Chromium particulate matter

Air (total chromium) Particulate matter collected on cellulose ester filter, digested with aqua regia ICP-AES 1 pg/m3 87-102% at 0.5-100 pg Lo and Arai 1988... 

A high-nickel alloy is used for increased strength at elevated temperature, and a chromium content in excess of 20% is desired for corrosion resistance. An optimum composition to satisfy the interaction of stress, temperature, and corrosion has not been developed. The rate of corrosion is directly related to alloy composition, stress level, and environment. The corrosive atmosphere contains chloride salts, vanadium, sulfides, and particulate matter. Other combustion products, such as NO, CO, CO2, also contribute to the corrosion mechanism. The atmosphere changes with the type of fuel used. Fuels, such as natural gas, diesel 2, naphtha, butane, propane, methane, and fossil fuels, will produce different combustion products that affect the corrosion mechanism in different ways. 

Air (total chromium) Air particulate matter collected on filter is cut out and irradiated with X-ray photons XRF 0.017 pg/m3 No data Wiersema et al. 1984... 

The production of coke by the carbonization of bituminous coal leads to the release of chemically complex emissions from coke ovens that include both gases and particulate matter of varying chemical composition. The chemical and physical properties of coke oven emissions vary depending on the constituents. The emissions include coal tar pitch volatiles (e.g., particulate polycyclic organic matter, polycyclic aromatic hydrocarbons, and polynuclear aromatic hydrocarbons), aromatic compounds (e.g., benzene and jS-naphthyl amine), trace metals (e.g., arsenic, beryllium, cadmium, chromium, lead, and nickel), and gases (e.g., nitric oxides and sulfur dioxide). 

During the 1987-1988 Antarctic Campaign, samples were collected and analyzed from twelve sites at Terra Nova Bay and along the Ross Sea shore. The concentrations of Cr, Cu, Fe and Ni in particulate matter were lower than those found in the Indian sector of the Southern Ocean obtained by a total attack (52). Chromium, Cu and Ni were not site-dependent the Fe concentration was higher... 

Yaghi B, Abdul-Wahab SA. Assessment of lead, zinc, copper, nickel and chromium in total suspended particulate matter from the workplace in Al-Rusayl Industrial Estate, Oman. J Environ Monit 2003 5 950-2. 

In 2003, urban air pollution was monitored at 76 stations (44 and 32 operated by the Ministry of Health and the Ministry of the Environment, respectively) located in 27 cities involved in the Monitoring System (SZU, 2004). In 2003, sulphur dioxide (SO2), nitrogen oxides (NO/N02/NOx), particulate matter (TSP and/or suspended PMio fractions), and mass concentrations of selected metals (arsenic, chromium, cadmium, manganese, nickel and lead) in particulate matter samples were monitored in all the cities of the Monitoring System except for Melnik. The SO2 measurements in the Public Health Service network were terminated at all the manual stations in the cities with CHMI stations in the cities without a CHMI station, measurements are made during the heating season only). Concentrations of carbon oxide, ozone, polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) continue to be monitored selectively in a number of the monitored cities. 

In the field of water analysis the interest is in differentiation between soluble and particulate chromium as well as between the two main oxidation states. The system Cr(III)/Cr(VI) is subject to redox reactions, especially in the presence of oxygen and/or organic materials. As soon as possible after its collection, water samples should be filtered if metal speciation is to be studied in order to avoid any remobilization of metals bound or sorbed to particulate matter. While pressure filtration offers advantages in terms of speed of filtration it may contribute to enhanced soluble organic matter by rupture of phytoplankton cells. 

The use of large-volume filter-based samplers for the collection of atmospheric particulates has also been combined with IC for the determination of absorbed metal species. Collected samples are extracted from the filters and desorbed from the particulate matter using acidic solutions prior to analysis by IC combined with elemental selective detection such as ICP-MS. Hexavalent chromium, platinum, and palladium have been determined in this way, as have many other transition and heavy metal ions. 

A significant health concern with particles, especially those from combustion sources, is their ability to carry toxic metals. Of these, lead is of the greatest concern because it usually comes closest to being at a toxic level. Problems with particulate lead in the atmosphere have been greatly reduced by the elimination of tetraethyl lead as a gasoline additive, an application that used to spew tons of lead into the atmosphere every day. Another heavy metal that causes considerable concern is mercury, which can enter the atmosphere bound to particles or as vapor-phase atomic mercury. Airborne mercury from coal combustion can become a serious water pollution problem, leading to unhealthy accumulations of this toxic element in some fish. Other metals that can cause health problems in particulate matter are beryllium, cadmium, chromium, vanadium, nickel, and arsenic (a metalloid). 

Some of the metals found predominantly as particulate matter in polluted atmospheres are known to be hazardous to human health. All of these except beryllium are so-called heavy metals. Lead is the toxic metal of greatest concern in the urban atmosphere because it comes closest to being present at a toxic level mercury ranks second. Others include beryllium, cadmium, chromium, vanadium, nickel, and arsenic (a metalloid). 

Iron and manganese occur in a number of soil minerals. Sodium and chlorine (as chloride) occur naturally in soil and are transported as atmospheric particulate matter from marine sprays (see Chapter 10). Some of the other micronutrients and trace elements are found in primary (unweathered) minerals that occur in soil. Boron is substituted isomorphically for Si in some micas and is present in tourmaline, a mineral with the formula NaMg3AlgB3Sig027(0H,F)4. Copper is isomorphically substituted for other elements in feldspars, amphiboles, olivines, p5Toxenes, and micas it also occurs as trace levels of copper sulfides in silicate minerals. Molybdenum occurs as molybdenite (M0S2). Vanadium is isomorphically substituted for Fe or A1 in oxides, pyroxenes, amphiboles, and micas. Zinc is present as the result of isomorphic substitution for Mg, Fe, and Mn in oxides, amphiboles, olivines, and pyroxenes and as trace zinc sulfide in silicates. Other trace elements that occur as specific minerals, sulfide inclusions, or by isomorphic substitution for other elements in minerals are chromium, cobalt, arsenic, selenium, nickel, lead, and cadmium. 

Wang, C.-F., Chin, C.-J., Luo, S.-K., and Men, L.-C. (1999). Determination of chromium in airborne particulate matter by high resolution and laser ablation inductively coupled plasma mass spectrometry. Anal. Chim.Acta 389(1), 257. 

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