Environmental material

IAEA (1985) [Muramai SU Y, Parr RM] Survey of currently available reference materials for use in connection with the determination of trace elements in biological and environmental materials. Report IAEA/RL/128, International Atomic Energy Agency, Vienna, Austria. 

Murad, E., Cashion, J. Mossbauer Spectroscopy of Environmental Materials and Their Industrial Utilization. Kluwer, Dordrecht (2004)... 

Directorate of Fisheries Research. 1990. Determination of alpha-emitting nuclides of plutonium, americium and curium in environmental materials Pt. 1. Seawater. Lowestoft, England Directorate of Fisheries Research. NTIS/DE92614732. 

A variety of strong acid dissolutions, e.g., 4-acid (near-total) extraction and aqua regia (total recoverable) extraction, are used by different agencies for the purpose of determining trace-element concentrations in environmental materials. 

Up to this point, the chemical reactivity hazards of individual substances, either by themselves or in contact with common environmental materials, have been considered. This last question in the chemical reactivity hazards screening will address the potential for an unintended chemical reaction due to incompatible materials contacting each other. Compatibility, in this context, means the ability of materials to exist in contact without specified (usually hazardous) consequences under a defined scenario. A scenario, in this context, is a detailed physical description of the process whereby a potential inadvertent combination of materials may occur (ASTM E 2012-00). 

The reliability of any environmental analytical data depends upon the reliability of sample quality. To generalize from analytical results on a small portion of material to a larger population requires careful planning and execution if bias is to be avoided. This article considers the general problems involved in sampling heterogeneous bulk populations such as soil, air, and natural waters specific details for particular types of materials are not included. These problems include the heterogeneity of most environmental materials the costs in time, manpower, and effort required for collection of real samples and the need to avoid contamination or decomposition of samples after collection. 

Tubrett, M., Mikova, J., Sylvester, P.J., Kosler, J. 2003. Trace element composition and homogeneity of MASS-1 sulfide oalibration standard In 5th International Conference on the Analysis of Geological and Environmental Materials, Rovaniemi. 9-11 June 2003... 

Analytical Methods for Determining Thorium in Environmental Materials... 

IDEMAT, Environmental Materials Database WWW. io. tudelft. nl/research/dfs/index. html... 

Several organizations (e.g., NIST, NRC-Canada, and IAEA) provide sediment reference materials containing radionuclides, many of which are only certified for artificial radionuclides ( Cs, Sr, Am, and Pu). Certain specific radionuclides have no certified natural matrix materials, including ocean, lake, and river sediments. Although these sediments are certified for a few naturally occurring and artificial radionuclides, the extent of radioactive equilibrium of the uranium and thorium decay series in these environmental materials is not provided. NIST currently offers an ocean sediment Standard Reference Material (SRM 4357) in... 

Fields of application in inorganic mass spectrometry Environmental materials... 

Media Definitions. Sample preparation media were defined by the participants to assist laboratories in selecting the appropriate protocol for a specific sample. These definitions were intended to encompass the continuum of wastes and environmental materials, to reduce overlap between individual medium definitions, and to reflect the scope of the protocols. The following media definitions were developed ... 

Touring the formation of radioactive fallout particles, one of the most important processes is the uptake, in the cooling nuclear fireball, of the vaporized radioactive fission products by particles of molten soil or other environmental materials. Owing to the differences in the chemical nature of the various radioactive elements, their rates of uptake vary, depending upon temperature, pressure, and substrate and vapor-phase composition. These varying rates of uptake, combined with different residence times of the substrate particles in the fireball, result in radiochemical fractionation of the fallout. This fractionation has a considerable effect on the final partition of radioactivity, exposure rate, and radionuclides between the ground surface and the atmosphere. 

Two substrate materials were used for most of the measurements. They were chosen as representative of two types of environmental material found in actual fallout. The first was a clay loam occurring in the Berkeley Hills, Calif. This is a more-or-less typical example of a silicate soil found in extensive areas in the temperate zones. The second material used was a calcium ferrite. This material has been observed in fallout resulting from nuclear explosions at the Pacific Proving Grounds where large amounts of calcium oxide, derived from the coral sand, and iron oxide, derived from towers, barges, or other structures, have been fused together. 

The radioactive particle population consists of environmental materials introduced into the fireball as pre-existing particles. These may be completely or partially melted, but if vaporized, they do not reappear as an identifiable part of the particle population. 

Analytical toxicology is a branch of analytical chemistry concerned with the identification and assay of toxic chemicals and their metabolites in biological and environmental materials. 

A related problem associated with efforts to characterize redox conditions of environmental materials is the lack of equilibrium among the chemical constituents of an environmental system (138-141) or between the environmental constituents and a sensor material (142). Thus, even techniques that are based on specific redox active species—such as H2 (143-146), Hg (147), indicator dyes (148, 149), or other mediators (137)— cannot provide a general characterization of redox conditions. However, we do recommend techniques that quantify the activity of specific oxidants or reductants, because they are necessary for the rigorous application of the approach Section 5.1 describes. Similar considerations apply to the characterization of redox kinetics. 

De Bortoli M, Gaglione P. 1972. Radium-226 in environmental materials and foods. Health Phys 22 43-48. 

We talk about adsorption when environmental materials are deposited on the surface of solids. Interface forces retain colliding molecules for a certain time. Possible causes include Van der Waals forces in the case of physical adsorption, chemical affinity (chemical sorption), or electrostatic forces. With polymers, we have to take into account all of these possibilities. 

In the case of solid environmental materials such as soils, sediments or indeed suspended particulates the use of selective chemical leaching methods can provide some basic information regarding the nature of the radionuclide species bound to the solid matrix. A typical sequential leaching might follow a procedure similar to that suggested for the study of trace metal binding to sediments by Gupta and Chen (1975) as shown in Fig. 13.2. 

The speciation of arsenic in environmental materials is of interest because of the differing levels of toxicity exhibited by the various species. The major arsenic species found in environmental and clinical samples are arsenite (As111), arsenate (Asv), dimethylarsinate (DMA), monomethylarsonate (MMA), arsenobetaine (AB) and arsenocholine (AC). Arsenite and arsenate are highly toxic, DMA and MMA are moderately toxic, whereas AB is virtually non-toxic. 

Investigations of lead speciation in various environmental samples have relied upon gas and liquid chromatographic separations coupled to mass spectrometric and atomic absorption spectrometric detectors. The combination of atomic absorption spectrometry with gas chromatography (GC-AAS) has proved to be the most widely applied technique. Sample types have included air, surface water, air particulates, sediments, grass, and clinical materials such as blood. A review of speciation analyses of organolead compounds by GC-AAS, with emphasis on environmental materials, was published (Lobinski et al., 1994). 

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