The Human Biomonitoring for Environmental Chemicals Report was sponsored by the U.S. Environmental Protection Agency (EPA) and the Centers for Disease Control and Prevention (CDC) in response to a Congressional directive. The report recommends numerous ways to improve the collection, analysis, uses, and interpretation of biomonitoring data, as well as to communicate these data to the public. Copies of the report are available for purchase at www.nationalacademies.org. Following are the highlights of this important report and several key implications.
Biomonitoring gains attention
Biomonitoring is the measurement of chemicals in blood, urine, and other human bodily fluids and tissue. Looking for chemicals in the body isnt new and finding them isnt unexpected. Occupational safety and health regulatory agencies have, for example, used biomonitoring data for decades. What is relatively new is the publics broader appreciation that chemicals are found in our bodies and it isnt always clear what this fact means.
Interest in biomonitoring has increased dramatically since 2001 when CDC issued its first National Report on Human Exposures to Environmental Chemicals. Although these three bi-annual national reports indicate that representative samples of the population have low levels of chemicals in their bodies, interpreting the meaning of the levels from a public health risk perspective is challenging, given the lack of data and the absence of a known risk framework to assess the utility and meaning of these data.
The following discussion highlights a number of the recommendations in the report.
Characterizing and interpreting biomarkers
The committee proposed a framework for grouping biomarkers, which are a distinctive biological or biologically derived indicators of a process, event, or condition. They are grouped by exposure to help the users of biomarkers to understand the advantages and the limits of interpretation of biomarker results. This systematic framework to characterize the properties of biomarkers informs scientists and the population at large about biomarkers and their use in biomonitoring studies. The committee recommended that investigators use the proposed framework.
The report identifies two options for interpreting the results of a biomonitoring study descriptive and risk-based approaches. A descriptive approach typically establishes a reference range (e.g., 50th percentile) to compare an individuals results. The risk-based approach is more data intensive. Only a relatively small number of chemicals currently sampled by CDC permit a risk-based approach. Biomonitoring data also can inform risk assessment and risk management by demonstrating how effectively intervention measures have decreased exposures to a particular chemical, the report states.
The report also emphasizes the strong need for effective communication between researchers and nonscientists, and includes useful information on the principles of risk communication as well as practical recommendations for biomonitoring communicators. When biomonitoring results are below the limit of detection, the report underscores that this is not an indicator of nonexposure, and this needs to be conveyed clearly to lay constituents of biomonitoring. Numerous research recommendations also are provided, the most fundamental is the need to determine the best ways to communicate biomonitoring results in the absence of science to interpret the data.
Despite the uncertainties about their human health relevance, biomonitoring data will continue to influence global, national, and state regulatory and legislative developments for years to come. Chemical Processing readers should stay abreast of these issues, become knowledgeable about the human-health and environmental effects of chemicals relevant to your chemical manufacturing and processing operations, and be prepared to respond to questions from employees, neighbors, downstream purchasers, and users about the presence of chemicals in human fluids.
Lynn Bergeson is the managing director of Bergeson & Campbell, P.C., a Washington, D.C.-based law firm that concentrates on chemical industry issues. Contact here at firstname.lastname@example.org. The views expressed herein are solely those of the author. This column is not intended to provide, nor should be construed as, legal advice.