SUPPORTING INFORMATION

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1 SUPPORTING INFORMATION For Comparative Analysis of Halonitromethane and Trihalomethane Formation and Speciation in Drinking Water: The effects of Disinfectants,, Bromide, and Nitrite Jia Hu a, Hocheol Song b *, and Tanju Karanfil a * a Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC 29625, USA b Korea Institute of Geoscience and Mineral Resources, Daejeon , Korea *Corresponding authors: phone , fax , hsong@kigam.re.kr phone , fax , tkaranf@clemson.edu Submission: September 1, 2009 Revised Manuscript Submitted on: November 16, 2009 Submitted to Environmental Science & Technology 1

2 EXPERIMENTAL UFC Tests. Water samples were buffered by addition of 4 mm sodium bicarbonate and the was further adjusted with HCl/NaOH (1M) solutions. A fresh chlorine stock was prepared daily by diluting sodium hypochlorite (5-6% available free chlorine) before the experiment each time. A monochloramine stock solution was prepared by mixing sodium hypochlorite (5-6% available free chlorine) in an ammonium sulfate solution at a Cl 2 /N mass ratio of 3.5:1 (0.69:1 molar ratio) and 9. Before conducting UFC tests, preliminary demand tests were conducted for each sample to determine the doses of NH 2 Cl and Cl 2 that would provide a total chlorine residual of about 2.0 mg/l for chloramination and a free chlorine residual of 1.0 mg/l for chlorination after one day of contact time. The concentrations of the free chlorine and monochloramine were measured with Standard Method 4500-Cl F (DPD Ferrous Titrimetric Method). Each reactor (65 ml) initially received a stir bar and was completely filled with the test water. Then, a precalculated volume of the water was removed from each reactor, with the volume removed being equal to the volume of the ozone stock solution to be added for ozonation. For the reactors involving only chlorination or chloramination, the removed volume was filled with deionized distilled water (DDW) to yield the same dissolved organic carbon (DOC) concentration as in the ozonated reactors. Ozonation of the sample was achieved by adding varying amount of ozone stock solution ( 30 mg/l) to produce desired ozone concentration. Ozone was produced using a GTC-1B ozone generator (Griffin Technics Inc.) fed with ultra high purity oxygen. A 6 L glass equalization glass tank was placed on the output side of the ozone generator to minimize the effects of fluctuations in ozone production. After the equalization tank, a 1 L gas washing bottle (Tudor Scientific Glass) 2

3 was used to produce the ozone stock solution. While the ozone stock solutions were being produced, the gas washing bottle was placed in an ice bath (~4 ºC) to increase gas solubility. Ozone dose was equal to DOC of the samples (i.e., 1:1 ratio) because this is a typical ratio used in ozonation during water treatment. After the application of ozone, the reactors were mixed for 5 min. prior to the addition of chlorine or chloramine. Ozone concentrations were measured after 5 min contact time to assure that there is ozone residual and ozone was not a limiting factor during the pre-oxidation period. Chlorination and chloramination of samples were accomplished by spiking predetermined amount of chlorine ( 1600 mg/l) and preformed monochloramine ( 800 mg/l) stock solutions, respectively, to achieve desired concentration. The bottles were incubated in a water bath (22 ºC) and the reactions were allowed to occur for 24 hr except those involved chloramination, which were reacted for 72 hr. For each disinfection scenario, duplicate reactors were prepared. Further information can be found in Karanfil et al. (2009). HNMs and THMs Analyses. A 10 ml sample was extracted using 10 ml of methyl tert-butyl ether (MTBE, Sigma), 3 g of sodium sulfate and 1 g of cupric sulfate. The samples were then placed on a shaker table at 300 rpm for 30 min. The MTBE extract was analyzed with a HP 6850 gas chromatograph (GC) equipped with a DB-5 column (J&W Scientific, 30m, 0.25mm, 1.8µm) and an electron capture detector (ECD). HNM standards were obtained from Orchid Cellmark (New Westminster, Canada, CNM 93.6%, DCNM 99+%, BCNM 91.9%, BDCNM 93.9%, DBNM 91.4%, DBCNM 94.1%, TBNM 99+%) and Sigma (TCNM 99+%, BNM 99+%). The GC temperature program used was 35 ºC for 6 min, 30 ºC/min to 190 ºC and hold for 1.5 min. The sample (2 µl) was injected in splitless mode. The carrier and make-up gas were ultra-high purity (UHP) He 3

4 at 2.3 ml/min and UHP nitrogen at 60 ml/min, respectively. The injector temperature was set at 117 ºC in order to minimize the thermal decomposition of HNM species, and the detector temperature was set at 297 ºC. Further information can be found in Karanfil et al. (2009). Bromine Incorporation Factor (n) Bromine incorporation factor, n, is a parameter used to quantify the shift of DBP formation to brominated DBPs with increasing bromide concentration. For example, in case of HNM, n is defined as; n = HNMBr6 (µmol/l)/hnm9 (µmol/l) where HNMBr6 is the sum of the molar concentrations of bromine incorporated in the six brominated HNM species. HNM9 represents the sum of molar concentrations of all nine HNM species HNMBr6 = (BNM*1) + (BCNM*1) + (BDCNM*1) + (DBNM*2) + (DBCNM*2) + (TBNM*3) 4

5 Table S1. HNM formation of CH raw and treated waters Disinfection CNM BNM DCNM BCNM DBNM TCNM BDCNM DBCNM TBNM DHNM THNM HNM HNM/DOC n Method nm nm nm nm nm nm nm nm nm nm nm nm nmol/mg raw Cl 2 6 ND ND ND ND ND <MRL 3.3 ND ND ND O 3 -Cl 2 6 ND ND < MRL ND ND < MRL ND < MRL Cl 2 8 ND ND < MRL ND ND <MRL 3.3 ND ND < MRL O 3 -Cl 2 8 ND ND < MRL ND < MRL < MRL <MRL < MRL treated Cl 2 6 ND ND ND ND ND <MRL 3.2 ND ND ND O 3 -Cl 2 6 ND ND < MRL ND < MRL < MRL <MRL < MRL Cl 2 8 ND ND < MRL ND < MRL <MRL 3.3 < MRL ND < MRL O 3 -Cl 2 8 ND ND < MRL ND <MRL n: bromine incorporation factor ND: Not Detected; no peak was observed on gas chromatographs <MRL: There was a peak but it was below the Minimum Reporting Level of the measurements MRLs (nm): CNM 7.3, BNM 5.0, DCNM 5.4, BCNM 4.0, DBNM 3.2, TCNM 4.3, BDCNM 3.4, DBCNM 2.8, TBNM 2.4 DHNM: dihalogenated HNMs. THNM: trihalogenated HNMs 5

6 Table S2. THM formation of CH raw and treated waters Disinfection CHCl 3 CHCl 2 Br CHClBr 2 CHBr 3 Total THM n Method nm nm nm nm nm - raw Cl ND O 3 -Cl <MRL Cl ND O 3 -Cl <MRL treated Cl <MRL O 3 -Cl <MRL Cl <MRL O 3 -Cl The THM bromine incorporation factors (n) are the molar sum of bromine incorporated into THMs divided by molar sum of THMs, where n ranges from 0 (all chloroform) to 3 (all bromoform). ND: Not Detected; no peak was observed on gas chromatographs <MRL: There was a peak but it was below the Minimum Reporting Level of the measurements MRLs (nm): CHCl 3 2.5, CHCl 2 Br 1.8, CHClBr 2 1.4, CHBr

7 a) THM4 (nmol/l) Ambient (Br/DOC =16 ug/mg) Br/DOC = 50 ug/mg Br/DOC = 100 ug/mg b) THM4 (nmol/l) Ambient (Br/DOC = 33 ug/mg) Br/DOC = 50 ug/mg Br/DOC = 100 ug/mg Figure S1. The effect of bromide on THM4 formation during chlorination of CH a) raw water and b) treated water. 7

8 a) THM4 (nmol/l) Ambient (Br/DOC =16 ug/mg) Br/DOC = 50 ug/mg Br/DOC = 100 ug/mg b) THM4 (nmol/l) Ambient (Br/DOC = 33 ug/mg) Br/DOC = 50 ug/mg Br/DOC = 100 ug/mg Figure S2. The effect of bromide on THM4 formation during ozonation-chlorination of CH a) raw water and b) treated water. 8

9 Table S3. THM formation of CH raw and treated waters at various bromide levels Disinfection CHCl 3 CHCl 2 Br CHClBr 2 CHBr 3 Total THM n-thm4 THNM n-thnm Method nm nm nm nm nm - nm - raw ambient-cl ND Br(50)-Cl <MRL Br(100)-Cl ambient-cl ND Br(50)-Cl <MRL Br(100)-Cl treated ambient-cl <MRL Br(50)-Cl <MRL Br(100)-Cl ambient-cl <MRL Br(50)-Cl Br(100)-Cl n-thm4: bromine incorporation factor of THM4 n-thnm: bromine incorporation factor of THNM ND: Not Detected; no peak was observed on gas chromatographs <MRL: There was a peak but it was below the Minimum Reporting Level of the measurements THNM: trihalogenated HNM 9

10 Table S4. HNM formation of CH waters in the presence of nitrite during chlorination and ozonation-chlorination Disinfection Method CNM BNM DCNM BCNM DBNM TCNM BDCNM DBCNM TBNM DHNM THNM HNM HNM/DOC nm nm nm nm nm nm nm nm nm nm nm nm nmol/mg raw Cl 2 6 ND ND ND ND ND <MRL 3.3 ND ND ND NO 2 -Cl 2 6 ND ND < MRL ND ND ND ND < MRL Cl 2 8 ND ND < MRL ND ND <MRL 3.3 ND ND < MRL NO 2 -Cl 2 8 ND ND < MRL ND < MRL < MRL ND < MRL O 3 -Cl 2 6 ND ND < MRL ND ND < MRL ND < MRL NO 2 -O 3 -Cl 2 6 ND ND < MRL ND ND < MRL ND < MRL O 3 -Cl 2 8 ND ND < MRL ND < MRL < MRL <MRL < MRL NO 2 -O 3 -Cl 2 8 ND ND < MRL ND ND < MRL 1.9 < MRL treated Cl 2 6 ND ND ND ND ND <MRL 3.2 ND ND ND NO 2 -Cl 2 6 ND ND < MRL ND ND <MRL 5.4 < MRL ND < MRL Cl 2 8 ND ND < MRL ND < MRL <MRL 3.3 < MRL ND < MRL NO 2 -Cl 2 8 ND ND ND ND ND ND O 3 -Cl 2 6 ND ND < MRL ND ND < MRL <MRL < MRL NO 2 -O 3 -Cl 2 6 ND ND < MRL ND 2.7 <MRL ND O 3 -Cl 2 8 ND ND < MRL ND <MRL NO 2 -O 3 -Cl 2 8 ND ND ND ND ND ND ND: Not Detected; no peak was observed on gas chromatographs <MRL: There was a peak but it was below the Minimum Reporting Level of the measurements MRLs (nm): CNM 7.3, BNM 5.0, DCNM 5.4, BCNM 4.0, DBNM 3.2, TCNM 4.3, BDCNM 3.4, DBCNM 2.8, TBNM 2.4 DHNM: dihalogenated HNMs. THNM: trihalogenated HNMs. 10

11 Table S5. HNM formation of CH raw water during chloramination and ozonation-chloramination Disinfection Method CNM BNM DCNM BCNM DBNM TCNM BDCNM DBCN TBNM DHNM THNM HNM M nm nm nm nm nm nm nm nm nm nm nm nm 6 O 3 ND ND ND ND ND ND ND ND ND ND ND ND NH 2 Cl ND ND < MRL ND ND < MRL ND ND ND < MRL <MRL < MRL O 3 _NH 2 Cl ND ND < MRL ND ND < MRL 4.1 ND ND < MRL Br (50)_O 3 ND <MRL ND ND ND ND ND ND ND ND ND < MRL Br (100)_O 3 ND < MRL ND ND < MRL ND ND ND ND < MRL ND < MRL Br (50)_NH 2 Cl ND ND < MRL ND ND < MRL ND ND ND < MRL <MRL < MRL Br (100)_NH 2 Cl ND ND < MRL < MRL ND < MRL < MRL ND ND < MRL <MRL < MRL Br (50)_O 3 _NH 2 Cl ND ND < MRL < MRL ND < MRL 5.0 ND ND < MRL Br (100)_O 3 _NH 2 Cl ND ND < MRL < MRL < MRL < MRL 4.6 < MRL < MRL < MRL NO 2 _O 3 ND <MRL ND ND ND ND ND ND ND ND ND <MRL NO 2 _NH 2 Cl ND ND <MRL ND ND < MRL 3.7 ND ND <MRL NO 2 _O 3 _NH 2 Cl ND ND < MRL ND ND < MRL 4.1 ND ND < MRL O 3 ND ND ND ND ND ND ND ND ND ND ND ND NH 2 Cl ND ND < MRL ND ND ND ND ND ND < MRL ND < MRL O 3 _NH 2 Cl ND ND < MRL ND ND < MRL ND ND ND < MRL <MRL < MRL Br (50)_O 3 ND <MRL ND ND ND ND ND ND ND ND ND < MRL Br (100)_O 3 ND < MRL ND ND ND ND ND ND ND ND ND < MRL Br (50)_NH 2 Cl ND ND < MRL ND ND ND ND ND ND < MRL ND < MRL Br (100)_NH 2 Cl ND ND < MRL ND ND ND ND ND ND < MRL ND < MRL Br (50)_O 3 _NH 2 Cl ND ND < MRL < MRL ND < MRL ND ND ND < MRL <MRL < MRL Br (100)_O 3 _NH 2 Cl ND ND < MRL < MRL ND < MRL ND ND ND < MRL <MRL < MRL NO 2 _O 3 ND ND ND ND ND ND ND ND ND ND ND ND NO 2 _NH 2 Cl ND ND <MRL <MRL ND < MRL ND ND ND <MRL <MRL < MRL NO 2 _O 3 _NH 2 Cl ND ND < MRL ND ND < MRL ND ND ND < MRL <MRL < MRL ND: Not Detected; no peak was observed on gas chromatographs <MRL: There was a peak but it was below the Minimum Reporting Level of the measurements MRLs (nm): CNM 7.3, BNM 5.0, DCNM 5.4, BCNM 4.0, DBNM 3.2, TCNM 4.3, BDCNM 3.4, DBCNM 2.8, TBNM 2.4 DHNM: dihalogenated HNMs. THNM: trihalogenated HNMs 11

12 REFERENCES Karanfil, T., Hu, J., Addison, J. A., Jones, D., Song, H., Saglam, A., Formation of Halonitromethanes and Iodotrihalomethanes in Drinking Water and Wastewater Effluents. Water Research Foundation Final Report, Denver, CO, (in preparation). 12