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This article reviews the American Water Works Association Statement of Policy on Drinking Water Quality and the US Environmental Protection Agency standard for total dissolved solids (TDS) in drinking water. Data from the California Mineral Taste Study (CMTS), which established a functional relationship between TDS and taste quality assessed by consumers and taste‐panel members, are summarized. The CMTS data indicate that for mineral content a TDS of 450 mg/L will result in a good quality water and that a TDS of 80 mg/L will result in an excellent quality water. A cost comparison between systemwide demineralization and the purchase of bottled water by individual consumers shows that systemwide demineralization may be less costly to the residential consumer. Such information, when developed for a particular utility, can be presented to the community and used to make an informed decision regarding systemwide water treatment for reducing TDS to levels consistent with good or excellent water quality.

Recent terrorist events underscore the urgent need to develop a comprehensive set of health-protective cleanup standards and effective decontamination technologies for use in the restoration of civilian facilities. Accurate scientific information remains limited in the area of biological warfare agents. However, new guidelines and calculated cleanup values are emerging for initial re-entry and long-term reoccupation following use of chemical warfare agents. This article addresses airborne, soil, and surface exposures following release of G-type chemical warfare agents and VX. Cleanup goals should be tailored to the type of population that may be exposed, potential exposure times, and other scenario-specific considerations. Three different airborne concentrations are proposed for cleanup of public sector facilities. One value is recommended for initial re-entry; a more conservative value is recommended for long-term monitoring and increased public confidence; and a third, even more conservative concentration represents essentially a no-effect level for round-the-clock airborne exposure. Health-based cleanup levels are provided for contaminated residential and industrial soil. Results are presented on the outcome of a preliminary risk assessment to determine safe surface levels (e.g., walls, floors, and handrails) for cleanup after exposure to the G agents and VX. Because specific cleanup criteria for most biological warfare agents remain problematic, recommendations are made for filling the knowledge gaps.

Industrial societies have altered the earth's environment in ways that could have important, longterm ecological, economic, and health implications. In this paper, we examine the extent to which uncertainty about global climate change could impact the precision of predictions of secondary outcomes such as health impacts of pollution. Using a model that links global climate change with predictions of chemical exposure and human health risk in the Western region of the United States of America (U.S.), we define parameter variabilities and uncertainties and we characterize the resulting outcome variance. As a case study, we consider the public health consequences from releases of hexachlorobenzene (HCB), a ubiquitous multimedia pollutant. By constructing a matrix that links global environmental change both directly and indirectly to potential human-health effects attributable to HCB released into air, soil, and water, we define critical parameter variances in the health risk estimation process. We employ a combined uncertaintyhensitivity analysis to investigate how HCB releases are affected by increasing atmospheric temperature and the accompanying climate alterations that are anticipated. We examine how such uncertainty impacts both the expected magnitude and calculational precision of potential human exposures and health effects. This assessment reveals that uncertain temperature increases of up to 5°C have little impact on either the magnitude or precision of the public-health consequences estimated under existing climate variations for HCB released into air and water in the Western region of the U.S.

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Industrial societies have altered the earth's environment in ways that could have important, longterm ecological, economic, and health implications. In this paper, we examine the extent to which uncertainty about global climate change could impact the precision of predictions of secondary outcomes such as health impacts of pollution. Using a model that links global climate change with predictions of chemical exposure and human health risk in the Western region of the United States of America (U.S.), we define parameter variabilities and uncertainties and we characterize the resulting outcome variance. As a case study, we consider the public health consequences from releases of hexachlorobenzene (HCB), a ubiquitous multimedia pollutant. By constructing a matrix that links global environmental change both directly and indirectly to potential human-health effects attributable to HCB released into air, soil, and water, we define critical parameter variances in the health risk estimation process. We employ a combined uncertainty/sensitivity analysis to investigate how HCB releases are affected by increasing atmospheric temperature and the accompanying climate alterations that are anticipated. We examine how such uncertainty impacts both the expected magnitude and calculational precision of potential human exposures and health effects. This assessment reveals that uncertain temperature increases of up to 5 degrees C have little impact on either the magnitude or precision of the public-health consequences estimated under existing climate variations for HCB released into air and water in the Western region of the U.S.