metrology in chemistry - braunschweig...

(1) Braunschweig, 23.05.13 © PTB2010

…from physics…

…to chemistry!

Metrology in chemistry concepts, structure,strategies, priorities

Metrology...


Aus deutschen Landen frisch auf den Tisch

...

...

...

Quality assurance for chemical measurements


...

...

...

Quality assurance for chemical measurements

Motivation:

• Life and well-being as well as international trade require inter-

tionally comparable measurements in chemistry on a high level

• Analytical measurements cannot be carried out by normal people (the

taxpayer) – a globally accepted infrastructure is required that provides

globally accepted comparability of analytical measurement results

• Similar quality standards must apply für chemical measurements on a

global scale with respect to traceability, measurement uncertainty and

detection/quantification limits

Motivation:

• Life and well-being as well as international trade require inter-

tionally comparable measurements in chemistry on a high level

• Analytical measurements cannot be carried out by normal people (the

taxpayer) – a globally accepted infrastructure is required that provides

globally accepted comparability of analytical measurement results

• Similar quality standards must apply für chemical measurements on a

global scale with respect to traceability, measurement uncertainty and

detection/quantification limits


I. Metrology in Chemistry - what it means & why we need it?

II. How is chemistry integrated into the SI

- Chemistry and Meter Convention

III. How does it work ? - global traceability structures in chemistry an application case IV. Traceable …to what ?

- Reference methods in chemistry….and there future!

V. How to build up international metrological infrastructures?

...in chemistry

Overview


metrological traceability

property of a measurement result whereby it can be related

to a reference through a documented unbroken chain of

calibrations each contributing to the measurement uncertainty

International Vocabulary of Basic and General Terms in Metrology (VIM):JCGM 2008

what is traceability?

NOTE 2 The expression “traceability to the SI“ means

metrological traceability to a measurement unit of the

International System of Units

NOTE 1 For this definiton a “reference” can be a

definition of a measurement unit through its

practical realization, or a measurement procedure,..

to a measurement unit

to the SI ?


SI base unit "mole" (the "chemical" base unit)

• Definition:

1. The unit mole is the amount of substance

which contains as many elementary entities

as there are atoms in 0.012 kilogram of

carbon 12; its symbol is “mol”.

2. When the mole is used, the elementary

entities must be specified and may be

atoms, molecules, ions, electrons, other

particles, or specified groups of such

particles.

• Year of Definition: 1967

• Problem: in practise, a realization for all

measurands (analytes in a matrix) is required (amount-of-substance concentration)

• Solution: primary standards for substances of priority

Si-sphere for the re-determination

of the Avogadro number NA


• 1967 Introduction of the mole as the 7th "chemical" SI-base unit • 1993 Foundation of the "Consultative Committee for the Amount of Substance" – CCQM as part of the Meter Convention • 1999 Signing of the CIPM-MRA (mutual recognition of National Standards)

• since 2003 Cooperation of CCQM with several international organisations

Metrology in Cemistry: Historical overview


Consultative Committee for Amount of Substance –

CCQM - Metrology in Chemistry (est. 1993)

aim

to establish

• - worldwide comparability of measurement results in chemistry

• - traceability to the SI, whenever possible, or other internationally accepted reference points

• development of primary standards (methods & reference materials) and data bases

• validation of the traceability of measurement methods

the route

• cooperation with all important stakeholders worldwide

• national and international comparisons

Consultative Committees: CCQM


Metrology in chemistry - international

Consultative Committee for Amount of Substance –

CCQM - Metrology in Chemistry

• Designation of national/regional testing reference laboratories,

acting as an NMI in their field of expertise - no duplication

• Having MoU’s with WMO, WHO, IFCC, ILAC

• Close cooperation with

– ILAC/IAF

– ISO

– Codex Alimentarius Commission

– Inter-Agency meeting

– Global Food Safety Initiative

– World Anti Doping Agency (WADA)



II. How is chemistry integrated into the SI?





...in chemistry

Overview


blood sample collected at a medical practitioner…

..and send to a clinical test laboratory..

…are the results reliable ?

…when are they available ?

…is the test expensive?


Problem...

…is the result true?

…what is the measurement uncertainty?

…would I get a different result from a different test laboratory?

…is it relevant?

“Your cholesterol level is too high,

the result from the test laboratory is

some 10 % above the normal level.”

well, ...he is

between

life and death... ..he can‘t

make up his mind

as always !!


100 200 300

100

200

Cholesterol, mg/dL

no

. o

f p

atie

nts

decision limit:

240 mg/dL

results of > 20.000 people

healthy cases (20%)

unnecesseraly treated

untreated (13%)

pathological cases

deviation +10 %

deviation -10 %

Mayo Clinic patients

data from: W. May (NIST) with kind permission

Consequences of inaccurate meas.: cholesterol


even small differences of results may have drastic consequences in clinical chemistry : • are the conclusions of statistical studies in part of the world applicable elsewhere? • do doctors in Germany, the US and elsewhere work on the same basis?

problems, questions...

results analytical measurements may have profound influence on

our daily living

they are the basis of national & international laws and regulations

they must be trustworthy and comparable on an international scale


legal framework in clinical chemistry...

legal requirements in laboratory medicine

• law on medical products and operator ordinance

• directive of the Federal Physicians Council for QA

• EU-IVD (in vitro diagnostic medical devices) directive 98/79/EC


directive of the Federal Medical Physicians Council in Germany (RiLiBÄK)

• measurement

frequency

• medical

relevance

list is continuously updated

selection criteria:

RMW- reference method value SW- setpoint value

priority analytes

analyte measured quantity type of result

max. deviation allowed

amount-of-substance or mass concentration


international units

measurands in human serum/plasma

uric acid

urea

human


medical testing laboratories (thousands)

within the quality assurance programme of the German health care system

medical testing laboratories (thousands)

within the quality assurance programme of the German health care system

PTB, DGKL

Primary standards and measurements

PTB, DGKL

Primary standards and measurements

Comparison measurements on “real life” samples

Accredited clinical calibration laboratories Accredited clinical calibration laboratories

(nominated as reference laboratories by the BÄK)

Test samples with traceable values for proficiency testing in the

framework of external quality assurance

+ accurate: calibration needed,multiplier

- expensive and time consuming

+ very accurate

- very expensive and time consuming

Comparison measurements for accreditation

- not so accurate

+ cheap, fast and reliable within legal requirements


framework of external quality assurance (4x/year)

…up to several thousand measurements per day !!!

isotope dilution mass spectrometry (IDMS) isotope dilution mass spectrometry (IDMS)

primary ratio method: ≈ ± 1 % (k=2)


primary & secondary methods: ≈ ± 5 % (k=2)

spectrophotometry, chromatographies (IC, HPLC, GC),

test kits: test kits: ≤ 13 % (k=2) (legal requirement for cholesterol)

test kits, immuno-assays, photometric methods


framework of external quality assurance

legal requirements in laboratory medicine


clinical chemistry: application case

black:

acceptance-limits of DGKL

based on

IDMS reference method

coloured squares:

method-dependant limits

blue:

Liebermann-Burchard method

green:

CHOD-PAP method

red:

CHOD-Iodide method

from: L. Siekmann

Proc. Meas.Trac.,Gaithersburg, Nov.2000

with kind permission

YOUDEN diagram

(round robin test of DGKL for cholesterol (1987)

±13

%


legal requirements: reference laboratories



primary & secondary methods: ≈ ±

test kits:

Cholesterol in serum

Reference laboratories

±5%

spectrophotometry

IDMS


legal requirements: Key comparisons of NMIs (CCQM)




primary & secondary methods: ≈ ± 5 % (k=2)

test kits:

test kits, immuno-assays, photometric methods

±1%








...in chemistry

Overview

(22) © PTB2010

metrology of time: national (primary) standard

second

• definition:

• The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.

• Year of definition: 1967

• measurement uncertainty (so far): 10-15 (0,03 µs/year)

• practical realisation: caesium -fountain clock

state-of-the-art caesium atom clock with laser-cooled atoms

CSF1


primary method of measurement

reference measurement procedure used to obtain

a measurement result without relation to a measurement

standard for a quantity of the same kind

...

NOTE 2 Definitions of two subordinate concepts, which

could be termed “direct primary reference measurement

procedure” and “ratio primary reference measurement

procedure”, are given by the CCQM (5th Meeting,1999).

International Vocabulary of Basic and General Terms in Metrology (VIM):JCGM 2008

what is a primary method ?


Realisation of National Standards in Chemistry

measured quantities in chemistry

• Analytical Chemistry:

measurement methods for the

determination of the

concentration of an analyte in a

matrix (ratio measurement)

• Electrochemistry:

measurement methods for the

determination of electro-

chemical quantities

(pH, electrolytical conductivity)


B D

ion source E

• ion source

– plasma-ionisation

• analyser

– double focussing

• detector

– simultaneous measurements

– Faraday-cups

– high precision

– medium sensitivity

MS example: MC-ICP-MS (Neptune)

condensor: discrimination

quadrupole: energy focussing

magnet: mass discrimination

m/z


ID-MS: primary ratio method

internal standard („spike“):

388.7 g/mol

13C

OH

Primary ratio method:

Isotope dilution mass spectrometry (isotopic labelling): ex. Cholesterol (idealised!)

analyte:

386.7 g/mol

OH

13C- Cholesterol

(known)

Serum

(1g)

13C-

Cholesterol

(known)

un

kn

ow

n


signal distribution for a nat. isotopic

substance containing 27 C- Atoms

(as cholesterol is)

labeled material with 2 C- atoms

replaced by 13C (assuming 95%

success)

l.m.

analyte


isotopic var. distr. over all atoms within molecule ex. cholesterol (more realistic)


isotopic var. distr. over all atoms within molecule ex. cholesterol (more realistic)

ID-MS: primary method for small molecules

A. Henrion


sample

solution reference

solution

m/z m/z

same amount

of l.m. added

same ratio of

signal intensities:

same amounts

of nat. material

amount analyte

in sample soln.

equals amount

in ref. soln.


Primary ratio method: practical procedure (exact matching) Primary ratio method: practical procedure (exact matching)

A. Henrion


Isotpe dilution mass spectrometry (ID-MS)

Calculation of the amount of substance na from the MS signal ratio R

na = nr (Rs – Rsr) (Rsp - Ra) / [(Rsr – Rsp) (Ra - Rs)]

a analyte

r reference

na amount of substance of analyte in sample solution

nr amount of substance of analyte in reference solution

Rs isotope signal ratio in sample and reference solution

Rsp isotope signal ratio in spike

Rsr isotope signal ratio in spiked reference solution

Ra isotope signal ratio in spiked sample solution

from: Andre Henrion, Fresenius J Anal Chem (1994) 350:657-658

ID-MS: primary ratio method



A. Henrion

(Key-) features of IDMS

reliability by the principle used

(internal standard method)

high selectivity by the combination

sample clean-up/ chromatography/

mass spectrometry

precision better than 3%, many cases <1%

best way to accuracy


The future: What is needed?

Major application fields for Metrology in Chemistry:

• Medicine

• Environment

• Food

• forensics

• fundamental metrology

Experimental challenges: traceability for....

• large molecules (biomolecules)

• element species

• trace analysis

• fast (point-of-care) testing methods

• on-line, in-line measurements


directive of the Federal Medical Physicians Council in Germany (RiLiBÄK)

• measurement

frequency

• medical

relevance

list is continuously updated

selection criteria:

RMW- reference method value SW- setpoint value

pregnancy hormone

priority analytes: complex biomolecules

analyte measured quantity type of result

max. deviation allowed



international units

measurands in human serum/plasma

uric acid

urea

human


principle:

Molecular recognition of proteins

(antigen) by immunoglobulins

(antibodies)

merit:

highly selective recognition of

molecules with a specific

„key“-epitope

limit:

vulnerable to cross

reactions

antigen

(target-

protein)

epitope 2

antibody

diff. antigen

(cross reac.)

epitope 1

testkits with different „keys“:

very different results possible

quantification of proteins by

immuno-assays

testkit

A

B

C

19,9

6,7

0,9

ng/ml

115

489

27

# labs.

from: G.S.Bodor, Denver Health and Hospitals (1997)

example: troponin

T2.J11: traceability for complex biomolecules


...from small to large molecules...

cholesterol (386.7g/mol)

C- reactive protein

(~ 125.000 g/mol)

Unique challenges encountered with proteins:

Proteins are macromolecules

Structural heterogeneity of proteins

LODs for the measurement of proteins

A. Henrion


ID-MS: problems with complex molecules

Angiotensin I (peptid hormone)

a. rel. mass resolution: 5000

b. rel. mass resolution: 1000

product of adrenal gland for controlling

the blood pressure

A

from:

U. Bahr und M. Karas: “Massenspektrometrie Tutorial“

Inst. f. Pharmazeutische Chemie, Universität Frankfurt

Monoisotopice mass 1296,68518

Average mass 1297,50248

a.

b.

12C62H90N17O14 12C61

13C1H90N17O14 12C60

13C2 H90N17O14 12C59

13C3H90N17 O14


hGH

T6

T12 T12*

T6*

isotopically labelled

reference materials

+

+

problem: spectral resolution not sufficient for large molecules

solution: Quantifying enzymatic fragments


A. Henrion


challenge:

Identifying und Quantifying of protein fragments by ID-MS

preconditions:

- identification of a characteristic protein fragment

- quantitative hydrolysis process

A. Henrion



fragments used:

Application to hGH solution

of known concentration

(synthetic solution)

+ 3 %

- 3 %

(PTB) (LGC)

comparison of

different fragments

from:

C. Arsene et al.

Anal. Chem. 2008, 80, 4154


A. Henrion


5

10

15

20

25

30

µg/L

A

B

kit 44 (Lumineszenz) kit 66 (Photometrie)

kit 36 (Radioimmuno-)

kit 77 (‘Lumineszenz’)

IDMS-

reference

value

Test kit data:

Referenzinstitut für

Bioanalytik,

dgkl-rfb.de

12.3±0.5

determination of

T6 und T12

3 aliquote/sample

(A and B)

u (repeatability): 2.5%

U~ 5%

First ID-MS results on 22k growth hormone:

comparison to commercial test kits

6.9±0.4 IDMS reference

value:

Arsene, Henrion et

al. Anal Biochem

401(2010)228

A. Henrion

C. Arsene

R. Ohlendorf

H. Cakar


A. Henrion


in Germany, traceability is required & provided for...

Total protein

Enzymes most relev. enzyme activities

Metabolites & substrates cholesterol, creatinine, glucose, uric

acid, urea, triglycerides, bilirubine,

lactate Hormones cortisol, progesterone, aldosterone,

estradiol, estriol, testosterone, thyroxine

Elements Li, Na, K, Mg, Ca, Cl

Drugs digoxin, digitoxin, theophylline

T2.J10 "Tracebioactivity"

categories: examples:


Traceable measurements for biospecies

and ion activity in clinical chemistry PTB (GER coord.), DFM (DAN), INRIM (ITA), LGC (UK),

LNE (FRA), METAS (SUI), Metrosert (EST), SMU (SK),

SP (SWE), UME (TUR)

Challenge:

From element concentration to clinical activity

Problem

Medical diagnostics requires more precise

information:

not only the total amount of an analyt must be

known but it’s clinically active form

Solution

Si-traceable standards for biospecies an

ion activites of relevant elements

T2.J10 "Tracebioactivity" - speciation analysis


Standards required:

biospecies: Anticancer role of Selenium

• Se-species like methylselenol (CH3SeH)

are highly effective chemopreventive

against cancer.

Increased Se levels in combination with

chemotherapy improve its efficacy in anti-

cancer treatment

• but: narrow window between essentiality

and toxicity

Accurate knowledge of the level of specific

Se-species in blood serum is decisive for

there therapeutic behaviour

> 1,0 µg/g: toxic

< 0,1 µg/g: deficient

e s s e n t i a l Se-species and cancer cell

T2.J10 "Tracebioactivity" - speciation analysis


T2.J10: Quantifying species in serum

Sample preparation

chromatographic

separation

detection

IC, GC, HPLC

M

ICP-MS

total content species

content

extraction decomposition

sample

ICP-MS

t

conv. elemental analysis species analysis

+ spike:

Isotopically labelled

internal reference

C. Swart (EMRP)

D. Schiel

O. Rienitz

C. Frank


IGSM: ID-SERS Raman-spectrometry

a primary method for metrology in chemistry based on Raman-

spectrometry

motivation:

only on primary method for chemical analysis:

mass spectrometry (ID-MS)

solution:

Raman-spectrometry (ID-SERS)

• different physical mechanism

• sensitive for mass

• molecule identification, structural information

problems: detection limit & measurement uncertainty


Raman spectrometer „LabRAM ARAMIS“


ID-SERS Spectrometry: ex. Creatinine

measurement range isotope effect

Ra

ma

n s

ca

tte

rin

g /a

.u.

Raman shift / cm-1

R. Stosch


surface enhanced Raman scattering (SERS)

metal-nanoparticels

(Ag/Au)-colloids

signal enhancement up to 106

R. Stosch


- 6

- 4

2

0

2

4

6

E D C B

rel. d

ev.

/

%

ID-MS

3%

ID-SERS

ID-SERS Spectrometry: ex. Creatinine

from:

Surface-enhanced Raman scattering based approach for

quantitative determination of creatinine in human serum

R. Stosch, A. Henrion, D. Schiel, B. Güttler

Anal. Chem. 2005, 77, 2386-7392

institute

Creatinine in human serum:

ID-MS and ID-SERS


ID-SERS on nanostructured „Chips“


periodical Gold-nanoarrays

50 nm

Au-triangel-structure (SEM) FDTD-Simulations

gap size between particels 10 nm

structure optimisation by numerical simulation

5 10 20 nm

E 5 nm


10 20 30 40 50

100

120

140

160

180

200

(d)(c)

(b)

inte

nsity

/ a

. u

.

average particle separation / nm

(a)

(a) (b)

(c) (d)

50 nm

x

y


900 1000 1100 1200 1300 1400 1500

0

50

100

150

200

250

300

Inte

nsity,

a.

u.

Raman shift, cm-1

10

72

10 µm

Raman mapping

analyte:

4-mercapto-benzoic-acid (4-MBA)


600 700 800 900

0

5

10

15

900 950 1000 1050 1100

0

5

10

15

20

25

12.5

(b)

Inte

nsity (a

.u.)

(a)

12.5

16.64.2

Raman shift (cm-1)

22.0

Creatinine

100 µmol L-1

Urea

100 µmol L-1


±5 %

Int. Key Comparison (NMIs and Clinical Ref. Labs.)

F. Yaghobian (IGSM)

R. Stosch

S. Zakel

S. Wundrack

T. Weimann

B. Güttler

P. Mischnick


EMRP HLT05 Metalloproteins: Motivation

HLT05 Metalloproteine

Partner: LGC, LNE, BAM – DKfZ, Instand

• Nearly half the proteins need metals in active centre or as co-factor1

• Directives like the “Richtlinie der Bundesärztekammer” (directive of the German Medical Assembly) define method specific target value determined as the median for this method with method specific limits

• Reference measurement procedures and reference materials as required by JCTLM not available for many metalloproteins

• Reference materials (often lyophilised or spiked) show different behaviour compared to real clinical samples using analysis methods like immuno assays


Einsatzziel

Transferrin

transferrin

measurement method measurement procedure

comb. proteolyse – peptide analysis

HLT05 Metalloproteins

TOF-MS

HPLC-ICP-MS

SERS-Raman

HLT05 Metalloproteine

Partner: LGC, LNE, BAM – DKfZ, Instand


Overview







...in chemistry

(58)

Developing Metrological

Infrastructures

for Water Analysis in Europe

River Elbe between Hamburg and Cuxhaven © Vidicom / Christian Irrgang

(59)

Water - the European perspective

Water in the European Union

The water framework directive -

a common legislation for at

least 27 states and more than

500 million people

implementation of the

directive under drastically

different and changing

conditions in different

countries

(60)

Motivation

- 20 % of all surface waters in the European

Union are heavily polluted.

- 65 % of the drinking water originate from

ground water resources.

- 60 % of the European cities overuse their

ground water resources.

- 50 % of the EU wetlands (and their biota)

are endangered because of overused

ground water

- The artificially watered areas in the EU

increased by 20 % since 1985.

(e.g., European Environmental Agency, report 1995)

EU Water Framework Directive 2000/60/EC (WFD)

(61)

Chemical status: Where do we come from ?

Status GDR 1990 - main rivers and

many surface waters

are heavily contaminated

- only 42% of the

population has access

to an adequate

sewage system

- only 20% of water

courses can be used

for drinking water.

- life expectancy in certain areas is as much as ten years below the

state average

(EU press release P/90/67 Date: 27/09/1990)

"silver lake" near Bitterfeld & Wolfen, 1990

(62)

Aims

• to establish a legal framework to protect and restore clean water

across Europe and to ensure its long-term and sustainable use

• to expand the scope of water protection to all waters: surface

waters, transitional waters, coastal waters and groundwater

• to achieve a "good status" for all waters by a set deadline (2015)

• to achieve a water management based on river basins

• to implement a "combined approach" of emission limit values and

quality standards

EU Water Framework Directive 2000/60/EC

(63)

WFD Quality standards: Chemical status

Good chemical status (aims and strategies)

- ... groundwater should broadly be that it should not be

polluted at all (European Quality standards - EQS - level)

- compliance with all the quality standards for chemical

substances at European level.

- prioritisation mechanism for hazardous chemicals:

ensuring a minimum chemical quality, in relation to very

toxic substances, everywhere in the Community

(64)

Chemical status: priority substances

selection criteria

- aquatic ecotoxicity and human toxicity via aquatic exposure

routes

- Intrinsic hazard (toxic, persistent and liable to bio-

accumulate)

- evidence from monitoring of widespread environmental

contamination

- other proven factors indicating possible widespread

environmental contamination (e.g., industrial production

rates)

Decision 2455/2001/EC of the European Parliament and the Council

(65)

Selected 33 priority substances or groups of substances: (WFD) 2000/60/EC & QA/QC Directive (2009/90/EC)

- 4 heavy metals

- 14 pesticides

- 15 organic compounds of industrial origin

(e.g. flame retardants)

review every four years

Chemical status: priority substances

(66)

EUROMET Project 924

A sustainable traceability system providing Europe-wide comparable

measurement results in water monitoring under the WFD

organized by BAM, LNE, IRMM, PTB

Task:

Comparison measurements for selected priority substances:

heavy metals (Ni, Pb, Cd, Hg)

Aims:

- provide reference points (National Standards, CMCs) of sufficient

quality (suitable for EQS-requirements) to serve the WFD

- establish links to expert* and monitoring laboratories in Europe

*pt-providers, potential calibration laboratories (PCL)

- assess comparability and measurement uncertainties in the field

- validate methods of expert laboratories

- feasibility of a metrological dissemination system in Europe

Lake Pielinen, Finland


Requirements of the QA/QC directive (2009/90/EC)

to assure comparable measurement results

(… pursuant to Directive 2000/60/EC)

- Methods have to be validated and documented in accordance to

EN ISO /IEC17025

- Minimum performance criteria for the analytical method:

Limits of quantification ≤ 0.3 * EQS

Uncertainty ≤ 0.5 * EQS

- Monitoring laboratories have to participate in PT shemes

- organized by accredited or internationally recognized organisations

- evaluated according to ISO Guide 43-1 or ISO 13528 or equ.

priority substances: measurement requirements


Step 2: Validation of the measurement

procedure of the PCLs supported by NMIs

Step 3: Link of field laboratories and

PCLs in the framework of a PT scheme

NMIs

Monitoring Laboratories

Potential Calibration

Laboratories

Step 1: Link of NMIs and PCLs by

means of a comparison measurement

PCL: Potential Calibration Laboratories

EUROMET 924

EUROMET 924


Euramet 924 Step 3:

114 Test- and expert laboratories

4 NMIs (BAM, LNE, PTB, NCM)

Germany 33

Israel 2

Hungary 12

Bosnia-Herzegovina

1

Portugal 4

Slovenia 1

Czech 1

Croatia 4

Bulgaria 6

Austria 11

Italia 9

Romania 1

Norway 1

Sweden 4

France 18

Spain 5

Finland 1

Σ Countries:17 Labs: 114

EUROMET 924: step 3


NMIs:

PTB, BAM, LNE, IRMM

Calibration laboratories:

8 Germany

4 France

1 Sweden (NMI)

1 Norway

1 Finland

1 Romania (NMI)

1 Bulgaria (NMI)

1 Austria

2 Portugal

1 Italy

1 Hungary

2 Israel

1 Chile (NMI)

Metrology for European needs

Israel

(71) Braunschweig, 23.05.13 © PTB2010 (71) (71)

Target values for test laboratories

- Natural ground water (in mg/l, about Ca: 44, Na: 43,

K: 4, Mg: 8, heavy metals: maximal some 10 ng/l)

- Samples prepared and dispatched by PTB/IWW

Target uncertainty UTarget ≤ 0.5 * EQS

Limit of quantification βLOQ ≤ 0.3 * EQS

EQS βLOQ UTarget

in μg/l in μg/l in μg/l

Hg 0.050 0.017 0.025

Cd 0.090 0.030 0.045

Pb 7.2 2.4 3.6

Ni 20.0 6.7 10.0

(72)

Hg : CCQM K70 & EUROMET 924 step3

all participants: 66

βmean = 72.47 ng/l

RSD = 24.4 ng/l or 33.6 %

β RV = (72.4 ± 2.5) ng/l

test- and PCLs: 55

βmean = 72.9 ng/l

RSD = 26.6 ng/l or 36.5 %

β RV = (72.4 ± 2.5) ng/l

Metrology Inst. Expert Inst. Mon. Labs

(73)

EUROMET 924: subm. results - monitoring labs

concentration / µg/L

resu

lts r

etu

rned

/ %

(74)

• Organochlorine pesticides

• PBDE Polybromated Diphenylether

• PAH Polycyclic Aromatic Hydrocarbons

• TBT Tributyltin compounds

• SCCP 10 to C13 Chloroalkanes

CEN/TC230

Mandate 424 addressed to CEN:

Method development to support

WFD monitoring

critical pollutants:

priority substances for which suitable

measurement methods are not available

EMRP: WFDtraceability-project (2011 – 2014)

(EQS = 0,5 ng/kg for PBDEtotal)


Organic analysis • Organic analysis

• Element analysis

• Elektrochemistry

• Clinical Chemistry

• Gas Analysis

•

•

•

• pure materials

• gas mixtures

• certif. reference materials

gas mixtures for

environmental

protection

Food safety: residues in food

• clinical analytes

- hormones, enzymes

- new diagnostic

marker

• clinical analytes

- hormones, enzymes

- new diagnostic

marker

the German network: partners for chemical standards


Traceability for Chemistry in Germany

National Network in Germany

• Health (Clinical Cemistry: PTB, DGKL)

• Environment (air, water & soil: UBA, PTB, BAM)

• Food (Residues: BVL)

• Energy (natural gas: BAM)

• Forensics (breath alcohol testing, drugs of abuse (THC): PTB, BAM)

• Electrochemistry (pH, electrolyt. conductivity PTB)

• Inorganic Analyses (elements, element solutions: PTB, BAM))

• 15 accredited calibration laboratories

• legal authorities

• clinical reference laboratories of the BÄK

• air surveillance network of the Fed. States

• water surveillance network of the Fed. States

• Food surveillance network of the Fed. States

Dissemination (multiplicators)


• PTB acts as legally responsible national authority in an

international metrological network established by CIPM/CCQM

• It shares and delegates its work on the national level in a network

with dedicated institutes responsible for a defined subject field

• It establishes a linked & harmonized traceability structures with this

national network to support and ensure international comparability.

• If this is all established, the final goal of all the traceability efforts can

be achieved, namely:

Tested once, accepted everywhere Tested once, accepted everywhere

traceability structures in Germany: summary


thank you...

...for your interest !

...and to my colleagues in PTB, Dep. 3.1

in particular:

Andre Henrion

Detlef Schiel

Petra Spitzer

Rainer Stosch

Olaf Rienitz

Olaf Werhahn

metrology in chemistry - braunschweig...

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