloride or DBDMH, see Tab. 6.3-1) are the most commonly used chemicals for sanitizing water. They are strong oxidizers and, as dust and products of decomposition (below), irritate respiratory tracts. Therefore, airborne, inhalable fine particles and all dust must be avoided. This is also true for non-chlorine (or bromine) oxidizers that are used for the same... 

Inhalation and ingestion (of water, food, paint, soil and/or dust) are the primary routes of human exposure to lead (OECD, 1993). Percutaneous absorption is minimal in humans. The absorption of lead from air to blood involves two processes the deposition of airborne particles in the respiratory tract and the absorption and clearance from the respiratory tract into the circulation. The respiratory deposition of airborne lead is in the range of 30-50% and varies with particle size, chemical speciation, solubility in body fluids and ventilation rate. Higher deposition rates may occur with larger particles, but this deposition takes place in the upper respiratory tract. The smaller particles of inhaled lead (generated by automobile exhaust) are almost (>90%) completely absorbed after deposition in the lower respiratory tract (WHO, 1995). 

An important late sequela of mustard inhalation is a tracheal/bronchial stenosis that necessitates bronchoscopy and other procedures.77 Mustard has been reported to create a long-term sensitivity to smoke, dust, and similar airborne particles, probably as a result of clinically inapparent broncho-spasm.5888... 

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