Alkaline airborne

Haapala, H., Goltsova, N., Pitulko, V., Lodenius, M., 1996. The effect of simultaneous large acidic and alkaline airborne pollutants on forest soil. Environ. Pollut. 94, 159-168. 

Potassium biduoride crystals may break down to a fine white powder that is readily airborne. In this form, the salt is quite irritating to the nasal passages, eyes, and skin. Therefore, the hands and eyes should be protected and acid dust masks should be worn while handling, as an acid duoride KHF2 can cause superficial hydroduoric acid-type bums. Areas of skin that have been in contact with potassium biduoride should be washed as soon as possible with mildly alkaline soaps or borax-containing hand cleaners. If there has been contact with the eyes, they should be washed well with water and a physician should be consulted. 

The analysis of tetramethylammonium hydroxide (TMAH) solutions manufactured by SACHEM Inc. of Cleburne, Texas, includes the determination of trace elements. These elements cause less-than-optimum performance of integrated circuit boards manufactured by SACHEM s customers that use these solutions in their processes. Alkali and alkaline earth metals (e.g., Li, Na, K, Mg, Ca, and Ba) can reduce the oxide breakdown voltage of the devices. In addition, transition and heavy metal elements (e.g., Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ag, Au, and Pb) can produce higher dark current. Doping elements (e.g., B, Al, Si, P, As, and Sn) can alter the operating characteristics of the devices. In SACHEM s quality control laboratory, ICP coupled to mass spectrometry is used to simultaneously analyze multiple trace elements in one sample in just 1 to 4 min. This ICP-MS instrument is a state-of-the-art instrument that can provide high throughput and low detection Emits at the parts per thousand level. Trace elemental determination at the parts per thousand level must be performed in a clean room so that trace elemental contamination from airborne particles can be minimized. 

In a search for sources of alkaline materials in rural air and rain, we have sampled and performed multi-element analyses on ambient particulate matter and potential source materials. Ambient aerosols were sampled daily using single Nuclepore filters or Florida State University "streakers." Samples of soil and unpaved road materials were also collected and analyzed. The samples were analyzed by various multi-element methods, including ion-and proton-induced X-ray emission and X-ray fluorescence, as well as by atomic absorption spectrophotometry. Visual observations, as well as airborne elemental concentration distributions with wind direction and elemental abundances in aerosols and source materials, suggested that soil and road dust both contribute to airborne Ca. Factor analysis was able to identify only a "crustal" source, but a simple mass balance suggested that roads are the major source of Ca in rural central Illinois in summer. 

The objective of this work was to identify calcium sources and their relative contributions in rural central Illinois as a step toward understanding the role of airborne alkaline... 

These results strongly indicate that roads are an important source of airborne alkaline materials in the summer, when the soil contribution is expected to be suppressed. 

Boekelheide, K. (1993) Sertoli cell toxicants. In Russell, L.D. Griswold, M.D., eds. The Sertoli Cell, Clearwater, FL, Cache River Press, pp. 551-575 Bove, J.L., Dalven, P. Kukreja, V.P (1978) Airborne di-butyl and di(2-ethylhexyl)phthalate at three New York City air sampling stations. Int. J. environ. Chem., 5, 189-194 Bradley, M.O. (1985) Measurement of DNA single-strand breaks by alkaline elution in rat hepatocytes. Prog. Mutat. Res., 5, 353-357... 

Chou H, Lin WL, Tam MF, Wang SR, Han SH, Shen HD Alkaline serine proteinase is a major allergen of Aspergillus flams, a prevalent airborne Aspergillus species in the Taipei Area. Int Arch Allergy Immunol 1999 119 282-290. 

Coccidioidomycosis is caused by infection with Coccidioides immi-tis, a dimorphic fungus found in the southwestern and western United States, as well as in parts of Mexico and South America. In North America, the endemic regions encompass the semiarid areas of the southwestern United States from California to Texas known as the Lower Sonoran Zone, where there is scant annual rainfall, hot summers, and sandy, alkaline soil. C. immitis grows in the soil as a mold, and mycelia proliferate during the rainy season. During the dry season, resistant arthroconidia form and become airborne when the soil is disturbed. 

Speciation of airborne chromium also has been investigated. Alkaline extraction of polycarbonate membrane filters was used to leach chromium which was subsequently determined by CFAAS. The National Institute of Standards and Technology has a standard reference material (SRM) 2584 - Trace Elements in Indoor Dust. Chromium in this SRM was successfully determined using high-resolution ICP-MS (Yu et al. 

There are no specific OSHA exposure standards for sodium or potassium silicate. Depending on rate of solution and degree of alkalinity of airborne materials, a prudent industrial exposure standard could range from the permissible expbsure limit (PEL) for inert or nuisance particulates up to nearly the PEL for sodium hydroxide. 

New fibers are being developed which dissolve in the slightly alkaline pH of the lung. These fibers may eventually replace the more common alumino-silicate fibers especially in use where human contact with breathable fibers is likely. Alumino-silicate fibers do not have the same small size as asbestos fibers, but the mere fact that they are fibers, could become airborne, and the body has no rejection mechanism, has prompted some countries to view them with suspicion. Having fibers which provide the same thermal properties but which would dissolved in the lung would preempt the possible problem. However, fibers which dissolve in alkaline conditions cannot be used with alkali stabilized colloidal silicas. They need a binder which is stable but acidic in pH as described above. Such products were first developed at DuPont and are now available through W.R. Grace who acquired the Ludox colloidal silica business from DuPont... 

Spectrophotometry There are numerous spectropho-tometric methods for the determination of cyanide including the pyridine-benzidine method, the pyridine-pyrazole method, and the pyridine-barbituric acid method. As an example, in the latter method the pyridine-barbituric acid coupling agent produces a complex with cyanide that adsorbs principally at a wavelength of 580 nm. This method is frequently used for the measurement of airborne hydrogen cyanide in industrial air. The hydrogen cyanide is collected in an alkaline bubbler, while any particulate cyanide is collected on a prefilter. With a 31 air sample the range of quantitation is about 0.3-235 ppm ( 3-260 mgm ). In water samples, this method has a lower limit of detection of about 0.02 mg 1 . ... 

Containment spray systems are used in some types of PWR plants, resulting not only in a condensation of steam but also in a washout of airborne radioiodine and other fission products from the containment atmosphere. Normtilly, an alkaline borate spray solution is used, resulting in a shift of the I2 disproportionation equilibrium to the iodate side and a suppression of revolatilization of iodine previously trapped by the spray droplets. In some cases, solutions containing sodium thiosulphate have been used to decompose volatile organic iodides present in the containment atmosphere, but because of its corrosivity this reagent has been largely abandoned. By the addition of boric acid to the spray solution, subcriticality of the reactor core is guaranteed when, after the injection phase, the sump water is recirculated for removal of decay heat from the core. 

The effectiveness of a spray system in removing fission product iodine from the containment atmosphere depends on several parameters, as is known from early investigations, among others those conducted by Row et al. (1969), by Patterson and Humphries (1969) and by Row (1971). Other experiments have demonstrated that spray solutions buffered at pH 9.5 are more effective in iodine removal by a factor of 3 than pure water, probably because acidification of the outer droplet layer is prevented which, in pure water, may be caused by the I2 hydrolysis and disproportionation reactions (Hyder, 1991). Other parameters controlling iodine removal by sprays are specific for the individual system under consideration (internal geometry, spray rate etc.). Spraying experiments performed in the context of the CSE tests (see Section 7.3.3.3.8.) showed a reduction of the airborne iodine concentration of more than one order of magnitude within a spray time of about 10 minutes subsequent spray periods were much less effective (Hilliard and Postma, 1981). In the case of airborne particulate iodide, the chemical composition of the spray solution (water, boric acid, alkaline borate solution) does not affect... 

The dust content of the atmosphere may have a wide variety of effects. Airborne ashes and soot usually contain water-soluble salts, especially sulfates, often sulfuric acid as well, and thus accelerate corrosion. On the other hand, alkaline dusts from the lime and cement industries may form hard incrustations and may thus sometimes have a protective effect. Mineral dusts like sand, e.g., during sandstorms in desert areas, may produce damage through abrasion or, by the mere formation of deposits, may inhibit the function of mechanical or electrical switching elements. 

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