1. New Developments in Atomic Spectroscopic Methods - with a Focus on Standardisation-
Dr Ulrich Borchers
PRIMER CONGRESO INTERNACIONAL DE DOCENCIA
E INVESTIGACIÓN EN QUÍMICA México, 27th - 29th October 2010

2. Dr Ulrich Borchers Food Chemist Head of Dept. Water Quality
Education
Exam in Food Chemistry (Technical University Braunschweig)
PhD Thesis: „Turnover of Nitrogen in Soil and Groundwater“ (Institute for Microbiology at TU Braunschweig)
Projects / memberships
Interlaboratory trials, Education of sampling personnel
Chairman CEN Technical committee „Water quality“
Member of the DIN main committee water analysis
Main activities
Chemical and microbiological analysis of water
Assessment of products for water treatment
Sampling techniques and strategies
Education of health authorities staff
Technical CEO IWW Nord

3. Topics Performance Requirements Atomic Absorption Spectrometry
Routine methods and recent developments
Revision of existing Hg methods (ISO/DIS 12846)
Atomic Fluorescence Spectrometry
Mercury
Hydride Forming Elements
ICP-OES
What’s new in ISO (2009)
ICP-MS
Is ISO still state-of-the-play?
Summary and Outlook

4. Heavy Metals to be Monitored (WFD)
DECISION 2455/2001/EC
List of Priority Substances (33)
Priority Substances
Present a significant risk to or via the aquatic environment
Priority Hazardous Substances
Subset of priority substances, which are toxic, persistent, liable to bioaccumulate or give rise to equivalent level of concern 4

5. Priority Substances/Other Pollutants
Trichloromethane
Octylphenol
Simazine
Priority Substances
Other Specific Pollutants
Alachlor
Atrazin
Benzene
Chlorpyrifos
Chlorfenvinphos
Di(2-ethylhexyl)phthalate (DEHP)
1,2-Dichloroethane
Diuron
Dichloromethane
Fluoranthene
Isoproturon
Lead and its compounds
Naphthalene
Priority Hazardous Substances
Pentabromodiphenylether
Anthracene
Cadmium and its compounds
C10-C13-Chloroalkanes
Hexachlorobenzene
Hexachlorobutadiene
Hexachlorocyclohexane
Endosulfan
Mercury and its compounds
Nonylphenol
Pentachlorobenzene
Polyaromatic Hydrocarbons (PAH)
Tributyltin compounds
Pentachlorophenol
Trichlorobenzenes
Nickel and its compounds
Trifluralin
DDT / p,p‘-DDT
Aldrin
Dieldrin
Endrin
Isodrin
Carbontetrachloride
Tetrachloroethylene
Trichloroethylene 5

6. Requirements: QA/QC Commission Directive
laying down, pursuant to Directive 2000/60/EC of the European Parliament and of the Council, technical specifications for chemical analysis and monitoring of water status
Provision of data of proper scientific quality
Basis for programme of measures
Comparability of monitoring results across Europe
Implementation of common principles and harmonised procedures for chemical monitoring 6

7. Commission Directive – Draft Proposal
Standardised methods and other validated method are to be used
Any method provided it is properly validated and meets certain performance criteria may be applied
Requirements on analytical methods
Validation according to EN ISO 17025
Limit of Quantification
 30 % of relevant EQS
Relative target Uncertainty
 50 %
If there is no EQS or if existing methods do not meet the criteria
„Best available technique“

8. LOQ Requirements for the 4 priority metals
LOQ [ng/l] (30 % of lowest EQS)
AAS
ICP-OES
ICP-MS
Cadmium 24
 (IWW = 30 ng/l)  
Mercury 15
 (AFS also OK)
Lead
2160
Nickel
6000

9. Topics Performance Requirements for WFD monitoring
Atomic Absorption Spectrometry
Routine methods and recent developments
Revision of existing Hg methods (ISO TC 147/SC2/WG61)
Atomic Fluorescence Spectrometry
Mercury
Hydride Forming Elements (ISO TC 147/SC2/WG53)
ICP-OES
What’s new in BS EN ISO (2009)
ICP-MS
short outlook to relevant methods for DW
Summary and Outlook

10. AAS in Water Analysis (1)
The Initiation!
May 1952: First idea on F-AAS by Sir Alan Walsh (born 1916 in England, BSc/MSc in Manchester)
1961: first publication on the „graphite tube“ by Boris L´vov
1962: first commercial F-AAS system

11. Standardisation of Methods: Co-operation BSI with CEN and ISO
BSI Committee EH/3 „Water analysis“
British “mirror committee” of the respective
European and
International committee
CEN TC 230 „Water Analysis“
ISO TC 147 „Water Quality “

12. Existing Set of Methods
Nearly complete set of BS or BS EN (ISO) methods for relevant metals in water
Lots of single element standards
But also horizontal standards
e.g. BS EN ISO (22 elements by GF-AAS)
Complete list see:
Recent revisions:
Flow systems for HG (instead of batch systems)
More general description of light sources
More performance based approaches
Alternatives for digestion techniques
Separate standards for digestion (BS EN ISO /-2)

13. Overview: Digestion Techniques for Water
batch systems
Continuous systems
Open systems
Reflux systems
UV systems
Ultrasonic systems
Closed systems
Convective heat transfer
Microwave assisted
Convective heat transfer
Microwave assisted

14. High-Resolution Continuum Source AAS
..... The most interesting development in AAS in the last few years.
The advantages
Just one light source for all elements
Xenon short-arc lamp
(W-X-lamp alternatively)
All AAS elements are pre-configured
Sequential multi-element analysis (like ICP-OES) as standard
charge-coupled device (CCD)
Simultaneous background correction
Easy to operate and robust
Improved analytical performance
More analytical possibilities

15. AAS with continuum source (scheme)
Optical pathway: LS AAS
Optical pathway: CS AAS

16. High Resolution AAS with Continuum Source - resolution LS AAS versus CS AAS
Line Source AAS
emission Intensity of the Mn line source
Manganese–Triplet:
279,4817 nm
279,8269 nm
280,1085 nm
Continuum source AAS
absorption spektrum

17. Topics Performance Requirements for WFD monitoring
Atomic Absorption Spectrometry
Routine methods and recent developments
Revision of existing Hg methods (ISO TC 147/SC2/WG61)
Atomic Fluorescence Spectrometry
Mercury
Hydride Forming Elements (ISO TC 147/SC2/WG53)
ICP-OES
What’s new in BS EN ISO (2009)
ICP-MS
short outlook to relevant methods for DW
Summary and Outlook

18. Existing Hg AAS Standards in the Field of Water
A) methods without Enrichment:
ISO 5666 standard, Water Quality – Determination of Mercury
BS EN 1483 standard, Water quality - Determination of mercury - Method using atomic absorption spectrometry

19. Existing Hg AAS Standards in the Field of Water
B) Methods with Enrichment:
ISO standard, Water Quality – Determination of Mercury after Enrichment by Amagalmation
BS EN standard, Water Quality – Determination of Mercury after Enrichment by Amagalmation

20. Aim of the Discussion on the Revision of Hg Standards
Main items of discussion were:
To consider state-of-the-art technology
e.g. High resolution CS AAS
e.g. modern systems for digestion
Is the time high for standards on speciation analysis of Hg?
Result:
Discussion on robust methods is still open
No surveillance limits for Hg species exist
For investigative monitoring and specific questions helpful
Standardisation should not start at the time being

21. Strategy for the New BS EN ISO Standard!
Only 1 standard for Hg by AAS is needed
with 2 alternatives (2 parts)
Part 1: Hg without enrichment
Part 2: Hg with enrichment (amalgamation)
Only one reduction reagent (Sn(II)Cl)
as described in BS EN ISO (Harmonisation of approaches!)
No alternative digestion steps
NaBH4 in the informative Annex
if it can be shown that it works in combination with the new digestion

22. Strategy for the New BS EN ISO Standard!
Working range:
0,005 µg/L with enrichment / 0,1 µg/L without
Stabilization of samples / Pre-digestion:
Potassium bromate - Potassium bromide digestion
Note: reduction of bromate (detoxification!)
Reagent should be added in the lab (health/safety hazards)
Elimination of excessive oxidising reagent
L-ascorbic acid solution, ρ(C6H8O6) = 100 g/l
Reduction of Hg
Tin(II)chloride solution, ρ(SnCl2 ⋅ 2H2O) = 20 g/l
Atomizer
Cold vapour generation system
Quartz or glass tube atomizer
Background correction recommended

23. Strategy for the New BS EN ISO Standard!
Automated stand-alone mercury flow systems
flow injection systems or continuous flow systems should be allowed
Radiation source, e.g.
hollow cathode lamps
electrodeless discharge lamps.
continuum radiation source (e.g. a Xenon short arc lamp)
Formation of the CV
continuous flow vapour generator
Enrichment by amalgamation of Hg
Quarz tube with suitable heating and absorbent (e.g Gold-Platinum Gauge)
other absorbents are allowed if the user demonstrates the fitness-for-purpose
desorption of Hg at 600° C (minimum)

24. Stragegy for the new EN/ISO standard!
Types of calibration
standard calibration
standard addition method
Validation data
A new Interlab trial has to be performed
Samples with low Hg conc. are needed to prove the application range
e.g. drinking water with Hg = 20 ng/l
Informative Annexes
no alternatives with respect to the Bromine Chloride combined preservation and digestion step
NaBH4 has to be checked whether it works with the potassium bromate/bromide reagent

25. State of the Work and Further Steps
ISO Committee Draft (CD) 12846
Water quality — Determination of mercury - Method using atomic absorption spectrometry (AAS) with and without enrichment
Deadline for CD comments:
Preparation of the Draft International Standard (DIS) version for enquiry until end of July 2009
Interlaboratory trial for the validation of the method
End of 2009

26. Topics Performance Requirements for WFD monitoring
Atomic Absorption Spectrometry
Routine methods and recent developments
Revision of existing Hg methods (ISO TC 147/SC2/WG61)
Atomic Fluorescence Spectrometry
Mercury
Hydride Forming Elements (ISO TC 147/SC2/WG53)
ICP-OES
What’s new in BS EN ISO (2009)
ICP-MS
short outlook to relevant methods for DW
Summary and Outlook

27. Existing Hg AAS Standards in the Field of Water
C) Methods using AFS instead of AAS:
EN standard, Water quality — Determination of mercury — Method using atomic fluorescence spectrometry
BS EN ISO standard, Water quality — Determination of mercury — Method using atomic fluorescence spectrometry
EPA 1631: Method 1631, Revision E: Mercury in Water by Oxidation, Purge and Trap, and Cold Vapor Atomic Fluorescence Spectrometry
EN is now withdrawn as ISO has been published

28. Relevant Items to Mention
AFS is the most sensitive technique for Hg!
In Germany excellent perfomance data in water PTs
Differences between BS EN and BS EN ISO 17852
EN 13506: Potassium Dichromate as preservation reagent
ISO 17852: Potassium bromate – Potassium bromide
Most relevant problems in practical application
Blanks (lab and reagents!!)

29. Statistical Data for Hg by AFS (CEN/ISO Interlaboratory Trial)

30. Hydride Forming Elements by AFS
ISO/CD “Determination of antimony – Part 1: Method using hydride generation atomic fluorescence spectrometry (HG-AFS)
ISO/DIS “Determination of arsenic – Part 1: Method using hydride generation atomic fluorescence spectrometry (HG-AFS)
ISO/DIS “Determination of selenium – Part 1: Method using hydride generation atomic fluorescence spectrometry (HG-AFS)

31. Hydride Forming Elements by AFS
ISO/CD “Determination of antimony – Part 1: Method using hydride generation atomic fluorescence spectrometry (HG-AFS)
ISO/DIS “Determination of arsenic – Part 1: Method using hydride generation atomic fluorescence spectrometry (HG-AFS)
ISO/DIS “Determination of selenium – Part 1: Method using hydride generation atomic fluorescence spectrometry (HG-AFS)
All 3 projects are cancelled due to massive exceedance of target dates (dormant stage)

32. Topics Performance Requirements for WFD monitoring
Atomic Absorption Spectrometry
Routine methods and recent developments
Revision of existing Hg methods (ISO TC 147/SC2/WG61)
Atomic Fluorescence Spectrometry
Mercury
Hydride Forming Elements (ISO TC 147/SC2/WG53)
ICP-OES
What’s new in BS EN ISO (2009)
ICP-MS
short outlook to relevant methods for DW
Summary and Outlook

33. Topics Performance Requirements for WFD monitoring
Atomic Absorption Spectrometry
Routine methods and recent developments
Revision of existing Hg methods (ISO TC 147/SC2/WG61)
Atomic Fluorescence Spectrometry
Mercury
Hydride Forming Elements (ISO TC 147/SC2/WG53)
ICP-OES
What’s new in BS EN ISO (2009)
ICP-MS
short outlook to relevant methods for DW
Summary and Outlook

34. What’s New in BS EN ISO 11885 (2009)
Main changes (compared to the 1998 ed.):
New Performance Data from an validation trial in with 28 labs from 6 countries (UK = 1)
Clause 6: Interferences: fully re-structrured; more detailed description
Amendments to consider the “State-of-the-play”

35. Performance Data (Interlab trial 2006)
Par l
nAP X
xass 
CVR
CVr (2006)
CVr (1996) %
µg/l Al 24
4,1
120
125,3
95,7
9,8
2,9
4,3 As 18
0,0
63,3
62,5
101,2
8,6
5,8 - B 20
9,1
64,1
63,6
100,9
8,1
3,5 Ba 23
4,2
330
3,9
2,1
3.8 Ca 26
66900
66310
5,7
2,2
6,0 Cd
13,5
14,0
96,3
5,5
1,8
2,8 Co 22
19,4
20,0
96,8
4,5
2,5 Cr
16,2
16,0
9,0
3,1
3,3 Cu 25
634
662,7
3,7
1,2
5,1 Fe
4,0
196
208,5
93,9
4,7
1,7
5,0 K 21
5490
5443
2,3
10,6

36. Performance Data (Interlab trial 2006)
Par l
nAP X
xass 
CVR
CVr (2006)
CVr (1996) %
µg/l Li 16
5,9
131
134
97,8
10,9
2,5 - Mg 26
3,8
10160
10223
99,4
2,6
1,2
6,0 Mn 27
0,0
51,0
53,0
96,3
4,9
1,8
2,7 Na 24
49500
47720
103,8
4,8
1,6
9,7 Ni 23
25,9
26,9
96,4
7,4
3,3 P 21
4,5
884
901,6
98,0
6,8
1,3
1,7 Pb 20
18,4
20,0
92,1
15,8
8,2 S
11,3
19180
4,7
2,1
5,1 Si 17
10,7
3280
3269
100,2
2,3 Sr
495
4,4 Zn
4,2
124
127,5
97,3
1,9
5,4

37. Other Instrumental Developments (catchwords)
Hydride Generation ICP-OES
For Arsenic species
Microwave Plasma torches (MPT)
Ar or He plasma, about 100 Watt
New types of nebulizers, e.g.
Dual nebulizers
Micro-nebulizers
A very recommendable review:
N.H. Bings; A, Bogaerts, J.A.C. Broekart; Atomic spectrometry; Anal. Chem (2008) 80, pp

38. Topics Performance Requirements for WFD monitoring
Atomic Absorption Spectrometry
Routine methods and recent developments
Revision of existing Hg methods (ISO TC 147/SC2/WG61)
Atomic Fluorescence Spectrometry
Mercury
Hydride Forming Elements (ISO TC 147/SC2/WG53)
ICP-OES
What’s new in BS EN ISO (2009)
ICP-MS
short outlook to relevant methods for DW
Summary and Outlook

39. Uranium in Drinking Water
DHI (DK) study for COM DG ENV: New Limit for Drinking Water in Europe
10 to 30 µg/l
ICP-MS (Uranium-Isotope 238)
BS EN ISO
LOQ/application range: 0,1 µg/l (to 0,01 µg/l)
External calibration
Internal Standard
Performance data IWW
LOQ: 0,02 µg/l
Precision: 0,3 %
Exp. U: 6 % (at level 2 µg/l)
Potentiostatische Anreicherung im komplexierten Zustand auf der Oberfläche einer stationären Quecksilbertropfelektrode und anschließender voltametrischer Bestimmung
Komplexbildner: Chloranilsäure

40. Uranium in German Drinking Waters
Name of the Study
Max. Value [µg/l]
Ratio 2 – 10 µg/l [%]
Ratio >10 µg/l [%]
Number of results
KUS-Study Germany
26,2
7,5
0,5
1790
LfU
Bavaria 40
19,7
9,4
704
IWW Northrine-Westfalia 13
8,5
0,2
457
Foodwatch Germany 39
9,3
1,8
8177

41. IC – ICP-MS coupling: Bromate analysis
Limit for Drinking Water in Europe
10 µg/l IC
Perkin Elmer HPLC Series 200
Column
IonPac AS 16 (4 x 250 mm)
NaOH (30 mM), 0,9 ml/min
ICP-MS
PerkinElmer, Elan DRCII,
Performance data IWW
LOQ: 0,02 µg/l
Precision: 0,3 %
Exp. U: 6 % (at level 2 µg/l)

42. Topics Performance Requirements for WFD monitoring
Atomic Absorption Spectrometry
Routine methods and recent developments
Revision of existing Hg methods (ISO TC 147/SC2/WG61)
Atomic Fluorescence Spectrometry
Mercury
Hydride Forming Elements (ISO TC 147/SC2/WG53)
ICP-OES
What’s new in BS EN ISO (2009)
ICP-MS
short outlook to relevant methods for DW
Summary and Outlook

43. Summary (1)
AAS, ICP-OES, ICP-MS and AFS offer an optimal instrumentation
Available instruments are in general fit for purpose (also for WFD monitoring)
In routine water labs a combination of two techniques is necessary (e.g. HG-AAS/AFS and ICP-MS or ICP-OES)
None of these classical techniques is going to be superseded
High automation level guarantees marketable routine analysis

44. Summary (2)
Atomic spectrometry takes the centre stage in inorganic water analysis
Modern methods meet high demands on
specificity, selectivity, sensitivity
Enjoyable amount of innovation from research and practice
Routine and surveillance analysis rely on standardised methods