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EPA Drinking Water Regulatory Update (from a Wastewater Perspective) October 2011 Bruce Macler USEPA Region 9 (415) 972-3569

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Presentation on theme: "EPA Drinking Water Regulatory Update (from a Wastewater Perspective) October 2011 Bruce Macler USEPA Region 9 (415) 972-3569"— Presentation transcript:

1 EPA Drinking Water Regulatory Update (from a Wastewater Perspective) October 2011 Bruce Macler USEPA Region 9 (415)

2 Topics (not necessarily in order)  Direct impacts  Pathogenic microorganisms  Nitrate/nitrite  NDMA and other nitrosamines  Other disinfection byproducts  Pesticides, pharmaceuticals, etc  Indirect impacts  Nutrients  Blue-green algae  Perhaps of personal interest  Hexavalent chromium  Perchlorate  Arsenic

3 EPA DW Regulatory Status  Proposed (and closed)  Total Coliform Rule revisions  6-Year Review candidates for revision  Unregulated Contaminant Monitoring Rule 3  In development  Contaminant Candidate List 3 regulatory determinations  Perchlorate  Carcinogenic VOCs  Lead and Copper Rule revisions

4 6-Year Review Status  Candidates for revision announced on March 29, 2010  FR 75, #59, pp  Acrylamide and epichlorohydrin  Treatment technique approach  Trichloroethylene and tetrachloroethylene  Lower PQLs allow lower MCLs  Fluoride may be considered independently  Arsenic, nitrate/nitrite, chromium not reconsidered this time

5 Acrylamide, Epichlorohydrin  Both occur as left-over monomer in treatment polymers  Treatment technique regulation  Comply by certification from supplier  6-year Review revision decision  Levels are lower now, so can  Probably will comply as before  Workgroup not yet established

6 Fluoride News  EPA released a new health and exposure document Jan 7, 2011  New RfD at 0.08 mg/kg/d for severe dental fluorosis (~0.8 mg/L for children <6yrs)  Began reviewing fluoride MCL (4 ug/L) with respect to this (off cycle from 6-year Review)  CDC revised its recommended exposure level to 0.7 mg/L  Continues to support fluoridation for all  Can be a bit above or below 0.7 mg/L  No harm seen < 2 mg/L

7 Chromium  Trivalent chromium (Cr +3 ) is a nutrient  Hexavalent chromium (Cr +6 ) is toxic  CA OEHHA has a revised PHG at 0.02 ug/L for hexavalent chromium  Considers hexavalent chromium carcinogenic  EPA has its risk assessment out for review  Number is about the same as OEHHA’s  But EPA considering new data on Mode of Action of carcinogenicity

8 Cr +6 Mode of Action???  Mode of Action (MOA) describes how something could be toxic  For carcinogens, some can damage DNA, chromosomes directly (genotoxicity)  Some carcinogens kill cells; healing process can trigger cancer (cytotoxicity)  CA OEHHA considers Cr +6 primarily genotoxic  Other data indicate that Cr +6 cytotoxicity dominates at lower exposures

9 Regulatory Changes for Chromium?  Federal MCL is 100 ug/L, CA is 50 ug/L  Based on general toxicity, not cancer  Essentially a hexavalent chromium MCL  Trivalent chromium is a necessary nutrient  CA DPH required to do hexavalent chromium- specific MCL  Cancer assessment points to a downward revision  But 5x less risk than for arsenic  Could get occurrence info from UCMR3  Treatment and costs are a big deal  City of Glendale treatment project is significant

10 Arsenic  Arsenic MCL currently at 10 ug/L  NAS (and OEHHA) risk assessment says it’s 15 x more toxic than thought  ~1% cancer risk at 50 ug/L  Relatively expensive to treat  High O&M costs  Political push back

11 Nitrate/ Nitrite  Pacific Institute issued report on nitrate problems in San Joaquin Valley  Nitrate (nitrite, really) can lead to methemoglobinemia in infants  Very rare, though (ave 3 cases/year in US)  Often not DW related  Usually related to diarrhea  Not an issue for adults at DW levels  Cancer data equivocal  Nitrosamines > nitrite > nitrate

12 Contaminant Candidate List 3  Final list published in Federal Register on October 8, 2009  FR 74, #194 pp  116 CCL 3 members  12 microbial pathogens  104 chemicals or chemical groups  N-nitroso compounds are prominent  Nine hormones  Blue-green algal toxins  Rest mostly “usual suspect” VOCs, metals, pesticides

13 CCL3 Regulatory Determinations  EPA workgroup determining which may be suitable (or not) for regulation  UCMR 1 & 2 and other data being used for occurrence and exposure estimates  All available health information being collected for risk assessments  List first cut down to 32  Based on availability of data  Final determinations expected 2012

14 Current CCL3 Data Availability  Most listed chemical contaminants (69) lack adequate occurrence information  Some don’t even have suitable methods  Most (75) lack adequate health effect information  A few (32) may have both  These being reviewed for 1 st cut  No listed microorganism has adequate risk or occurrence data

15 Possibilities for Decisions  Some may go forward for regulations  Nitrosamines, individually or grouped  1,2,3-trichloropropane, chlorate, strontium  Some may be dropped as not a DW problem  1,3 Dinitrobenzene  Dimethoate  RDX  Terbufos & Terbufos sulfone  Others may need more information

16 Unregulated Contaminant Monitoring Rule 2 Results  UCMR 2 data mostly in  NDMA detected at ~25% of PWSs  Chloraminated SW>chlorinated SW> chloraminated GW>chlorinated GW  Some other nitrosamines rarely found  Very few pesticide hits  No flame retardant hits  Data are influencing CCL3 cut-down

17 N-Nitroso Dimethylamine  NDMA is a known carcinogen  ng/L  Many other nitrosamines have similar risks  Formed from chlorination or chloramination of wastewater  UCMR 2 shows 25% of systems affected  Controversy over relative contributions from food vs water  Hot prospect, singly or as “nitrosamines”

18 Other Possibilities  1,2,3- Trichloropropane  Mutagenic carcinogen  Likely pulled into carcinogenic VOCs reg  Chlorate  DBP  Thyroid effects; 210 ug/L  Strontium  Competes with calcium in bone  HRL for child ~ 1700 ug/L

19 1,4-Dioxane  Considered a carcinogen  Revised EPA IRIS risk assessment estimates risk at 0.4 ug/L  Occurrence data sparse  Likely lack enough information to go forward now

20 Perfluoro Octanoic Acid (C8) Perflurooctane Sulfonate  Used in making Teflon and related products  Extremely persistent  Occurrence largely unknown  Provisional Health Advisory  PFOA = 0.4 ug/L  PFOS = 0.2 ug/L  General effects on liver, growth, development  Lack enough information to go forward now

21 CCL3 Pharmaceuticals  One antibiotic (erythromycin) and nine estrogens were added to the CCL3  Currently lack occurrence data  Lack health effects information for exposures at environmental levels  EPA’s current take is that there is no evidence that pharmaceuticals and personal care products in the environment cause human health effects  Environmental levels typically <1/1,000,000 of therapeutic dose

22 Estrogens in DW  Recent report showed that natural estrogens are far more prevalent than synthetic pharmaceutical estrogens  Wise, O’Brien and Woodruff (2011) ES&T 45:51-60  Pregnant women > women > men > synthetics  Cows and pigs >> people

23 EPA Drinking Water Strategy  The EPA Administrator announced her DW Strategy actions on February 2, 2011  Regulate perchlorate  Regulate TCE, PCE, and possibly other carcinogenic VOCs as a group  Possibly revise existing MCLs for benzene, carbon tetrachloride, 1,2-dichloroethane, 1,2- dichloropropane, dichloromethane, vinyl chloride  Possibly regulate aniline, benzyl chloride, 1,3- butadiene, 1,1-dichloroethane, nitrobenzene, methyl oxirane, 1,2,3-trichloropropane, urethane

24 Currently Regulated Carcinogenic VOCs  Besides TCE and PCE, EPA has MCLs for benzene, carbon tetrachloride, 1,2- dichloroethane, 1,2-dichloropropane, dichloromethane, vinyl chloride  Dichlorobromopropane (DBPC) and ethylene dibromide (EDB) may also be reconsidered  During the last 6-year review, EPA passed on revising these as “not worth the hassle” (too little benefit for the cost to change)

25 Unregulated cVOCs  From the CCL3, aniline, benzyl chloride, 1,3-butadiene, 1,1-dichloroethane, nitrobenzene, methyl oxirane, 1,2,3- trichloropropane, urethane  1,1,1,2 tetrachloroethane, 1,1,2,2 tetrachloroethane other possibilities

26 What is a VOC?  No clear definition or agreement  High vapor pressure, low water solubility  Boiling point <200 o C  Henry’s Law constant: >.01  Analysis with purge/ trap, method  Air stripped (PTA) with >90% efficiency

27 What is a VOC?  These criteria would likely eliminate aniline, benzyl chloride, nitrobenzene, methyl oxirane, 1,2,3-trichloropropane, urethane  Could eliminate 1,2,3-trichloropropane, 1,1,2,2 tetrachloroethane, DBCP

28 cVOC Regulation?  Interest in regulating all these cVOCs as a group for ease and cost savings  Common analytical method  Common treatment  Unclear what this rule would look like  Treatment technique?  Also non-carcinogenic VOCs to consider?  Workgroup just started  Will be awhile….

29 Perchlorate Regulatory Determination  Administrator Jackson announced that EPA would regulate perchlorate on Feb 2, 2011  FR 76 n 29, pp (Feb 11, 2011)  EPA regulatory workgroup established  Examining risks in detail  Working up occurrence and exposure data  Considering treatment approaches and costs  MCLG and possible MCLs will get vetted with respect to benefits and costs  A proposed MCL still a ways off

30 Perchlorate: Health Concerns  Health concerns are for damaged thyroid and brain development in fetuses and infants  Perchlorate interferes with iodide uptake  ~20% of women are deficient in iodide  EPA has reconsidered perchlorate risks to focus on infants and toddlers, as well as pregnant women  Risks run from 1-5 ug/L  CA OEHHA proposed lower PHG on 1/7/11 at 1 ug/L  Based on infants  (6 ug/L level was for pregnant women)

31 Blue-Green Algae  Nutrients appear to be contributing to algal blooms  Cause problems for DW treatment  Daily pH shifts  Filtration problems  Taste and odor complaints  Some species produce toxins sometimes  Not easy to predict  Seems like there are more lately

32 Blue-Green Woes  GI upsets from oral ingestion  Rashes and allergic reactions from dermal exposure  Headaches, fever, fatigue  Poisoning from toxins  Microcystis: microcystin  Liver damage  Anabaena: anatoxin-a  Neurological damage  Can be lethal to dogs

33 UCMR 3  UCMR 3 list proposed March 3, 2011  FR 76, #42, pp  List of methods and chemicals as previously described  Implementation much like UCMR 2  Took comment on substituting hexavalent and total chromium (Method 218.6) for one of the proposed methods  Most responders said yes

34 Method  Vanadium  Molybdenum  Cobalt  Strontium*  May require both source and distribution system monitoring

35 Method  Chlorate*  Will require collection of chlorination information as well  Gaseous chlorine  Potassium hypochlorite  Sodium hypochlorite

36 Method 522  1,4 Dioxane*

37 Method  1,1 Dichloroethane  1,2,3 Trichloropropane*  1,3 Butadiene  Chloromethane  Bromochloromethane  Bromomethane  Propylbenzene  Chlorodifluoromethane (Freon 22)  sec Butylbenzene**

38 Method 537  Perfluoro octane sulfonic acid (PFOS)*  Perfluoro octanoic acid (PFOA)*  Perfluoro nonanoic acid (PFNA)  Perfluoro hexane sulfonic acid (PFHxS)  Perfluoro heptanoic acid (PFHpA)  Perfluoro butane sulfonic acid (PFBS)

39 Method 539  Estriol (16-hydroxy-17-estradiol)  17-  Estradiol  17-  Ethynylestradiol  Equilenin  Equilin  Testosterone  4-Androstene-3,17-dione

40 Finally, Funding  The deficit is the big issue in DC  House, especially, wants to cut EPA  But State Revolving Funds help locally  Likely to stay funded about the same  Streamlining the process desired  No Congressional earmark projects  Apparently  Maybe through the Corps of Engineers  Will be lean for travel and outreach

41 Final Thought: Drinking water from a public supply is about the safest thing you do 41


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