While the problem of the degradation and pollution of our planet's salt waters has existed for millennia, indeed for all the time mankind has lived by water, it has become a matter of great concern within the past fifty years, as the human population of the planet has grown rapidly. Perhaps only air is more important to life on Earth than water, but even this point may be argued. The analysis of water, specifically fresh and salt water bodies upon which humans depend
for daily drinking water, food, transportation, industrial feedstock, resources, and livelihood, becomes more important each year as these bodies are stressed by human interactions, use, and depletion. The quality of fresh water, littoral waters, and even deep ocean waters has thus drawn increasing
attention in the recent past from academia, industry, government and the general public and this makes it a timely symposium subject, despite an established history of research into the substance, a number of well-written issues of various laymen's journals, and even growing coverage of the subject in the news media.

To perform the analyses of various waters, and to determine the relative purity of waters and a diverse array of possible contaminants within them, requires numerous different analytical techniques and forms of instrumentation. Researchers who engage in such work often must utilize the talents of those with expertise in fields including: analytical chemistry, biochemistry, inorganic and organic chemistry, microbiology, and botany, as well as chemical and mechanical engineering, to name a few.

The purpose of this volume, based on the symposium of the same name presented at the 241st meeting of the American Chemical Society, in Anaheim, California, in the spring of 2011, sponsored by the Environmental Chemistry Division, is to gather into one place the results and findings of current researchers from widely separated laboratories and centers in different areas. Because of the different aims of these researchers' individual studies, the results gathered here would normally be published
in a rather broadly spread out and diversified series There is definitely a value in presenting these results in a single volume.