Browsing by Author "National Oceanic And Atmospheric Administration"
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Item National Status & Trends Program(1988-11) National Oceanic And Atmospheric AdministrationSince 1984, the National Oceanic and Atmospheric Administration‘s (NOAA) National Status and Trends (NS&T) Program has analyzed samples of surface sediment collected at about 200 coastal and estuarine sites throughout the United States. The chemical contaminants measured are chlorinated pesticides, polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), and 12 trace elements. Sediment characteristics such as grain size, which affect contaminant concentrations, have also been quantified. With few exceptions, the higher levels of contamination have been found among the 175 sites where the sediment is muddy rather than sandy. Most of the highest concentrations for any particular contaminant have been at the 20 sites near Boston, New York, San Diego, Los Angeles, or Seattle. Despite being sandy, sediments at two Long Island Sound sites showed high levels of PAHs. Except for some sites near the Florida cities of Jacksonville, Tampa, Panama City, and Ft. Walton Beach, levels of contamination at sites in the Gulf of Mexico and in the southeastern United States were relatively low.Item National Status & Trends Program for Marine Environmental Quality(1991-04) National Oceanic And Atmospheric AdministrationThe National Oceanic and Atmospheric Administration’s (NOAA) National Status and Trends (NS&T) Program has analyzed samples of surface sediment collected at almost 300 coastal and estuarine sites throughout the United States since 1984. When the first NS&T report on sediments (NOAA, 1988) was written, only about 200 sites had been sampled. This second report is based on more data. Even with this larger data set, the original observation holds that most of the highest concentrations for any particular contaminant are found at sites nearthe urban areas of Boston, New York, San Diego, Los Angeles, and Seattle. The overall concentration distributions for each contaminant are approximately lognormal, allowing a definition of “high”concentrations as those exceeding the mean plus one standard deviation of the lognormal distribution. Those “high” concentrations are useful for comparisons within the NS&Tdata set and with other reports on sediment contamination. The “high” concentrations in units of pg/g of dry fine-grained sediment for each contaminant are (in parentheses): Ag (1.2), As (24), Cd (1.2), Cr (230), Cu (84), Hg (0.49), Pb (89), Sn (8.5), Zn (270), LMWPAH (l.O), HMWPAH (3.0), tDDT (0.037), and tPCB (0.20).