Case Study - Occurrence of Non-Regulated Disinfection By-Products from the

Capalaba Region’s Distribution System

Maria José FarréHollie

King, Emmanuelle Filloux, Jurg

Keller, Wolfgang Gernjak

–

AWMCNicole Knight, Kalinda

Watson, Fred Leusch

–

SWRCMichael Bartkow –

Seqwater; Brad Taylor -

Allconnex Water; Paul Burrell –

WGM

Assessment of Regulated and Emerging DBPs in SEQ Drinking Water

Science Forum, 19-20 June 2012

Urban Water Security Research Alliance

What are DBPs and why are they a concern?

•

Disinfection by-product (DBP) formation is an unintended consequence of disinfecting water in order to remove water-

borne pathogens

•

DBP presence in drinking water has been related to bladder cancer and reproductive/developmental disorders

•

DBPs enter in our body through ingestion, inhalation and dermal absorption

•

Stringent regulations for DBP

Chemical disinfectant + natural organic matter = DBPs

12 Regulated DBPs75 Emerging DBPs

DBPs discovered but not quantified

Unknown DBPs 50% in chlorinated

systems>80% when disinfecting with chloramines, ozone

and chlorine dioxide

Organic DBP precursor

Inorganic DBP precursor

Disinfectant

Regulated & emergingDBPs

Natural organic matter,Anthropogenic contaminants

Unintended consequence of disinfecting the water

DBP formation

DBP formation

Organic DBP precursor

Inorganic DBP precursor

Disinfectant

Regulated & emergingDBPs

Natural organic matter,Anthropogenic contaminants

Bromide (Br-), iodide (I-), nitrite (NO2-)

Chlorine, chloramine, chlorine dioxide, ozone

Trihalomethanes (THMs), haloacetic acids (HAA), haloacetaldehydes, halonitromethanes, nitrosamines, etc…

Also pH, temperature, contact time and disinfectant dose affect the formation of DBPs

DBPs USEPA (µg/L) WHO (µg/L)European Union Standards (µg/L)

2011 ADWG (µg/L)

Bromate 10 10 10 20Bromoacetic acid 60 as HAA5

Bromodichloromethane 80 as TTHMs 60 100 as tTHMs 250 as tTHMsBromoform 80 as TTHMs 100 100 as tTHMs 250 as tTHMs

Chlorate 700Chloroform 80 as TTHMs 300 100 as tTHMs 250 as tTHMs

Chlorite 1000 700 800Chloroacetic acid 60 as HAA5 20 150

Dibromochlormethane 80 as TTHMs 100 100 as tTHMs 250 as tTHMsDichloroacetic acid 60 as HAA5 50 100Trichloroacetic acid 60 as HAA5 100Dichloroacetonitrile 20Dibromoacetic acid 60 as HAA5Dibromoacetonitrile 70

N-nitrosodimethylamine 0.1 0.1Trichloroacetaldehyde 20

Cyanogen chloride (as cyanide) 70 80

Regulation

Some of the most toxic DBPs in in-vitro assays are not regulated in drinking water. These are called emerging DBPs

Note: While the US EPA drinking water standards for tTHMs and HAAs are numerically lower than the Australian drinking water guideline values, compliance in the US is defined on the basis of a running annual average of quarterly averages of all samples, whereas compliance is based on single exceedances in Australia

Plewa, M. et al. (2008). ACS Symposium Series

OBJECTIVES OF THE PROJECT

PLs: Maria José

Farré

and Nicole KnightDuration: June 2010-June 2012

Main objectives:

Establishment of an analytical capability to measure emerging DBPs (AWMC)

Evaluate the potential of DBP formation in SEQ (AWMC)

Evaluate the effects of transforming disinfectants in the water grid (AWMC)

Measure emerging and regulated DBPs in South East Queensland (AWMC + SWRC)

Evaluate strategies to remove halogen + organic matter from water (SWRC)

Characterize organic matter in South East Queensland (SWRC)

UWSRA Science Forum 2011 Source water (post coagulation + filtration) * post RO

DOC (mg/L) DON (mg/L) HOCl demand (mg/L)

Molendinar WTP (n=5) 2.7 ±

1.6 0.29 ±

0.09 3 ±

1

Capalaba WTP (n=5) 10.3 ±

5.7 0.41 ±

0.22 9 ±

2

Mt Crosby WTP (n=5) 2.8 ±

0.8 0.21 ±

0.14 4 ±

2

*Tugun desal (n=2) <1.00 n.a 0

filtration

3 days of contact time

Dose=chlorine demand + 2-3 mg/L

pH=7Analysis by GC/ECD

HOCl/ NH2

Cl

Experiments done:•

Chlorine DBPs •

Chloramine DBPs•

Chlorine → chloramine (adding NH4+)

•

Chloramine → chlorine (via breakpoint chlorination -

ie, adding HOCl)•

NDMA /other nitrosamines and NDMA Formation potential•

5 bioassays on different disinfected waters and transformations (Entox)

DBPs individually measured•

4 regulated THMs

•

5 I-THMs•

4 haloacetonitriles

•

1 haloacetaldeyde (CH/trichloroacetaldehyde)•

2 propanones

•

1 halonitromethane (TCNM/chloropicrin)•

5 haloacetic acids

•

5 nitrosamines

Cl Br

Br

Br Br

Br

Br Cl

Cl

Cl

Cl

O

N+

O

O -Cl

ClCl

THMs

DCAN

1,1-DCP TCNM

TCAA

I Cl

Cl

DCIM

HO

OH

Cl

ClClCH

UWSRA Science Forum 2011 Molendinar water Capalaba water Mt Crosby water Tugun desal

combined RO permeate

THMs, HAN, CH, TCNM, HK

Medium-low formation

High formation Medium-low but generates Br-THMs

Negligible formation

NDMA/NDMA FP

<LOD/relatively high (ie, 30 ng/L)

<LOD/ low <LOD/ low <LOD/ low

Non specific toxicity

Effect observed Showed the highest observed effect

Effect observed No effect observed

Reactive toxicity

No effect observed Effect observed No effect observed No effect observed

0

50

100

150

200

250

300

350

Molendinar Capalaba Mt Crosby Tugun Desal

µg/L

Total THMs TBMDBCMBDCMTCM

0

50

100

150

200

250

300

350

Molendinar Capalaba Mt Crosby Tugun Desal

µg/L

Total THMs TBMDBCMBDCMTCM

Capalaba source water contains high concentrations of DBP precursorsBioassays are in agreement with chemical analysis

CapalabaWTP

M11

M13

M14

M10

M8

M22

M17

M16

M21

M23

M19

M29

M33

M52

M51

M50

M38

M42

M45

Redland region sampling plan5th

September 20113rd

October 20117th

November 201121st

November 20116th

December 2011

5 Sampling Events

20 sampling points

Alexandra Hills Reservoir – Blended water (Capalaba and NSI)

Majority Capalaba WTP water

Mix of Capalaba and Alexandra Hills

North Stradbroke Island (NSI) WTP

End of Pipeline

Concentration of THMsAverage of sampling events and range

Alexandra Hills Reservoir – Blended water (Capalaba and NSI)

Capalaba WTP water

Mix of Capalaba and Alexandra Hills

North Stradbroke Island (NSI) WTP

Con

cent

ratio

n µg

/L

Sampling point n DOC

(mg/L) St dev Br-

(µg/L) St dev DON (mg/L) St dev Br-/DOC

(x100)Cap 4 6.0 1.0 53 7 0.32 0.11 0.1M8 5 3.8 0.8 25 4 0.29 0.29 0.1M10 5 2.3 2.1 36 7 0.21 0.08 0.2M11 4 4.9 0.7 51 6 0.29 0.15 0.2M13 5 4.5 1.2 38 6 0.36 0.04 0.1M14 4 4.1 1.4 40 5 0.29 0.08 0.1M16 5 4.9 2.3 41 7 0.33 0.26 0.1M17 4 2.9 0.6 60 8 0.27 0.13 0.3M19 5 1.7 0.6 30 5 0.15 0.12 0.3M21 4 2.5 1.8 30 5 0.11 0.1 0.2M22 2 1.1 0.3 27 5 0.14 0.07 0.4M23 4 2.1 2.5 43 7 0.20 0.18 0.3M29 4 1.0 1.1 66 3 0.11 0.04 1.0M33 2 0.6 0.3 60 2 0.11 0.01 1.6M38 3 2.0 2.2 65 9 0.10 0.03 0.5M42 3 2.0 2.6 70 3 0.09 0.12 0.6M45 3 0.6 0.5 66 1 0.14 0.11 1.5M50 4 0.5 0.4 64 4 0.08 0.1 2.1M51 5 0.8 0.5 59 6 0.15 0.09 1.2M52 3 1.2 0.3 61 2 0.13 0.11 0.8

CapalabaWTP

M11

M13

M14

M10

M8

M22

M17

M16

M21

M23

M19

M29

M33

M52

M51

M50

M38

M42

M45

CapalabaWTP

M11

M13

M14

M10

M8

M22

M17

M16

M21

M23

M19

M29

M33

M52

M51

M50

M38

M42

M45

Br/DOC ratio is important for speciation of DBPs •

Capalaba (ratio x 100) <0.3•

NSI and NSI affected water (ratio x 100) 0.2-2.1

Concentration of THMsAverage of sampling events and range

Alexandra Hills Reservoir –Blended water (Capalaba and NSI)

Majority Capalaba WTP water

Mix of Capalaba and Alexandra Hills

North Stradbroke Island (NSI) WTP

Con

cent

ratio

n µg

/L

Dr Knight to give more details about this effect in the following presentation

Fluorescence Excitation Emission Matrix

Scale 0-300

M11 4x dilution M13 4x dilution

M19 4x dilution M21 2x dilution M22 2x dilution

M50 no dilution M51 no dilution M52 no dilution

Capalaba WTP water

Alexandra Hills Reservoir – Blended water (Capalaba and NSI)

North Stradbroke Island WTP

M14 4x dilution

Capalaba WTP water Mix of Capalaba

and Alexandra Hills

Alexandra Hills Reservoir – Blended water (Capalaba and NSI)

North Stradbroke Island WTP

Fluorescence Regional Integration Analysis

Error bars correspond to the standard deviation

0

50

100

150

200

250

Capalaba Capalaba + NSI NSI

tTH

Ms

(µg/

L)

Plewa, M. et al. (2008). ACS Symposium Series

ADWG

REP i ECref

ECi

TEQ ci

i1

n

REPi

Relative Effect Potency:

Toxic Equivalent Concentrations:

Reference compound: TCM

DBP1/EC50

(M-1) REP

TCM 104 1.0

BDCM 87 0.8

DBCM 187 1.8

TBM 253 2.4

Trihalomethanes (THMs)

25th median and 75th

percentile represented. The whiskers are the maximum and minimum

values. The ret dots are outliers.

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

DCIM BCIM DCIM BCIM

Con

cent

ratio

n (µ

g/L)

Alexandra Hills Reservoir – Blended water (Capalaba and NSI)

Capalaba WTP water

Iodine containing trihalomethanes (I-THMs)

0

0.2

0.4

0.6

0.8

1

1.2

TCM‐EQ (µ

M/L)

Capalaba THMs

Capalaba + NSI THMs

NSI THMs

Capalaba  I‐THMs

CapalabaWTP

M11

M13

M14

M10

M8

M22

M17

M16

M21

M23

M19

M29

M33

M52

M51

M50

M38

M42

M45

Relative Effect Potency of I-THMs vs other DBPs:

DBP 1/EC50

(M-1) REPTCM 104 1.0

BDCM 87 0.8DBCM 187 1.8TBM 253 2.4DCIMDCIM 242242 2.32.3BCIMBCIM 413413 4.04.0DBIMDBIM 526526 5.15.1CDIMCDIM 415415 4.04.0BDIMBDIM 714714 6.96.9TCAN 6250 60.1DCAN 17452 167.8BCAN 118203 1137DBAN 350877 3374

CH 862 8.3TCNM 189 1.8

Haloacetonitriles (HANs)

0

2

4

6

8

10

12

TCAN DCAN BCAN DBAN

HAN

s (µ

g/L)

Capalaba

0

10

20

30

40

50

TCM

-TEQ

(µM

/L)

Capalaba

Capalaba + NSI

NSI

25th median and 75th

percentile represented. The whiskers are the maximum and minimum values. The ret dots are outliers.

DBP1/EC50

(M-1) REP

TCAN 6250 60.1

DCAN 17452 167.8

BCAN 118203 1137

DBAN 350877 3374 TEQ ci

i1

n

REPi

N

ClClCl

trichloroacetonitrile

 (ug/L)monochloroacetic acid dichloroacetic acid trichloroacetic acid bromochloroacetic acid monobromoacetic acid dibromoacetic acid

M8 <10 17 55 <10 <10 <10M10 <10 <10 21 <10 <10 <10M11 <10 <10 13 <10 <10 <10M13 <10 15 36 <10 <10 <10M14 <10 13 38 <10 <10 <10M16 <10 <10 21 <10 <10 <10M17 <10 <10 <10 <10 <10 <10M19 <10 15 19 <10 <10 <10M21 <10 17 25 10 <10 <10M22 <10 19 25 11 <10 <10M23 <10 <10 <10 <10 <10 <10M29 <10 <10 <10 <10 <10 <10M33 <10 <10 <10 <10 <10 <10M38 <10 <10 <10 <10 <10 <10M42 <10 <10 <10 <10 <10 <10M45 <10 <10 <10 <10 <10 <10M50 <10 <10 <10 <10 <10 <10M51 <10 <10 <10 <10 <10 <10M52 <10 <10 <10 <10 <10 <10cap WTP <10 28 44 <10 <10 <10

Haloacetic AcidsSampling #4 21/11/2011

DBPs USEPA (µg/L) WHO (µg/L)2011 ADWG

(µg/L)Bromoacetic acid 60 as HAA5Chloroacetic acid 60 as HAA5 20 150

Dichloroacetic acid 60 as HAA5 50 100Trichloroacetic acid 60 as HAA5 100Dibromoacetic acid 60 as HAA5

Note: While the US EPA drinking water standards for tTHMs and HAAs are numerically lower than the Australian drinking water guideline values, compliance in the US is defined on the basis of a running annual average of quarterly averages of all samples, whereas compliance is based on single exceedances in Australia

O

OH

Cl

Cl

dichloroacetic acid

O

OHCl

Cl

Cl

trichloroacetic acidO

OH

Cl

Br

bromochloroacetic acid

CapalabaWTP

M11

M13

M14

M10

M8

M22

M17

M16

M21

M23

M19

CapalabaWTP

M11

M13

M14

M10

M8

M22

M17

M16

M21

M23

M19

N

O

NO

nitrosomorpholine

•

End of the pipe sampling points tested•

No NDMA or other nitrosamines (> 5ng/L LOD)

•

NDMA FP at Capalaba WTP = 11.4 ±

3.4

ng/L

NDMA and other N-nitrosamines

NDMA has been recently included in the ADWG at 100 ng/L. NDMA formation potential (FP) gives an indication of the NDMA precursors in a specific water (7 days, pH 7, chloramines)

0

0.5

1

1.5

2

CH TCNM 1,1-DCP 1,1,1-TCP

Con

cent

ratio

n (µ

g/L)

NSI

0

5

10

15

20

CH TCNM 1,1-DCP 1,1,1-TCP

Con

cent

ratio

n (µ

g/L)

Capalaba

0

5

10

15

20

CH TCNM 1,1-DCP 1,1,1-TCP

Con

cent

ratio

n (µ

g/L)

Capalaba + NSI

Watch out the scale!

25th median and 75th

percentile represented. The whiskers are the maximum and minimum values. The ret dots are outliers.

Other DBPsADWG ADWG

N+

O

O-Cl

ClCl

trichloronitromethane

Conclusions •

All regulated DBPs were measured below ADWG values in all analysed samples across the Capalaba region (including samples from North

Stradbroke Island)

•

THM speciation followed the order TCM>BDCM>DBCM>TBM in sampling points providing water from Capalaba; and DBCM>BCDM>TBM>TCM in waters blended with NSI water as a result of different Br/DOC ratios (see next presentation)

•

HANs were measured at relatively high concentrations for locations serviced primarily by Capalaba WTP. Even though they were measured below WHO limits, we recommend investigating possibilities to control the formation of HANs at the drinking WTP as they are suspected to be more toxic than carbon-based regulated DBPs

•

NDMA was not detected above the LOD. NDMA formation potential of source water at the Capalaba WTP was 11.4 ±

3.4

ng/L, which is also

well below the ADWG value (i.e., 100

ng/L)

Urban Water Security Research Alliance

THANK YOU

www.urbanwateralliance.org.au