Discussion Regarding Community Focused Assessments

Introduction

Each day, communities are faced with contamination problems that pose, or are perceived to pose health threats to community members. While each contamination problem is unique, three brief scenarios are presented that illustrate the challenges involved in identifying the potential health risks as well as in choosing the most appropriate course of action to address those risks.

Scenario 1

A coastal community has been built around a vibrant fishery. Two marine fish species comprise the majority of the seasonal catch, and both species are sold commercially as well as consumed in significant quantities by community members. Anecdotal reports of contamination have prompted the local health department to hire a research laboratory to conduct sampling to determine whether toxicants occur in harvested fish. The laboratory results indicate that two contaminants occur in fish tissues, and their concentrations vary by species, fish size, and lipid (fat) content.

Some of the questions that might be important to this community include.

  1. What will the exposure be to people eating the fish? Are there specific age groups that get higher exposure? How different are exposures for people consuming different types of fish, different sizes of fish, or fish caught at different times of the year?
  2. What is the risk from exposure to the contaminant?
  3. What remediation options make a significant impact on the exposure to the community? If removing the fish from the diet is indicated, are there suitable alternatives for the fish?

Scenario 2

A large metropolitan area has recently been told that its municipal water source is located adjacent to a large, complex, abandoned hazardous waste site. The site received wastes composed of complex mixtures of solvents and electrical fluids including vinyl chloride and PCBs and metals including chromium, cadmium, and lead. There is concern that the hazardous wastes have migrated into the groundwater and are moving toward the city's drinking water source. While monitoring at the water treatment plant has not shown elevated levels of solvents or metals in source waters, there have been reports of elevated lead levels in drinking water drawn from individual residences using the municipal water.

Some of the questions that might be important to this community include.

  1. What contaminants exist in the municipal water and in what concentrations are they present?
  2. What is the exposure of the people served by this municipal water source? Does this exposure vary based on time of the year, or other demographic factor in the community?
  3. What is the toxicity of the contaminants? What is the risk from exposure to the contaminants in the water based upon how the community uses the water (drinking, bathing, swimming, irrigation, etc)?
  4. What options exist to reduce the risk to the community posed by the contaminated water? Is it feasible to clean up the water, find a new water source, or is there another option to reduce risk?

Scenario 3

Several new housing developments have sprung up along a major, north/south interstate highway in a three state area. Recently, new homeowners in each of the states have complained about odors coming from various areas within the new homes. There have also been complaints of headaches, nausea, and fatigue from homeowners, and some are beginning to claim that there is a link between the odors and the health complaints. Homeowners suspect that a new coating used on drywall to provide an additional seal and insulation is causing the odors and some have begun to pursue litigation to have the coated drywall removed and replaced. Unfortunately, the builder has gone bankrupt and has not left records of building product sources and content, including information about the sealant coating.

Some of the questions that might be important to this community include.

  1. What contaminants exist in the sealant coating? If contaminants exist, what will the exposure be to people?
  2. What is the toxicity of the contaminants? What is the risk from exposure to the contaminants? Could the health problems be linked to the contaminants, or is there another reason for the increase in health problems?
  3. What is the impact of reducing/removing the source of the contaminant?

These scenarios, and many like them, share two things in common:

  1. A presumption that the existence of a contaminant in the food, water, or environment (at any level) may cause serious health effects, and elimination of the contaminant (at any cost) is in the best interest of the community, and;
  2. An absence of an exposure and risk assessment demonstrating that exposure to the contaminants can or is resulting in adverse health effects among various subgroups of the community.

Each scenario also generates myriad questions, some of which we ask below, about the extent and magnitude of exposure and health risks and about decisions around how to manage those risks.

Q1: How can I assess the risks to the health of community members associated with exposure to contaminants that are identified in the environment?
Q2: How have exposure assessments been conducted historically?
Q3: Are there better approaches to assess exposure?
Q4: How can I get information on community-level dietary and activity patterns?
Q5: What can community-specific information on diet and activity tell me?
Q6: Is there software that can help me analyze this information?
Q7: Can I identify subpopulations (e.g., children, women, etc.) that are at greater risk than other members of the community?
Q8: Can LifeLine help me determine whether the public health measures that are in place or are proposed are adequate to reduce the risk to the community?
Q9: Can the LifeLine software help me establish priorities for cleanup or other actions to reduce risks?
Q10: What is the role of the community in the process of assessing and managing risk?