The Bioeffects program is a nationwide program of environmental assessment designed to describe the current status of environmental quality in our nation’s estuarine and coastal areas. Field studies examine the distribution and concentration of over 150 chemical contaminants in sediments, measure sediment toxicity, and assess the condition of bottom-dwelling biological communities. This information is integrated into a comprehensive assessment of the health of the marine habitat.
Why We Care
Bioeffects projects are designed to assess the spatial distribution and magnitude of effect of chemical contamination, and develop indicators of environmental contaminant exposure in water bodies, ranging from small estuaries to large bays and coastal areas. Data are applicable to environmental risk assessments, damage assessments, and for planning future resource management and restoration activities. Using consistent methods over the life of the program allows for comparison of the magnitude and extent of contaminant effects relative to other locations throughout the U.S., and over time. All data are generated following strict performance-based quality control and quality assurance protocols. Data are available to regional, federal, state and local resource managers and the public via publications, presentations and a website data portal.
What We Did
Bioeffects studies are generally a one-time, intensive sampling effort. All sites within the study area are sampled for chemical analyses, and sea floor community assessment in as short a time as possible, so the data reflect a snapshot of the condition of the entire system at a point in time. In brief, field procedures include sampling sediment and the overlying water column. Two sediment samples are taken at each site using what is known as a “Young-modified Van Veen grab sampler.” Only the upper 2–3 cm of the sediment is retained in order to assure collection of recently deposited materials. The sediment samples are thoroughly homogenized in the field and are then subdivided for distribution to various testing laboratories. A third sample is taken for sea floor community analysis. A profile of water quality in the water column is measured to include standard variables such as temperature, depth, salinity, dissolved oxygen, etc. Detailed descriptions of the sampling techniques and procedures are available by contacting the project manager.