Surface waters biological effects

Nozaki Y, Zhang J, Takeda A (1997) °Pb and °Po in the equatorial Pacific and Bering Sea the effects of biological productivity and boundary scavenging. Deep-Sea Res II 44 2203-2220 Nozaki Y, Dobashi F, Kato Y, Yamamoto Y (1998) Distribution of Ra isotopes and the °Pb and °Po balance in surface waters of the mid Northern Hemisphere. Deep-Sea Res. 145 1263-1284 Pates JM, Cook GT, MacKenzie AB, Anderson R, Bury SJ (1996) Determination of Th-234 in marine samples by liquid scintillation spectrometry. Anal Chem 68 3783-3788... 

The composition of leachate is important in determining its potential effects on the quality of nearby surface water and groundwater. Contaminants carried in leachate are dependent on solid waste composition and on the simultaneously occurring physical, chemical, and biological activities within the landfill. The quantity of contaminants in leachate from a completed landfill where no more waste is being disposed of can be expected to decrease with time, but it will take several years to stabilize. 

The relationship between incidence of lead shot in waterfowl gizzards and biological effects varies widely and is probably a function of shot availability caused by differences in shooting intensity, size of pellets, availability of grit, firmness of soil and sediments, and depth of surface water (Street 1983). Also, lead accumulations and the frequency of avian lead toxicosis following... 

The major in situ process that results in the formation of H202 is undoubtedly photochemical (e.g., 12, 15, 49, 50). Photochemical formation of H202 in fresh and salt waters probably results from the disproportionation of the superoxide ion radical, 02 (8, 9, 15, 51, 52). The kinetics of superoxide disproportionation are well established (53), and its steady-state concentration can be calculated. Because of the known effects of superoxide ion in cells (47), its presence in surface waters may be important in biologically mediated processes. However, other sources, such as biological formation (e.g., 45, 54), redox chemistry (21, 24, 29, 31, 32), wet (e.g., 55) and dry (50, 56, 57) deposition, and surfaces (e.g., 58) may also be important. 

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