The Health Effects of Low-Contact Water Activities in Fresh and Estuarine Waters

Four studies were carried out at separate locations to investigate the relationship between health effects and low-contact water sports, and intensive microbiological sampling was conducted in parallel to the health studies at each site. The two sports examined were marathon canoeing and rowing.
The extremes of water quality were at the estuarine sites on the River Torridge, where pollution levels varied from a geometric mean faecal coliform value of 62/100 ml at the Appledore/Instow site to 4613/100 ml at the Bideford site.
A comparison of 'exposed' and 'unexposed' groups, 5–7 days after exposure, showed that the health effects of low-contact water sports are minimal, within the water quality ranges which were studied.     

DROP SIZE DISTRIBUTION OF LITHIUM AMALGAM PRODUCED BY MERCURY JET CATHODE

The drop size distribution of the lithium amalgam produced by mercury jet cathodes was studied experimentally. Electrolysis was done in aqueous solution, 3 mole LiOH per liter, at ambient temperature. Jets were obtained by passing mercury through small orifices made in a Plexiglas plate. The orifice diameter was varied from 28 to 70 μm, the hydrostatic mercury pressure from 200 to 800mmHg, and the electrolysis voltage from 0 to 6 V. An optical method for drop size determination was carried out.

Within the limits of experimental errors, a unique distribution was obtained for all cases. The volume fraction vs. drop diameter curve resembled a Gaussian distribution having the mean diameter D¯v = 209.7 μm and the spread σ_v =39.1 μm.