CHAPTER 14 TRENDS IN ENVIRONMENTAL ANALYTICS

AND MONITORING

Jacek Namieśnik Department of Analytical Chemistry, Chemical Faculty,

Gdańsk University of Technology, G. Narutowicz 11/12, 80-952 Gdańsk, Poland

ABSTRACT Analytical procedures and techniques employed to determine different types of analytes in environmental matrices are of growing interest to analysts. The tasks and trends in the field of environmental analytics and monitoring are discussed in this chapter. In general, these trends fall into two main categories: - development and validation of new analytical procedures - design and introduction into analytical practice of new types of measuring devices

and analytical instruments. Some of these trends are discussed in a more detailed manner.

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1 INTRODUCTION Literature on analytical chemistry uses the term analytics more and more frequently. This new term emphasizes the interdisciplinary character of methods of obtaining information about material systems, i.e., the methods exceeding the strict definition of analytical chemistry. Analytics, so far practised mostly as analytical chemistry, and to a large extent identified with the work of chemists, has developed recently becoming a scientific discipline in its own right, whose role far exceeds chemistry and covers almost all branches of science and technology. Hence, analytics has become an interdisciplinary science. This interdisciplinary nature is revealed through a variety of phenomena utilized at the measurement stage. Analytics is a scientific discipline which embraces:

various areas of chemistry (particularly physical chemistry and biochemistry), physics, computer science, electronics, automation and robotics, material science, biology, instrumentation, chemometrics.

Even a cursory perusal of any analytical journal must lead one to the conclusion that trace and ultra-trace analysis is a domain of chemical analysis which is gaining in importance. This conclusion is corroborated not only by the feelings and opinions of analysts. By the current definition of the term 'trace component' proposed by the IUPAC, the limit from which we can talk about trace analysis is the concentration of 100 ppm (100 µg/g). Naturally, this limit is purely conventional and is not a constant. As recently as thirty years ago 'trace analysis' was understood to denote activities aiming to determine components at a concentration level one order of magnitude higher (i.e., below 1,000 ppm, or 0.1%).

Even today the determination of components at a concentration level of 100 ppm, even in samples with complex matrices, does not pose major problems and is done routinely in many laboratories. This is mainly due to the rapid development of instrumentation, or the science of the construction and use of monitoring and measuring devices. Hence, one may expect the definition of the term 'trace component' to change again soon [1].

Table 1 presents a classification of analytical methods and techniques by analyte concentration in the sample to be examined.

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TABLE 1 Classification of analytical methods and techniques by analyte concentration in a sample General name of analyte

Analyte

concentration

Examples

Sub-microtrace component < 1 ppt (< 10-8%)

Determination of dioxins in samples of various matrices

Ultra-microtrace component < 1 ppb (< 10-6%)

Determination of trihalomethanes in drinking water and human urine. Determination of volatile organic compounds in indoor air

Micro-trace component < 1 ppm (< 10-4%)

Determination of carbon monoxide in ambient air

Trace component < 100 ppm (< 0.01%)

Determination of methane in ambient air

Secondary component (admixture) < 1%

Determination of carbon dioxide in ambient air

Primary component 1-100% Determination of oxygen in waste gases. Determination of oxygen in flue gases.

It is possible to distinguish three areas of science and technology that spur the development of analytical methods and techniques employed in the determination of low and very low analyte contents in samples of various kinds. They are:

• technologies of the production of high-purity materials; to date, the purity of the cleanest man-made material is denoted by 11 N, which means that the sum total of all impurities it contains does not exceed 10-9%, or 10 ppt;

• genetic engineering and biotechnology; and • environmental protection.

The determination of ever lower concentrations of analytes has brought into common use special ways of expressing such concentrations. Table 2 lists the units employed to denote concentrations in trace analysis

Ecotoxicological considerations and the strive for an increasingly more accurate description of the state of environment pose a great challenge to analytical chemists in terms of the necessity of determining still lower concentrations of various analytes in samples having complex and even nonhomogeneous matrices. The task can be accomplished by one of the two approaches [2]:

by using more sensitive and selective, or even specific detectors. This approach can be exemplified by the introduction of the photo-ionisation detector (used in gas chromatography), which is more sensitive and more selective than the flame-ionisation detector which has been commonly used in GC,

by introducing to analytical procedures an additional step: isolation and/or enrichment of analytes prior to their final determination. This extra step facilitates removing the interference resulting from the components of a primary matrix (due to matrix simplification), but also, more importantly, it results in an increase in analyte concentration to a level above the detection limit of the method or the analytical

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instrument used. This approach makes possible routine determinations of analytes at the ppb level, or even determining analytes at concentration levels down to a fraction of ppq.

2 STAGES IN PREPARATION OF ENVIRONMENTAL SAMPLES FOR ANALYSIS The wide variety of environmental samples, related to their different states of aggregation, sampling location, matrix composition, as well as analyte type and concentration level, make it extremely difficult to present even the most basic information on sample preparation in a single article. A large number of operations can be performed during the sample preparation step. They can be performed in situ during sampling, or after the sample is delivered to the laboratory. Quite obviously, the manner in which a sample is processed depends on the final determination method. Independently of the type of sample and the analyte(s) determined, the analysts have to deal with specific problems of trace analysis. Each stage of sample preparation carries a risk of analyte loss or sample contamination. Thus, special measures must be taken to prevent these unwanted phenomena [3,4].

Apart from random errors, the potential for systematic errors is increased in trace analysis. The most common sources of systematic errors are related to:

• Differences in volatilities of sample components, • Adsorption and desorption of sample components onto/from the walls of containers

and instruments (memory effects), • Sample contamination caused by contact with laboratory air, • Change in sample composition caused by addition of chemical reagents, • Human factor. Table 2 lists basic operations and activities carried out during preparation of environmental samples for analysis

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TABLE 2 Sample preparation stages.

Sample type

Operations and activities Gaseous samples

Liquid samples

Solid samples

1. Carried out in situ Dust removal Drying Removal of interferences (e.g. deoxygenation) Suspended particulate matter (SPM) removal Preservation (chemical) Derivatization Isolation and/or preconcentration Transport

+ + +

+ +

+ + + + +

+ +

2. Carried out in the laboratory Drying Grinding Homogenization and mixing Preservation (thermal and/or chemical) Sieve analysis Mineralization Isolation and/or preconcentration Derivatization Analyte extraction Purification and removal of interferences Sample fractionation and partitioning Calibration and verification of the instruments

and methods Sample introduction to the instrument

+

+ + + + + +

+

+

+ +

+ + + + + + +

+

+ + + + + + + + + + + +

+

Even a cursory review of the literature indicates that chromatographic techniques overwhelmingly prevail at the component separation and quantitation stage. Table 3 lists the specific requirements of chromatographic techniques with respect to sample preparation [3].

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TABLE 3 Sample preparation for chromatographic analysis. No. Goal Operations 1. Assuring sample stability and

homogeneity during sample transport and storage

Grinding Homogenization Sieve analysis Drying Freeze drying Chemical preservation Thermal preservation

2. Removal of interferences Dust removal from gaseous samples Drying of gaseous samples Oxygen removal from gases SPM removal from water

3. Analyte conversion into a form suitable for:

Isolation and concentration Separation Determination

In-situ derivatization On-column derivatization Post-column derivatization

4. Matrix exchange into one compatible with the instrument

Analyte extraction using: - carrier gas stream

- supercritical fluid Application of membrane processes Application of thermal desorption for analyte

transfer from a solid sorbent bed to the chromatographic column

5. Bringing analyte concentration in the sample fed to the instrument to a level enabling quantitative analysis

Use of isolation and preconcentration techniques increasing analyte concentration (or amount) with respect to matrix components (effectiveness of this stage is characterized by so-called concentration factors)

6. Reducing solvent consumption Use of solventless sample preparation techniques

3 GREEN ANALYTICAL CHEMISTRY Introduction of the concept of green chemistry is closely related to the spreading of the principles of balanced development and the well visible trend towards their implementation in both chemical plants and laboratories. Starting from this general premise, one can develop a full set of more detailed principles which should become guidelines for chemists and production engineers to make their activities harmless (or to minimise their harmfulness) towards the environment. The best known set of such rules is the 12 principles of green chemistry, proposed in 1998, which may be found at the home-page of the American Chemical Society (www.acs.org/education/greenchem/principles.html).

Analytical chemistry and monitoring play an important role in estimation of the extent of the influence of chemists on the environment. As huge number of analytical methods and techniques has been introduced to the practice and the number of determinations is increasing in an avalanche-like manner. An illustrative example of this trend may be the size of the collection of analytical procedures by the US Environmental Protection Agency, which is more than 3500 procedures designed for the

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determination of more than 4000 analytes in water samples only, i.e., waters of different origin, like surface waters, drinking water, waste water, etc. And waters constitute just one of the four basic elements of the environment. It seems important to stress that analytical activities may also be performed in either a friendly or unfriendly way from the environmental point of view. Therefore, one can conclude that while there is growing pressure towards further development of green chemistry, such a development will be at least put at risk without the existence of green analytical chemistry. 3.1 Green analytical chemistry – a new approach towards chemical analysis The afore-mentioned 12 principles of green chemistry may be utilized to formulate the main features, determining the green character of analytical chemistry. The following should be treated as top priority [5]: • elimination (or, at least, significant reduction) of reagents, particularly organic

solvents, consumption from analytical procedures; • reduction of emission of vapours and gases, as well as liquid and solid waste

generated in analytical laboratories; • elimination of reagents displaying high toxicity and/or eco-toxicity from analytical

procedures (e.g., substituting benzene by other solvents); • reduction of labor and energy consumption of analytical procedures (per single

analyte). Table 4. presents a compilation of examples of implementation of green chemistry principles in analytical laboratories.

On the basis of the literature, data and observation of current trends in analytics and monitoring, one can conclude that there is particularly rapid progress in the development of just these analytical methods and techniques which assure observation of the principles of green analytical chemistry. Especially valuable are what are known as solventless techniques of sample preparation.

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TABLE 4 Operations carried out in an analytical laboratory essential for the implementation of the principles of the green analytical chemistry No. Target Way of implementation Remarks Examples

1

Total elimination of reagents and solvents from an analytical laboratory

Utilization - as much as possible - of the so called direct analyticaltechniques

The direct techniques permit the determination of analytes in a sample without any pretreatment or sample preparation

• Electrochemical methods (ion-selective electrodes)

• Atomic absorption spectroscopy with thermal excitation in a graphite furnace (GFAAS)

• Atomic emission spectroscopy with inductively coupled plasma (AES-ICP)

• Surface analysis techniques (SEM, SIMS, AES, XPS/ESCA, ISS)

• X-ray fluorescence • Remote analysis techniques for

measuring air pollution (Lidar, Sodar)

2 Reduction of the amounts of the reagents used

Reduction of the size of the analyzed samples (reduction of the scale of determinations) Carrying out the analyses right at the

li i (i i )

Financial savings due to reduced purchases of reagents, esp. of high purity. Pro-ecological factors like: • reduction of the amounts of

solutions containing potentially harmful reagents to the communal waste collection systems,

• reduced need for treatment of overdue reagents,

• no need to use chemical preservatives to stabilize samples du-ring their

• µ-Total Chemical Analysis Systems (µ-TAS)

• Utilization of the chip and micro-chip technology in analytical instruments (laboratory on the chip)

• utilization of immunoassays (IMA): • radioimmunoassays (RIA) • enzymatic immunoassays (EIA).

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sampling site (in situ) Application of so-called dry techniques of sample preparation for analysis

transportation and storage. It permits obtaining analytical information in real time or with a minimum delay. This factor becomes particularly important at: • preventing catastrophes and fai-

lures in chemical installations (fires, explosions, spills),

• making decisions concerning changes in a technological re-gime.

High temperature catalytic techniques of oxidation and reduction of analytes (instead of low temperature treatment of sample in solution).

3

Elimination or reduction of the amount of solvents used in an analytical procedure

Introduction of the so-called sol-ventless techniques to the analyti-cal practice

Financial savings due to: • reduced purchases of high puri-

ty solvents, • no need for organizing a system

of collection of used solvents, Pro-ecological fators like: • reduced risk of accidental

dispo-sal of used solvents to the was-tewater systems,

• reduced risk of exposure of laboratory personnel to the vapours of volatile organic compounds.

• Supercritical Fluid Extraction (SFE) • Membrane extraction systems

coupled directly (on-line) with measuring devices

• Gas extraction (stripping) of analytes

• Solid Phase Extraction (SPE) coupled with thermal desorption

4 Reduction of emission ofvapors and gases

Air-tight sealing of vessels and de-vices

Reduced exposure of lab staff to potentially harmful gases/vapours.

5 Reduction of labor and energy consumption

Automation and robotization of lab operation. Parallel determination of manyanalytes in a single analytical cycle.

Reduced energy consumption per analysis or per analyte

Wider utilization of hyphenated techniques.

• Chromatographic and related techniques

• SPE-GC, SPE-HPLC, SFE-SFC

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4 ROLE AND TASKS OF ENVIRONMENTAL ANALYTICS AND MONITORING According to a more and more common opinion, analytics and monitoring of environmental pollutants constitute the two pillars on which the entire environmental science is based. Consequently, one can share the opinion of some specialists that there exists already a separate field of chemical analytics named ecoanalytics. However, we should be aware of the fact that neither analytics nor monitoring as such solve any problems concerning pollution or degradation of specific elements of the environment. They are only powerful tools, which can provide information required for a reliable evaluation of the state of environment and the changes taking place, as well as for making correct decisions for sozotechnical actions.

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TABLE 5 Units employed to denote concentrations of trace and ultra-trace components.

Name of concentration

unit

Part per thousand

Part per million

Part per billion

Part per trillion

Part per quadrillion

Part per quintillion

Part per sextillion

Volume/volume concentration

vpth

(ppth v/v)

vpm

(ppm v/v)

vpb

(ppb v/v)

vpt

(ppt v/v)

vpq

(ppq v/v)

vpqui

(ppqui v/v)

vps

(pps v/v) Mass-mass concentration

ppth

ppm

ppb

ppt

ppq

ppqui

pps

Percentage (%)

10-1

10-4

10-7

10-10

10-13

10-16

10-19

Amount of analyte in 1 g sample

1

milligram (1 mg)

1

microgram (1 µg)

1

nanogram (1 ng)

1

picogram (1 pg)

1

femtogram (1 fg)

1

attogram (1 ag)

1

zeptogram (1 zg)

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271

In general, the role and tasks of analytics and environmental monitoring can be summarised as presented in Figure 1.

Application areas of analysis and

Identification of emission pollutants

sources

Evaluation of efficiency of

sozotechnical treatment

Assessment of effectrange of pollutants emission sources

Typical evaluation ofquality of particular

environmentalcompartments (agreement

with standards andregulations)

Studies of environmentalbackground and on

longterm trends

Exposuremeasurements

Chemical,biochemical andphotochemical

transformations ofenvironmental

pollutants

Pollutants transport paths

Ecological Emission

Investigations ofaccumulation and

metabolism ofpollutants by

living organisms

Mesurement of ratio

Studies on occuring in environmen

Effect of pollutants on clinic changes

Figure 1. Application areas of environmetal analysis and monitoring.

The above tasks can be accomplished through the application of a wide range of

procedures, analytical techniques and instruments. Monitoring should be considered as a specific branch of analytics where fully automated measuring devices are used. 5 DEVELOPMENT OF ENVIRONMENTAL ANALYTICS AND MONITORING Examination of scientific literature leads to the conclusion that there is a number of tendencies in the area of application of various analytical procedures and techniques in analytical practice. In general these tendencies fall into two different categories:

development, validation and application of new analytical procedures, design and construction of new measuring devices and analytical instruments for:

handling, transport and preliminary pre-treatment of environmental samples, isolation and/or preconcentration of analytes prior to their find determination, validation and calibration of measuring devices, separation, detection, identification of analytes, statistical and chemometrical evaluation of analytical data.

These two types and main tendencies are described shortly in Table 6

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TABLE 6 Main trends in the field of environmental analytics and monitoring

Type of trends Specific tendency Short description Solventless sample preparation techniques It is an example of application of “green chemistry” principles into analytical

practice

Development of speciation analytics Speciation analytics is the process loading to identification and determination of the different compounds and its different physical forms an element

Application of sum parameters (total parameters) Total parameters describe the total content of a given element in all the pollutants or in a particular subgroup of pollutants in a sample under investigation

Introduction of biomonitoring and bioanalytics

In practice the following problems are discussed: - the use of the results of chemical analytics of biota samples to evaluate pollution

of the abiotic part of the environment - faune and flore observation - immunoloanalysis and bioassays

Methodological

Simultaneous determination of many analytes using one sample in one analytical cycle

High-efficiency capillary columns used in chromatography are an excellent example of this approach 272

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New type of detectors and sensors including biosensors

Design and construction of array of chemical sensors (electronic nose and electronic tongue)

Application of multidimensional techniques

In multidimensional techniques, different characterization mechanisms (or systems) are coupled together. Sample components are subject to characterization by each of these mechanisms, usually applied in sequence. Consequently, components that could not be distinguished by one mechanism (or system), can often be easily distinguished based on the second mechanism. Multidimensional techniques are particularly powerful in characterization of very complex samples, for which no single characterization mechanism can offer sufficient resolving power.

Miniaturization of analytical instruments Production of analytical microsystems that fulfill chemical or biochemical functions (called also “laboratory on a chip”) Concept and development of so called µ-Total Chemical Analysis Systems (µ-TAS)

In situ measurements techniques Personal dosimeters and personal continuous monitors used to evaluate individual exposure constitute the special class of transportable measurement devices

Instrumental

Application of passive samplers

Compared with conventional active units passive samplers have the following advantages: - neither power sources nor bulky and expensive pumps are required - simple to use in in situ conditions

Expanding of spot tests

There are there main types of tests: - dry test - semi-dry test - wet test

Use of expert system

Expert system, also known as “knowledge-based systems”, attempt to model the human reasoning process. They permit a certain degree of computerization of analytical expertise, thus providing a vehicle for maintaining and communicating this knowledge

Development of remote sensing techniques Main achievements in this area are based on application of LIDAR (light detection and ranging) and SODAR (sound detection and ranging) techniques

Instrumental

Use of Geographic Information System (GIS) technology

The development is connected with: - advances in methodologies of data generation - development of remote sensing techniques - use of global positioning system (GPS)

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5.1 Solventless (solvent free) sample preparation techniques In recent years, rapid development of solventless sample preparation methods took place. A classification of solventless methods of sample preparation is shown in Figure 2. The great interest in this approach is due to both ecotoxicological and economic aspects: emission of sometimes toxic solvents into the environment is avoided; solvents of high purity are expensive and so are costs of recycling, e.g. by distillation [6].

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Solventless techniques of of samples for GC

Extraction of analytes from sample with a

stream of gas

Direct determination of analytes in a stream of gas

Head Space Analysis - HSA

Trapping analytes in a chromatographic column

Whole Column Cryotrapping - WCCT

Freezing analytes and their thermal releasing prior to the

determination stageCryotrapping - CT

Direct determination of analytesin a stream of gas or liquidflushing the extema side of

membrane

Membraneextraction

Collection of analytes from a stream ofgas on a sorbent bed and their releaseby thermal decomposition prior to thefinal determination stageMembraneExtraction with Sorbent Interface

- MESI, Hollow Fiber SamplingAnalysis - HFSA, On-Line

Membrane Extraction Microtrap -OLMEM, Membrane Purge andTrap - MPT, Pulse IntroductionMembrane Extraction - PIME,Semi Permeable Membrane

Devices - SPMD

Utilization of passive dosimeters of permeationtype at analyte collection stage and thermal

Dosage of analytes into amass spectrometer

Membrane Inlet MassSpectrometry - MIMS

Solid Phase Extraction -SPE

Solid Phase Microextraction- SPME[Sampling the analytes directly from the

medium of interest (gas,liquid)]

Utilization of a part of capillary column as anextraction element and thermal desorption forthe release of analytes - CoatedCapillary

Microextraction - CCME, ParallelCurrent - Open Tubular Liquid

Chromatograph PC-OTLC, Thick FilmOpen Tubular Trap - TFOTTThick Film,

Capillary Trap - TFCT

Sampling of the head space - Head Space- Solid Phase Microextraction

- HS SPME

Utilization of a sorbent bed inside the syringe needle for a

sample collection Inside Needle Capillary

Adsorption Trap - INCAT

Utilization of traps with a suitable solidsorbent -Purge and Trap - PT,

Closed Loop Stripping Analysis -CLSA-or a stationary phase on asupport - Packed PDMS trap -sorption tubes, denuders, passive

dosimeters - combined with thermalat the release stagedesorption

Utilization of an extraction membrane as analytecollecting medium in combination with thermaldesorptionThermal Membrane Desorption

Application - TMDA

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desorption for their release

Supercritical Fluid Extraction - SFE

Figure 2. Classification of the solventless methods of sample preparation

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5.2 The role of speciation in environmental analytics and monitoring According to the official definition which is currently under discussion at IUPAC speciation analysis is the process leading to the identification and determination of the different chemical and physical forms of an element existing in a sample. Although this definition tends to restrict the term speciation to the state of distribution of an element among different chemical species in a sample, in practice the use of this term is much wider, specifying either the transformation and/or the distribution of species, and the measure of their distribution. For the description of these processes the terms “species transformation” respectively, are suggested. The analytical activity involved in identifying and measuring species is hence defined as “speciation analysis” [7]. Generally speciation analytics plays a very important role in:

studies of geochemical cycles of elements and chemical compounds, determination of toxicity and ecotoxicity of selected compounds, quality control of food products, control of medicines and pharmaceutical products, technological process control; research on the impact of technological installations on the environment, examination of occupational exposure, clinical analysis.

Speciation analysis can be performed in at least five different types, depending on the aim and scope of the analytical investigation. Brief characteristics of basic types of speciation analysis and examples of their application are given in Table 7.

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TABLE 7 Short characteristics of basic types of speciation analysis

Type of speciation analysis

Area of application Remarks Examples

Physical speciation

Environmental pollution analyses (air, water, soil)

This type of speciation is extremely important from various points of view: chemical process investigations and biochemical processes going on in different elements of the environment.

Trace metals analysis (soluble and suspended fraction). Trace analysis of different forms present in soil and sediment after sequential extraction.

Chemical speciation

Screening speciation

Environmental pollution analyses. Food pollution analyses Ecotoxicology

It is the simplest case of speciation analysis, which leads to the detection and determination of one define analyte.

Determination of tributyltin in sea water, sediments, tissue. Determination of methylmercury in tissue

Group speciation

Environmental pollution analyses Food pollution analyses Ecotoxicology

This case of speciation analysis leads to the determination of the concentration level of the specific group of compounds or elements existing in different compounds and forms and at the specific oxidation level

Determination of chromium compounds Cr(VI). Determination of organic matter in samples by the assignation of summary parameters (i.e., TOC in water or TH in air). Determination of level of concentration of different forms of mercury (elementary, inorganic and organic)

Distribution speciation

Environmental pollution analyses Ecotoxicology

This type of speciation is connected in most cases with the analytes of biological samples

Determination of trace metals in blood serum and blood cells. Determination of heavy metals in plants.

Individual speciation

Environmental pollution analyses. Food pollution analyses. Ecotoxicology

The most difficult form of speciation analysis. Fractionation and separation techniques have played a particular role. Unique application of chromatography and coupled techniques in this area speciation analysis.

Identification and determination of chemical species defined as a molecular, complex, electronic or nuclear structure.

Application of total parameters (sum parameters) to the evaluation of the degree of pollution of the different elements of the environment.

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These parameters express the total content of a given element present in a sample in different chemical combinations and physical forms. Historically, the first total parameters used in analytics to determine the amount of organic matter in a sample being analyzed have been: Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD) in liquid and solid samples, and Total Hydrocarbons (TH) in air samples. Recently, the best-known parameter, which has found application in environmental analytics, is Total Organic Carbon (TOC).

The importance of determining total organic carbon content (TOC) was already recognised in 1931. Since that time literature has brought many reports arguing for the necessity of determining TOC, DOC and POC. The basic techniques for the determination of TOC in water have remained relatively unchanged for 25 years. Organic compounds are converted to CO2 using combinations of techniques that may include: a chemical oxidising agent, wet chemical oxidation (WCO method), ultraviolet irradiation (UV), high-temperature combustion, or high-temperature catalytic oxidation (HTCO method). CO2 is then measured using nondispersive IR absorption, microcoulometry, conductometric techniques, or a flame ionisation detector (after methanisation of CO2). Since many water samples contain inorganic forms of carbon (carbonate and bicarbonate ions), it is usually necessary to remove these species, typically using a gas stripping technique prior to measurement of TOC, or to directly measure total inorganic carbon (TIC) content of a sample as part of the TOC determination [8]. Present methods and techniques of determination of total parameters can be classified, taking into account the following: 1. Area of practical use. atmospheric air studies,

water and wastewater studies, soil and sediments studies.

2. The parameter determined total content of a given element in all pollutants present in a sample,

content of a given element in a given group of pollutants present in a sample. 3. Way of conducting chemical analysis directly in a sample,

after analytes extraction (extract analysis). 4. Method of extraction of analytes from the sample studied. 5. Mineralization technique before the final analysis dry techniques based on catalytic oxidation at high temperature,

wet oxidation at low temperature (with oxidant addition). Table 8 contains a brief description of techniques used for determination of total hydrocarbons present in gaseous samples.

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TABLE 8 Classification of total parameters used to characterize water pollution using determination of carbon as an example

Criterion

Names of parameters

Type of chemical combination

Total Organic Carbon (TOC)

Total Inorganic Carbon (CO

2

2-, HCO

3-, CO

2 solv) TIC

Total Carbon (TC) TC = TOC + TIC

Form of occurrence of chemical compounds

Dissolved Organic Carbon (DOC)

Suspended Organic Carbon (SOC)

Total Organic Carbon TOC = DOC + SOC

Volatility of organic compounds

Volatile Organic Carbon (VOC)

Non-Volatile Organic Carbon (NVOC)

Dissolved Organic Carbon DOC = VOC + NVOC

Method of isolation of organic compounds from water

Solvent extraction Extractable Organic Carbon (EOC)

Non-Extractable Organic Carbon (NEOC)

Dissolved Organic Carbon DOC = EOC + NEOC

Adsorption on a sorbent

Adsorbable Organic Carbon (AOC)

Non-Adsorbable Organic Carbon (NAOC)

Dissolved Organic Carbon DOC = AOC + NAOC

Extraction with a stream of gas

Purgeable Organic Carbon (POC)

Non-Purgeable Organic Carbon (NPOC)

Dissolved Organic Carbon DOC = POC + NPOC

5.3 Bioanalytics and biomonitoring Modern analytical techniques allow the acquisition of reliable results which provide the information necessary for proper evaluation of the degree of pollution in different parts of the environment, such as air, water or soil. However, the use of such techniques is often time- and labour-consuming, expensive, and it requires highly qualified personnel. Furthermore, many of these techniques can only be used in the laboratory. There is a growing need in everyday analytical practice for rapid and more specific methods, which would allow field measurements (in situ) in the on-line mode. Such a need is met by the analytical techniques utilizing biological material, e.g., living organisms or living matter (biota), as an integral element of the process of gaining analytical information. Such methods, due to the biological principle of operation, are often specific, which makes it possible to avoid the sample preparation step. In addition, the biological principle of operation makes them suitable for applications related to human health and safety. Devices using biological elements can be made portable, which makes them less expensive when compared with stationary devices. For these reasons, biological methods enjoy an ever-growing popularity both in monitoring and in analysis of environmental pollution. This tendency is sufficiently evident to be considered one of the significant trends of modern analysis. The idea of using organisms, or communities of organisms, to register and evaluate certain characteristics of the environment is based on the ecological theorem of equilibrium between the environmental factors and the requirements of the species, which can be traced back to the 16th century. At that time, certain forms of plant cover were already known to indicate the presence of ores in the ground while the composition of the vegetation was used to judge the fertility of the soil. With the

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beginning of the industrial era and the resulting increase in emissions, it became clear that organisms are not only capable of indicating the "natural" characteristics of a location, but also provide qualitative and quantitative information on changes in the environment brought about by man. As far back as 1866, Nylander drew conclusions on air pollution from the species composition of the lichens occurring naturally in Luxembourg. Since then, an immense amount of literature has been published on bacteria, fungi, plants, and animals, from both the aquatic and the terrestrial biotope, that provide information on the abiotic condition of their environment. A general classification of biological methods used in the field of environmental analysis and monitoring is shown in Figure 3.

biological methods in analitycs

BiomonitoringBioanalytics(Bioassay)

Application of bioindicators - visual indicators (Biological Early Warning System - BEWS) - lichens and vertebrates;- analysis of species composition- retrospective indicators (pollen analysis, diatomeceonus analysis,- prognostic indicators (water blooming, plant successions)

Analysis of samples of livingmatter (biota)

Application of biosensors inclassical monitoring

Utilization of biologicalcomponents as thebasis of part of an

analytical procedure(immunosorbents,

biocatalysts, biocolums)

Application of differenttypes of biosensors:- enzymatic andbioaffinity;- bacterial and tissue sensors

Application of biotests(Immunoussay)

Figure 3. Classification of biological methods utilized in enviro-nmental analytics and

monitoring 5.4 Passive sampling of analytes Passive sampling will be defined as any sampling technique based on free flow of analyte molecules from the sampled medium to a collected medium as a result of a difference in chemical potentials of the analyte between the two media. Net flow of analyte molecules from one medium to the other continues until equilibrium is established in the system, or until the sampling session is terminated by the user [9]. In Table 9 a classification of passive technique is presented.

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TABLE 9 Classification of passive sampling parameters No Classification parameter Characteristic Type of passive device

1. Medium used for sampling

Dedicated device incorporating a trapping medium Living organisms

Passive sampler Solid phase microextraction (SPME) fiber Semi-permeable membrane device Single solvent droplet Bioindicators Biomonitors

2. Sample type

Gaseous - atmospheric air - indoor air - workplace atmosphere Liquid - surface waters - potable water

Solid - soil

Passive samplers SPME Bioindicators Biomonitors Passive samplers SPMDs SPME Bioindicators Biomonitors Passive samplers SPME

3. Type of analytical information acquired

Long-term time-weighted average (TWA) concentration Individual exposure Peak concentration 8-h average concentration

Area monitors Personal samplers

4. Manner in which analytical information is acquired

Observation of living organisms Determination of the amount of analyte collected by the sampler

Bioindicators Passive samplers SPME Biomonitors

Pasive sampling of analytes from solid matrices (such as soil, bottom sediment

and compost) has a relatively short history, with papers devoted to this topic appearing in the past few years only. The main obstacle in this case is the difficulty in converting the amount of analyte collected by the sampler to its concentration in the solid matrix. Accurate conversion is often impossible, therefore in most cases passive sampling is used for screening purposes only [10]. Several different approaches to passive sampling of solids have been proposed in the literature. Probably the most widespread is the application of SPMD. The device can be protected against damage, for example by strips of precleaned cotton fabric. Nilsson et al. used a remotely actuated SPME device for soil gas sampling. So-called Petrex sample collectors comprise activated charcoal adsorbent fused to a ferromagnetic wire in a glass test tube. They are typically buried 30-45 cm deep with open end down and left in place from overnight to several weeks. A device based on similar principle was used for sampling of chloroform from soil. The Gort-Sober screening module is a device in which sorbent containers are enclosed inside expanded

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tubular PTFE membranes resembling shoestrings. The analytes are usually recovered from the sorbent bt thermal desorption. Table 10 presents main application areas of passive sampling. Overall, this technique is most often used for the determination of TWA concentrations of analytes. Passive sampling is particularly suited for this purpose, because a single device and single determination are sufficient to yield information on the TWA concentration of analyte during the entire exposure period. TABLE 10 Main application areas of passive sampling

Medium Sample type Measurement goals

Atmospheric air Determination of time-weighted average concentrations over long periods of time (area monitors)

Indoor air Determination of time-weighted average concentration

Gaseous

Workplace air Determination of 8-hr time-weighted average concentration ------------------------------------------------Determination of personal exposure (personal dosimeters)

Liquid Surface waters Determination of time-weighted average concentrations over long periods of time

By contrast, grab sampling represents conditions only at the time of sampling, so,

for accurate determination of the TWA concentration, it is necessary, to collect enough samples to cover the entire period of interest. The number of samples collected in this way can be quite large to gain the same TWA information. If the samples are not analyzed on-site, it is necessary to use a corresponding number of sampling devices or containers, which can be expensive; besides, the overall cost of the analysis is the product of the cost of a single determination and the number of individual grab samples. Thus, accurate determination of TWA concentrations using grab samples can be prohibitively expensive, especially if the period of interest is long. Moreover, by concentrating the analytes on site, passive sampling avoids problems associated with changes in the composition of the sample during transport and/or storage. However, grab sampling is better suited to the detection of short-term changes in analyte concentration.

5.4 Quality Assurance/Quality Control (QA/QC) Quality assurance (QA), quality control (QC) and associated Good Laboratory Practice (GLP) are essential components of all activities in the field of environmental analytics and monitoring. By definition QA refers to all the actions, procedures, checks and decisions undertaken to ensure and representativeness and integrity of samples and accuracy and reliability of analytical results. QC comprises those actions that monitor and measure the effectiveness of QA procedures with respect to defined objectives. This might include checking of equipment cleanliness, duplicate sampling, measurement of field and laboratory blanks and the analysis of replicates and reference materials.

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Quality Control is therefore an essential component of a QA program and both are usually jointly recognized by the implementation of good QA/QC as an essential part of good laboratory practice. It is now widely accepted that there are three essential elements to laboratory quality assurance which assist the process of facilitating manual recognition of results. These elements are: - accreditation - use of validated analytical methods - participation in laboratory proficiency testing. FINAL REMARKS This paper has been prepared on the basis of series of review publications [1-10] which were published during the last few years. Broader treatment of the issues discussed here, including the trends and problems related to analytics and monitoring can be found in these papers. LITERATURE [1] Namieśnik J, Crit. Rev. Anal. Chem., 32, 271 (2002). [2] Namieśnik J., Crit. Rev. Anal. Chem., 30, 221 (2000). [3] Namieśnik J., Pol. J. Environ. Stud, 10, 127 (2001). [4] Namieśnik J. and Górecki T., Pol. J. Environ. Stud, 10, 77 (2001). [5] Namieśnik J., J. Sep. Sci., 24, 151 (2001). [6] Namieśnik J. and Wardencki W., JHRC, 23, 297 (2000). [7] Kot A. and Namieśnik J., Trends Anal. Chem., 19, 69 (2000). [8] Namieśnik J. and Górecki T., Am. Lab., 34, 18, (2002) [9] Górecki T. and Namieśnik J., Trends Anal. Chem., 21, 276 (2002). [10] Namieśnik J. and Zygmunt B., Chromatographia-Suppl, 56, S-9, 2002.

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