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THE DEFINITION OF CLEAN The History of Safe Drinking Water in the United States Beam, Longest and Neff INTRODUCTION Since the creation of early, crude drinking water systems, drinking water treatment technologies, drinking water regulations and safe drinking water definitions have continued to evolve. The evolution of water treatment technologies and regulations was spurred by new developments in analytical chemistry technologies. As analytical chemistry technologies, such as gas chromatography and high performance liquid chromatography, were coupled to mass spectrometers, detection of a wider range of chemical classes of contaminants (at detection levels in the parts per trillion (ng/L) range) became possible. Thus, the community’s understanding about the types of harmful substances present in our water supply has risen. This paper presents a brief overview of early water treatment systems, the evolution of Safe Drinking Water Act (SDWA) regulations, the narrowing of the definition of clean water and a forecast of future drinking water regulations. Copyright © 2014 Beam, Longest and Neff, LLC. All Rights Reserved. 2 EARLY WATER DISTRIBUTION SYSTEMS The first municipal drinking water delivery system in the United States went into operation in 1799 in Philadelphia1. By today’s standards, the initial water systems were crude. Disinfection was non-existent and distribution systems were made from wooden pipes like the ones shown below. Wooden water pipes from early 1800s, unearthed last year in lower Manhattan (Photo by Joan Oeismar, with permission) Wooden pipes were used to build early water distribution systems. EARLY WATER FILTRATION & DISINFECTION SYSTEMS The use of sand filtration was the beginning of efforts to remove undesirable contaminants from water. Sand filtration was not practiced in the United States until the 1890’s. The first use of chlorine for disinfection was in Jersey City, New Jersey in 19082. Prior to disinfection practices, outbreaks of cholera and typhoid fever occurred frequently with devastating effects; the frequency of outbreaks decreased once chlorination was established. Filtration experiments began as early as the 17th century, but the first use of sand filters for drinking water production did not occur until 1829 in London3. While sand filtration and chlorine disinfection were effective in reducing turbidity and bacteria in the water, thereby reducing cholera outbreaks, it was much later in 1993 that these same technologies failed to protect human health in Milwaukee. Source: http://esf.edu/ere/endreny/GICalculator/SandFilterIntro.html 3 MILWAUKEE’S FILTRATION FAILURE “The Worst Outbreak in US History” If not properly operated, bacteria, viruses, Cryptosporidium and Giardia (protozoa) can pass through sand filters. Unlike bacteria and viruses, Cryptosporidium is not effectively treated by chlorinating drinking water. In the worst outbreak in US history, Cryptosporidium passed through Milwaukee’s Howard Avenue Water Treatment Plant and contaminated the City’s drinking water supply. Approximately 400,000 people became ill with Cryptosporidiosis, killing approximately 100 people at the time4. This tragic event resulted in a flurry of drinking water regulations that are referred to as the Microbial/Disinfection Byproducts Cluster. CRYPTOSPORIDIOSIS A protozoan infection found in animal or human feces, causing fever and severe digestive issues. The image on the left is an example of what Cryptosporidium look like after they are extracted from the water. They are only visible under a microscope and have an apple green fluorescence. THE EVOLUTION OF DRINKING WATER REGULATIONS As additional information was learned about germs, filtration and disinfection began to be implemented in the late 19th and early 20th centuries, and regulations regarding the safety of potable water were also beginning to be developed. In 1914, the US Public Health Service established a regulation for coliform bacteria. It was another 60 years before the US would have a Safe Drinking Water Act. The Safe Drinking Water Act regulation of 1974 was limited to 23 microbiological and inorganic contaminants and interim standards for trihalomethane disinfection byproducts (additional contaminants became regulated in 1986). COLIFORM BACTERIA Commonly used indicator of bacteria for the quality of water and foods. As mentioned above, the outbreak of Cryptosporidiosis in Milwaukee ushered in modern drinking water regulations. These included the Information Collection Rule, Stage 1 and Stage 2 Disinfectants/Disinfection Byproducts Rules, the Interim Enhanced Surface Water Treatment Rule, Long Term 1 and Long Term 2 Enhanced Surface Water Treatment Rules and the Ground Water Rule. These regulations were called the Microbial/Disinfection Byproducts Cluster. MODERN DRINKING WATER REGULATIONS & CONTAMINANTS The two most important events that led to a greater focus on the definition of clean drinking water after the initial 1974 Safe Drinking Water Act, were the amendments to the Safe Drinking Water Act in 1996 and the Microbial/Disinfection Byproducts Cluster regulations. Among other requirements, the 1996 amendments directed EPA to evaluate unregulated and “emerging” contaminants. EPA was required to identify up to 30 contaminants every five years and mandate drinking water testing for the selected contaminants from a sample of public water supplies across the nation. There have been three Unregulated Contaminant Monitoring Rules to date. Several types of contaminants have been studied during the Unregulated Contaminant Monitoring Rules. EPA has reviewed microbiological contaminants such as microsporidia, helicobacter pylori and viruses, flame retardants, pesticides and pesticide metabolites, explosives, newly discovered disinfection byproducts, hormones, volatile organics, inorganics, metals and products of radioactive decay such as lead-210 and polonium-210. 4 THE DISCOVERY OF ENDOCRINE DISRUPTORS Prior to, and concurrent with, EPA’s Unregulated Contaminant Monitoring Rules, studies began to show that mixtures of chemicals were present in water sources in the parts per trillion (ng/L) range. As additional information became available on waterborne contaminants, it was noted that some of the chemicals were having an adverse effect on wildlife and people. Some of these newly discovered chemicals act like estrogen in human bodies and disrupt natural endocrine system functioning. In November of 2012, EPA published a list of contaminants called the Endocrine Disruptor Screening Program Universe of Chemicals. This list contains approximately 10,000 potential contaminants that come from a variety of different chemical classes. All of the contaminants on the list may not be harmful, but this list represents a starting point for further study. EPA has begun testing 67 of these contaminants for endocrine disrupting effects. Evaluation of contaminants in the Endocrine Disruptor Screening Program Universe of Chemicals will likely spur future drinking water regulations. THE FUTURE OF DRINKING WATER REGULATIONS The future of drinking water regulations will likely be influenced by additional advancements in detection of trace levels of the tens of thousands of possible contaminants that may be in natural waters. There are thousands of pharmaceuticals, metabolites of pharmaceuticals, pesticides and pesticide metabolites, disinfection byproducts, algal toxins, and other contaminants not yet included in EPA’s Endocrine Disruptor Screening Program Universe of Chemicals. While the Endocrine Disruptor Screening Program Universe of Chemicals is broad, there are notable absences. When pharmaceuticals are taken, they are excreted as many metabolites. Pesticides also break down into numerous metabolites through interaction with microbes, air, sunlight and water in the environment. The existing universe of chemicals is missing many of these contaminants. Furthermore, as technology advances, many new types of contaminants are created. An example of this is the emergence of nano technology. Nano participles will likely become a major water quality concern in the future. Nano particles represent a major threat to water supplies. The ability to dope a nano particle with chemicals is both a great advance in chemistry and a potential disaster for drinking water safety. Uncontrolled, or in the wrong hands, nano technology could result in widespread illness and unintended consequences for public health. Regulatory agencies have not yet formed a strategy to regulate these particles toward the goal of protecting human health. 5 HITTING THE “WATER QUALITY BULLSEYE” Observing the Safe Drinking Water Act (SDWA) regulations is similar to viewing a dart board, with the center of the dartboard representing the “Water Quality Bullseye”. Once the drinking water treatment industry is able to achieve a level of water quality that protects public health from a wide array of emerging contaminants and endocrine disrupting compounds, it will hit the “Water Quality Bullseye”. ENDOCRINE DISRUPTORS RULE? 1914 US Public Health Service Regulates Coliform Bacteria 1962 US Public Health Service Issues Standards for 28 Contaminants 2013 BLN Adds Missing Pharmaceuticals, Pharmaceutical Metabolites, Pesticide Metabolites, Fragrances, Algal Toxins and Disinfection Byproducts to EPA's List 1974 Safe Drinking Water Act 1976 National Primary Drinking Water Regulations 1979 Total Trihalomethanes Regulated 2013 & Beyond Rules In Progress Perchlorate, VOCs 1979 Secondary Standards 1986 Fluoride Standard Revised 2013 Total Coliform Rule, Revised 1987 - Phase I VOCs 2012 Unregulated Contaminant Monitoring Rule 3 (UCMR 3) 1989 Total Coliform Rule, Revised November, 2012 EPA Releases Endocrine Disruptor Screening Program Universe of Chemicals 1989 Surface Water Treatment Rule THE FUTURE 1991 Phase II VOCs, SOCs and IOCs 2010 Second List of Endocrine Disrupting Chemicals 1991 Lead and Copper Rule 1992 Phase V - VOCs, SOCs and IOCs 2009 Initial List of Endocrine Disrupting Chemicals 1995 - Nickel is Remanded 2007 Unregulated Contaminant Monitoring Rule 2 (UCMR 2) 1996 Amendments to Safe Drinking Water Act 2006 Stage 2 Disinfectant/ Disinfection Byproducts Rule 1996 The Information Collection Rule (ICR) 2006 Long Term 2 Enhanced Surface Water Treatment Rule 2006 Ground Water Rule 1998 Stage I Disinfectant/Disinfection Byproducts Rule 2002 Long Term 1 Enhanced Surface Water Treatment Rule 2001 Unregulated Contaminant Monitoring Rule 1 (UCMR 1) 1998 Interim Enhanced Surface Water Treatment Rule 2001 Filter Backwash Recycling Rule 2001 Arsenic Revised 2000 Radionuclides Rule As the bullseye shows, efforts to regulate drinking water quality have been undertaken since 1914, and the definition of “clean” water has gotten narrower as time has progressed. Development of new analytical technologies has allowed for detection of trace level contaminants at the parts per trillion (ng/L or ppt) level. As our understanding of pollution has progressed, the range of regulated contaminants has increased greatly. 6 KEY POINTS IN US DRINKING WATER HISTORY 1799 First municipal drinking water delivery system. 1890’s Sand filtration introduced. 1908 First use of chlorine for disinfection. 1914 1974 Safe Drinking Water Act (SDWA) enacted. 1993 Milwaukee Cryptosporidium outbreak. 1996-2006 Microbial/Disinfection Byproducts Cluster Regulations enacted. US Public Health Service Regulation for coliform bacteria. 1986 Additional contaminants regulated. 1996 Amendments to the SDWA Unregulated contaminant monitoring required. 2012 Endocrine Disruptor Screening Program Universe of Chemicals published by EPA. 7 CONCLUSION By reviewing the history of drinking water regulations, it is clear that the definition of clean water has evolved over time. Advances in analytical technology have shown that natural waters contain many contaminants. In response, EPA is now focused on emerging contaminants and potential endocrine disrupting compounds. It is expected that future drinking water regulations for these contaminants will continue to evolve. REFERENCES 1. 25 Years of the Safe Drinking Water Act: History and Trends. http:// permanent.access.gpo.gov/websites/epagov/www.epa.gov/saf water/consumer/trendrpt.pdf (Accessed 2/5/2014) 2. “The History of Drinking Water Treatment” US Environmental Protection Agency. EPA-816-F-00-006. February 2000. http:// www.epa.gov/safewater/consumer/pdf/hist.pdf (Accessed 2/5/2014) 3. “History of water filters”. http://en.wikipedia.org/wiki/History_of water_filters (Accessed 2/5/2014) 4. “1993 Milwaukee Cryptosporidiosis outbreak”. http://en.wikipe dia.org/wiki/1993_Milwaukee_Cryptosporidiosis_outbreak (Accessed 2/5/2014) 8 Beam, Longest and Neff 8126 Castleton Road | Indianapolis, IN 46250 | p: 317.849.5832 | f: 317.841.4280 | B-L-N.com