3rd International Fresenius Conference on Environmental Risk Assessment of Biocides 7 May 2014, Mainz (GER)

1. Monitoring biocides in the
rivers Rhine and Meuse
important sources for drinking water
production
André Bannink, RIWA
7 May 2014
environmental risk assessment of biocides
3rd International Fresenius Conference, Mainz (D)
1

2. Outline
• RIWA: who are we?
– Why do we monitor water quality?
• Which biocides concern(ed) us? Three
examples
1. 3-(3,4-dichlorophenyl)-1,1-dimethylurea
2. N,N-diethyl-m-toluamide
3. Tetrakis(hydroxymethyl)phosphonium sulfate
• Conclusions
2

3. RIWA: who are we?
• Association: water companies that use
river water as source for the production of
drinking water
• Sources: rivers Rhine, Meuse and Scheldt
• Members: supply drinking water to
several millions of consumers
• 530 Mm3/a in NL and 275 Mm3/a in B
3

4. Our mission statement
• The water quality in the rivers Rhine and
Meuse should be such that it can be
purified to drinking water using natural
treatment
Not the same as but in line with
Article 7 Water Framework Directive
• Avoid deterioration of water quality in order
to reduce the level of purification treatment
required in the production of drinking water
4

5. Location of
Meuse and
Rhine river
basins 5

6. Our monitoring programme
• Purpose is twofold:
1. To know the status of the river water quality
2. To detect trends in the river water quality
• RIWA Members monitor their source at
the intake
– To meet regulatory obligations,
– To control the production process, and
– To fulfil RIWA monitoring programme
• RIWA coordinates and reports annually
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7. RIWA Members monitor
their source at intake
Two examples of monitoring points
continuous automatic sampling grab sampling
Keizersveer (Meuse) Nieuwegein (Lek Canal, Rhine Basin)
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8. Our monitoring programme
• We focus on drinking water relevant
substances
– Substances that fail to meet Regulatory Water
Quality Standards
– Substances that breech Target Values from
the European River Memorandum
• We sometimes detect substances that
(could) have been used as a biocide
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9. Our monitoring programme
• Three major concerns
1. Plant Protection Products, Biocides and their
metabolites
• Glyphosate / AMPA major water quality problem
• Glyphosate is considered a PPP, but emissions
originate mostly from use outside agriculture
• AMPA is a metabolite of PPP’s as well as of
coolant additives (phosphonates)
2. New Emerging Substances / Substances of
Emerging Concern
3. Impact of Climate Change
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10. European
River
Memorandum
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11. Biocides in our monitoring
programme
• Who determines that a substance we have
detected was used as a biocide?
– We do not have this specific expertise
• NL: Board for the permission of plant
protection products and biocides (Ctgb)
sends a list of PPPs and Biocides which
are authorised annually
– In return we send Ctgb our monitoring results
over the past 5 years
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12. Biocides in the Netherlands
• Water Quality Standard in NL for PPPs
and Biocides in Surface Water used for
drinking water production is 0.1 μg/L
– WQS exceedances at intake points play a role
in the authorisation process
– Hence our co-operation with Ctgb
• Sometimes multiple uses of substances
– We are unable to distinguish the use as PPP
from the use as a biocide
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13. Biocides detected in rivers
Going back in time to learn for the future
Diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea)
• Major problem due to use as weed killer on
paved areas
– Technicality: this use does not protect any crop but
still it is seen as a PPP
• Caused the longest intake stop ever recorded
back in 1993
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14. 1993
• Intake of water from the River Meuse
was stopped for 7 weeks
– Diuron levels exceeded intake criterion (= 10
times the Water Quality Standard)
– Maximum bridging capacity of reservoirs is
approximately 90 days
14

15. Biocides detected in rivers
Diuron
• The use of the active substance in PPPs was
banned in NL in 1999 / in B in 2002
• Temporary ban in EU in 2007, re-admission in
October 2008
• December 2008: placement on the list
of Priority Substances under WFD
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16. Diuron in Dutch surface
water: average concentrations
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17. Diuron levels in Rhine and
Meuse
0.0
0.2
Concentration in μg/L
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
01/Jan/91
14/Jul/92
25/Jan/94
08/Aug/95
18/Feb/97
01/Sep/98
14/Mar/00
25/Sep/01
08/Apr/03
19/Oct/04
02/May/06
13/Nov/07
26/May/09
07/Dec/10
19/Jun/12
31/Dec/13
Keizersveer (Meuse) Nieuwegein (Rhine Delta) WQS
This peak
originates from
an incident in B
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18. Biocides detected in rivers
Diuron
• Since 1999 no PPP-authorisation in NL
• Currently two Biocides based on Diuron
are authorised in NL
1. ACTICIDE MKX (for use in paint and plaster)
2. MIRECIDE-TF/480.F (for use in paint)
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19. Biocides detected in rivers
DEET (N,N-diethyl-m-toluamide)
• Use as active substance authorised
in 35 biocides in NL / 17 in B
– Various anti-mosquito sticks, rollers,
gels and sprays
• There have always been
detections
– Until recently under WQS
– Now we also see breeches of
WQS 19

20. DEET in Dutch surface water
average concentrations
20

21. DEET levels in the River
Meuse
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
23 October
2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
Luik (M600) Heel (M690) Keizersveer (M865) WQS
Concentration in μg/L
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22. Biocides detected in
the Rhine
THPS (Tetrakis(hydroxymethyl)phosphonium sulfate)
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23. Biocides detected in
the Rhine
THPS (Tetrakis(hydroxymethyl)phosphonium sulfate)
What had happened?
• Treatment of the coolant of the Leibstadt (CH)
Nuclear Power Plant
– 28 June 2011: 15 tonnes of 13% Sodium hypochlorite
• Sodium thiosulfate was used to neutralise unused chlorine
before emitting the coolant in the Rhine
– 30 June 2011: 2.1 tonnes of THPS was added to the
coolant system
• Hydrogen peroxide was added, transforming THPS into
THPO (Tris-hydroxymethylphosphine oxide) before emitting
the coolant in the Rhine 23

24. Biocides detected in
the Rhine
THPS (Tetrakis(hydroxymethyl)phosphonium sulfate)
Drinking water companies in CH, DE and NL were
agitated because
• No information was shared beforehand even though the
company involved did inform the authorities
• There were no analytical methods available to measure
THPS and THPO at the time
• Intakes for drinking water production in CH and DE were
stopped out of precaution
Modelling was performed to estimate concentrations at
intake points, samples were take for future analysis
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25. THPO in the Rhine
Model results vs measurements
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26. Biocides detected in
the Rhine
THPS and THPO
Measured concentrations were significantly lower
than the predictions from the model
• But still well over the 0.1 μg/L
Drinking water companies demanded steps to be
taken to prevent future incidents
• Better information sharing and stricter permits
• International Commission for the Protection of the Rhine
makes inventory of all coolant emissions
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27. Biocides of concern for
drinking water production
27
RIVM Study 601712007/2010
KWR Study BTO 2013.205(s): LC/MS and GC/MS
methods adapted, only irgarol was found (< WQS)

28. Conclusions
• Biocides are currently not a continuous
concern to the production of drinking water
from Rhine and Meuse
– caution is necessary since incidents have occurred
• Concerns about the future, because
– Not all individual substances can be analysed yet
– New techniques are developed and implemented
(2014: method for quaternary ammonium compounds
operational)
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29. Recommendations
• Emissions of coolant into the rivers is an
issue to follow up on
– Besides biocides also other compounds are emitted
eg. anti-foaming agents, anti-corrosion agents
• Emissions have a larger impact under low
flow conditions (especially for the Meuse)
– This should be considered in the permit
– This becomes more important under changing climate
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30. Thank you for your attention!
www.riwa.org
André Bannink
Are there any questions?
@BanninkAndre
My publications
can be found on 30