GROWTH – DEDICATED CALL – 1/00
TOPIC III.5
Construction Products in contact with Drinking Water
1. CONFORMITY WITH THE WORK PROGRAMME
This topic falls under the Competitive and Sustainable Growth Programme, generic
activity Measurement and Testing. Specifically, it is related to Objective GROW-20006.2.1 Methodologies to support standardisation and Community policies for which
expressions of interest have been called.
It develops, improves and validates testing methods which will support the elaboration
of harmonized European product standards necessary for the producers and the national
regulators of the Member States for the implementation of the Directive 89/106/EEC on
construction products.
2. KEYWORDS
Construction Product Directive, harmonisation of test methods, harmonised product
standards, elimination of trade barriers in the construction products sector, promotion of
trade, European Approval Scheme.
3. SUMMARY OF OBJECTIVES AND JUSTIFICATION
This topic has the objective to harmonise the existing National test methods for
Construction Products in contact with Drinking Water (CPDW) in the framework of the
development of a European Approval Scheme (EAS). The EAS is set up in the
framework of the implementation of both the Construction Product Directive
89/106/EEC and the Drinking Water Directive 98/83/EC. These directives define
Requirements for the water supply works, stating that the CPDW may not cause
“pollution or poisoning of the water”. The objective is to create a single market for
CPDW by the harmonisation of the tests needed for approval of the relevant products.
The EAS will be based on European Norms (ENs), developed at CEN, and on an EC
Decision defining the acceptance criteria.
The work that is required aims to develop, to improve and to validate 4 test methods on:
 cytotoxicity and genotoxicity
 the potential of the CPDW to promote microbial growth
 the screening for unsuspected compounds by GC-MS (Gas Chromatography - Mass
Spectrometry)
 the influence of high levels of disinfection treatment on the inertness of CPDW
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In principle, these tests should apply to all materials (organic, metallic, cementitious).
However, if one (or several) test(s) could not be used for one (or several) material(s), a
full justification would have to be provided.
4. BACKGROUND
Member States operate National Approval Schemes (NAS) for the CPDW. These NAS
are all intended to protect the health of consumers. However, since the NAS are issued
from different philosophy/traditions and since they follow different routes, a system of
mutual recognition cannot be implemented. This constitutes obvious trade barriers for
the CPDW (pipes, tanks and ancillaries such as taps, valves, etc.), since these products
shall be certified/approved in each Member State.
At the 46th session of the Standing Committee on Construction, held on April 8-9 1999,
the Member States agreed unanimously on a draft European Approval Scheme (EAS)
and on the related programme of co-normative research that would allow the validation
of the scheme. In April 1999, the Commission requested the Member States to nominate
officially a Representative to attend the meetings of the Regulators Group for CPDW
(RG-CPDW). This Working Group already met twice in June and October 1999. The
Industry main associations (eg APME, Cembureau, CEPMC, EuPC, Eureau, Euroduct,
Eurometaux) and the main technical committees (TCs) of the Comité Européen de
Normalisation (CEN) were/are invited as observers in the RG-CPDW meetings.
A feasibility study on the possible convergence of 4 National Approval Schemes led to
a positive answer and allowed the definition of a draft EAS.
5. ECONOMIC AND SOCIAL BENEFITS
The EAS will provide significant economic benefits to industry permitting economies of
scale and giving the possibility to the manufacturers of CPDW to commercialise their
products in all the Member States, and probably other European Countries, since a
unique approval scheme will be agreed by all the Regulators.
The implementation of an EAS will also lead to a reduction of the overall
certification/approval cost. The approval of a typical CPDW in one Country currently
costs about EURO 20,000. Based on UK data, it is estimated that a typical producer
offers four products for sale in six different Member States. This means a cost of about
EURO 480,000 in approval certificates. The development of an EAS offers the potential
to reduce the costs for such a typical producer to less than EURO 100,000. The EAS
will therefore promote trade between Member States and provide particular benefits to
the small and medium size enterprises, which did/do not have the resources to obtain
multiple approvals for their products.
Since the EAS will be based on harmonised standards, water test laboratories may also
profit through competition and selection as accredited CPDW-test laboratory, e.g. based
on their results in inter-laboratory comparison exercises.
The European society will also take benefit from the development of an EAS, since the
related consumer protection level will not any more be fixed at 15 different National
levels, but at a unique agreed upon level, that will not compromise any of the existing
levels.
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As a further consequence, the implementation of an EAS might also lead to a reduction
in the cost of the materials used in public works (via public procurement) and in private
works, through an increased competition of the relevant product manufacturers in
Europe.
6. SCIENTIFIC AND TECHNOLOGICAL OBJECTIVES
A- Cytotoxicity and genotoxicity
Until now, only two Member States (F and UK) use the cytotoxicity test in the
assessment of CPDW. The French test (AFNOR XP P 41-250-3) is based upon an
assessment of the inhibition of RNA synthesis caused by compounds present in the
leachates. The UK British Standard BS 6920 is based upon the growth of monkey
kidney cells in the leachates.
The competent regulatory authorities of the Member States have agreed that:
 a cytotoxicity test is necessary to assess the risk of CPDW for consumers
 this test is complementary to the GC-MS screening test for unsuspected compounds
 the existing French cytotoxicity test is considered the most appropriate. However,
there is a need to find an alternative method to avoid the present use of tritiumlabelled media.
 a genotoxicity test should go alongside the cytotoxicity test and the choice of an
appropriate test needs further investigations
The scientific and technical objectives of the research on cytotoxicity and genotoxicity
are:
 to develop a harmonised test (based on he French cytotoxicity test) which will be
used by the approved laboratories that will be in charge of the assessment of CPDW
 to elaborate a genotoxicity test that will be complementary to the cytotoxicity test
 to carry out an inter-laboratory comparison exercise among European CPDW-test
laboratories
B- The potential of CPDW to promote microbial growth
A harmonised method to test CPDW for the potential to support microbiological growth
is necessary to ensure that these materials do not promote the growth of
microorganisms. Growth of microorganisms can lead to consumer complaints of taste
and odour. More importantly, the growth of pathogenic organisms such as Legionella
can cause a risk to the consumer’s health.
Three national test procedures are applied at present. The UK British Standard BS 6920
measures dissolved oxygen depletion as a surrogate for microbial growth. The German
DVGW W270 method measures the volume of the biofilm that is formed on the surface
of the materials. The Dutch BFP method measures adenosine-triphosphate (ATP) as an
indication of the concentration of active biomass.
The competent regulatory authorities of the Member States have agreed that:
 it was not practicable to produce a European test based on harmonisation of the
three existing test procedures
DC 1/00/Topic III.5/ Pg 4

there was unawareness of any other test procedure that might be suitable for
consideration
 the ATP-based test probably provides the best basis for assessing the potential to
support microbiological growth
The scientific and technical objectives of the research on the promotion of microbial
growth by CPDW are:
 to improve the existing ATP-based test method
 to optimise the test conditions in order to obtain an acceptable level of information
in a time-scale as short as possible and thus minimise the cost of testing
 to carry out an inter-laboratory comparison exercise among European CPDW-test
laboratories
It is also an important point that micro-organisms populations vary across Europe.
Therefore the differences among different micro-organisms seeds and temperatures for
their growing should be considered by project proposals.
C- The influence of high levels of disinfection on the inertness of CPDW
Products used in public water distribution systems are often treated after installation or
renovation with high levels of disinfectants, to prevent the risk of microbiological
contamination. In case of severe bacterial contamination (Coliforms, Legionella, etc.),
the plumbing systems are also submitted to stringent disinfection procedures. In both
cases, the disinfectant is typically chlorine, but can also be peroxides.
Some countries have a good knowledge on the inertness of the CPDW when submitted
to high levels of disinfectants. Other countries ignore the behaviour of their products in
such conditions. How to build the assessment of the possible effects of disinfection on
CPDW into harmonised standards is a major problem. Although such procedures are
already included in some standards produced by CEN TC-164, information is needed to
determine the acceptance criteria in the next European Approval Scheme.
These disinfection treatments can affect the quality of materials and in consequence
increase the migration of substances from the products and have undesirable effects on
health and hygiene of the consumers. To avoid the risk of leaching of disinfection byproducts such as haloforms, bromates, and substances directly linked with some of the
organic materials (epichlorohydrin, acrylates, etc.) it is essential to include a simulation
of disinfection treatment in the European Approval Scheme for organic CPDW.
The scientific and technical focus of the work on effects of disinfection on the inertness
of organic CPDW is:
 to develop a test method complementary to existing standards developed by CEN
TC-164 in the field of inertness of CPDW
 to assess existing organic CPDW used in Europe
 to carry out an inter-laboratory comparison exercise among European CPDW-test
laboratories
DC 1/00/Topic III.5/ Pg 5
D- Screening for unsuspected compounds by GC-MS
The aim of the GC-MS identification procedure is to include as wide a range of organic
substances as possible, since the nature of potential contaminants, that may be present in
the leachates, is not known. There may be several reasons why unsuspected compounds
would be present.
At present only UK and France routinely apply such GC-MS assessments. The
competent regulatory authorities of the Member States have agreed that:
 these two national test methods should be used to form the basis of a harmonised
GC-MS method capable to detect and identify compounds at relatively low levels
(µg l–1)
 the calibration of the test instruments shall be chosen accordingly.
 to carry out an inter-laboratory comparison exercise among European CPDW-test
laboratories
 The research must investigate the setting up a centralised database for all substances
identified, that would include the GC-MS data on the substances that are detected
when the assessment is applied in routine use as part of the EAS. The availability of
such a database will permit easier identification of the substances involved and
would contribute to make future GC-MS assessments of materials more cost
effective.
The following aspects for the harmonisation of the GC-MS assessment will need to be
studied to decide the how rigidly they will need to be specified to ensure reasonably
comparable data. To carry out the studies a selection of organic compounds to be
studied that reflect those that may leach from materials and cover a reasonable range of
chemical properties will need to be made. Provided the harmonised method is shown to
be adequate for these compounds, it is advisable to study a range of materials to
demonstrate that there are no significant matrix effects with leachates.
Migration procedure – Laboratories must use a harmonised procedure for undertaking
leaching tests on materials
Extraction technique – The following will need to be harmonised: sample volume
extracted, pH of the sample, the solvent used and the volume used for the extraction, the
number of extractions, and the final volume to which the solvent extract is concentrated.
GC-MS operating parameters
GC: The following will need to be standardised: column type, volume of the
concentrated extract analysed, conditions of the GC run etc. The main study will be
aimed at deciding how rigidly the GC columns and operating conditions need to be
controlled.
MS: The following will need to be harmonised: mass range, scan speed, minimum mass
spectrometric resolution, and ionisation mode. A range of types of mass spectrometers
(e.g. magnetic sector, quadrupole and ion-trap) are needed in the evaluation to assess
any effects associated with the use of different instrumentation. The sensibility and the
effective range of each instrument will be evaluated, and the necessary calibration
undertaken. This range should reflect the range likely to be used when the harmonised
GCMS procedure is applied in practice evaluation so that any effects associated with the
use of different instrumentation can be evaluated. The aim is not to propose specific
DC 1/00/Topic III.5/ Pg 6
instrumentation but to ensure that the performance of existing equipment falls within an
acceptable range.
Treatment of the MS data – background subtraction, subtraction of data for substances
in the leachates which do not originate from the test material, etc.
The basis of the identifications and reporting of data – The identification of unknowns
from the mass spectra (and supporting GC information) is a complex matter and
different laboratories use different approaches. Standardisation of the approach to the
identification process needs to be agreed. The way, in which the data should be
reported, needs to be harmonised. For example, apart from data, such as copies of the
TIC or RIC chromatograms, mass spectra and peak areas, laboratories may be required
to provide tables of 'final' results. These should include the following:
 all peaks assumed to originate from the material
 estimated concentration of all peaks detected (see below)
 depending on the degree of identification, their full chemical name, type of the
chemical or main ions detected
 GC retention time.
The basis of the quantification – the primary aim of the GCMS general survey
approach is to identify unknown substances. However, it is possible at the same time to
provide a rough estimate of the concentrations of the compounds detected and the
procedure for achieving this needs to be harmonised. The identified unknown may have
a published allowable threshold concentration in drinking water or such a concentration
may need to be calculated from appropriate toxicity data. It is important to note that
once the unknown has been identified and a pure sample obtained for calibration
purposes, a more specific alternative analytical technique usually needs to be applied to
obtain accurate quantitative results for comparison with thresholds. However, this is not
a part of the intended research.
E- General co-ordination
It is expected that this research topic will contribute to set up the scientific bases of a
consistent 4 tests system. The overall consistency and complementarity (no
overlapping) between the 4 tests (absence of gaps and/or duplicate measures,
complementarity, etc.) are therefore parts of the objectives. The repeatability and the
cost effectiveness of the 4 tests batch have to be carefully evaluated, and comparisons
made with existing similar testing.
This testing process concerns, in principle, all materials and all products (including
small ancillaries). If any material and/or product had to be excluded from any one of the
4 tests, then the full justifications of this exclusion should be reported.
As there are European specialised experts that would not participate in this research
programme, a workshop/conference shall be organised at the end of the research
period, intending a detailed presentation of the results. Member States should be
allowed to send one expert per speciality. CEN-TCs concerned should also be invited to
send Representatives.
The three main industrial sectors concerned (metal, concrete, polymers) should be
involved in the programme from the beginning.
DC 1/00/Topic III.5/ Pg 7
7. TIME SCALE
The results are expected to be available by the end of 2002. It is anticipated that most of
the results will be delivered to the specifications writers, at CEN, so that new European
Norms (ENs) be prepared and published. Other topics, such as reasonable acceptance
criteria, will constitute the scientific bases of an EC Decision. Both the EC Decision and
the ENs published by CEN will be part of the EAS. The Commission – Enterprise and
Environment DGs –expects the EAS to become operational the latest by 2005.
8. IMPORTANT ADDITIONAL INFORMATION
8.1
National standards
Cytotoxicity
AFNOR XP P 41-250-3 (F), BS 6920 (UK)
Microbial Growth
BS 6920 (UK), DVGW W270 (D), BPP (NL)
GC-MS
BS 6920 Part 4 (UK)
8.2
Relevant European publications
General
Ashworth, J & Colbourne, JS (1987a). The testing of non-metallic materials for use in
contact with potable water, and the interrelationships with in-service use. In Industrial
Microbiological Testing (A Hill & J Hopton, eds). Society for Applied Bacteriology
Technical Series No. 23, 151 to 170.
Ashworth, J (1998). Approval testing for drinking water construction products. In
Drinking Water Research 2000, Published by the Drinking Water Inspectorate.
M.J. Benoliel, Influência de Produtos Químicos e de Materiais na Qualidade da Água de
Consumo Humano- Ensaios realizados pela EPAL, 4º Congresso da Água, APRH,
Lisboa, 23-27 Março 1998
M.J. Benoliel, Materiais em Contacto com a Água - 20º Congresso Brasileiro de
Engenharia Sanitária e Ambiental, ABES, Rio de Janeiro-Brasil, Maio de 1999
Boyd HB., Hvor farligt er drikkevands indhold af miljøfremmede stoffer? (Just how
dangerous are environmental chemicals in drinking water?). Vandteknik 1998; 2, 6264.
Colbourne, JS (1985). Materials usage and their effects on the microbiological quality
of water supplies. Journal of Applied Bacteriology Symposium Supplement, 1985,
47S to 59S.
Hambsch, B., Wagner, I.: Water quality in distribution, National Report Germany,
Blackwell Science Ltd., IWSA World Congress 1997
DC 1/00/Topic III.5/ Pg 8
Kooij, D. van der, Suylen, G.M.H., en Genderen, J. van. 'Interaction of water with pipes',
Water Supply 9, 1991, 3/4, P. SS12-1.
D. Loidl, A. Pagani, Ch. Hametner, M. Tacker: Kunststoffe im Lebensmittel- und
Trinkwasserbereich, Österr. Kunststoff-Zeitschrift 29, 308-310, 11/12 (1998)
Morlot M. (1993), Materials in contact with the public water distribution system standards and legislations, Journées Eau et Santé, Nancy, November
Premazzi G., Cardoso C., Conio O., Palumbo F., Ziglio G., Borgioli A., Griffini O.,
Meucci L., Exposure of the European population to trihalomethanes (THMs) in
drinking water, EUR 17335, Office for Official Publications of the European
Communities, Luxembourg (1997)
Van den Hoven, Th.J.J., D. van der Kooij, Vreeburg, J.H.G. en Brink, H. (1994). Methods
to analyse and to cure water quality problems in distribution systems'. Proceedings
IWSA-congres Zürich .
Van der Jagt, H. (1998). “Approval testing of products for effects of materials in water
quality in the Netherlands”. Proceedings paper, CIB W62, symposium at Rotterdam.
Instituut voor studie en Stimulering van Onderzoek op het Gebied van
Gebouwinstallaties. September, 21-23, 1998
Van der Kooij, D., Th. J.J. Van den Hoven, Schulting, F.L. and J.T. van der Zwan.1988.
'Influences of materials on water quality degradation in distribution systems'. Special
Subject 21, Proceedings IWSA Conference (1988), p.SS 21-1-21-9.
Van der Kooij, D..1995. Significance and assessment of the biological stability of drinking
water. In Water Pollution: Quality and treatment of drinking water (vol. ed. J. Hrubec),
The handbook of Environmental Chemistry, Vol. 5 Part B (ed. O. Hutzinger.) pp. 89102.
Van der Kooij, D., J.H.M. van Lieverloo, J.A. Schellart and P. Hiemstra. 1999.
Maintaining quality without a disinfectant residual. J. AWWA 91(1):55-64.
Van der Kooij, D., J.H.M. van Lieverloo, J. Schellart and P. Hiemstra. 1999. Distributing
drinking water without disinfectant: highest achievement or heigth of folly? J. Water
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Wessels SW, Boyd HH. Novel Foods: Hvordan vurderes sikkerheden? (How is safety
assessed?), Alimenta 1998; 21, 2, 7-9.
Cytotoxicity & genotoxicity
Danish Toxicology Centre and Water Quality Institute: Humantoksikologiske
vurderinger i forbindelse med depotindsatsen (Human toxicological evaluations in
connection with deposit effort). In Danish. Report No. 16, 1996 National
Environmental Protection Agency
Grummt T: Genotoxikologische Untersuchung von Tracersubstanzen. Abschlußbericht
an das Geologische Landesamt Baden-Württemberg 1996. (Genotoxic studies of tracer
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Annual Meeting of the EEMS. Pharmacol Toxicol 85 (1999) Suppl. 1, p. 33.
Lenz, S., Sacher, F., Brauch H.-J., Hambsch, B.: Entwicklung chemischanalytischerVerfahren zur Erfassung gentoxischer Substanzen in Wässern. Vom
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Liimatainen A, Grummt T: In vitro genotoxicity of chlorinated drinking water processed
from humus-rich surface water. Bull Environ Contam Toxicol 41 (1988) 143-156.
Noij, Th.H.M., Brandt, A and Van der Kooi, M.M.E., 'On-line monitoring of polar organic
compounds by the integration of sample pre-concentration and chromatographic
analysis', Water Supply 14, nos 3/4 (1996), p.505-508
DC 1/00/Topic III.5/ Pg 9
Noij, Th.H.M. and Van der Kooi, M.M.E., 'Automated analysis of polar pesticides in water
by on-line solid-phase extraction and gas chromatography using the co-solvent effect',
Journ. High Resol. Chromatogr. 18 (1995) p.535-539
Microbiological growth
Albrechtsen, H.-J., P. Nielsen, P.M. Smith, & T.H. Christensen. 1996: Significance of
biomass support particles in laboratory studies on microbial degradation of organic
chemicals in aquifers. Water Research, 30, (12): 2977-2984.
Ashworth, J & Colbourne, JS (1987b). Microbial alterations of drinking water by
building services materials - field observations and the United Kingdom Water
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Boe-Hanssen, R., H.-J. Albrechtsen, E. Arvin & C. Jørgensen. 1999: Development of a
model distribution system for studies of changes in water quality and microbial
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Contribution on the Bacterial Regrowth Potential (BRP) and the By-Products
Formation in Drinking Water Treatment. Proceedings Water Quality Technology
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Hambsch, B., Werner, P.: Control of Bacterial Regrowth in Drinking-Water Treatment
Plants and Distribution System. Water Supply, Vol. 11, Nos 3/4 (1993), p. 299-308.
Noij, Th.H.M. and Schulting, F.L., 'Trends in analytical techniques for the analysis and
identification of organic micropollutants in water', Water Supply 11 (1993) p.59-77
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micropollutants in water by GC/MS, Journal français d’Hydrologie, 22(2)pp.
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J.A. Schellart. (1995). Multiple barriers against micro-organisms in water treatment and
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Withers, N., Drikas, M., Hambsch, B.: Bacterial Regrowth Potential in German and
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Actions of disinfectants
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DC 1/00/Topic III.5/ Pg 10
Schmidt, W., Hambsch, B., Petzoldt, H.: Formation of bioavailable disinfection byproducts. Proceedings IWSA-Specialized Conference on Drinking Water Distribution
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Gas Chromography, Mass Spectrometry
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aqueous organic compounds. An innovative technique for solute sampling
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Materials Testing Leachates. WRc Report DWI 3874.
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