Measuring up: examining the need to establish state-based biomonitoring programs.

Introduction

Breast milk contaminated with flame retardants, blood containing pesticides banned long ago, and arsenic-tainted drinking water: These scenarios and dozens like them are referred to regularly on local and national news programs and in newspapers across the nation. They illustrate the pressing need for vigilant monitoring of environmental chemicals and toxicants and associated human exposures. How should the United States begin to address human exposures to environmental chemicals and, more critically interpret what those exposures mean in terms of human health? A means of addressing these crucial environmental health quandaries is the laboratory-based tool known as human biomonitoring.

What Is Biomonitoring?

Biomonitoring is the process by which chemicals, their metabolites, or both are measured in human clinical samples like blood, urine, saliva, breast milk, and tissues such as hair. Decades ago, elevated levels of lead in blood were found to cause severe cognitive deficits, including mental retardation. As a result, programs and policies were developed to prevent exposure to lead in the environment; an example is the phased removal of lead from gasoline products in the United States in the 1970s. The nation's public health laboratory system and the National Center for Environmental Health (NCEH) of the Centers for Disease Control and Prevention (CDC) have played an essential role in human biomonitoring for many years. CDC has provided laboratory support in many instances, including for both national and international incidents that presented a need for population exposure monitoring.

To date, the primary focus in biomonitoring at the state level has been on the prevention of childhood lead poisoning. The time has come to expand beyond lead protection programs and to begin monitoring for new and emerging exposure hazards and to identify "hot spots" where public health and public safety may be at risk. Data obtained through biomonitoring are used at all levels of government in the development of public policy and the evaluation of results from policy changes. State biomonitoring programs serve the important purpose of developing and enhancing the capability of each state public health laboratory to determine the actual dose of environmental toxicants of concern to which residents are exposed and, more important, to determine what the dose signifies in terms of health risk.

Federal Support for Biomonitoring

Over the past three years, the Association of Public Health Laboratories (APHL) has worked closely with the NCEH Division of Laboratory Sciences to launch the State Public Health Laboratory Biomonitoring Planning and Implementation Grant Program. The purpose is to build biomonitoring capacity for state public health laboratories across the nation. This program distributed $5 million to 25 applicants (covering 33 states), several of which represented multistate consortia. In January 2003, APHL, in partnership with CDC, held the 50-State Biomonitoring Meeting. The meeting was an opportunity for state and national biomonitoring programs to discuss their biomonitoring-related activities.

Although the CDC grants afforded most states the funding needed for planning of their biomonitoring programs, additional resources are crucial if those states are to succeed in implementing and sustaining the plans. Finding money for states without biomonitoring programs is even more critical. From 2003 to 2005, just three grantees received funds to begin implementing biomonitoring plans: New York, New Hampshire, and The Rocky Mountain Biomonitoring Consortium, which comprised state public health laboratories in Arizona, Colorado, Montana, New Mexico, Utah, and Wyoming. The amount of federal funding being made available to these states continues to significantly decline with each new fiscal year; altogether, those three grantees received less than $3 million.

The Role of State Public Health Laboratories in Biomonitoring

State health departments are regularly called upon to investigate clusters of cancer or birth defects in order to determine whether the occurrence of these health conditions is the result of exposure to environmental chemicals and contaminants. In addition, state health officials are often involved in investigating the accidental or deliberate release of hazardous materials, which may carry the potential for hazardous exposures. In these situations, biomonitoring is a tool that state health officials can use to address public concerns following exposures to environmental contaminants.

State public health laboratories provide the stage upon which biomonitoring is performed. If a laboratory is to conduct biomonitoring, it needs highly specialized, state-of-the-art laboratory instrumentation. To perform the detailed analyses required to obtain quality exposure data, a technically skilled workforce is needed as well. State public health laboratories, if adequately funded, are well placed to provide the staff and equipment. Thus, they can play a fundamental role in public health efforts aimed at gathering the focused and tangible human-toxicity data needed to link chemical exposures to subsequent health effects, functioning as a component of a larger public health infrastructure. In some cases, the laboratory itself may be conducting clinical sampling within a particular community or state and may thus be independently gathering data to support its own biomonitoring studies. In other cases, state laboratories may be working in collaboration with other state or national programs, such as tracking and surveillance networks, to conduct human biomonitoring studies that provide human clinical data (from blood, urine, saliva, etc.) on exposure levels, the presence of environmental chemicals in the body, and so forth. These data can then complement environmental data and epidemiological data being collected by the state health department and other state agencies. The data sets can be married to each other to establish linkages and relationships between humans, environmental exposures, and disease outcomes.

Relationships Between Biomonitoring and Other Public Health Programs and Activities

The status of state public health laboratory biomonitoring programs strongly affects the way a state responds to chemical-terrorism events and other chemical-exposure incidents of public health significance. The laboratory instrumentation, supplies, and personnel can be utilized to monitor individuals that have been, or may have been, exposed to a chemical or multiple chemicals during an incident. Thus, providing biomonitoring funds to the states also helps build the infrastructure needed to protect the public from domestic or international terrorism, a concept known in the public health laboratory community as "full use."

With the recent announcement of CDC's 2005 Bioterrorism Preparedness Cooperative Agreement, state laboratories stand to boost their level of preparedness for chemical terrorism and to enhance biomonitoring capacity. States will be able to use cooperative-agreement monies to acquire new instruments and to become proficient in new methods of analyzing clinical samples to determine the presence of chemical agents such as heavy metals, mustard agents, nerve agents, and cyanide, to name a few. Laboratories involved in biomonitoring use similar techniques and testing methods. As a result, as states broaden their testing capability for chemical-terrorism agents, they simultaneously build biomonitoring capability, allowing them to make full use of their training and instrumentation by applying skills in two separate areas of laboratory science.

Yet another strong relationship exists between state public health laboratory biomonitoring programs and the NCEH-funded National Environmental Public Health Tracking Network (EPHTN). The purpose of this network is to build state and national databases that are capable of integrating environmental-contamination, human-exposure, and human-health-effects data and to facilitate data sharing among public health officials at the federal, state, and local levels. The data can then be used for effective environmental health surveillance and for the development of policies and plans that address exposure to environmental chemicals and health effects issues. In the public health and clinical community tracking data are regarded as being highly effective in promoting environmental health surveillance. Often overlooked, however, is the fact that tracking data can best be used in this manner when they are supported by the appropriate biomonitoring data.

Biomonitoring data provide a unique laboratory-based tool for attaining reliable, hypothesis-driven research. In turn, such research is necessary for obtaining the quality data required to both enhance understanding and increase ability among public health and medical professionals so that they can begin to accurately identify relationships between environmental exposures and disease. Biomonitoring studies complement environmental data and provide evidence that environmental contaminants are present (or not) in the human body. In this way, biomonitoring provides the public health community with scientific data which, when coupled with environmental data, serve as a reliable rationale for the formulation of sound environmental health policy decisions.

The Bottom Line

Currently, scant data on the body burden and health effects associated with chemical exposures in the daily environment are available to public health professionals, scientists, and researchers. This lack of human-biomonitoring data is problematic for several reasons. First, uncertainty about the amount of a substance actually present within the human body makes it virtually impossible to detect, monitor, and link environmental exposures with subsequent health effects. Similarly, for certain environmental chemicals, the absence of toxic-level human-exposure data translates into a very limited understanding of the clinical toxicity of substances once they enter the human body. Sufficiently supported, state public health laboratory biomonitoring programs can provide the fundamental data needed to implement and maintain effective public health programs.

Integrating state public health laboratory biomonitoring capacity and capability with other public health programs and activities fosters vital connections among public health, environmental health and science, and medical professionals. Biomonitoring programs also lead to increased communication and partnership opportunities among public health laboratory staff; public health epidemiologists; toxicologists; environmental health/environmental science professionals; members of the clinical community; and, perhaps most important, members of the public, who have a right to know about the impact that exposures to environmental chemicals may have on their health.

For additional information on human biomonitoring, readers are invited to visit the APHL Web site at http://aphl.org/programs/environmental_health/biomonitoring.cfm.

Corresponding Author: Lauren DiSano, Environmental Health Program Manager, Association of Public Health Laboratories (APHL), 8515 Georgia Avenue, Suite 700, Silver Spring, MD 20910. E-mail: [e-mail].

Resources

Association of Public Health Laboratories. (n.d.). Biomonitoring. Retrieved October 24, 2005, from http://aphl.org/programs/environmental_health/biomonitoring.cfm.

Association of Public Health Laboratories. (2004, May). Biomonitoring: Measuring chemicals in people. Washington, DC. Author.

Centers for Disease Control and Prevention. (n.d.). Biomonitoring and EPHT. Retrieved October 24, 2005, from http://www.cdc.gov/nceh/tracking/biomonitoring.htm.

Centers for Disease Control and Prevention. (2005, December). National biomonitoring program. Retrieved October 24, 2005, from http://www.cdc.gov/biomonitoring/.

Lauren DiSano, M.H.S.