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Recent trends in the instrumental analysis of geochemical materials
106
trends in analytical chemistry, vol. 10, no. 4,199l
Recent trends in the instrumental analysis of geochemical materials
Introduction The previous articles in this series have investigated recent trends in the instrumental analysis of trace metals’ and organic* compounds. In this article we report on trends in the instrumental analysis of geochemical materials. Many definitions are available for geochemistry. For the purposes of this article geochemistry is the science dealing with the chemistry of the earth as a whole, and its components, as well as with the distribution and migration of the chemical elements within the earth (in space and in time). The wide use of instrumental analytical techniques to geochemical materials had its beginning after the second world war. The most important stimulus to the application of instrumental techniques for geochemical analysis seems to have been the lunar exploration programme of the 1970’s. A network of special laboratories was established for the analysis of lunar samples and procedures were worked out to allow unprecedented performances as regards precision, accuracy, sensitivity and miniaturization. Consequently, at the end of the 1970’s and in the early 1980’s the procedures devel-
TABLE I. Distribution 1979-1988
l
oped for the analysis of lunar materials were applied to terrestrial samples.
T. Braun and S. Zsindely Budapest,Hungary
(%) of instrumental
Data and method We assume that the open scientific literature gives an adequate reflection of the trends and tendencies in the fields it deals with3. We have computed the number of times the various instrumental analytical techniques were used to determine different components in geochemical matrices as reported in the biennial geochemistry reviews published in Analytical Chemistry4-8. The data were transfered onto our computer for further manipulation. By classifying the various instrumental techniques according to the Analytical Abstracts indexing rules’, which are based on the physical principles involved in the measurement process, we noted approximately 150 different instrumental techniques. Some of these overlap considerably. They were merged into 6 groups (see Glossary). Two aspects of this approach should be noted. 0 The different instrumental techniques covered here were not selected, i.e. defined, by us (see above); the same is true for the types of geochemical matrices considered.
techniques
used in the determination
As one paper can refer to the use of many instrumental techniques, our analysis covers the number of uses of these techniques and not the number of papers on instrumental analytical techiques.
Results and discussion The results are presented in Tables I-IV. In all the tables percentages sum up vertically. Although the tables are self-explanatory, a few comments are in order. As can be seen in Table I, optical and nuclear techniques are most commonly used for elemental analysis in geochemical samples. The potential of chromatography for analyzing these matrices is not yet fully appreciated, although ion chromatography began to gain terrain during the second half of the 1980’s (e.g. for halogens and anions). In addition, hyphenated methods, mainly used in the developed countries, are also being applied more and more extensively. Table II shows an interesting ranking of groups of instrumental techniques for the analysis of different elements. Taking optical procedures as an example, we see the following ranking: heavy metals > multielement determinations > noble metals > other non-metals > alkali earth
of groups of elements
in geochemical
samples
in
Abbreviations: ALK = alkali metals; ALE = alkali earth metals; HME = heavy metals; OLM = other light metals; NOM = noble metals; REE = rare earth elements; ACT = actinides; GAS = gases; HAL = halogens; ONM = other non-metals; ANI = anions; MUL = multielements.
Optical Nuclear Electrical Chromatography Miscellaneous Hyphenated
ALK
ALE
HME
OLM
NOM
REE
ACT
GAS
HAL
ONM
AN1
MUL
41.5 46.3 0.0 7.3 0.0 4.9
29.0 61.4 0.0 3.2 1.6 4.8
48.3 37.8 2.6 2.0 1.9 7.4
22.2 61.2 0.0 0.0 0.0 16.6
59.3 17.7 5.3 7.1 0.0 10.6
36.9 41.2 0.7 3.5 0.0 17.7
12.5 50.1 8.3 8.3 0.0 20.8
33.3 66.7 0.0 0.0 0.0 0.0
18.0 20.0 22.0 34.0 2.0 4.0
33.9 27.3 3.3 10.7 5.0 19.8
23.1 0.0 7.7 38.4 30.8 0.0
36.1 40.9 1.0 4.9 0.5 16.6
trends in analytical chemistry,
vol. IO, no. 4,1991
107
TABLE II. The weight (%) of instrumental techniques of elements in geochemical samples in 1979-1988
in the determination
of groups
Abbreviations: OPT = optical methods; NUCL = nuclear methods; ELEC = electrical methods; CHROM = chromatography; MISC = miscellaneous; HYPH = ‘hyphenated’ methods.
Alkali metals Alkali earth metals Heavy metals Other light metals Noble metals Actinides Gases Halogens Other non-metals Anions Multielement det.
OPT
NUCL
ELEC
CHROM
MISC
HYPH
3.1 3.2 46.5 0.7 12.0 0.5 1.3 1.6 7.4 1.1 13.3
3.8 7.6 40.3 2.2 4.0 2.4 2.8 2.0 6.6 0.0 16.7
0.0 0.0 33.3 0.0 14.3 4.8 0.0 26.1 9.5 4.8 4.8
3.7 2.5 13.6 0.0 9.9 2.5 0.0 21.0 16.0 12.3 12.3
0.0 3.7 27.1 0.0 0.0 0.0 0.0 3.7 22.2 29.6 3.7
1.3 2.0 26.7 2.0 8.0 3.3 0.0 1.3 16.0 0.0 22.7
TABLE III. Distribution (%) of instrumental logical matrices in 1979-1988
techniques
used in the analysis
of geo-
Abbreviations: PHOS = phosphates; SIL = silicates; CLAY = clays, soils; CARB = cabonates; OXIDE = oxides, hydroxides, sulphides; SULPH = sulphates; HAL = halides; ORES = ores, fuels; MISC = miscellaneous. PHOS Optical Nuclear Electrical Chromatogr. Miscellan. Hyphenated
TABLE matrices
37.4 31.3 0.0 18.8 0.0 12.5
SIL 47.1 35.0 3.3 2.4 4.9 7.3
CLAY 42.9 21.4 3.6 3.6 21.4 7.1
CARB
51.6 19.4 0.0 9.7 3.2 16.1
63.6 18.2 0.0 0.0 0.0 18.2
IV. The weight of instrumental in 1979-1988
OXIDE
techniques
SULPH 75.0 0.0 0.0 0.0 25.0 0.0
HAL 33.3 0.0 33.4 0.0 0.0 33.3
ORES 37.3 44.7 2.4 3.6 6.0 6.0
MISC 48.5 33.5 2.7 5.5 3.8 6.0
used in the analysis of geological
Abbreviations as in Table II. OPT
NUCL
ELEC
CHROM
MISC
Phosphates Silicates Clays, soils Carbonates
2.7 26.1 5.4 3.2
3.1 26.9 3.7 1.3
0.0 30.8 7.7 0.0
13.0 13.0 4.3 0.0
23.1 23.1 0.0
5.4 24.3 5.4 5.4
Oxides, hydroxides, sulphides Sulphates Halides Ores, fuels Miscellaneous
7.2 1.4 0.5 14.0 39.5
3.8 0.0 0.0 23.1 38.1
0.0 0.0 7.7 15.4 38.4
13.0 0.0 0.0 13.1 43.6
3.8 3.8 0.0 19.2 27.0
13.5 0.0 2.7 13.5 29.8
metals > alkali metals. For nuclear procedures, the ranking is: heavy metals > multielement determinations > alkali earth > metals > other non-metals > noble metals > alkali metals. Tables III and IV present the frequencies of use of instrumental techniques for the analysis of different types of geochemical samples.
0.0
HYPH
In addition to the statistics on the uses of different instrumental techniques as reported in the literature, we collected data on the same distribution as applied to the analysis of geochemical reference standards (GRS) during the 1959-1988 period. The data are shown in Table V; they indicate that for this important type of samples and determinations nu-
Glossary Instrumental niques
analytical
tech-
Optical methods: spectrophotometry, calorimetry and polarimetry, turbidimetry, fluorimetry, vibrational spectroscopy, atomic absorption spectroscopy, mass spectrometry, nuclear magnetic resonance, X-ray spectrometry, X-ray diffractometry, and related methods. Nuclear methods: neutron activation analysis, radiometry, gamma-spectrometry, Xray fluorimetry and related methods. Electroanalytical
methods:
potentiometry, coulometry, amperometry, conductometry, polarography, voltammetry, and related methods. Chromatography: gas, columnn liquid, planar (thin-layer, paper) and other related methods, including pyrolysis gas chromatography. Miscellaneous: thermal methods (thermometry, thermogravimetry, enthalpymetry, calorimetry etc.), kinetic, enzymatic methods, as well as methods which could not be ordered in any other group. ‘Hyphenated methods’: combined instrumental methods, i.e. gas chromatography-mass spectrometry, etc.
clear analytical techniques (especially neutral activation analysis) rank a very solid first. In a future article in this ‘trends’ series we will explore the distribution of individual instrumental techniques within the merged groups in Tables I-IV. This will allow us to relate the frequency distributions of the different techniques to trends in produc-
trendsin analyticalchemistry, vol. 10, no. 4,199l
108
TABLE V. Instrumental standards (GRS)a
techniques
reference
3 T. Braun, E. Bujdod bert, The Literature
and A. Schu-
of Analytical Scientometric Evalu-
Instrumental technique
1950-1959 (%)
1960-1969 (%)
1970-1979 (%)
1980-1988 (%)
2.0
13.3 _ 12.1 7.1 2.7 4.9
32.6 1.1 13.8 18.4 3.0 3.8
29.5 18.9 15.2 15.0 2.1 1.0
95.3
59.5,
27.3
18.3
1.5
Neutron activation analysis ICP spectroscopy X-ray fluorescence Atomic absorption spectrometry Mass spectrometry Colorimetry Other methods (including chemical) a Adapted from I. Roelandts, (1986) 265; 11 (1987) 133.
used in the analysis of geochemical
_ 1.2 -
Chemistry: A ation, CRC Press, Boca Raton,
FL, 1987. 4 C. B. Moore, Anal. Chem., 53 (1981) 38R. 5 C. B. Moore and J. A. Canepa, Anal. Chem., 55 (1983) 198R. 6 C. B. Moore and J. A. Canepa, Anal. Chem., 57 (1985) 88R.
Geostandard Newsletter, 12 (1988) 391; 1 (1987) 261, 10
7 F. E. Lichte, J. L. Seeley, L. L. Jackson, D. M. McKnown and J. E. Taggart, Anal. Chem., 59 (1987) 197R. 8 L. L. Jackson, D. M. McKnown, J. E. Taggart, P. J. Lamothe and F. E. Lichte, Anal. Chem., 61 (1989) 109R.
tion and commercialization of analytical instruments. Although this latter type of data is quite scarce and in general not unobtrusive, exceptions are available. Recent reports have shown that in Japan, for example, the number of ICP spectrometers in use has increased by more than one order of magnitude during the 1980-1988 period”. It is difficult to predict the direction in which instrumental techniques are moving. The overall picture shows a tendency towards an intensification in the use of sophisticated spectrometries, sensors and
sensing (mainly electroanalytical), chromatographies and hyphenated procedures. However, these tendencies differ according to country and/ or geopolitical region and the differences between the developed nations and most of the lesser developed countries will no doubt persist for some time’l.
References 1 T. Braun
and S. Zsindely,
Trends
Anal. Chem., 9 (1990) 144. 2 T. Braun and S. Zsindely, Anal. Chem., 9 (1990) 309.
Trends
9 Analytical Abstracts, Royal Society of Chemistry, Cambridge. 10 R. Hara, Anal. Chem., 62 (1990) 1240A.
11 T. Braun, Fresenius’ Z. Anal. Chem., 328 (1987) 1.
Professor T. Braun is at the Institute of Inorganic and Analytical Chemistry, L. EiitvSs University, P.O. Box 123, 1443 Budapest, Hungary and at the Information Science and Scientometric Research Unit (ISSRU), Library of the Hungarian Academy of Sciences, Budapest, Hungary. Dr. S. Zsindely is at the ISSRU, Budapest, Hungary.
meeting report Analytical Science in Europe
held in Brussels, Belgium,
1 l-l
2
The first symposium organised by the European Regional Section of the Association of Official Analytical Chemists (AOAC) was attended by about 200 analysts from 21 countries. It addressed the role of analytical measurement in Europe and the theme running throughout the meeting was Valid Analytical Measurement.
Most products that are traded are subjected to some form of regulation, rules or standards and they frequently end up in the laboratory for analysis. Products passing through customs may for tariff classification purposes require chemical analysis. On January 1, 1993 the customs barriers within the European Community will be removed and goods will be permitted to move freely from one Member State to another. In order to prevent the physical barriers being replaced by technical barriers, national legislations and technical standards are currently being harmonised.
Dr P. Gray of the European Commission focused on the developments that are underway to prepare Community food law for the Single European Market. The legislative objective is to: l permit free movement of goods, l protect public health, l provide consumers with both protection and information and l to provide the necessary public controls to ensure enforcement of a, b and c. Concerning the technical aspects, the Commission does not intend to prescribe methods of analysis for laboratories engaged in public control,
trends in analytical chemistry, vol. 10, no. 4,199l
Recent trends in the instrumental analysis of geochemical materials
Introduction The previous articles in this series have investigated recent trends in the instrumental analysis of trace metals’ and organic* compounds. In this article we report on trends in the instrumental analysis of geochemical materials. Many definitions are available for geochemistry. For the purposes of this article geochemistry is the science dealing with the chemistry of the earth as a whole, and its components, as well as with the distribution and migration of the chemical elements within the earth (in space and in time). The wide use of instrumental analytical techniques to geochemical materials had its beginning after the second world war. The most important stimulus to the application of instrumental techniques for geochemical analysis seems to have been the lunar exploration programme of the 1970’s. A network of special laboratories was established for the analysis of lunar samples and procedures were worked out to allow unprecedented performances as regards precision, accuracy, sensitivity and miniaturization. Consequently, at the end of the 1970’s and in the early 1980’s the procedures devel-
TABLE I. Distribution 1979-1988
l
oped for the analysis of lunar materials were applied to terrestrial samples.
T. Braun and S. Zsindely Budapest,Hungary
(%) of instrumental
Data and method We assume that the open scientific literature gives an adequate reflection of the trends and tendencies in the fields it deals with3. We have computed the number of times the various instrumental analytical techniques were used to determine different components in geochemical matrices as reported in the biennial geochemistry reviews published in Analytical Chemistry4-8. The data were transfered onto our computer for further manipulation. By classifying the various instrumental techniques according to the Analytical Abstracts indexing rules’, which are based on the physical principles involved in the measurement process, we noted approximately 150 different instrumental techniques. Some of these overlap considerably. They were merged into 6 groups (see Glossary). Two aspects of this approach should be noted. 0 The different instrumental techniques covered here were not selected, i.e. defined, by us (see above); the same is true for the types of geochemical matrices considered.
techniques
used in the determination
As one paper can refer to the use of many instrumental techniques, our analysis covers the number of uses of these techniques and not the number of papers on instrumental analytical techiques.
Results and discussion The results are presented in Tables I-IV. In all the tables percentages sum up vertically. Although the tables are self-explanatory, a few comments are in order. As can be seen in Table I, optical and nuclear techniques are most commonly used for elemental analysis in geochemical samples. The potential of chromatography for analyzing these matrices is not yet fully appreciated, although ion chromatography began to gain terrain during the second half of the 1980’s (e.g. for halogens and anions). In addition, hyphenated methods, mainly used in the developed countries, are also being applied more and more extensively. Table II shows an interesting ranking of groups of instrumental techniques for the analysis of different elements. Taking optical procedures as an example, we see the following ranking: heavy metals > multielement determinations > noble metals > other non-metals > alkali earth
of groups of elements
in geochemical
samples
in
Abbreviations: ALK = alkali metals; ALE = alkali earth metals; HME = heavy metals; OLM = other light metals; NOM = noble metals; REE = rare earth elements; ACT = actinides; GAS = gases; HAL = halogens; ONM = other non-metals; ANI = anions; MUL = multielements.
Optical Nuclear Electrical Chromatography Miscellaneous Hyphenated
ALK
ALE
HME
OLM
NOM
REE
ACT
GAS
HAL
ONM
AN1
MUL
41.5 46.3 0.0 7.3 0.0 4.9
29.0 61.4 0.0 3.2 1.6 4.8
48.3 37.8 2.6 2.0 1.9 7.4
22.2 61.2 0.0 0.0 0.0 16.6
59.3 17.7 5.3 7.1 0.0 10.6
36.9 41.2 0.7 3.5 0.0 17.7
12.5 50.1 8.3 8.3 0.0 20.8
33.3 66.7 0.0 0.0 0.0 0.0
18.0 20.0 22.0 34.0 2.0 4.0
33.9 27.3 3.3 10.7 5.0 19.8
23.1 0.0 7.7 38.4 30.8 0.0
36.1 40.9 1.0 4.9 0.5 16.6
trends in analytical chemistry,
vol. IO, no. 4,1991
107
TABLE II. The weight (%) of instrumental techniques of elements in geochemical samples in 1979-1988
in the determination
of groups
Abbreviations: OPT = optical methods; NUCL = nuclear methods; ELEC = electrical methods; CHROM = chromatography; MISC = miscellaneous; HYPH = ‘hyphenated’ methods.
Alkali metals Alkali earth metals Heavy metals Other light metals Noble metals Actinides Gases Halogens Other non-metals Anions Multielement det.
OPT
NUCL
ELEC
CHROM
MISC
HYPH
3.1 3.2 46.5 0.7 12.0 0.5 1.3 1.6 7.4 1.1 13.3
3.8 7.6 40.3 2.2 4.0 2.4 2.8 2.0 6.6 0.0 16.7
0.0 0.0 33.3 0.0 14.3 4.8 0.0 26.1 9.5 4.8 4.8
3.7 2.5 13.6 0.0 9.9 2.5 0.0 21.0 16.0 12.3 12.3
0.0 3.7 27.1 0.0 0.0 0.0 0.0 3.7 22.2 29.6 3.7
1.3 2.0 26.7 2.0 8.0 3.3 0.0 1.3 16.0 0.0 22.7
TABLE III. Distribution (%) of instrumental logical matrices in 1979-1988
techniques
used in the analysis
of geo-
Abbreviations: PHOS = phosphates; SIL = silicates; CLAY = clays, soils; CARB = cabonates; OXIDE = oxides, hydroxides, sulphides; SULPH = sulphates; HAL = halides; ORES = ores, fuels; MISC = miscellaneous. PHOS Optical Nuclear Electrical Chromatogr. Miscellan. Hyphenated
TABLE matrices
37.4 31.3 0.0 18.8 0.0 12.5
SIL 47.1 35.0 3.3 2.4 4.9 7.3
CLAY 42.9 21.4 3.6 3.6 21.4 7.1
CARB
51.6 19.4 0.0 9.7 3.2 16.1
63.6 18.2 0.0 0.0 0.0 18.2
IV. The weight of instrumental in 1979-1988
OXIDE
techniques
SULPH 75.0 0.0 0.0 0.0 25.0 0.0
HAL 33.3 0.0 33.4 0.0 0.0 33.3
ORES 37.3 44.7 2.4 3.6 6.0 6.0
MISC 48.5 33.5 2.7 5.5 3.8 6.0
used in the analysis of geological
Abbreviations as in Table II. OPT
NUCL
ELEC
CHROM
MISC
Phosphates Silicates Clays, soils Carbonates
2.7 26.1 5.4 3.2
3.1 26.9 3.7 1.3
0.0 30.8 7.7 0.0
13.0 13.0 4.3 0.0
23.1 23.1 0.0
5.4 24.3 5.4 5.4
Oxides, hydroxides, sulphides Sulphates Halides Ores, fuels Miscellaneous
7.2 1.4 0.5 14.0 39.5
3.8 0.0 0.0 23.1 38.1
0.0 0.0 7.7 15.4 38.4
13.0 0.0 0.0 13.1 43.6
3.8 3.8 0.0 19.2 27.0
13.5 0.0 2.7 13.5 29.8
metals > alkali metals. For nuclear procedures, the ranking is: heavy metals > multielement determinations > alkali earth > metals > other non-metals > noble metals > alkali metals. Tables III and IV present the frequencies of use of instrumental techniques for the analysis of different types of geochemical samples.
0.0
HYPH
In addition to the statistics on the uses of different instrumental techniques as reported in the literature, we collected data on the same distribution as applied to the analysis of geochemical reference standards (GRS) during the 1959-1988 period. The data are shown in Table V; they indicate that for this important type of samples and determinations nu-
Glossary Instrumental niques
analytical
tech-
Optical methods: spectrophotometry, calorimetry and polarimetry, turbidimetry, fluorimetry, vibrational spectroscopy, atomic absorption spectroscopy, mass spectrometry, nuclear magnetic resonance, X-ray spectrometry, X-ray diffractometry, and related methods. Nuclear methods: neutron activation analysis, radiometry, gamma-spectrometry, Xray fluorimetry and related methods. Electroanalytical
methods:
potentiometry, coulometry, amperometry, conductometry, polarography, voltammetry, and related methods. Chromatography: gas, columnn liquid, planar (thin-layer, paper) and other related methods, including pyrolysis gas chromatography. Miscellaneous: thermal methods (thermometry, thermogravimetry, enthalpymetry, calorimetry etc.), kinetic, enzymatic methods, as well as methods which could not be ordered in any other group. ‘Hyphenated methods’: combined instrumental methods, i.e. gas chromatography-mass spectrometry, etc.
clear analytical techniques (especially neutral activation analysis) rank a very solid first. In a future article in this ‘trends’ series we will explore the distribution of individual instrumental techniques within the merged groups in Tables I-IV. This will allow us to relate the frequency distributions of the different techniques to trends in produc-
trendsin analyticalchemistry, vol. 10, no. 4,199l
108
TABLE V. Instrumental standards (GRS)a
techniques
reference
3 T. Braun, E. Bujdod bert, The Literature
and A. Schu-
of Analytical Scientometric Evalu-
Instrumental technique
1950-1959 (%)
1960-1969 (%)
1970-1979 (%)
1980-1988 (%)
2.0
13.3 _ 12.1 7.1 2.7 4.9
32.6 1.1 13.8 18.4 3.0 3.8
29.5 18.9 15.2 15.0 2.1 1.0
95.3
59.5,
27.3
18.3
1.5
Neutron activation analysis ICP spectroscopy X-ray fluorescence Atomic absorption spectrometry Mass spectrometry Colorimetry Other methods (including chemical) a Adapted from I. Roelandts, (1986) 265; 11 (1987) 133.
used in the analysis of geochemical
_ 1.2 -
Chemistry: A ation, CRC Press, Boca Raton,
FL, 1987. 4 C. B. Moore, Anal. Chem., 53 (1981) 38R. 5 C. B. Moore and J. A. Canepa, Anal. Chem., 55 (1983) 198R. 6 C. B. Moore and J. A. Canepa, Anal. Chem., 57 (1985) 88R.
Geostandard Newsletter, 12 (1988) 391; 1 (1987) 261, 10
7 F. E. Lichte, J. L. Seeley, L. L. Jackson, D. M. McKnown and J. E. Taggart, Anal. Chem., 59 (1987) 197R. 8 L. L. Jackson, D. M. McKnown, J. E. Taggart, P. J. Lamothe and F. E. Lichte, Anal. Chem., 61 (1989) 109R.
tion and commercialization of analytical instruments. Although this latter type of data is quite scarce and in general not unobtrusive, exceptions are available. Recent reports have shown that in Japan, for example, the number of ICP spectrometers in use has increased by more than one order of magnitude during the 1980-1988 period”. It is difficult to predict the direction in which instrumental techniques are moving. The overall picture shows a tendency towards an intensification in the use of sophisticated spectrometries, sensors and
sensing (mainly electroanalytical), chromatographies and hyphenated procedures. However, these tendencies differ according to country and/ or geopolitical region and the differences between the developed nations and most of the lesser developed countries will no doubt persist for some time’l.
References 1 T. Braun
and S. Zsindely,
Trends
Anal. Chem., 9 (1990) 144. 2 T. Braun and S. Zsindely, Anal. Chem., 9 (1990) 309.
Trends
9 Analytical Abstracts, Royal Society of Chemistry, Cambridge. 10 R. Hara, Anal. Chem., 62 (1990) 1240A.
11 T. Braun, Fresenius’ Z. Anal. Chem., 328 (1987) 1.
Professor T. Braun is at the Institute of Inorganic and Analytical Chemistry, L. EiitvSs University, P.O. Box 123, 1443 Budapest, Hungary and at the Information Science and Scientometric Research Unit (ISSRU), Library of the Hungarian Academy of Sciences, Budapest, Hungary. Dr. S. Zsindely is at the ISSRU, Budapest, Hungary.
meeting report Analytical Science in Europe
held in Brussels, Belgium,
1 l-l
2
The first symposium organised by the European Regional Section of the Association of Official Analytical Chemists (AOAC) was attended by about 200 analysts from 21 countries. It addressed the role of analytical measurement in Europe and the theme running throughout the meeting was Valid Analytical Measurement.
Most products that are traded are subjected to some form of regulation, rules or standards and they frequently end up in the laboratory for analysis. Products passing through customs may for tariff classification purposes require chemical analysis. On January 1, 1993 the customs barriers within the European Community will be removed and goods will be permitted to move freely from one Member State to another. In order to prevent the physical barriers being replaced by technical barriers, national legislations and technical standards are currently being harmonised.
Dr P. Gray of the European Commission focused on the developments that are underway to prepare Community food law for the Single European Market. The legislative objective is to: l permit free movement of goods, l protect public health, l provide consumers with both protection and information and l to provide the necessary public controls to ensure enforcement of a, b and c. Concerning the technical aspects, the Commission does not intend to prescribe methods of analysis for laboratories engaged in public control,