Special Issue of Journal Explores Connection Between The Health of the Chesapeake Bay and The Health of People

The February 2000 issue of Environmental Research gathers together scientific papers generated by a 1998 colloquium, "Health of the Bay--Health of People," which explored the connections between public health and the environmental quality of the Chesapeake Bay. These papers on the difficulties and limitations of current efforts to monitor and assess the Bay's health led to the consensus of the conference that "clearly, our actions and policies can no longer ignore the connection between human health and the environment." Human health indicators, the conferees agreed, must be included in any assessment of the environmental health of the Bay, and monitoring must be more effectively integrated across agencies and over time.

The colloquium, which was held at the Johns Hopkins School of Public Health in November 1998, was sponsored by the School's Center for a Livable Future and by the Chesapeake Bay Foundation (CBF).

Balancing the positive impacts of economic development around the Bay region with the attendant adverse effects on the environment is a continual challenge for policy makers. As early as 1607, half the early settlers at Jamestown are thought to have perished from drinking water contaminated by their own wastes. Today, the National Oceanic and Atmospheric Administration estimates that one fifth of the water entering the Chesapeake Bay at any one time is wastewater from industry and sewage treatment. Summaries of the six papers published:

"Health of the Bay -- Health of People." Authors: William C. Baker, president, Chesapeake Bay Foundation, and John D. Groopman, PhD, professor and chair, Environmental Health Sciences, Johns Hopkins School of Public Health. Short-term cost-cutting strategies, which frequently benefit only a narrow slice of the community, account for much of society's impact on the environment. The true costs of these shortcuts are disguised, and thus often only show up over the long term in the bills for health care and environmental clean-up. As the authors state, "One cannot avoid the future costs of one's actions, only transfer them to others."

The report details a possible model, developed by the Chesapeake Bay Foundation (CBF), for assessing the environmental health of the Bay. In the CBF system, the pristine Chesapeake, as described by explorers during the early 1600s, is assigned a perfect score of 100. Each year, the CBF now compares the status of eleven indicators -- including crab and rockfish numbers, water clarity, and the health of sea grasses -- with this perfect score of 100. Out of a possible 100, today's Bay earns a score of 27.

"Measuring the Health of the Bay: Toward Integration and Prediction." Author: Donald F. Boesch, professor, University of Maryland; president, Center for Environmental and Estuarine Studies. This report provides an overview of the Chesapeake Bay Program, which for nearly 14 years has employed over 165 monitoring stations in the tidal waters of the Bay and its tributaries to gather routine measurements of, among other things, nutrients, suspended sediments, toxins in water and sediments, water temperature and salinity, dissolved oxygen, vegetation, plankton, and fish. The report also discusses why these good, specific monitoring programs fail to protect the Bay.

"Linking Public Health and the Health of the Chesapeake Bay." Lead author, Thomas A. Burke, PhD, MPH, associate professor, Health Policy and Management, Johns Hopkins School of Public Health. Although the Chesapeake Bay is one of the most studied ecosystems in the world, fundamental gaps remain in our knowledge of the public health implications of Bay pollution. This report describes the balkanized nature of our regulatory, conservation, and public health efforts, which has made it difficult to develop a cohesive picture of the overall status of the watershed. The paper then presents a framework for coordinating public health efforts so as to demonstrate the connections between public health and the Bay.

"Susceptibility of the Chesapeake Bay to Environmental Contamination with Cryptosporidium parvum." Lead author: Thaddeus K. Graczyk, PhD, MSc, associate scientist, Molecular Microbiology and Immunology, Johns Hopkins School of Public Health. This paper describes Dr. Graczyk's work with the Maryland Sea Grant Project, which is trying to determine whether oysters containing infectious Cryptosporidium parvum oocysts (a form of the microorganism) pose human health risks, and then identify the environmental factors associated with contamination of the oysters in the Bay. The study, for example, has shown that aquatic birds such as Canada geese ingest C. parvum when they glean food from cow pastures, and then broadcast the pathogen to Bay waters by means of their feces.

"Pfiesteria: Harmful Algal Blooms as Indicators of Human-ecosystem Interactions." Lead author: Ellen K. Silbergeld, PhD, director, University of Maryland Program in Human Health and the Environment; adjunct professor, Health Policy and Environmental Health Sciences, Johns Hopkins School of Public Health. Because the rise and fall of algal populations are influenced by human activities, they can be considered indicators of the deteriorating relationship between humans and ecosystems like the Chesapeake Bay. Fish kills in the Chesapeake Bay during 1996 and 1997 -- as well as 1997 reports by Chesapeake fishermen of fatigue, headache, respiratory problems, diarrhea, weight loss, and memory difficulties -- spurred the Maryland State Department of Health and Mental Hygiene in August 1997 to enlist researchers at the University of Maryland and the Johns Hopkins School of Public Health in an investigation of Pfiesteria. Scientists still don't know exactly what Pfiesteria is, why it is toxic, or what causes it to bloom explosively. The paper concludes with a discussion of how public health policy should be framed during a period of such scientific uncertainty.

"Toxic chemicals: Can What We Don't Know Harm Us?" Author: Peter L. deFur, PhD, affiliate associate professor, Center for Environmental Studies, Virginia Commonwealth University, Richmond VA. We don't know the effects of low-level exposure to the 500 chemicals now polluting the Bay. Answering these questions entails keeping track of pesticides and fertilizers used in agriculture; chemicals from landfills and parking lots; heavy metals in Bay sediments stirred up during dredging; and the traces of persistent, bioaccumulative chemicals such as DDT and chlordane. The author asserts that because even "neutral" chemicals can have unexpected effects, we must operate on the assumption that one more chemical, one more exposure, or even more of the same chemical, will cause harm, and must shift the burden of proof to those proposing an activity to prove no harm. The automatic default must not allow further releases, emissions, or uses when we cannot predict the consequences.