Toxics Data Sets

The toxics data base consists of data from CBP-sponsored research and other studies from which the CBP collected historical data on toxics. The toxics data base is divided into three categories: toxic chemical concentrations in Bay organisms (BIOLOGICAL), in sediments (SEDIMENTS), and in the water column (WATER). The data sources include the CBP, private industries, the National Bureau of Standards, state agencies, and the EPA STORET data base. These toxics data cover most of the Chesapeake Bay, and the period of record runs from 1962 to 1981. Data parameters in these files include heavy metals, pesticides, and organic compounds. Data on bottom sediments was retrieved from STORET, the Environmental Protection Agency's National Water Quality data base, and from records held by the Maryland Department of Health and Mental Hygiene.

Three Chesapeake Bay Program investigators, Maynard Nichols, Robert Huggett, and George Helz, also collected data on sediment contamination by heavy metals and toxic organics compounds. The dissolved water column data combines Maryland's "Maryland 106" Data Base, a STORET retrieval of the "Virginia 106" data base and CBP studies. Suspended water column data was collected by researchers with the National Bureau of Standards and Maynard Nichols, Virginia Institute of Marine Science. Virginia shellfish and finfish tissue data was compiled from a STORET retrieval of the Virginia 106 data. Maryland's tissue data was compiled by staff of the Maryland Department of Health and Mental Hygiene, Office of Environmental Programs. The STORET data base contains data which has been compiled from many sources. Due to the large and varied data inputs it was necessary to exclude data of questionable quality. Original outputs revealed that much of the data was coded - frequently as an indication that the metal or organic compound was not present above the detection limit of the testing apparatus. These data were generally marked in STORET by a letter code indicating the value was at or below the detection limit. None of the coded STORET data was retained in the final data set. The Maryland 106 water column data, with the same detection limit coding pattern, was also cleared of those values. Station locations were then mapped and inspected visually. As with the STORET data, the stations were divided into three groups - those characteristic of the Bay segments, "Creek" stations and stations subject to anthropogenic inputs which could unfairly bias the segment or group.

 

Biota

Tributylins

Water

Sediments

Historical Main Page