bluuebunny/crossref_metadata_2025 huggingface dataset:
Point‐of‐Care Testing
Authors: Kost Gerald J.
Published: September 2006

Point‐of‐care testing (POCT) is defined as testing at or near the site of patient care wherever that medical care is needed. The goal of POCT is to facilitate immediate evidence‐based medical decisions that improve patient outcomes and reduce patient acuity, criticality, morbidity, and mortality, especially during life‐threatening crises and emergency resuscitations. POCT is efficient and efficacious because it facilitates rapid diagnosis, faster treatment decisions, high‐quality trend monitoring, and patient and physician satisfaction. New point‐of‐care technologies are appearing rapidly. This article summarizes principles and analytical methods of whole‐blood analysis (WBA) for chemistry, hematology, and hemostasis analytes, cardiac injury markers, and other point‐of‐care diagnostic tests. Then, the article discusses important clinical aspects, including test clusters and medical indications, methods of monitoring and enhancing performance, and optimization strategies. In the next two decades, diagnostic testing will continue to shift to the point of care, necessitating collaborative integration, information consolidation, and Knowledge Optimization®in surgery, intensive care, emergency medicine, and other settings extending from the acute care center to the patient's home.
Product Development for the Clinical Laboratory
Authors: Krouwer Jan S.
Published: September 2006

Clinical assays have an important role in medical decision making. Test results help a clinician answer a fundamental question, “how should I treat the patient?” Whereas these assays used to be developed in hospital laboratories and were performed by skilled technicians, the availability of automated instruments has created an industry which now provides most of the assays. The industry is highly competitive – development of assay systems requires a product development process that is efficient. Most companies use a development process that breaks product development into stages: (1) researching new opportunities, (2) proving feasibility, (3) scheduled development, (4) validation, and (5) product launch. Each stage has methods and tools that help attain the commercial goal.
Serum Proteins
Authors: Ritchie Robert F. , Whicher John T.
Published: September 2006

Plasma contains a large number of different proteins with varying structural characteristics. The “plasma proteins” have been defined on the basis of plasma concentration and amenability to measurement in certain types of measurement systems. In the past, they were proteins present with concentrations above 0.05 g L
−1
, but more recently detection limits have been decreased to about 0.001 g L
−1
. However, the group of proteins is not defined on a pathophysiological basis and the definition remains idiosyncratic and incomprehensible to the noncognoscenti. The function of an increasing proportion of them is known and the evidence suggests that they are present either with a specific role in the plasma or that they represent cellular proteins shed into the circulation as a result of degradative processes. Many plasma proteins show characteristic changes in concentration or structure either resulting from genetic dictates that may give rise to disease directly or as a result of changes reflecting pathological or physiological processes. All the transcellular fluids, such as cerebrospinal fluid (CSF), urine, synovial fluid and saliva, contain most or all of the plasma proteins, but there are some additional proteins secreted specifically into these fluids.

This chapter reviews the many methods applied to proteins for clinical and research purposes. Also addressed are the pitfalls not often appreciated by the worker presented with a sample to be analyzed in an increasingly impenetrable “machine”.
Statistical Quality Control in Clinical Laboratories
Authors: Dechert Jerry
Published: September 2006

The importance of reporting quality patient results by clinical laboratories cannot be overstated. Maintaining and improving the quality of laboratory results is a never‐ending process, and the thoughtful application of statistical quality control techniques is the key to this continuous pursuit. Using statistical methods, laboratories can ensure that their patient results are reliable and can continue to improve their performance.

It is clear that the method for monitoring quality control in the clinical laboratory will have a direct impact on the results reported by the laboratory. This article reviews the historical development of clinical quality control and details methods traditionally applied in the field. Recently proposed approaches are identified and their statistical performance is evaluated. Quality control methods involving clinical significance are also described, and economic modeling applicable to clinical quality control is presented.
Supercritical Fluid Chromatography in Clinical Chemistry
Authors: Graves Steven W.
Published: September 2006

Supercritical fluid chromatography (SFC) employs a gas taken above its critical temperature and critical pressure to where it forms a supercritical fluid (SF). SFs have properties of both gases and liquids. They have lower densities and viscosities and higher diffusion coefficients than liquids, but they also have the solvating power of a liquid and can dissolve nonpolar and many polar compounds. As such, these favorable properties combine to make SFs an excellent mobile phase for column chromatography. The SFC technique is highly versatile in that it can be used with either packed columns (similar to high‐performance liquid chromatography (HPLC) columns with the same variety of stationary phases available) or open‐tubular columns (similar to gas chromatography (GC) columns and employing the same types of coatings) which can be interfaced with a very wide array of detectors. In addition, SFC avoids high temperatures during the chromatographic separation and in most cases the need to derivatize analyzed compounds. These features make SFC particularly well suited to the separation and assay of clinically important biomolecules. As SFC instruments have become commercially available, numerous applications have been explored in the areas of drug monitoring, toxicology, environmental contaminants, and the measurement of physiological biomolecules. Despite its potential, SFC enjoys limited use in clinical chemistry laboratories currently. Greater efforts are needed to improve sensitivity, standardize and validate assays, and work toward high‐volume throughput capabilities.
Atomic Spectrometry in Clinical Chemistry
Authors: Parsons Patrick J.
Published: September 2006

Atomic absorption spectrometry (AAS) and atomic emission spectrometry (AES) are two closely related instrumental techniques that have many applications in many different fields. In clinical chemistry, these techniques are well established for the quantitative measurement of essential and nonessential elements found in body tissues and fluids. For most practical purposes, the elements that are routinely measured with modern commercial instrumentation include almost all of the metallic elements of the s, d and p blocks of the periodic table. The exceptions in the p block include the halogens, the noble gases and the elements C, H, N, O and S. Above atomic number 83 (Bi), only U is measured in absorption. With the emergence of commercial instrumentation for atomic mass spectrometry, e.g. inductively coupled plasma mass spectrometry (ICPMS) clinical chemists have another powerful tool with which to measure multielement composition of biological specimens at ultratrace concentrations, i.e. <10 µg L−1. With ICPMS, the halogens become detectable, along with B, C, N and Th. The coupling of ICPMS with separation technologies has opened new possibilities in clinical laboratory medicine in the field of speciation.

In some areas of clinical chemistry, older atomic spectroscopy techniques are still considered the reference method for selected clinical applications, e.g. the determination of serum K and serum Na by flame atomic emission spectrometry (FAES). In other areas, flame atomic absorption spectrometry (FAAS) remains the method of choice for serum Mg and serum Cu because of its sensitivity, rapid throughput and the relatively low cost of instrumentation. Electrothermal atomic absorption spectrometry (ETAAS), while more complex than flame atomization methods, is the method of choice for applications such as blood Pb, serum Al and serum Se, where physiological concentrations are too low to be measured in the flame without laborious preconcentration efforts. Robust procedures for quality assurance (QA) and quality control (QC) are now well established within the clinical laboratory and cover the entire spectrum of clinical laboratory activities. These include preanalytical issues, personnel training and education, and also the appropriate use of certified reference materials (CRMs) for method validation purposes. Participation in proficiency testing (PT) programs and external quality assessment schemes (EQAS) for trace elements in biological fluids have also contributed to improved clinical laboratory performance. Despite the advent of ever more sensitive techniques and robust procedures, the quality of results is still only as good as the specimen collected. Contamination can occur at the preanalytical stage of the analysis and also during the analysis. Selection of the appropriate specimen is critical to obtaining meaningful clinical information about nutritional trace element status or exposure to toxic elements.
Ultraviolet/Visible Light Absorption Spectrophotometry in Clinical Chemistry
Authors: Upstone Stephen L.
Published: September 2006

Ultraviolet/visible (UV/VIS) absorption spectroscopy has been used in the clinical laboratory for many years. The technique has appeal, as it is almost universal in its application. Although much of the routine work is performed using high‐throughput dedicated clinical analysis systems, absorption spectroscopy still has a place in most clinical laboratories.

This article discusses the range of application types for which absorption spectroscopy can be used and some examples of common analyses are given. The article also discusses the merits of various instrument types and discusses some more advanced spectroscopic techniques, such as derivative spectroscopy, to enhance the data measured by the spectrophotometer. Brief reference is also made to the use of reflectance in clinical analysis.
Nuclear Magnetic Resonance of Coating and Adhesive Systems
Authors: Brandolini Anita J.
Published: September 2006

The interaction of the magnetic moment of an atomic nucleus with a static magnetic field gives rise to nuclear magnetic resonance (NMR). Examination of NMR can reveal both the chemical structure and physical characteristics of a chemical system and this makes the technique particularly useful for the study of materials such as those encountered in coating and adhesive applications. No other spectroscopic technique can offer such a detailed description, both qualitative and quantitative, of molecular structure, including features such as stereochemistry, reaction kinetics and surface phenomena. Each nucleus has a distinct precession frequency, allowing different (e.g.
13
C,
1
H,
29
Si) to be observed within a sample. The technique does, however, suffer from a few drawbacks. First, it is not a particularly sensitive technique, and it is most readily applied to features that constitute at least a few percent of the sample. Second, sample preparation can be difficult; this can be especially true for coatings and adhesives materials, as will be discussed. The most detailed chemical information is obtained from the spectra of liquids or solutions, which precludes cross‐linked or cured materials. The spectra of solids, including cross‐linked and cured materials, must be studied using complex experimental approaches, and these often suffer from poor resolution.
Rheology in Coatings, Principles and Methods*Portions of this article are excerpted, by permission, from the chapter ‘Rheology and Viscometry’ by R.R. Eley, in the
Paint and Coatings Testing Manual: 14th Edition of the Gardner‐Sward Handbook
(1995), ASTM, 100 Bar Harbor Drive, West Coshocken, PA 19429‐2959.
Authors: Eley Richard R.
Published: September 2006

Rheology by definition is the study of the deformation and flow behavior of materials. An operational definition would be “the study of the response of certain materials to the stresses imposed on them”. Rheology seeks to understand the relationship between applied force, or stress, and the resulting deformation, particularly for materials showing nonsimple responses. Such a relationship expressed mathematically is termed a constitutive equation. Perhaps the most familiar such equation is Hooke's law for elastic solids, which states the linear relationship between the stress σ and the deformation or strain γ [Equation 1]:

where the modulus G is the constant of proportionality. However, rheology is primarily concerned not with the solid state but with the study of fluid behavior, and the simplest constitutive relation for a liquid is Newton's law [Equation 2]:

where the coefficient of viscosity or, more commonly, the viscosity η expresses the proportionality between stress and, now, not strain but the strain rate,

$\dot{\gamma}$

.

For the ideal, simple materials described above, G and η are called material constants because they are dependent only on the thermodynamic variables of temperature, pressure, and concentration, similar to a material property such as the density. However, rheology is not concerned with either Hookean solids or Newtonian liquids. It is rather concerned with materials whose constitutive relationships involve complex behavior. For such materials, G and η are no longer material constants but material functions. Their values will now depend on variables such as the magnitude of applied stress, strain, strain rate, and even the deformation history. In fact, for rheologically interesting materials, the behavior is somewhere between that of a Newtonian liquid and an elastic solid. Such materials are termed non‐Newtonian, and may display time‐dependent, plastic and viscoelastic behaviors.

Paints and industrial coatings, creams and lotions, inks, adhesives, ceramic slips, solder pastes, foods, medicines, etc. are representative of the range of materials whose commercial viability depends on having the correct rheology for the application. In turn, the required rheological properties must be defined with reference to the specific process at hand. This article introduces the science of rheology, with description of basic terms, models, and methods used. The mechanisms responsible for complex rheological behavior and the use of rheological measurements to understand and control the flow of materials are described. The emphasis is on coatings and coatings processes as points of reference, but the principles discussed apply to a wide range of materials and industrial products.
Automotive Emissions Analysis with Spectroscopic Techniques
Authors: Hirschberger Rainer
Published: September 2006

Quantitative analysis of automotive emissions gives detailed information about a motor's combustion behavior and gives information about the contribution from traffic to air pollution. Following the introduction, which discusses the problems of exhaust gas analysis, section 2 covers the basics of the physical effects, that the different spectroscopic systems are based on. These physical effects are discussed especially with respect to gas analysis.

Section 3 describes the functioning of different spectroscopic systems, the measuring procedures and different examples of exhaust gas analysis. Simple examples are used to illustrate the functioning of Fourier transform infrared (FTIR) and diode laser (DL) systems. The construction of a completely home‐made Raman polychromator is described in detail. Specific problem areas are pointed out. Selected examples of exhaust gas analysis show typical applications of the particular methods.

Section 4 discusses the present and future potential of the systems described.
Optical Gas Sensors in Analytical Chemistry: Applications, Trends and General Comments
Authors: Rathgeb F. , Gauglitz G.
Published: September 2006

Current concepts for optical gas sensors are reviewed. Different approaches for gas sensing such as intrinsic and extrinsic, direct and indirect sensing were taken into consideration. For each sensing approach reviewed here, a short principle description and recent applications are given. Several aspects governing the enrichment of gaseous analytes in sensitive layers are also discussed briefly.
Fourier Transform Infrared Spectrometry in Atmospheric and Trace Gas Analysis
Authors: Griffith David W.T. , Jamie Ian M.
Published: September 2006

Fourier transform infrared (FTIR) spectrometry is the dominant technique used to measure the infrared (IR) absorption and emission spectra of most materials, with substantial advantages in signal‐to‐noise ratio (S/N), resolution, speed and detection limits over conventional dispersive spectroscopy. In this application, FTIR spectrometry is used to measure the trace gas composition of the atmosphere. Applications to both clean and polluted air are described. Techniques include measurements over open paths in situ, sampling and measurement in closed cells in the field or laboratory and, briefly, remote sensing using the sun, sky or natural hot objects as an IR radiation source. The techniques are applicable to a very wide range of compounds, including labile or reactive species, and all species are measured simultaneously. Detection limits vary with the application but are typically of the order of parts per billion (nmol mol−1) in air.
Laser Absorption Spectroscopy, Air Monitoring by Tunable Mid‐Infrared Diode
Authors: Tacke M. , Wienhold F. , Grisar R. , Fischer H. , Lübken F.‐J.
Published: September 2006

Infrared (IR) spectroscopy is a proven tool for gas analysis, and tunable mid‐IR diode laser absorption spectroscopy is a special technique giving optimum sensitivity, selectivity and measurement speed for most molecules of interest. Molecules such as the NO
x
family (N
2
O, NO, NO
2
, HONO, and HNO
3
) can be detected selectively down to well below part per billion levels. The technique works well with all molecules having line spectra and thus is quite universal. It is conceptually simple and detects gases by repetitively scanning absorption lines, which is possible due to the narrow laser line width and easy laser tuning. The scanning procedures of diode laser spectroscopy optimally reduce background fluctuations. Basic operation principles are explained in the article.

Alternative techniques are well established and often allow detection of single components at lower system cost, but in general need specific sample pretreatment that makes the results often difficult to compare. Mass spectroscopy is an alternative multicomponent technique that reaches comparable selectivity, but only with preselection processes which induce calibration problems of their own, such as matrix‐dependent sensitivity. In order to give an insight into the capabilities of tunable mid‐IR diode laser absorption spectroscopy, three exemplary systems are treated in detail for air monitoring from airplanes, from rockets, and gas analysis of combustion exhaust. System parameters are explained, and system performance is compared with alternative techniques.
Laser‐ and Optical‐Based Techniques for the Detection of Explosives
Authors: Monts David L. , Singh Jagdish P. , Boudreaux Gary M.
Published: September 2006

A wide variety of optical‐ and laser‐based techniques have been and are currently being investigated as means of identifying and characterizing explosive materials. These efforts are hampered by the very low volatility of explosive compounds at room temperature and their tendency to ignite at higher temperatures where their vapor pressures are beginning to reach a regime where the species can be readily detected. Traditional, condensed‐phase absorption spectroscopy (both infrared (IR) and ultraviolet/visible (UV/VIS)) requires larger samples than are frequently available and, although useful as confirmatory techniques, do not provide signatures that enable unique identification of species. The choice of nontraditional techniques for analysis of explosive materials is dependent upon the amount of sample available, the sample matrix, and sample‐imposed constraints upon the measurement. Raman spectroscopy can identify and quantify condensed‐phase explosive materials, but the detection limit depends upon substrate, excitation wavelength, and illumination area: limits of detection (LODs) vary from 0.05 ng for 2,4,6‐trinitrotoluene (TNT) on glass to 10 µg for nitroglycerin (NG) on silica gel. The other detection techniques considered require volatilization of either the explosive compound itself or more often of characteristic decomposition products, such as NO, NO2, or N2O. Using IR irradiation, researchers have demonstrated that photoacoustic spectroscopy (PAS) has detection limits ranging from 0.55 ppb (parts per billion) for vapor‐phase NG with 9 µm excitation to 220 ppm (parts per million) for vapor‐phase 2,4‐dinitrotoluene (DNT) with 6‐µm excitation. IR laser differential absorption detection of dissociation products NO, NO2, and/or N2O can achieve detection limits of a few picograms. Laser‐induced fluorescence (LIF) detection of the photofragments (typically NO) of explosive compounds yields detection limits in the tens to hundreds of ppb (by weight) range. Low LODs can be achieved using ion detection techniques: resonance‐enhanced multiphoton ionization (REMPI) spectrometry is capable of LODs for detecting vapor‐phase explosives compounds in the hundredths to tens of ppb range; ion mobility spectrometry (IMS) has vapor‐phase detection limits for common explosive compounds of typically 200 pg, but for some species can be significantly lower: for example, 1 pg for TNT.
Photoacoustic Spectroscopy in Trace Gas Monitoring
Authors: Harren Frans J.M. , Cotti Gina , Oomens Jos , Hekkert Sacco te Lintel
Published: September 2006

Since ancient times people have searched for ways to understand processes occurring in the environment, atmosphere or living organisms. Study of the gaseous trace compounds present may shed new light on chemical reactions taking place in the atmosphere or biochemical reactions inside organisms such as plants, animals and human beings. This article presents photoacoustic spectroscopy as a sensitive, on‐line and noninvasive tool for monitoring the concentration of trace gases. Following a short introduction and a historic overview, attention is focused on the description of devices and equipment which determine the detection limits and selectivity. An overview is given of the current detection limits for photoacoustic detection. Applications are discussed with emphasis on environmental monitoring (in ambient air, car exhaust and stack gas emission), on medical applications and on biological applications (in postharvest physiology, plant physiology, microbiology and entomology).
Asbestos Analysis
Authors: Höfert Norbert , König Reiner
Published: September 2006

The comprehensive use of asbestos in approximately 3000 industrial applications in the past requires asbestos analysis at present and in the future. The different analysis methods range from simple and cost‐effective procedures in order to decide whether asbestos is present up to the expensive and time‐consuming determination of low fiber number concentrations of asbestos fibers including the identification of the fiber type using highly sophisticated measurement equipment.

The following survey discusses the most relevant objectives of asbestos analysis and the measurement techniques that are applied:

Ambient/indoor air measurements – low concentration range, fiber type usually not known, identification required – using transmission electron microscopy (TEM) in combination with energy‐dispersive X‐ray analysis (EDXA) and selected area electron diffraction (SAED), and using scanning electron microscopy (SEM) in combination with EDXA.

Workplace air measurements – low to high concentration range, fiber type usually known, identification possibly required – using SEM, TEM, and phase contrast optical microscopy (PCOM).

Stationary source emission measurements using SEM, TEM, and PCOM.

Bulk material analysis – usually qualitative measurements; semiquantitative or quantitative results possible, if required – using SEM, TEM, infrared (IR) spectroscopy, PCOM, polarized light microscopy (PLM), and X‐ray diffraction (XRD).

Water analysis using TEM.
Atomic Fluorescence in Environmental Analysis
Authors: Cai Yong
Published: September 2006

Atomic fluorescence is a spectroscopic process which is based upon the absorption of radiation of a certain wavelength by an atomic vapor and subsequent radiational deactivation of the excited atoms toward the detection device. Both the absorption and the subsequent atomic emission processes occur at wavelengths which are characteristic of the atomic species present. Atomic fluorescence spectroscopy (AFS) is a very sensitive and selective method for the determination of a number of environmentally and biomedically important elements such as mercury, arsenic, selenium, bismuth, antimony, tellurium, lead, and cadmium. This technique has become one of the most important analytical tools for trace element analysis in environmental samples, such as mercury, owing to its advantages over other methods in terms of linearity and detection levels. Several books and a number of book chapters and review articles have been published dealing with the theory and instrumentation of AFS. This article will provide up‐to‐date AFS information regarding its application in environmental analysis.
Cyanogen Chloride and Cyanogen Bromide Analysis in Drinking Water
Authors: Xie Yuefeng , Hwang Cordelia J.
Published: September 2006

Cyanogen chloride (CNCl) (CAS
506‐77‐4
) is a common disinfection by‐product DBP formed in chloraminated waters. Cyanogen bromide (CNBr) (CAS
506‐68‐3
), the brominated analog of CNCl, is formed in chloraminated or ozonated waters that are high in bromide. Both CNCl and CNBr are labile in drinking water. They undergo degradation reactions at high pHs or in the presence of free chlorine or sulfite. Because of its potential health effects, CNCl was included in the United States Environmental Protection Agency (USEPA) Information Collection Rule (ICR). Aqueous standards for CNCl are generally prepared with pure CNCl gas. They can also be prepared with chlorinated or chloraminated cyanide (CN
−
) solutions. Aqueous standards for CNBr are prepared with commercially available CNBr. For sample preservation, ascorbic acid is commonly used to quench the residual chlorine or chloramines. Acid is often added to lower the pH to prevent possible hydrolysis degradation. There are three methods for analyzing CNCl and CNBr in drinking water samples: purge‐and‐trap gas chromatography/mass spectrometry (PT GC/MS), headspace gas chromatography/electron‐capture detection (GC/ECD), and micro liquid–liquid extraction gas chromatography/electron‐capture detection (LLE GC/ECD). All three methods are capable of analyzing microgram per liter levels of CNCl and CNBr in drinking water, and all three give similar method performance, including accuracy, precision, spiking recovery, and method detection limit. The PT GC/MS method is a modification of the USEPA Method 524.2, which requires the use of specialized instrumentation. Because of CNBr's low vapor pressure and high water solubility, the analysis of CNBr also requires a heated purge. Headspace GC/ECD method is a relatively simple and rapid analytical method. As the samples are prepared individually, the method requires a full‐time analyst to prepare and inject each sample. However, this analytical procedure can be automated using a commercially available headspace autosampler. In general, micro LLE GC/ECD is a well developed and common procedure for DBP analysis. The micro LLE GC/ECD method, originally developed for CNBr analysis, has been further developed for both CNCl and CNBr analysis in drinking water. The sample injection generally is automated with a common gas chromatography (GC) autosampler.
Explosives Analysis in the Environment
Authors: Tomkins Bruce A.
Published: September 2006

The interest in analytical procedures for explosives residues in environmental media steadily increases as more and more formerly utilized military sites are certified and converted to full‐ or part‐time civilian use. Careful statistical studies have clearly demonstrated that analyses based on randomly collected “grab” samples of soils frequently produce a false picture of the extent of explosives contamination. Well‐designed sampling plans, which employ multiple samples taken from small areas and which consider the distribution of the soil particles, are mandatory for understanding the true extent of contamination. Because site remediation is such a costly venture, there is a strong need for analytical procedures which are capable of quantitating explosives in soil and groundwater samples quickly and accurately, using equipment and methods which may be operated reliably by nontechnical personnel. For that reason, scientific interest is gradually moving away from the completely laboratory‐based, statistically validated, and highly technical standardized methods, such as high‐pressure liquid chromatography (HPLC) and gas chromatography (GC) and their mass spectroscopic analogs, towards the many fieldable analytical techniques. Some of these, such as ion mobility spectrometry and the various magnetic resonance techniques, are still in their infancy; their potential and utility are still to be fully developed. Others, such as the colorimetric and enzyme‐based field test kits, have been fully tested and, in some cases, have been adopted as standard methods themselves. Still others, such as the various mass spectrometric methods, involve highly technical equipment which must be simplified before it can be used routinely in the field. However, the extreme sensitivities characteristic of these state‐of‐the‐art instruments partially offset the need for extensive operator training. A variety of mass spectrometric techniques may yet be used routinely for explosives residue analysis in the field. Some of these new methods may be used in, or even be derived from, forensic applications.
Formaldehyde, Environmental Analysis of
Authors: Srivastava S.S. , Maharaj Kumari K.
Published: September 2006

Formaldehyde is a ubiquitous component of both the remote atmosphere and polluted urban atmospheres. Interest in ambient concentrations of formaldehyde derives both from concerns over health effects and from the primary role that formaldehyde plays in the tropospheric chemistry cycle. It is an important intermediate product occurring in all regions of the atmosphere, and arises from the oxidation of methane and other biogenic and anthropogenic hydrocarbons. In spite of the increasing interest in the levels and fate of formaldehyde in the environment, there is at present no simple method available for the determination of trace amounts (i.e. nanograms) of carbonyls in air, water, and other environmental samples. This article reviews all the available methods (qualitative and quantitative) for the analysis of formaldehyde in various matrices, including sampling of atmospheric formaldehyde. The various methods discussed include colorimetric, titrimetric, polarographic, and chromatographic methods. Fourier transform infrared spectroscopy (FTIR) and tunable diode laser absorption spectroscopy (TDLAS) have been reviewed, and fluorimetric methods of analysis have also been dealt with. The article includes a comparison of the various methods with respect to sensitivity, detection limits and interference.
Gas Chromatography by Direct Aqueous Injection in Environmental Analysis
Authors: Biziuk Marek
Published: September 2006

Sample pretreatment, the initial stages of an analytical procedure, becomes the essential stage in environmental analysis. The only method of determination of organic compounds in water which avoids the isolation and preconcentration step uses direct injection of an aqueous sample on to a gas chromatographic column. Direct aqueous injection (DAI) is the simplest method for the determination of organic water pollutants. This method is also very fast and easy to automate. The method avoids the problems associated with using solvents (toxic and expensive) and incomplete recovery of the analytes during their isolation from the aqueous phase, the effect of potential contaminants when using solvent or solid‐phase extraction (SPE), and losses of the analytes during the enrichment step.

The idea of DAI on to a chromatographic column is very old and for liquid chromatography and ion chromatography was widely applied from the beginning of these techniques. In the beginning of the application of this technique in gas chromatography (GC), packed columns were used. The real issue for the development of GC and the application of DAI is connected with introducing to practical use a capillary column with a polar or non‐polar stationary thin liquid film or thin layer. The next, very important step was to introduce a direct injection on‐column, which eliminates a lot of problems connected with injection in the split or splitless mode.

The determination of haloforms in water using DAI on to a capillary column and electron capture detection (ECD) was the most spectacular application of this method. The DAI/GC/ECD method was used for determination of haloorganic compounds in the different aqueous samples (tap, surface, swimming pool, and seawaters, beers, juices, soft drinks, and physiological liquids). This method was also used for the determination of semivolatile and nonvolatile haloorganic and other organic compounds in the different aqueous samples.
Gas Chromatography with Atomic Emission Detection in Environmental Analysis
Authors: Pedersen‐Bjergaard Stig
Published: September 2006

When capillary gas chromatography (GC) is coupled with atomic emission detection (AED), mixtures of volatile and semivolatile organic compounds are first separated based on different retention in a capillary GC column, whereafter the separated compounds are introduced directly into a helium (or argon) plasma. The high temperature of this plasma results in atomization of the separated compounds followed by excitation of the constituent atoms. From the excited states, the atoms emit light of characteristic wavelengths which are monitored continuously during the chromatographic separation by an optical spectrometer. This results in element‐selective chromatograms, where all elements from the periodic table (except helium or argon) may be monitored selectively with a simple change of wavelength on the spectrometer. With the use of multichannel spectrometers, several elements may be monitored simultaneously resulting in multielemental detection. Both nonmetallic and metallic elements are detected with a very high selectivity. This enables environmental contaminants containing heteroatoms to be determined in dirty extracts without extensive sample cleanup. However, since detection limits (DLs) in GC/AED range from 1–100 pg s
−1
, extensive analyte enrichment is often required prior to environmental analysis. Because the separated compounds are atomized within the plasma, only minor structural variations are observed for the detector responses. This, in combination with the multielemental capability, enables estimation of empirical formulas for each of the separated compounds, which may be utilized to support identification of environmental micropollutants. In addition, the structure‐independent detector responses enable simplified calibration for quantitative purposes because different compounds may be quantified based on a single elemental calibration curve.
Gas Chromatography with Selective Detectors for Amines
Authors: Kataoka Hiroyuki
Published: September 2006

The presence, identity and quantity of amines in the environment should be established to evaluate possible health hazards. In many cases, environmental amines are present at very low concentration and are often found among a myriad of other compounds from which they must be separated and identified. Therefore, analytical methodology for the isolation and quantification of these amines needs selective and sensitive detection. The present article is concerned with the utilization of selective gas chromatographic detectors for amine analysis and their application to the determination of amines in environmental samples.
Immunoassay Techniques in Environmental Analyses
Authors: Lesnik Barry
Published: September 2006

In the 1980s, several Program Offices of the United States Environmental Protection Agency (USEPA) investigated the use of immunoassay methods for environmental applications with limited success. Most of the problems were with method ruggedness, i.e. they worked well in clean spiked matrices, but not very well on real world samples. The situation changed significantly in January of 1992, when the Office of Solid Waste (OSW) received its first rugged immunoassay method (for pentachlorophenol (PCP)) that worked on field samples. Several more followed, and through the early and mid‐1990s, the USEPA initiated use of immunoassay methodology in its hazardous waste program. The first group of methods incorporated into the OSW's methods compendium, Test Methods for Evaluating Solid Waste, or SW‐846, between 1993 and 1995 were a group of 10 enzyme‐linked immunosorbent assay (ELISA)‐based screening methods for various environmental analyte classes. These methods were officially ‘approved’ by the USEPA in July, 1997. We provided a great deal of training on these methods to raise the comfort level of the environmental community for their use.

This chapter addresses several major topics including an overview of the USEPA's major Regulatory Programs; how analytical methods are used in Regulatory Programs; general guidelines for the development of screening methods; specific validation criteria for immunoassay methods; the current status of the USEPA immunoassay method development program; current and potential environmental applications for immunoassay technology; barriers to implementation of immunoassay methods and the steps being taken to overcome them; and future directions and new developments in immunoassay technology for regulatory programs.

The overall future of the technology for environmental monitoring and analysis looks very bright. It offers a cost effective way to generate reliable information upon which to base sound environmental decisions.
Inductively Coupled Plasma Mass Spectrometry in Environmental Analysis
Authors: Yamasaki Shin‐ichi
Published: September 2006

The first sections of this article describe a brief history, the basic principles and advantages as well as disadvantages of inductively coupled plasma mass spectrometry (ICPMS) over other analytical techniques commonly used for environmental analysis (see Figure 1). Section 4 is devoted to the discussion of the relative merits and demerits of a wide variety of dissolution techniques and their limitation in the pretreatment of various environmental samples. In section 5, efforts are concentrated on the novel application of ICPMS to such typical environmental samples as water, soil, and biological materials. In the last sections of the article, future perspectives of new ICPMS and related devices are discussed. The topics chosen are high resolution ICPMS, multiple‐collector instruments, time‐of‐flight (TOF) ICPMS, collision cell interface ICPMS, and low‐sample consumption nebulizers.
Industrial Waste Dumps, Sampling and Analysis
Authors: Rasemann Winfried
Published: September 2006

Industrial sites where residues and wastes such as slags, ashes, dust and sludges have been dumped are essential parts of the environment and of the economic structure. The amount of waste produced, distributed and deposited is constantly increasing. The wastes can contain hazardous components that pollute and endanger the environment, but they can also consist of valuable materials, which are a source of secondary raw materials. To assess the environmental risk caused by the waste, or to calculate the economic benefit of dumped material, a reliable knowledge of the waste composition is required. Waste management experience has regularly shown that conflicts and lawsuits are the result if the composition of the waste materials is difficult to determine reliably. Investigations carried out by different institutions and persons, or by the same personnel under varying conditions, will often have very different results. The measuring technology and the measuring methods cannot be the only reasons for that. Nowadays, it is possible to accurately determine chemical components in any natural concentration, and there is no problem in distinguishing the size and shape of particles down to the nanometer scale. The problems are created because the wastes are mixtures of particles and lumps which vary in size and shape as well as in chemical composition and physical properties. A waste dump with a varied production history and dumping conditions, with chemical reactions or physical changes occurring after dumping, will be heterogeneous as a rule. Therefore, the evaluation of any dump of industrial waste materials is quite difficult. To ensure that the results of evaluation are comparable, certain regulations of investigation must be followed. According to the delivery, the wastes are classified into material streams (stationary, moving or free falling), heaps delivered within containers and vehicles, and free‐standing heaps. As it is economically unjustifiable to investigate the entire waste dump, subsets of material (called samples) must be taken from the stream, the container or the heap in order to determine the measurements of interest. In doing this, rather a lot of errors can be made. Therefore, the errors that exist are frequently caused by unobjective sampling and improper handling of the sample material. However, a false estimation can also be made by evaluating reliable data using unsuitable statistical methods.

The present contribution takes up this problem. An industrial waste dump and a contaminated site were chosen as examples, and proven sampling regulations were applied. The applicability of known statistical and geostatistical methods developed for homogeneous granular bulk solids and uniformly contaminated soils to the evaluation of extremely heterogeneous waste dumps and nonuniformly contaminated industrial sites is shown.
Inorganic Environmental Analysis by Electrochemical Methods
Authors: Somer Güler
Published: September 2006

After the industrial revolution considerable emphasis was placed on monitoring organic, inorganic and organometallic substances in the environment. Environmental contaminants include products of combustion, vapors, gases, industrial solvents, dusts, agricultural fertilizers, pesticides, radioisotopes, noise, ultraviolet light and certain microwave electromagnetic radiations.

Contaminants that are present in strong enough concentrations to pose an immediate threat to life or to cause unmistakable cases of disease or acute poisoning are usually readily apparent, and experience has led to the development of adequate, but by no means perfect, environmental control measures. The effects of environmental contaminants are related to time as well as concentration or intensity. Time factors become increasingly important when low concentrations of contaminants do not produce ill effects until after months or years of exposure. Trace analytical methods, therefore, play a very important role in environmental analyses. They are required for the detection and identification of chemical pollutants present in the environment. It is essential that the analytical methods applied are suitable and that they yield reliable data. These methods have to have high sensitivity, as many toxic chemicals are present in environmental samples at microgram per liter levels. Furthermore they have to cover a large dynamic range, and most important they have to be inexpensive. Voltammetry fulfills all of these features and it can be used both in trace metal analyses and in the determination of organic compounds in environmental samples. This article will cover the determination of inorganic pollutants in air, water and soil, using electrochemical (EC) methods.
Ion Chromatography in Environmental Analysis
Authors: Jackson Peter E.
Published: September 2006

Ion chromatography (IC) is a subset of liquid chromatography applied to the determination of ionic solutes, such as inorganic anions, cations, transition metals, and low‐molecular‐weight organic acids and bases. Although these solutes can be analyzed using a number of separation and detection modes, ion‐exchange is the primary separation mode and suppressed conductivity is the primary method of detection in IC. Method detection limits (MDLs) for inorganic anions and cations are typically in the low parts per billion range and recoveries obtained for ions in spiked water samples are generally in the order of 80–110%. The linear calibration range extends from low parts per billion to mid parts per million concentrations for most applications. IC is well established as regulatory method for the analysis of inorganic anions in environmental samples as there are few alternative methods which can determine multiple anions in a single analysis. However, there are relatively few regulatory methods for cation analysis which use IC. Methods for cation analysis tend to be based upon spectroscopic techniques, although IC offers the advantage of providing information on metal speciation. The main interferences in IC are generally other ions which elute within the timeframe of the ion(s) of interest, and the determination of trace ions in the presence of high levels of other ionic species remains the most difficult of analyses with this technique.
Laser Ablation Inductively Coupled Plasma Spectrometry in Environmental Analysis
Authors: Durrant Steven F.
Published: September 2006

Soon after the invention of the laser by Maiman, laser pulses were used for excitation and ionization of sample material for inorganic analysis by optical emission spectrometry (OES) or mass spectrometry (MS). This direct approach is complicated by the complexity of the laser–sample interaction and the need to optimize simultaneously the sampling and excitation (or ionization) steps. Use of a laser for solids sampling with separate atomization and excitation in an inductively coupled plasma (ICP) retains the advantages of direct solids analysis, including spatially resolved concentration data, and adds those attributable to the ICP, including wide elemental coverage, a linear dynamic range of six or more orders of magnitude, and excellent detection limits (DLs). The resulting techniques, denominated laser ablation/inductively coupled plasma/optical emission spectrometry (LA/ICP/OES) and laser ablation/inductively coupled plasma/mass spectrometry (LA/ICP/MS), are based on recording of relative emission intensities or ion count rates, respectively. Both methods are treated here, but emphasis is given to LA/ICP/MS, a rapidly developing technique in use for less than 15 years, which in addition to offering DLs typically 103times lower than those obtained by LA/ICP/OES, also offers isotope ratio analysis. Hardware, analytical procedures, performance, and prospects are addressed. The power and limitations of the methods are illustrated by environmental applications, including the analysis of metals, soils, rocks, and plastics.