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Accessing Unregulated Contaminant Monitoring DataEPA is currently receiving data related to monitoring of unregulated
contaminants from public water systems (PWSs) complying with the Unregulated
Contaminant Monitoring Regulation (UCMR). EPA uses data generated by
the UCMR to evaluate and prioritize contaminants on the Drinking Water
Contaminant Candidate List, a list of contaminants EPA is considering
for possible new drinking water standards. Additional information on
the rule is available on the UCMR main page. To the extent that data reported to EPA (and included in this table) includes positives in source water which was subsequently treated, such data are not expected to be used in the final analysis of national exposure. Caution should be used in any interpretation of the subject data, since this table contains only a subset of the entire set of data expected. (EPA expects additional data to be reported by PWSs during 2004 and will be periodically adding such data to the table.) It should also be clarified that these results are subject to corrections following further review on the part of the analytical laboratory, the public water system, the State or the U.S. EPA. Data you can download are available in MS Excel Pivot Tables. They will be periodically uploaded to include the latest data. Two separate Pivot Table files are presented below, one for the UCMR List 1 and List 2 chemical monitoring data, a second includes the UCMR List 2 microbial monitoring data for the genus Aeromonas. An information sheet is also available which further explains the occurrence data collected for the genus Aeromonas. About MS Excel PivotTables® To use these tables you'll need MS Excel 97 or later. Detailed instructions
are available for downloading, and summary instructions are included
in each PivotTable. No prior knowledge of spreadsheets is required.
Data included in UCMR PivotTable® This PivotTable contains information on EPA reviewed UCMR sample results. Any or all of the following facts for a contaminant-
-can be categorized by any combination of the following water system attributes:
-or any combination of the following sample attributes:
Details on these attributes are provided in the PivotTable. You can double-click on any data cell to obtain PWS-level and sample-level information. Aeromonas detection: what does it mean? 1. What is Aeromonas? Aeromonas is a genus of bacteria that is ubiquitous in the environment. It is present in all types of water worldwide as well as food and soil. There are approximately 16 different species in this genus, the best known of which is Aeromonas hydrophila. Physiologically, Aeromonas are similar to bacteria in the coliform group and can be isolated from similar environments. 2. Where do Aeromonas come from? Aeromonas are commonly isolated from a variety of aquatic environments, including freshwater, estuarine, brackish, and salt waters. Aeromonas is a normal part of the microflora found in these waters, and its presence does not indicate the water has been polluted. These organisms have also been isolated from a variety of foods, including red meats (beef, pork, lamb), poultry, produce, fish, and shellfish. 3. Do Aeromonas cause human disease? Some members of this group of bacteria have been implicated in human disease, although not all strains appear to be pathogenic to humans. Aeromonas infections are typically acquired through two routes, either through ingestion or through exposure of open wounds. The primary clinical diseases from Aeromonas infections are gastroenteritis and bacterial septicemia. Aeromonas-related gastroenteritis is generally a self-limiting watery diarrhea lasting a few days to a few weeks. In individuals with weakened or impaired immune systems, this diarrhea can be chronic and severe (meaning a significant loss of water from the body.) Aeromonas septicemia (a serious condition where bacteria are present throughout the body) generally occurs from wound infections or from gastroenteritis in individuals with weakened immune systems. Aeromonas infections are treatable with antibiotics. 4. Who can get Aeromonas infections? It appears that all people are susceptible to gastroenteritis caused by Aeromonas, although it is most frequently observed in young children (under 5 years of age) and older adults (over 60 years of age). People with compromised immune systems and individuals suffering from leukemia, carcinoma, diabetes, hepatitis, and cirrhosis or those being treated with immunosuppressive drugs or who are undergoing cancer chemotherapy may be susceptible to systemic infections caused by Aeromonas. The Centers for Disease Control and Prevention (CDC) states that the frequency of Aeromonas infections in the United States is unknown and that most cases have been sporadic, individual cases rather than associated with large outbreaks. 5. What is the EPA doing about Aeromonas? Because these bacteria are common in natural waters and because it is generally accepted that some strains of Aeromonas can be pathogenic to humans, the U.S. EPA conducted occurrence monitoring for Aeromonas bacteria in selected drinking water utilities in 2003. Currently, the U.S. EPA is evaluating the data received from this monitoring and is identifying the species of Aeromonas isolated throughout this monitoring period. This information will be used in a risk assessment evaluation to determine whether Aeromonas bacteria should be proposed for regulation in drinking water. 6. How do Aeromonas get into the distribution system? As stated above, Aeromonas occur naturally in freshwaters. Such waters are frequently used as raw sources for treated drinking water. In general, Aeromonas bacteria are killed by the levels of chlorine disinfection used in water treatment facilities. Aeromonas associated with particles in raw waters may evade treatment/disinfection and so enter a distribution system in this manner. A break in a distribution system pipe may also allow untreated water/sewage to enter a system. Once in the system the bacteria may find environments conducive to their survival, especially when temperature and nutrient levels are elevated and when chlorine residuals are low (e.g. in the remote parts of the distribution system and in biofilm material on the inside of pipes). 7. What do I do now? Does my utility have to report this information to the consumers? YES. The Consumer Confidence Report (CCR) Rule requires community water systems (CWSs) to report unregulated contaminant monitoring results whenever such contaminants are detected. If your public water system (PWS) has not had any detections, no CCR reporting requirements apply, but Public Notification (PN) Rule requirements, declaring that the data are available, must still be met (see last paragraph below). The CCR is an annual drinking water quality report that gives PWS customers fundamental information about their drinking water. The centerpiece of the CCR is a table displaying the levels of detected contaminants, including unregulated contaminants, in finished water. For each detected unregulated contaminant, including Aeromonas, the table must display the average of any monitoring results from the year and the range of detections. A PWS may briefly explain in the CCR why it is monitoring for unregulated contaminants. The explanation may read as follows:
EPA has published the guidance document Preparing Your Drinking Water Consumer Confidence Report (EPA 816-R-99-002, March 1999) to assist providers in preparing CCRs. The Agency also has developed the CCR writer, a computer program to help water suppliers create their consumer confidence reports. Both are available at www.epa.gov/safewater/ccr1.html. In addition to CCR requirements, PWSs must also meet the requirements of the Public Notification (PN) Rule. This regulation applies to all PWSs, and requires those PWSs that are subject to the UCMR to notify the public that unregulated contaminant monitoring results are available. EPA’s Public Notification Handbook (EPA 816-R-00-010, June 2000) provides useful information for PWS operators on how to write and distribute effective public notices. The Handbook is available at www.epa.gov/safewater/pn.html. For more information: Embrey, M.A. 2002. Aeromonas hydrophila (and other pathogenic species) in drinking water. In M.A. Embrey, R.T. Parkin, and J.M. Balbus (ed.), Handbook of CCL Microbes in Drinking Water. American Water Works Association: Denver, CO. World Health Organization. 2002. Guidelines for drinking water quality, Addendum: Microbiological agents in drinking water, 2nd Edition, Aeromonas. Current as of August 25, 2003. (PDF 106 KB) For questions, please contact:
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