United States, coastal rivers

The first reports of plastic in the North Atlantic indicated the presence of 50-12,000 particles/km in the Sargasso Sea in 1972 (52) and from 0-14.1 particles per m in coastal waters of southern New England (42), where the main source was river-borne effluents from plastic fabrication plants (44). Plastic objects discarded from boats and from recreational activities on beaches were the main sources of debris in Narragansett Bay, being deposited at a rate of 9.6 g m of beach front per month (53). During a detailed survey off the southeast coast of the United States (43, 54), fragments of plastic were present in about 70% of the samples collected from the waters of the continental shelf, the continental slope and the Gulf Stream between Florida and Cape Cod, 50% of those from the Caribbean Sea, and 60% of those from the Antilles Current. Since unprocessed plastic was more prevalent in continental shelf waters and fabricated objects were common offshore but rare near land, the authors surmised... 

Hexachlorobutadiene has been detected in some surface waters but the incidence of detection is low. It was detected in 0.2% of 593 ambient water samples in the STORE database with a median level for all samples of less than 10 ppb (Staples et al. 1985). Hexachlorobutadiene was detected in 1 of 204 surface water sites sampled across the United States with a concentration of 22 ppb (Ewing et al. 1977). Low levels of hexachlorobutadiene were detected in the Niagara River at 0.82 ppt (Oliver and Charlton 1984). Hexachlorobutadiene was not detected in rainwater (Pankow et al. 1984) or urban storm water runoff (Cole et al. 1984) in a number of U.S. cities. It has not been detected in open ocean waters however, the coastal waters of the Gulf of Mexico were reported to contain 3-15 ppt (Sauer 1981). 

Meade, R.H., 1981. Man s influence on the discharge of fresh water, dissolved material and sediment by rivers to the Atlantic coastal zone of the United States. In 3.M. Martin, 3.D. Burton and D. Eisma (eds), River Inputs to Ocean Systems. UNEP and UNESCO, Switzerland, pp. 13-17. 

K.C. Beck, J.H. Reuter and E.M. Perdue, Organic and inorganic geochemistry of some coastal plain rivers of the southeastern United States, Geochim. Cosmochim. Acta 38 (1974) 341-364. 

Gao, H.Z., and Zepp, R.G. (1998) Factors influencing photoreactions of dissolved organic matter in a coastal river of the southeastern United States. Environ. Sci. Technol. 32, 2940-2946. 

Notwithstanding unequivocal benefits associated with the acceleration of the global N cycle in terms of satisfying societal demands for food and fuel, the negative environmental consequences to estuaries and coastal seas caused by over-enrichment of nitrogen are significant (Howarth and Marino, 2006 Rabalais, 2002). For example, two-thirds of the coastal rivers and bays in the United States are moderately to severely... 

A freshwater stream may look sparkling and clean, but it s probably not safe for drinking. Many rivers and lakes in the United States are polluted. Bacteria and viruses enter water supplies through contamination by sewage and industrial wastes. Wastes from landfills and mines leak into groundwater reservoirs. Pesticides, herbicides, and fertilizers are picked up by rainwater and carried into streams. Streams flow into rivers, and rivers empty into oceans. In addition, coastal cities pump waste directly into the oceans. For this reason, much of the oceans pollution is found along the coasts of continents. 

The first fish consumption advisories were issued in the United States in the early 1970s in response to the discovery of mercury in fish in waters of southeast Michigan downstream of an industrial discharge of mercury. As more and more states tested fish for contaminants over the last 30 years, consumption advisories spread to nearly every state in the nation. In 2002, the US Environmental Protection Agency s National Listing of Fish and Wildlife Advisories included 2800 advisories in 48 states, the District of Columbia, and the US Territory of Samoa. The 2800 advisories in the national listing cover almost 33% of the nation s total lake acreage and 15.3% of the total river miles. Twenty-seven states and the District of Columbia have issued statewide advisories for lakes, streams, or coastal waters. 

Figure 11. Retarding effects of added desferal (0.3 mM) on the photochemical production of Die in a coastal river of the southeastern United States [59]. DIC concentration without ( ) and with (O) added desferal. The effect is attributed to formation of unreactive Fe(iii)-desferal complexes.

At low pH (ca. 3-5), H2O2 can be consumed through iron cycles associated with the oxidation of fulvic acids involving the photo-Fenton reaction (reaction 8) [84]. As previously discussed, reactions (8) and (9) may be important in humic-rich natural waters at low pH such as in black-water rivers of the southeastern United States (e.g., Suwanee River, GA), but their importance in marine waters at higher pH (typically ca. pH 8.2) is unlikely except for some organic rich coastal environments (vide supra). 

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