Inhalation of fine particle

The possibility of lung problems due to inhalation of fine particles or flakes or fibers of fiberglass has often been raised. The extensive medical research so far reported has shown no consistent evidence of chronic health effects in workers who are exposed to man-made vitreous fibers. In some studies where massive doses of fine-diameter fibers were implanted into mice, cancer development in the pleura was noted. Also some animal studies involving injection of fibers into the trachae resulted in a minimal fibrosis. 

Hazard Avoid inhalation of fine particles. TLV (for respirable dust) 0.1 mg/m3. 

Caution Uranium and its salts ate highly toxic. Dermati -tis renal damage, acute necrotic arterial lesions, death may occur. Radiation hazard from inhalation of fine particles of approx Ip. n ol particles in Lung may be long-term carcinogenic hazard. See L. T. Fair hall Industrial Toxicology (Hafner. New York, 2nd ed., 1969) pp 129-13L... 

Oral uptake often results in vomiting, which reduces the amount of toxin that can be absorbed. Metal compounds can react with either the acid in the stomach or the alkaline environment of the intestine, and this can decidedly influence solubility. Before being distributed throughout the body, the metals pass through the liver, where often detoxification processes begin. The inhalation of fine particles can result in a direct and rapid transfer of soluble metal compounds into the blood, leading to a rapid transfer and onset of symptoms. Toxic quantities of metals can also be absorbed through mucous membranes. Cuta-... 

Thus, RDX intoxication involves gastrointestinal, central nervous system and renal effects. The potential routes of exposure are inhalation of fine particles or fumes, or ingestion because RDX is a high-melting solid and not very lipid soluble, skin absorption is very unlikely. Although the symptoms may be severe, deaths have apparently been quite few, and no permanent damage seems to have resulted among survivors... 

Pneumoconiosis is an interstitial pneunomia caused by irritation of the lungs during occupational exposure to dust particles. Silicosis is the most serious of these diseases and is contracted by inhalation of fine particles of silica over long periods of time in gold mines, tin mines, stone quarries, and during sand blasting. 

The primary hazard with crystalline silica is the development of silicosis due to the inhalation of fine particles (<10 pm). There are reports that the exposure to silica (or the existence of silicosis) is associated with an increase in the incidence of lung cancer the International Agency for Research on Cancer classifies silica in Group 2A probably carcinogenic to humans . The applicable governmental regulations in various countries should be consulted and followed. Also, various codes of practice, such as ASTME 1132 [28], Standard Practice for Health Requirements Relating to Occupational Exposure to Silica, and ANSI Z 88.2 [29], Practices for Respiratory Protection, may be consulted. 

Maynard et al. (2004) have discussed concerns about inhalation exposure by SWNTs becoming airborne during the handling. With sufficient agitation unrefined SWNTs can result in the entry of fine particles into the air at concentrations of up to 53 pg/rn1 (Maynard et al., 2004). 

In Section 3.5.3, dry powder inhalers have been referred to as breath-controlled devices. The efficacy of dry powder inhalation is a function of many factors, influencing the delivered dose of fine particles and the deposition of these particles in the respiratory tract. Figure 3.4 shows that DPI performance is influenced both directly and indirectly by the design of the inhalation system. The powder formulation, the dose (measuring) system and the powder disintegration principle have to be designed correctly for release of sufficient fine drug particles in... 

Preparations for inhalation aerodynamic assessment of fine particles. In European Pharmacopoeia, pp. I43-I52. European Pharmacopoeia, Strasbonrg, 1997. 

Occupationally, liver injury is most likely to occur following exposure to vapors of volatile halogenated hydrocarbons (such as chloroform, carbon tetrachloride, and bromobenzene), which may enter the bloodstream via the pulmonary route. However, hepatotoxins may enter the gastrointestinal tract, and hence the liver, in the form of fine particles. They are inhaled, then expelled from the bronchi or trachea into the oral cavity, and swallowed with saliva. 

Raabe, O.G. "The Generation of Aerosols of Fine Particles", Inhalation Carcinogenesis Academic Press,... 

Human Health Effects (Refs 4 thru 12, 21 27). Munitions workers have experienced acute RDX intoxication, mainly from inhaling the fine particles ingestion may have been a contributing factor. Troops have occasionally suffered symptoms of RDX intoxication following consumption of Composition C-4, a plastic... 

Bennett, F. S., Carter, P. A., Rowley, G., and Dandiker, Y. (1999), Modification of electrostatic charge on inhaled carrier lactose particles by addition of fine particles, Drug Dev. Ind. Pharm., 25, 99-103. 

Bennett, W.D., Zeman, K.L. (1998). Deposition of fine particles in children spontaneously breathing at rest. Inhal. Toxicol. 10 831 2. 

Recent work with insulin provides evidence that the total lung volume at the end of the delivery impacts the kinetics of absorption of this peptide delivery of fine particle insulin aerosol resulted in faster absorption with a higher plasma peak level in humans when the inhalation was done with a deep breath (close to vital capacity), as compared with a more shallow breath (about 50% of the vital capacity).The kinetics following the latter was similar to subcutaneous absorption of insulin. The exact reasons for this observation are unknown. However, the lung does have the above-described water channels that could expand during breathing. If the size of the peptide or protein molecule approaches the diameter of these channels, it would be expected that the channel expansion would lead to faster absorption. For molecules whose size exceeds the channel diameter, the lung volume does not play a role in their pulmonary absorption rate. ... 

Preparations for inhalation-aerodynamic aeesssment of fine particles. European pharmacopoeia 2005, (5.0), 247-250. 

Aluminum oxide is generally regarded as relatively nontoxic and nonirritant when used as an excipient. Inhalation of finely divided particles may cause lung damage (Shaver s disease). 

Human Health Effects (Refs 4 thru 12, 21 27). Munitions workers have experienced acute RDX intoxication, mainly from inhaling the fine particles ingestion may have been a contributing factor. Troops have occasionally suffered symptoms of RDX intoxication following consumption of Composition C4, a plastic expl containing 91% RDX Composition C-4 was chewed by soldiers to produce the high of ethyl alcohol, or it was used as a fuel for cooking. In the latter case, the victims may have inhaled the fumes or inadvertently introduced RDX into their food. Acute effects were seen... 

Jerrett M, Newbold KB, Burnett RT et al (2007) Geographies of uncertainty in the health benefits of air quality improvements. Stoch Environ Res Risk Assess 21 511-522 Kodavanti UP, Schladweiler MC, Ledbetter AD et al (2005) Consistent pulmonary and systemic responses from inhalation of fine concentrated ambient particles roles of rat strains used and physicochemical properties. Environ Health Perspect 113(11) 1561-1568 Kuenzli N, Jerrett M, Mack WJ et al (2005) Ambient air pollution and atherosclerosis in Los Angeles. Environ Health Perspect 113 201-206... 

Depending on the particle diameter, the density, and the geometrical shape, the inhalable fraction can reach different parts of the respiratory tract The proportion of the inhalable dust which is not exhalable is referred to as total inhalable dust Fine particles are exhaled only if no absorption in the respiratory tract occurs. The larger particles are deposited in the nasal-pharyngeal-larynx tract, the smaller particles can reach the bronchial tract, and the fine dust the alveolar region. 

The inhalation flow affects pulmonary deposition but not the properties of the aerosol delivered by a pMDI Conversely, the intrinsic properties of the aerosol emitted from a DPI—a breath-actuated device—are highly dependent on the inhalation effort of the patient (83), and the inhalation flow must always be sufficiently high to produce an aerosol containing the optimal amount of fine particles (72,84)... 

Inhaled steroids have a narrow therapeutic index and therefore it is essential that the particle profile is optimal, with a high proportion of fine particles and a low proportion of large particles. Moreover, inhaled steroids are relatively costly and thus the fraction of the nominal (labeled) dose delivered should be optimized. Inhaled steroids are normally given once or twice daily, and therefore portability is less of an issue than with bronchodilators. 

---