USEPA is proposing 30 currently unregulated contaminants for monitoring in water systems, and submitting this proposal for public comment.
As part of its commitment to implement sensible protections of drinking water for communities across the country, and as required by the Safe Drinking Water Act, the US Environmental Protection Agency (EPA) is proposing 30 currently unregulated contaminants for monitoring in water systems, and submitting this proposal for public comment. The comment period will allow the public and other stakeholders to provide input on the selection of new contaminants for monitoring, and will help determine the best path forward as the EPA seeks to collect data that will inform future decisions about how best to protect drinking water. “Ensuring clean and safe drinking water for all Americans is a top priority for EPA,” said Nancy Stoner, acting assistant administrator for EPA’s Office of Water.
EPA currently regulates more than 90 contaminants in drinking water
“In keeping with the Safe Drinking Water Act, we are submitting for public comment and input our proposed next round of currently unregulated contaminants for monitoring. Learning more about the prevalence of these contaminants will allow EPA to better protect people’s health.”
Under the authority of the Safe Drinking Water Act, EPA currently regulates more than 90 contaminants in drinking water. To keep drinking water standards up-to-date with emerging science, the Safe Drinking Water Act requires that EPA identify up to 30 unregulated contaminants for monitoring every five years. This current proposal is the third Unregulated Contaminant Monitoring Regulation (UCMR 3) and includes requirements to monitor for two viruses and 28 chemical contaminants that could be present in drinking water and do not currently have health-based standards.
EPA is requesting public comment on the proposed list of 30 contaminants until May 2, 2011. Following the public comment period, EPA will consider this important input before the list is scheduled to be finalised in 2012, with sampling to be conducted from 2013 to 2015. Sampling will take place at all systems serving more than 10,000 people and at a representative sampling of systems serving less than 10,000 people.
UCMR 3 Proposed Contaminants and Corresponding Analytical Methods
Assessment Monitoring (List 1)
| Contaminant | CAS Registry Number | Minimum Reporting Level | Analytical Methods |
|---|---|---|---|
| Hormones | EPA 539 | ||
| 17-β-estradiol | 50-28-2 | 0.0004 µg/L | |
| 17-α-ethynylestradiol (ethinyl estradiol) | 57-63-6 | 0.0009 µg/L | |
| 16-α-hydroxyestradiol (estriol) | 50-27-1 | 0.0008 µg/L | |
| equilin | 474-86-2 | 0.004 µg/L | |
| estrone | 53-16-7 | 0.002 µg/L | |
| testosterone | 58-22-0 | 0.0001 µg/L | |
| 4-androstene-3,17-dione | 63-05-8 | 0.0003 µg/L | |
| Volatile Organic Compounds | EPA 524.3 | ||
| 1,2,3-trichloropropane | 96-18-4 | 0.03 µg/L | |
| 1,3-butadiene | 106-99-0 | 0.1 µg/L | |
| chloromethane (methyl chloride) | 74-87-3 | 0.2 µg/L | |
| 1,1-dichloroethane | 75-34-3 | 0.03 µg/L | |
| n-propylbenzene | 103-65-1 | 0.03 µg/L | |
| bromomethane (methyl bromide) | 74-83-9 | 0.2 µg/L | |
| sec-butylbenzene | 135-98-8 | 0.04 µg/L | |
| chlorodifluoromethane (HCFC-22) | 75-45-6 | 0.08 µg/L | |
| bromochloromethane (halon 1011) | 74-97-5 | 0.06 µg/L | |
| Synthetic Organic Compounds | EPA 522 | ||
| 1,4-dioxane | 123-91-1 | 0.07 µg/L | |
| Metals | EPA 200.8 Rev 5.4, ASTM D5673-10, Standard Methods 3125 (1997) | ||
| vanadium | 7440-62-2 | 0.2 µg/L | |
| molybdenum | 7439-98-7 | 1 µg/L | |
| cobalt | 7440-48-4 | 1µg/L | |
| strontium | 7440-24-6 | 0.3 µg/L | |
| Oxyhalide Anion | EPA 300.1, ASTM D6581-08, Standard Methods 4110D (1997) | ||
| chlorate | 14866-68-3 | 20µg/L | |
| Perfluorinated Compounds | EPA 537 Rev 1.1 | ||
| perfluorooctane sulfonate (PFOS) | 1763-23-1 | 0.04 µg/L | |
| perfluorooctanoic acid (PFOA) | 335-67-1 | 0.02 µg/L | |
| perfluorononanoic acid (PFNA) | 375-95-1 | 0.02 µg/L | |
| perfluorohexane sulfonic acid (PFHxS) | 355-46-4 | 0.03 µg/L | |
| perfluoroheptanoic acid (PFHpA) | 375-85-9 | 0.01 µg/L | |
| perfluorobutane sulfonic acid (PFBS) | 375-73-5 | 0.09 µg/L |
EPA reviewed contaminants that had been targeted through existing prioritisation processes, including previous UCMR “reserved” contaminants (i.e., those contaminants for which analytical methods were not yet available), and the Contaminant Candidate List (CCL). Additional contaminants were identified based on current research on occurrence and health effect risk factors. Pesticides that were not registered for use in the United States, contaminants that did not have an analytical reference standard, and contaminants whose analytical methods were not ready for use were removed from the list. EPA further prioritised the remaining contaminants based on more extensive health effects evaluations by the Office of Water’s Office of Science and Technology. These procedures for evaluating health effects were developed to support the ranking of contaminants for future CCLs.
EPA also proposes to monitor for enterovirus and norovirus in UCMR 3.
