Drinking Water & Health Newsletter
March 1, 1994

Table of Contents

Chlorine, Containers and Cholera Prevention: A Life-Saving Strategy For Latin America
By Robert Quick, Fred Reiff and Linda Venczel

The Information Collection Rule: Challenges and Opportunities for Public Health Agencies
By Brian Kim Mortensen

Congress Begins Reauthorization of Nation's Two Major Water Quality Acts

Issues Surrounding the Regulation of Radon in Drinking Water
By Nancy E. Kinner

Note From The Chairman

A new strategy against cholera, a severe and sometimes fatal diarrheal illness that has plagued Latin America since 1991, has shown promise in recent field trials and may soon be employed on a large scale.

The Centers for Disease Control and Prevention (CDC), The Pan American Health Organization (PAHO) and the University of North Carolina are currently collaborating with Bolivian health agencies in testing the efficacy of this strategy in several communities in Bolivia.

Testing a New Water Disinfection Strategy

The approach is targeted to populations most vulnerable to cholera and other waterborne diseases, namely people who reside in areas that lack safe piped water supplies and adequate treatment systems. The strategy enables communities to produce and distribute to households an effective water disinfectant, and equips and motivates those households to disinfect their own water.

Water Storage Containers

Central to this approach is providing the households with storage containers in which to disinfect and store water to preclude its recontamination. Specifically, narrow-mouthed, lidded, 20-liter plastic water containers with a spigot are recommended. (See diagram A.)

Chlorine Generators

A variety of versatile, low-cost chlorine generators are available which have great potential for local or community use in developing countries. The generators are basic electrolysis cells which convert a solution of common salt and water into a disinfectant solution, either sodium hypochlorite or a mixture of chlorine and other oxidants, depending upon the specific design. These devices are simple and inexpensive to operate and maintain, and are quite durable. A single device can provide enough disinfectant to serve several thousand families at an estimated monthly cost of less than 15 cents per family.

Both the effectiveness and practicality of household-level water disinfection have already been demonstrated in two Bolivian communities.

Two Success Stories

In an impoverished neighborhood in the city of El Alto, Bolivia, families using specially designed household water containers and locally produced sodium hypochlorite solution were able to eliminate all traces of water contamination with fecal coliform bacteria and Escherichia coli. Similarly, a group of Aymara Indian families in the rural village of Huaricana have produced safe drinking water from fecally polluted sources through disinfection with chlorine generated in the village.

Future Efforts

The next step will he to demonstrate the ability of this simple water treatment and storage system to decrease the incidence of cholera and other diarrheal diseases in a Bolivian community. The CDC, PAHO and University of North Carolina are planning to conduct this study in Bolivia in 1994 and possibly 1995. Rapid deployment of this system, which will include production of the water containers and chlorine generators in Bolivia could follow soon after.

Millions of Latin American families that lack access to safe water supplies would benefit from a reliable, cost-effective means to protect themselves from cholera and the many other waterborne diseases which afflict them. There are more than fifteen serious and often deadly diseases, which are transmitted to a considerable extent by contaminated drinking water, that could be controlled by adequate disinfection. The Pan American Health Organization hopes to carry out similar projects in three to eight other countries in the near future.

Robert Quick is a medical epidemiologist with the Foodborne and Diarrheal Diseases Branch of the U.S. Centers for Disease Control and Prevention. Linda Venczel is a Ph. D. candidate in environmental sciences at the University of North Carolina at Chapel Hill.

THE INFORMATION COLLECTION RULE: CHALLENGES AND OPPORTUNITIES FOR PUBLIC HEALTH AGENCIES

In the near future, a new federal drinking water rule will go into effect requiring increased monitoring for waterborne pathogens and chemicals. The new mandate, known as the Information Collection Rule (ICR), will require the involvement and understanding of public health professionals.

Under the ICR, public health officials may be asked to interpret health risks associated with the occurrence of drinking water contaminants. In some cases these health risks may require greater involvement of public health professionals. in detecting and controlling communicable disease outbreaks.

It is vital that public health officials understand the process and limitations of how this data is gathered and assessed, and are prepared to communicate information about the risk of waterborne disease to the public.

The ICR is part of the U.S. Environmental Protection Agency's (EPA's) two-phase regulatory negotiation process to develop rules to control risk from disinfectants and disinfection by-products (D/DBP) in drinking water. The D/DBP rule is intended to reduce potential health risks from D/DBPs without increasing the risk of infectious disease.

The ICR was mandated due to a lack of critical data about the effects of new water treatment and disinfection methods on water chemistry and the removal or destruction of pathogens and chemicals.

The ICR will require larger water treatment facilities to collect data on the occurrence of indicator bacteria, protozoan and viral pathogens, and concentrations of chemicals in drinking water. One of the ways this data will be used is to assess risks of cancer and birth defects from exposure to chemicals in drinking water and to compare them with infectious disease risk from waterborne pathogens.

Risk Assessments - Limitations and Uncertainties

The EPA will conduct risk assessments using the data collected under the ICR. The results of these assessments will be used in making risk management decisions and helping to explain to the public the nature, magnitude and uncertainty about the risk estimate. The EPA will use its standard risk assessment procedure - defined as a "process to characterize potential adverse effects to humans (or the environment) resulting from exposure to environmental hazards."

This approach presents several challenges: scientists have developed methods to quantify cancer and non-cancer risks from exposure to chemicals; however, EPA lacks similar methods to estimate the probability of disease and harm when assessing concentrations of pathogens in water.

There also is no easy or accepted way to compare chemical risk with infectious disease risk. It is not clear that the assessment of the health risks from the two competing risks will be conducted on equal footing. This disparity may result in an unintentional emphasis on chemical risk while minimizing the risk from pathogens. A biased emphasis could result in a large effort to reduce a small chemical risk while ignoring, or perhaps even increasing, a larger risk of communicable disease.

Additionally, these chemical risk assessments often have not been accompanied by important information that might improve public knowledge and acceptance of their conclusions. Most significantly, they often have not conveyed how much cost is associated with different levels of risk reduction, and what trade-offs from competing risk we may incur in pursuing a new means to reduce the risk being considered.

Opportunities for Public Health Agencies

The ICR presents a threefold opportunity for health agencies to apply their expertise in disease surveillance, risk assessment and risk communication. Health departments need to be prepared to discuss the meaning of the ICR data on pathogens and chemical contaminants. This includes explaining infectious disease risk and answering questions about changes in waterborne disease rates when new drinking water disinfection methods mandated by the regulations are implemented.

Public health agencies can and should use their considerable experience in assessing and explaining risks, and take an active part in the assessment process to complement the roles of environmental agencies and drinking water providers.

Note: The opinions expressed in this article do not necessarily reflect the official position of the Ohio Dept. of Health.

CONGRESS BEGINS REAUTHORIZATION OF NATION'S TWO MAJOR WATER QUALITY ACTS

Reauthorization efforts are currently under way for the nation's two major water quality acts the Safe Drinking Water Act (SDWA) and the Clean Water Act (CWA). Revisions under consideration will likely have a major impact on water treatment facilities and other aspects of public health protection.

The Clean Water ACT

June will likely see significant action in the House and Senate on several reauthorization bills. In the Senate, S. 2093 awaits floor action. In the House, the Public Works and Transportation Committee will consider H.R. 3948 and a competing alternative.

While debates around some of the provisions within these bills remain to be settled, key themes have emerged:

• Water Quality Control
  Proposals call for increased control of discharges from municipal sources such as overflows from combined storm and sanitary sewers and control of municipal stormwater. Proposals also encourage water management on a watershed basis and expanded efforts to control non-point sources of pollution.

• Standard Setting/Risk Assessment
  Efforts to improve the use of risk assessments and sound science in Setting water quality standards - in both the Clean Water Act and the Safe Drinking Water Act are critical to reauthorization efforts.

• Water Pollution and Control
  Reauthorization proposals call for additional programs to prevent and control water pollution. These programs include prevention planning, phase-out of specific toxic discharges, and expanded regulation of industrial dischargers and non-point sources.

• Enforcement and Compliance
  Proposals include provisions intended to improve compliance with the Clean Water Act, including expanding citizen suit authority and providing authority for enforcement against federal facilities.

Another, but less publicized, element of the Clinton Administration's Clean Water Act recommendations - and one that could have a significant impact on public health practitioners if implemented - was the proposal to "develop a national strategy for substituting, reducing or prohibiting the use of chlorine compounds." This language has not been incorporated into any House or Senate bills, but could surface as an amendment during debate on the House or Senate floor.

The Safe Drinking Water Act

With public concern about the safety of tap water, legislative anger about unfunded mandates and Administration concerns about non-compliance, efforts to reauthorize the Safe Drinking Water Act (SDWA) have resulted in an intense political battle. The most contentious issue in this debate centers around the process by which the EPA establishes drinking water standards.

The Administration Proposal
In late 1993, the EPA introduced the Administration's SDWA reauthorization proposal.

Major items addressed in the EPA's SDWA proposal include:

• Source water protection

• Small system viability

• Enforcement and compliance

• Standard setting

While initial legislative activity focused on the establishment of a State Revolving Fund, the debate soon turned to unfunded mandates and the standard-setting process. State and local officials have long argued that federal drinking water regulations place an undue burden on their budgets without showing commensurate benefits.

The Slattery/Bliley Bill
Responding to these concerns, Reps. Jim Slattery (D-Kan.) and Thomas Bliley (R-Va.) introduced a reauthorization bill, H.R. 3392. The bill has the support of the Safe Drinking Water Act Coalition (SDWAC), an alliance of 12 state and local organizations (e.g., National Governors' Association) and drinking water groups.

Under this legislation, regulators would not be allowed to impose new standards until they demonstrate that the benefits of such standards outweigh the cost of compliance. The SDWAC, and many lawmakers, believe this approach will strengthen public health protection by applying available resources to control the most significant public health risks. However, the cost-benefit approach has been criticized by some environmental groups and Members of Congress who allege that it will weaken public health protection.

The Slattery/Bliley bill also faces a significant challenge from the House Health and Environment Subcommittee. The subcommittee's chair, Henry Waxman, opposes H.R. 3392 and has threatened a legislative stalemate over the standard-setting issue.

The Baucus Bill
In early Spring 1994, the Baucus bill (S. 1547) won the support of the Senate Environment and Public Works Committee, which Max Baucus (D-Mont.) chairs. Characterized as a "balanced solution" to the SDWA debate, the bill was designed to help build a consensus among the differing parties.

On May 19, 1994, the Senate passed the Baucus bill (S. 2019, formerly S. 1547) to reauthorize the SDWA. This bill requires greater use of risk/ benefit analysis and attention to sensitive populations in setting standards, and emphasizes the use of sound science as the foundation for regulations. The House has yet to adopt a reauthorization bill.

Current Safe Drinking Water Act Regulation
Stemming from the EPA's Regulatory Negotiations Committee (Reg-Neg), the Information Collection Rule will go into effect in late October or November this year. Designed to build a broad database of contaminant occurrence data to facilitate future rulemaking, the ICR requires increased monitoring at all water treatment facilities serving more than 10,000 people.

The EPA is drafting proposed language for the Disinfectant/Disinfection By-Products (D/DBP) and Enhanced Surface Water Treatment Rules (ESWTR), based on the outcomes of the Reg-Neg process. While currently trying to resolve issues around language in the D/DBP rule's preamble, the EPA anticipates that the draft rules will be published for public comment in June 1994.

For additional information on the reauthorization process, or on current SDWA legislation, contact your Member of Congress or the U.S. EPA Safe Drinking Water Hotline at 800-426-4791.

ISSUES SURROUNDING THE REGULATION
OF RADON IN DRINKING WATER

Radon is one of the six radionuclides for which the U.S. Environmental Protection Agency (EPA) proposed National Primary Drinking Water Regulations in July 1991. Currently, the fate of the radon standard is unclear. It is certain, however, that radon will ultimately be regulated, most probably with the maximum contaminant level (MCL) in the range 300-2,000 picocuries per liter (pCi/L), because it is a known carcinogen. [N.B., See "Congress to Decide Fate of Radon Standard" by F.W. Pontius and D.B. Paris in JAWWA Jan. 1994 for a detailed discussion of history of the radon regulation.]

Impact on Water Utilities

There is general agreement that the radon regulation, if it is promulgated at 300 pCi/L, will affect a wide spectrum of water utilities. The greatest impact will be on small communities and point-of-energy systems that use a proportionately greater percentage of groundwater. Estimates vary greatly, but most agree that constructing and operating treatment systems that meet an MCL of 300 pCi/L could cost billions of dollars. Congress will consider the complete issue surrounding the radon standard as it debates the reauthorization of the Safe Drinking Water Act. The resulting legislation could set important precedents not only affecting the radon MCL, but the entire regulatory process for drinking water contaminants.

Standard-Setting Controversy

While the regulatory process for drinking water contaminants is often protracted, the controversy surrounding the radon standard results from its unique characteristics. Most importantly, radon is a naturally occurring radionuclide, the direct progeny of radium and part of the uranium decay series. Because uranium is present in many geological formations (e.g., granite), radon can be found in groundwater associated with uranium-bearing bedrock. Unlike many regulated contaminants, the presence of radon in water is not the result of human activities.

Of the six radionuclides to be regulated in drinking water, radon is the only gas. It can enter buildings and homes via groundwater used as a water source or as soil gas entering through the foundation. Radon is highly volatile and moves readily from water into air, especially when water is agitated (e.g., during showering or laundering). Currently, the EPA-recommended guideline for radon in air is less than 4 pCi/L. Using the standard assumption that 10,000 pCi/L of radon in water will result in 1 pCi/L in air, the recommended air guideline would only be exceeded if the radon concentration in water exceeded 40,000 pCi/L (where water was the sole source of radon).

The vast majority of groundwater in the U.S. contains less than 2,000 pCi/L (average concentration is 650 pCi/L), while the average air level is 1 pCi/L This suggests that soil gas is probably an important source of indoor air contamination in many cases. As EPA's Science Advisory Board (SAB) has noted, regulation of radon should involve a multimedia approach to risk reduction. It is important to discriminate whether source reduction efforts should be focused on remediation of soil gas and/or groundwater.

Radon Risk Assessment

The risk assessment data used to establish the proposed MCL for radon in drinking water includes studies involving inhalation and ingestion. While few dispute the carcinogenicity of radon and its progeny, there is considerable disagreement regarding the assumptions and interpretations of the risk assessment studies. For example, in one ingestion study, diffusion of radon across the stomach wall was modelled by xenon, but the similarities between diffusion of radon and xenon have been questioned. Others question whether the risk at low levels should be linearly extrapolated to zero or whether a naturally occurring threshold concentration should be used. These issues and several others have led the Science Advisory Board (SAB) to criticize many of the risk-based assumptions underlying EPA's proposed MCL.

Besides risk, the two other considerations in establishing an MCL are availability of treatment technology (Best Available Technology, BAT) and analytical detection capabilities. However, for radon neither of these considerations presents a major issue in setting the MCL. BAT for radon exploits its high volatility and removals of 99% or more are achievable with packed tower, tray and diffused bubble aeration system. Monitoring radon concentrations in water using liquid scintillation analysis is relatively easy even for levels below the proposed MCL of 300 pCi/L, though counting times may be long (i.e., 50-100 min./sample).

Note From The Chairman

Protecting Groundwater Resources - A Critical Step In Ensuring Safe Drinking Water

More than 50% of the American population's drinking water comes directly from sources beneath the surface of the earth, or "groundwater." Groundwater is used by 95% of the people living in rural communities and makes up 95% of all the available freshwater resources in the United States.

As such, maintaining the safety of groundwater resources is of paramount importance to the nation's drinking water providers and public health officials. With the quality of America's drinking water in the spotlight, and both the Clean Water Act (CWA) and the Safe Drinking Water Act (SDWA) up for reauthorization, much attention and debate has been generated around how groundwater is managed and protected.

To ensure that our readers are well-informed on the implications of these debates, the next issue of "Drinking Water & Health" will focus primarily on groundwater safety and protection. Topics to be addressed will include:

• Source Water Protection (SWP). A key component of the EPA's SDWA reauthorization proposal for both surface and groundwater, SWP programs will offer incentives for states and communities to institute measures to prevent contamination of drinking water supplies.

• Groundwater contamination. What are the emerging chemical and microbial contaminant issues? How will monitoring requirements change to meet new standards?

• Groundwater treatment. Are treatment procedures likely to change as a result of the reauthorization process?

Please let us know if you have any suggestions for other groundwater related topics you would like to see addressed in this newsletter. A form is included with this newsletter for submitting your ideas.

Drinking Water & Health Newsletter is a Publication of the Public Health Advisory Board to the Chlorine Chemistry Council

THE PUBLIC HEALTH ADVISORY BOARD

SANFORD M. BROWN, JR.,
PH. D. School of Health and Social
Work, California State
University, Fresno

BRUCE K. BERNARD, PH D.
SRA International
Washington. D. C.

LINDA GOLODNER
National Consumers League
Washington, D. C.

RALPH MORRIS, M.D.
Galveston County (Texas)
Health District

FRED REIFF
Pan American Health Organization
Washington, D.C.

JOAN ROSE, PH. D.
College of Public Health
University of South Florida
Tampa, Florida

Chlorine Chemistry Division of the American Chemistry Council