France’s Metrology network

A FORCE FOR PROgRESS

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ContentsFocus on international cooperation p. 4

Focus on knowledge p. 6From electrical metrology to quantum metrologyA dematerialized unit of massInto the future – time and frequency referencesTowards a new definition of the kelvin

Focus on innovation p. 8Galileo: a major EU projectReliable measurement up to 3 000 °CWhen metrology thinks big…Better characterisation of materialsMore accurate measurement of rotation and acceleration

Focus on performance p. 10LEDs show their true coloursTight control of refrigerant gas leaksReferences on a nanometric scaleImproving control of medical radionuclidesMicro and nanosystems for industry and research

Focus on health p. 12More precise radiotherapy for more effective treatmentQuantifying Legionella more accuratelyMore reliable diagnosis of chronic renal failureAnalysing breath and biomarkersExploring the structural properties of molecules

Focus on sustainability p. 14Aquaref, a reference laboratory for water monitoring Respecting electromagnetic field thresholdsDeveloping reference methods to determine pesticidesGuaranteeing interior air qualityControlling supervision of nuclear sites

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Measurement is an integral part of human activity, whether for scientific or economic purposes or in the general social interest. For it to be as useful as possible, metrologists must keep a constant eye on their changing environment. Scientific developments, new technologies and new regulations all create a growing need for accuracy and the continual expansion of our metrological knowledge.

Only a sustained commitment to research and development can ensure methods, instruments and standards evolve to keep pace with today's challenges. This is the key priority of France's metrology network. Comprising a dozen reference laboratories coordinated by the Laboratoire National de Métrologie et d’Essais (LNE), the network encompasses a wide range of complementary competencies that are recognized at international level, particularly in the context of the European Metrology Research Programme (EMRP).

The network's researchers are continually rising to new challenges in priority fields such as clinical medicine, nanotechnologies, environmental protection and space navigation. Not only will their innovations help manufacturers to integrate new technologies, on a wider level they will also provide a vector of security for society.

Working together, our metrologists are increasing our understanding of the world and enabling us to push back our frontiers. They are providing us with reliable data on which we can base our rules and policies, and helping society to build its future.

Luc Erard / Research and Development Director, LNE (until July 2010)

MaguELonnE cHaMBon / Research and Development Director, LNE (from July 2010)

PiErrE guiLLon / Chairman of Metrology Committee

ditorial / Working together For a Changing World

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Coometeuro-asian Cooperation of

national Metrological institutions

Eurameteuropean association of

national Metrology institutes

APMPasia Pacific

Metrology Programme

Afrimetsintra-africa

Metrology system

SIMinter-american

Metrology system

The Metre Convention of 1875 is a treaty which established the International Bureau of Weights and Measures (BIPM), an intergovernmental organisation under the authority of the General Conference on Weights and Measures (CGPM) and supervised by the International Committee for Weights and Measures (CIPM). Many countries subsequently set up their own metrology systems, producing the standard measures that are essential to everyday life. The national metrology network in France comprises four metrology laboratories run by the Conservatoire National des Arts et Métiers (CNAM), the Commissariat à l'Énergie Atomique (CEA), the Observatoire de Paris and LNE, along with six LNE designated institutes. This network has been coordinated by LNE since 2005.

Objective: accuracyThe French metrology network is supported by a Metrology Committee, made up of leading figures in science and industry and representatives of the Ministries of Industry and Research. The Committee identifies priorities and proposes long-term strategy. It is assisted by several scientific councils and by LNE's research and development department (DRST), particularly for project evaluation and coordination.The main task of the French metrology network is to create or improve units of the international SI system to the highest possible degree of accuracy, by producing and improving reference and transfer standards, and by developing reference resources and methods for all quantities. This will enable all parties concerned to access the metrological references they need.Work carried out within the network is validated by

means of inter-laboratory comparisons, either at European level (through EURAMET) or at international level (through the CIPM). Such comparisons are essential, both to promote the research performed and to establish confidence with foreign metrology laboratories, the various economic players and the bodies responsible for regulations.

Shared research, shared challengesFaced with globalisation of trade, increasingly complex technologies and new societal needs, metrologists worldwide felt it necessary to organise themselves across much larger geographic areas than their own country. During the 1980s and 1990s, national metrology institutes joined together in regional metrology organisations (RMOs) - see opposite. Countries that were not signatories of the Metre Convention could also join these associations.RMOs have several functions. They organise inter-laboratory comparisons, facilitate traceability across a geographic region, optimise technically advanced instrumentation, and promote scientific collaboration, development of metrological infrastructures and training.EURAMET, the European RMO grouping together laboratories in 34 countries, recently developed a common European Metrology Research Programme (EMRP) with the aim of obtaining funding from the European Union.In July 2009 the European Commission adopted Article 169/EMRP, under which the EMRP programme will receive e400 million of financing over a seven-year period.

IN A CONTExT MARkED By ThE EMERGENCE OF GROUND-BREAkING TEChNOLOGIES, ChANGING SOCIAL CONDITIONS

AND BURGEONING INTERNATIONAL TRADE, METROLOGy MUST PROvIDE hIGhLy ACCURATE RESULTS FOR OPTIMUM

MEASUREMENT TRACEABILITy IN ALL FIELDS. SCIENTISTS ARE INCREASINGLy CARRyING OUT ThEIR RESEARCh WITh

PARTNERS IN OThER COUNTRIES, PARTICULARLy ACROSS EUROPE, AND FRENCh METROLOGISTS hAvE NOT BEEN

SLOW IN ADOPTING AN INTERNATIONAL APPROACh.

FoCus on international CooPeration

the FrenCh netWork in Figures

the Metre Convention: ensuring traCeability at international levelIn 1960 the system of units established under the Metre Convention was renamed the International System of Units, the SI. It is currently based on seven units of measurement. Each unit may be represented by a reference standard, which is then reproduced as a primary, secondary or working standard.In order to supply society and industry with reliable quantitative information on the services provided by metrology laboratories, the CIPM operates a Mutual Recognition Arrangement (CIPM-MRA) for calibration and measurement certificates. Signed by 72 states (including France in 1999) and two international organisations, the MRA supplements agreements between accreditation bodies and provides a technical guarantee of measurement traceability.

/ LNE (laboratoire national de Métrologie et d’essais)Fields: chemistry and biology, dimensional metrology, electricity and

magnetism, mass and related quantities, mathematics and statistics

for metrology, nanometrology, optical radiation, temperature and

thermal quantities

/ LNE-INM/CNAM (institut national de Métrologie / Conservatoire national des arts et métiers)Fields: length, mass, optical radiation, temperature

/ LNE-LNHB/CEA (laboratoire national henri becquerel / Commissariat à l’énergie atomique)Field: ionising radiation (activity and dosimetry)

/ LNE-SYRTE/OP (systèmes de référence temps-espace / observatoire de Paris)Fields: time, frequency, gravimetry

six designated laboratories for specific fields:LNE-ENSAM (dynamic pressure), LNE-IRSN (neutron dosimetry),

LNE-CETIAT (hygrometry, liquid flow measurement, anemometry),

LNE-LTFB (time-frequency), LNE-LADG (gas flow measurement),

LNE-TRAPIL (hydrocarbon flow measurement).

Four national Metrology laboratories

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• •230 researchers

150 calibrationengineers and technicians

100+ scientific publicationsand 200+ papers each year on research projects

Annual budget of around30 million euros(provided by French government and European contracts)

3rd largest metrology network in Europe

Around 50 partnershipseach year with equivalent European laboratories, French university laboratories and laboratories of the National Scientific Research Centre (CNRS)

200 currentresearch projects

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FoCuson knoWledgekEy DISCOvERIES IN QUANTUM PhySICS, COUPLED WITh NEW TEChNOLOGIES, hAvE TRANSFORMED ThE SCOPE OF FUNDAMENTAL METROLOGy IN JUST A FEW DECADES. TO IMPROvE ThE CONSISTENCy OF ThE INTERNATIONAL SySTEM, METROLOGISTS NOW AIM TO LINk MEASUREMENT UNITS TO FUNDAMENTAL CONSTANTS, By DEMATERIALISING ThEM AND GIvING ThEM STABLE DEFINITIONS.

Part of the metrological triangle team. L. to r.: Olivier Seron, Nicolas Feltin, Wilfrid Poirier and Laurent Devoille.

scope of metrological triangle projectFor the last three years LNE has been working on the metrological triangle experiment, which consists in verifying the consistency of the three constants involved in the quantum phenomena studied in fundamental electrical metrology. These are the Josephson and quantum hall effects (already used for conservation of the volt and the ohm respectively), and the single-electron tunnel effect (studied to develop an ampere reference standard). Launched in the context of an overhaul of the International System of Units, the experiment should make a significant contribution to redefining electrical units from the fundamental constants h and e. The French institutions involved in this project include the CNRS Photonics and Nanostructure Laboratory and CEA-Grenoble for production of samples, and the CEA-Saclay Quantronics Research Group for scientific support.

initial resultsIn 2008 the researchers achieved a relative uncertainty of 4∙10-6 on measurement of the current delivered by a metal-based electron pump.

PerspectivesThe next short-term objective is to achieve a relative uncertainty of 1∙10-6, which means working with devices that can deliver stronger currents than those currently reached (maximum 16 pA). This is the subject of a joint project launched with the national metrology laboratories of Germany (PTB) and Finland (MIkES), which should result in the production of new samples. The project partners aim to reach a final uncertainty of 10-8.

scope of the watt balance projectThe kilogram is defined by an international prototype kept by the BIPM. The amount of substance forming this standard varies over time, however, mainly because its surface interacts with the environment. This situation is all the more serious as numerous quantities – including all electrical quantities – depend on the kilogram. An alternative solution consists in linking the unit of mass to a fundamental physical constant (the Planck constant) and determining its value as accurately as possible. The value of the constant can then be fixed and used as the basis for a new definition of the kilogram. Once it has been validated by the CGPM, all laboratories can then produce their own reference kilogram.

Method developedSince 2002, LNE, LNE-INM, LNE-SyRTE and several French and foreign partners have been developing a research project on the watt

balance. This electro-mechanical device relies on the two effects used in electrical metrology to characterise voltage and resistance: the Josephson effect and the quantum hall effect. By comparing virtual electrical and mechanical powers, it will be possible to link the kilogram to the Planck constant.

PerspectivesThe watt balance project is an integral part of the European e-MASS project run by LNE. An operational device should be available by 2011. The next stage, to be determined at a CGPM meeting in 2015, will depend on results obtained from different watt balance experiments carried out around the world.

Part of the watt balance team. L. to r.: Franck Bielsa, François Villar and Gérard Genevès.

ProjeCts

PersPeCtivesThe future clearly lies in quantum metrology, which is entirely different from the fundamental metrology we know today. But there is still a long way to go. For each unit, researchers working on this transformation will have to compare results and develop common strategies to obtain the most accurate measurements and the lowest uncertainties. By resulting in improved measurements and hence improved calibration chain performance, their work will clearly benefit manufacturers. But new instruments must be developed to transfer measurements to industry – in highly specialised fields such as space and nanotechnologies – and to society.

initial resultsAfter demonstrating the feasibility of a high-precision optical clock using cold atoms confined in a laser trap, the researchers have specified its operating conditions. They have also achieved a preliminary frequency accuracy of 2∙10-15.

PerspectivesThe next objective is to reach a measurement resolution in the 10-17 range, then to assess the clock at this level of performance. Since 2005, LNE-SyRTE has also been developing an optical clock using mercury atoms. Results obtained to date include demonstration of laser cooling of the mercury atom, and observation and frequency measurement of clock transition. The next step is to minimise the Doppler effect – one of the main limitations affecting the performance of microwave atomic clocks – by confining the atoms in a laser trap.

the oCs project – optical clocks for a new definition of the secondMicrowave atomic clocks are reaching their performance limits, with accuracy approaching 10-16, but optical frequency clocks are set to take over from them. Most of the limitations of optical clocks are independent, in absolute values, of transition frequency. As optical frequencies are 104 to 105 times higher than the microwave frequencies used by atomic clocks, the relative impact of their limitations is considerably reduced. A second perspective opened up by the development of optical clocks is the possibility of testing fundamental constant stability more accurately. To meet these challenges, LNE-SyRTE has been working since 2008 with PTB (Germany), INRiM (Italy), NPL (Uk) and MIkES (Finland) on a joint research project for an optical clock using strontium atoms.

Part of the OCS project team. L. to r.: Jérôme Lodewyck, Philip Westergaard and Pierre Lemonde.

scope of kelvin projectMetrologists worldwide are seeking to define the kelvin from a fundamental constant with a fixed numerical value. This is the Boltzmann constant (k), related to the quantum of thermal agitation energy kT, where T is thermodynamic temperature.

Methods developedThe project run by LNE-INM relies on acoustic measurement. The value of k is deduced by measuring the speed of sound in a noble gas in a closed cavity. LNE-INM has made fundamental improvements to the method normally applied, such as the use of gaseous helium – whose thermophysical properties are better known than those of gaseous argon – and determination of volume by microwave resonance.

Other methods currently being studied in French and European laboratories include the spectroscopic method (the value of k can be deduced by measuring Doppler broadening of an optical molecular resonance in thermodynamic equilibrium), or the method for the determination of the dielectric constant of a gas.

PerspectivesStudies performed by LNE-INM on prototypes have yielded promising results. The objective is now to improve uncertainty affecting the determination of k and achieve a relative uncertainty level in the region of 10-6 by the end of 2010.

Part of the Boltzmann constant team. L. to r.: Laurent Pitre, Fernando Sparasci and Daniel Truong.

FroM eleCtriCal Metrology to QuantuM Metrology

a deMaterialiZed unit oF Mass

into the Future – tiMe and FreQuenCy reFerenCes

toWards a neW deFinition oF the kelvin

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INTEGRATING NEW TEChNOLOGIES AND PROCESSES IS A CONSTANT PRIORITy FOR LEADING INDUSTRIES. IN ThIS CONTExT, IT IS ESSENTIAL TO ENSURE ThAT MEASUREMENTS ARE ACCURATE AND RELIABLE. ThE FRENCh METROLOGy NETWORk CONSTANTLy ANTICIPATES ThIS ChALLENGE, PARTICULARLy IN ITS RESEARCh INTO OPTICAL ATOMIC CLOCkS AND vERy hIGh TEMPERATURES.

FoCuson innovation

In the context of the development of the Galileo satellite navigation system, LNE-SYRTE is contributing to a project on the metrology of external time services. Interview with research engineer and project leader Pierre Uhrich.

What does the galileo project entail?The Galileo programme will provide Europe with its own satellite radio-navigation system, wholly independent of the American GPS system. Time-frequency metrology is crucial to the operation of such a system. For this reason a consortium of private companies and European national metrology institutes – including LNE-SyRTE – has been asked to produce the prototype of an external supplier of time metrology services, called the Galileo Time Service Provider (GTSP). Its essential role is to provide steering corrections so that the Galileo reference timescale will follow the international civil time scale UTC, modulo 1 second.

What has been accomplished so far?The GTSP prototype was developed with contributions from all the consortium members and installed at the French National Space Research Centre (CNES) in Toulouse in February 2009. Once the first signals were emitted, its evaluation began. The four laboratories involved in the project supply their clock comparison data on a daily basis. It will be used to compute the UTC prediction from which the Galileo timescale steering

parameters will be calculated. This data was previously sent to the BIPM only once a month. To cope with the new daily rhythm we have set up automatic generation, validation and transfer procedures, which should ensure similar high-quality results.

What special expertise has been needed for this project?We use two methods to compare the clocks of GTSP stations. The two way satellite time and frequency transfer method comprises emission and reception of bi-directional signals to and from telecommunication satellites. The other method is based on reception of GPS signals, with a maximum uncertainty objective of 5 ns to 1 σ. This means we must take into account signal propagation delays in the instrumentation, so we need to calibrate the various connections. In 2008 LNE-SyRTE carried out a GPS measurement programme that yielded very satisfactory results: the uncertainty obtained on GPS comparisons is 3.2 ns to 1 σ. Once the GTSP prototype has been validated, the next stage will consist in integrating specific Galileo data in the process.n

galileo: a Major eu ProjeCt

other ProjeCts

Reliable measurement up to 3 000 °CThe nuclear, arms and aeronautics industries, among others, require higher and higher temperatures for developing new materials or recycling. Precise knowledge of very high temperatures is needed to ensure the quality of materials and limit energy loss. LNE and the CNAM have joined forces to develop new fixed points and thus improve uncertainty on the highest part of the temperature scale (1 000 °C to 3 000 °C) by a factor of 2 to 5. The ultimate objective is to transfer these new references to industry.

Better characterisation of materialsknowledge of the thermo-physical properties of materials is essential for many sectors of industry. It is particularly necessary for increasing energy saving in buildings, improving the efficiency of vehicles and thermal power plants, and facing the challenges set by nanotechnologies. To meet these different needs, LNE is developing metrological installations to measure the thermal diffusivity, conductivity and radiative properties of all types of materials (metals, ceramics, thin layers, composites, etc.) in temperatures up to 1 400 °C.

Part oF the galileo teaM.L. to r.: Pierre Uhrich, Joseph Achkar and Philip Tuckey.

PersPeCtivesThe research being carried out by the French metrology network will lead to improvements in numerous industrial applications. one example is galileo, the satellite navigation system whose future benefits will include earthquake prediction and safer aircraft landing.But metrologists are already preparing the next stage. LnE-SYrTE, for example, is working on the PHarao clock, in the context of the Eu project for an atomic clock Ensemble in Space (acES). This clock uses caesium atoms which are laser cooled to under a microkelvin, resulting in greater frequency stability and accuracy than ever before. From 2013 several of these new-generation clocks will be installed in the international space station and compared with terrestrial clocks.on a wider level, the signals emitted by acES clocks will enable us to test Einstein's general theory of relativity to a remarkable degree of accuracy… and possibly to identify hitherto unknown forces.

When metrology thinks big…Sectors such as aeronautics and geology rely on dimensional parameters whose traceability to the metre is not totally satisfactory. LNE-INM is contributing to the EU Long Distance project – launched to provide highly accurate distance measurements – by developing a superheterodyne interferometer using the notion of synthetic wavelength. This will enable it to obtain wavelengths of around one centimetre, making it easier to determine interference levels and providing measurement uncertainty of around 10 µm. LNE-INM is also developing various spectroscopic methods to measure the air index over large distances.

More accurate measurement of rotation and accelerationAtomic interferometry is used to produce state-of-the-art inertial sensors (rate gyros and gravimeters). To improve performance even further, LNE-SyRTE is developing a highly sensitive and accurate rate gyro, which will significantly increase the operating range of interferometers. This could be a major step forward concerning the use of atomic inertial sensors in environments that are less well protected from extraneous vibrations than laboratories, especially in the fields of geology, crude oil exploration and air navigation.

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Project launched: June 2005Laboratories involved:LNE-SYRTE (France), PTB (Germany), INRiM (Italy), NPL (UK)Discipline concerned:metrology of time and frequencySchedule: GTSP prototype validation 2009; Galileo system launch planned for 2014

Project in brief

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a Part oF the led ProjeCt teaM.L. to r.: Bernard Rougié, Gaël Obein, Annick Razet and Nicolas Pousset.

FoCuson PerForManCeNANOSCIENCE AND NANOTEChNOLOGIES – FAST-ExPANDING SECTORS – REPRESENT A kEy STRATEGIC RESEARCh FIELD FOR ThE FRENCh METROLOGy NETWORk. ThE MAIN OBJECTIvE IS TO PROMOTE DEvELOPMENT IN INDUSTRy, BUT IN A WIDER SOCIAL AND ECONOMIC CONTExT IT IS FOCUSING ON SPECIFIC AREAS LINkED TO CONSUMER DEMAND, SUCh AS LEDS AND REFRIGERATING EQUIPMENT.

leds shoW their true Colours

other ProjeCts

To characterise the capacity of white light-emitting diodes (LEDs) to render colours, LNE-INM is developing a specific indicator using the metrology of appearance. Interview with CNAM professor and project leader Annick Razet.

What does the led project entail?The lighting sector is going through sweeping changes. Faced with the need to promote energy saving in the context of sustainable development, high-power white light-emitting diodes (over 1W) will be replacing conventional incandescent light sources. Before these new LEDs go into production, a serie of measurements must be made to determine the quality and quantity of the optical radiation emitted.

What has been accomplished so far?LNE-INM is characterising LEDs through metrology of appearance, i.e. by analysing the quality of the light emitted. The aim is to develop a specific colour rendering indicator to advance market standards. Our approach involves developing instruments and methods to measure physical quantities for LEDs – spectral distribution – and correlate them with visual measurements of colour samples. The first stage has consisted in performing colorimetric analysis of lighting systems emitting white light. To do this, we used a device consisting of a grating spectroradiometer and a light booth

reproducing the experimental conditions of visual measurement. We have already considerably expanded our knowledge of the colorimetric parameters of LEDs – chromatic coordinates, colour temperature and colour rendering indices.

What is the next stage?We have assembled a group of volunteers to carry out visual measurements of colour samples in different lighting conditions. This study is currently being performed. When it is completed the results will be correlated with the colorimetric parameters we have already obtained to finalise the new colour rendering indicator.n

Project launched: 2007Laboratories involved:LNE-INM, Natural History Museum (MNHN)Disciplines concerned:optical radiation, metrology of appearanceSchedule: project completion in 2010, possible extension with a study of the energy component in the frame for an EU project

Tight control of refrigerant gas leaksRefrigerating equipment containing greenhouse gases must now undergo periodic leak tightness controls, using a leak detector with a sensitivity lower than 5 g/yr (measured according to standard EN 14624). To help companies meet this new requirement, LNE has developed a method of leak rate measurement based on infrared absorption. Enabling it to design, produce and qualify a complete calibration chain for calibrated leak rate measurement of R-134a (1 g/yr to 50 g/yr) through to estimation of the sensitivity threshold of manual detectors (specified in EN 14624).

Improving control of medical radionuclidesThe scope of nuclear medicine has increased considerably over the last few years, but the radiopharmaceutical industry cannot use new radionuclides until they are accurately characterised. LNE-LNhB has begun studying a selection of radio-nuclides that are considered the most useful. The aim is to create primary references in terms of activity and methods of transfer to users, and to measure data to learn how the radio-nuclides disintegrate. LNE-LNhB is also contributing to an international traceability programme.

Project in brief

PersPeCtivesresearch in nanometrology will lead to applications in three key fields.in the electronics industry, smaller and smaller electronic devices are being produced. High-precision on-line measurement at nanometric scale is required to control reproducibility of manufacturing processes. it is therefore essential to ensure traceability for scanning probe microscopy and X-ray diffraction instruments.a second field is r&d, where new instruments must be developed to study the properties of small-scale materials. instrumentation depends on accurate standards, so new reference materials must be produced. This is particularly the case in spintronics, where spin flips are used to increase storage capacity and reference magnetic materials can be used to improve existing devices.Thirdly, nanometric precision is also required in the ecological field, to detect materials contained in gaseous or liquid matrices.

References on a nanometric scaleMetrology on a nanometric scale involves a wide range of quantities and fields of expertise. LNE has chosen to focus on three spheres: granulometric measurement of aerosol nanoparticles, small-scale magnetic measurement, and dimensional measurement of structured objects. This work will enable manufacturers to link their instruments to the SI system. Industries such as electronics or cosmetics will benefit from improved measurement traceability, and hence better control of their manufacturing processes, and the effects of nanoparticles on health will also be assessed more accurately.

Micro and nanosystems for industry and researchInnovative new technologies, based on silicon-substrate nano and micro-electro-mechanical systems, or MEMS, are revolutionising all sectors of industry, from medical products to automobiles or telecommunications. In metrology, MEMS will make it possible to produce alternating voltage references up to 100 Mhz. key applications will include new high-precision miniaturised instrumentation such as voltage micro-generators.

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Part oF the ebCt and 3d braChytheraPy teaMs.L. to r.: Jean-Marc Bordy, Dominique Cutarella, Johan Plagnard and Isabelle Aubineau-Lanièce.

More PreCise radiotheraPy For More eFFeCtive treatMent

other ProjeCts

PROGRESS IN MEDICINE, COMBINED WITh RIGOROUS PUBLIC hEALTh POLICIES, IS EFFECTIvE ONLy IF IT IS SUPPORTED By INSTRUMENTS ThAT ARE RELIABLE AND CAN BE MANUFACTURED ON AN INDUSTRIAL SCALE. ThE CORNERSTONE OF ThIS ChALLENGE IS ACCURATE MEASUREMENT – ThE BASIS FOR NUMEROUS ADvANCES ThAT WILL FAvOUR MEDICAL TEChNOLOGIES PRESENTING LOWER PATIENT RISk AND LEAD TO MORE EFFECTIvE PREvENTION.

FoCuson health

Radiotherapy is now a high-technology discipline based on complex systems. To ensure stricter metrological control of these systems, two EU projects have been launched: EBCT (External Beam Cancer Therapy) and 3D Brachytherapy. LNE-LNHB is a key contributor. Interview with François Damoy, head of LNE-LNHB.

Why were the ebCt and 3d brachytherapy projects set up?Many therapeutic improvements have been made in the fight against cancer, such as intensity modulated conformal radiotherapy, tomotherapy installations, and the Cyberknife. These innovations increase a patient's chances of survival by irradiating the tumour more precisely and limiting the exposure of surrounding healthy tissue. But they are so complex that they tend to dissociate the metrological references for absorbed dose from the doses actually delivered. To guarantee the quality of our health services, it is essential to define reference conditions that are closer to the actual conditions.

What has been accomplished so far?As far as external radiotherapy is concerned, our studies have shown that the present references – established on the basis of a 10 x 10 cm² radiation field – are valid for a field as small as 4 x 4 cm². Research on smaller scale fields continues, but the lower limit for primary measurements should be around 2 x 2 cm². For brachytherapy – which consists in placing a radiation source inside

the patient's body – the difference between reference conditions and actual conditions of use can be reduced only by using dosimeters that offer higher performance in terms of stability and reproducibility.

What are the future prospects?New absolute detectors are being produced for primary measurement on fields of around 2 x 2 cm². But we can already foresee using millimetric relative dosimeters, which will enable us to deliver irradiation that corresponds more closely – within about half a centimetre – to the size of the tumour. They will also make it possible to map the doses applied in 2D or even 3D. From now on, LNE-LNhB will be contributing to a large-scale project called DOSEO, which brings together the different institutions concerned to develop the radiotherapy systems of tomorrow.n

Project launched: April 2008 for EBCT, July 2008 for 3D BrachytherapyLaboratories involved: more than ten European national metrology institutesDiscipline concerned: physics of radiationSchedule: projects to be completed in 2011, implementation of DOSEO platform by end of 2011

Project in brief

More reliable diagnosis of chronic renal failureAn estimated two to three million patients in France suffer from chronic renal failure. A biomarker called creatinine is used to diagnose this disease. To ensure fast screening and limit public health expenditure, reliable results are essential. LNE is addressing this concern by developing a reference method based on isotopic dilution used with gas chromatography-mass spectrometry. The method will be used to assess the quality of routine analyses performed by medical laboratories.

Quantifying Legionella more accuratelyMolecular biologists are able to detect and quantify Legionella DNA by using the polymerase chain reaction method (PCR). To calibrate this type of analysis, the French scientific community is developing a genomic DNA primary standard. LNE is working on characterising the quantity of DNA in the standard by developing an ICP mass spectrometry measurement method based on quantification of phosphorus. This research will also cover defining related uncertainties and linking the standard to the International System of Units.

Analysing breath and biomarkersPhysico-chemical analysis of breath can be a highly effective technique for early diagnosis of certain pathologies (cancers, bronchopulmonary and gastric affections), but its possibilities are limited by a lack of accurate and easily usable instruments. Working within a European consortium, LNE-INM is seeking to develop an appropriate tool using an optical detection technique based on laser absorption spectroscopy of the molecular compounds in breath. This technique will offer considerable advantages, notably high detection sensitivity (below 1 ppb, equivalent to the sensitivity of a dog's nose) and real-time diagnosis.

Exploring the structural properties of moleculesAfter developing an interferometry technique to characterise macroscopic components used in optical fibre telecommunications, LNE is now applying this method to microscopic components for the health and environment sectors. Its researchers are also working on developing photonic sensors (functionalised optofluidic microresonators). They hope to produce a device capable of analysing chemical molecules (heavy metals present in water) or biological molecules (DNA) on a far smaller scale than was previously possible, and observe changes in their conformation.

PersPeCtivesin the medical field, the more we learn about dosage and the interaction between medical instruments and the human body, the more accurate the diagnoses and biological or medical analysis we can provide. This is a key challenge for the French metrology network. By elaborating new methods, metrologists will help to develop new treatments such as gene therapy and hadrontherapy (radiotherapy using protons), to early detection of diseases and hence to prevention.While it is too early to quantify the benefits to public health, it is clear that improved measurement has a direct impact on the individual, through its contribution to effective prevention and more appropriate treatment and medication. There is also a clear economic benefit, since inadequate, inappropriate or ineffective treatment represents appreciable costs.

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Part oF the aQuareF teaM.L. to r.: Julie Cabillic, Sophie Lardy-Fontan and Véronique Le Diouron.

aQuareF, a reFerenCe laboratory For Water Monitoring

other ProjeCts

PersPeCtivesThe metrology programme for the next few years covers several angles of research. The main aim will be to develop analytical methods that are both more effective (particularly in identifying new pollutants) and easier and faster to apply. Quality control tools – standards and reference materials – must also be improved.apart from environmental quality monitoring, metrology will also play a key role in the treatment of specific environments (water and air pollution control, etc.), as the efficacy of this type of operation can be demonstrated only on the basis of reliable analytical data.another fundamental objective is improving the reliability of scenarios modelling the impact of climate change on the environment. This means producing and verifying new data that can be fed into the numerical models used by forecasters.

IN RESPONSE TO GROWING DEMAND FROM ThE AUThORITIES, INDUSTRy AND ThE PUBLIC, SEvERAL PROJECTS hAvE BEEN LAUNChED TO IMPROvE ThE QUALITy OF ENvIRONMENTAL MONITORING By STRENGThENING ThE METROLOGICAL FRAMEWORk OF ENvIRONMENTAL ANALySIS. ThE MAIN OBJECTIvE: IMPROvING COMPARABILITy AND TRACEABILITy OF MEASUREMENTS.

FoCuson sustainability

In response to stricter requirements concerning aquatic environments, metrologists are working on new references in the chemical field. Interview with Sophie Vaslin-Reimann, head of LNE's Metrology, Chemistry and Biology pole.

Launched: 2007Laboratories involved: BRGM, Cemagref, Ifremer, Ineris, LNEDisciplines concerned: chemistry, hydrobiologySchedule: revision of national Water Management Plan (SDAGE), list of priority substances and inventory before 2015

Chemical metrology is a relatively new discipline. What is being done to ensure its contribution is recognised?The CIPM committee that deals specifically with chemical metrology – the Consultative Committee for Amount of Substance (CCQM) – was set up only in 1993. Since then, however, spiralling concern over environmental and consumer protection has pushed questions of water and air quality to the forefront of public concerns, resulting in an arsenal of new regulations. This context favours the development of chemical metrology, of course. Our priority today is to validate methods and reference materials that guarantee the reliability, comparability and reproducibility of measurements, and to make them available to analysis laboratories.

lne is a contributor to aquaref. What is the role of this laboratory?The European Water Framework Directive was adopted in 2000 to establish EU policy in this field. It requires Member States to ensure their natural water resources – rivers, lakes, coastlines, etc. – are in a satisfactory ecological and chemical state by 2015.

Aquaref is the French reference laboratory for monitoring aquatic environments. Set up in 2007, it draws on the expertise and research capabilities of several institutions in the hydrobiology and water chemistry fields. Its purpose is to help the French authorities apply the Directive by developing methods to identify the substances concerned (sediments, biota, silt, etc.), developing a methodology for bioindicators, and drawing up requirements for scientific and technical monitoring operations.

What has been achieved since 2007?Aquaref has been integrated in the National Water Data Plan (SNDE) to help the authorities develop codification systems for this data. Moreover, dialogue is well established with the various aquatic environment monitoring bodies: a website has been created and thematic seminars are held every six months. The scene is now set for real progress. Producing reliable measurements will require concerted action, especially as new risks emerge.n

Developing reference methods to determine pesticidesTo control environmental matrices (water, sediments) and agri-food matrices (cereals and derived products), LNE is developing the primary method of pesticide analysis by isotopic dilution combined with liquid chromatography-mass spectrometry. Following the completion of a doctoral thesis on this subject, the Laboratory has already validated an analytical method for determining 38 pesticides belonging to 26 chemical families. LNE has also worked with a university laboratory to develop a certified reference material for determining herbicides in water.

Respecting electromagnetic field thresholdsTo ensure that standards covering exposure of workers to electromagnetic fields are respected, it is essential to establish the traceability of specific absorption rate (SAR) measurements to national reference standards up to 10 Ghz. This is the subject of a European research project to which LNE is contributing. The main aim is to develop calibration benches for SAR measurement probes, along with benches for measuring the complex permittivity of reference liquids and tissue-equivalent liquids.

Guaranteeing interior air qualityInterior air quality is assessed by means of samplers which are analysed in the laboratory. To ensure accurate analysis results, LNE is currently developing new matrix reference materials. They must be as close as possible to the real samples and take the same form as the samplers used on site. The method used consists in doping the different compounds to be determined (vOCs, aldehydes, nitrogen dioxide, etc.) on specific samplers.

Controlling supervision of nuclear sitesTo measure the radiological state of the environment and the impact of nuclear facilities, laboratories must obtain prior approval from the French Institute of Radiation Protection and Nuclear Safety (IRSN). Approval is granted following mandatory tests. As the national metrology laboratory in the ionizing radiation field, LNE-LNhB is working with the IRSN on a programme of inter-laboratory tests preliminary to the mandatory tests. In this context, it is preparing environmental samples for different types of matrices (soil, plants, liquids, etc.).

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Project in brief

Laboratoire National de Métrologie et d’Essais (LNE)Research and Development Direction (DRST)

1 rue Gaston Boissier75724 Paris cedex 15 - France

Tel.: +33 1 40 43 37 00E-mail: research@lne.fr

Website: www.french-metrology.com

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