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EPA Drinking Water Regulatory Update (from a Wastewater Perspective) October 2011

EPA Drinking Water Regulatory Update (from a Wastewater Perspective) October 2011. Bruce Macler USEPA Region 9 (415) 972-3569 macler.bruce@epa.gov. Topics (not necessarily in order). Direct impacts Pathogenic microorganisms Nitrate/nitrite NDMA and other nitrosamines

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EPA Drinking Water Regulatory Update (from a Wastewater Perspective) October 2011

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  1. EPA Drinking Water Regulatory Update (from a Wastewater Perspective)October 2011 Bruce Macler USEPA Region 9 (415) 972-3569 macler.bruce@epa.gov

  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 15499-15572 • 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+6cytotoxicity 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 51850-51862 • 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 1st 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 & Terbufossulfone • 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 • 10-6 risk @ 0.7 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; HRL @ 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 <200oC • Henry’s Law constant: > .01 • Analysis with purge/ trap, method 524.3 • 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 7762-7767 (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 11713-11737 • 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 200.8 • Vanadium • Molybdenum • Cobalt • Strontium* • May require both source and distribution system monitoring

  35. Method 300.1 • Chlorate* • Will require collection of chlorination information as well • Gaseous chlorine • Potassium hypochlorite • Sodium hypochlorite

  36. Method 522 • 1,4 Dioxane*

  37. Method 524.3 • 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-b Estradiol • 17-a 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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