Showing papers on "Water environment published in 1973"

Drug Resistance of Coliform Bacteria in Hospital and City Sewage

Abstract: The number and properties of drug-resistant coliform bacteria in hospital and city sewage were compared. There was little difference in the counts of organisms with nontransferable resistance to one or more of 13 commonly used drugs. An average of 26% of coliforms in hospital waste water had transferable resistance to at least one of the drugs ampicillin, chloramphenicol, streptomycin, sulfonamide, or tetracycline as compared to an average of 4% in city sewage. R(+) bacteria in the hospital discharge were also resistant to a broader spectrum of drugs than those in city sewage. In both effluents, the occurrence of fecal Escherichia coli among R(+) coliforms was twice as high as among coliforms with nontransferable resistance. Resistance was transferable to Salmonella typhi, and such drug-resistant pathogens in the water environment could be of particular concern. The significance of the results with regard to environmental pollution with R(+) bacteria and the dissemination of these organisms is discussed.

Interactions of ferric and ferrous irons and organic matter in water environment

Abstract: Coprecipitation of organic matter with ferric and ferrous hydroxide, and iron holding in solution containing organic matter were experimentally studied. The dissolved organic matter from bacterial degradation of green algae was used. The results of the experiments showed that ferrous iron, as well as ferric iron, coprecipitate organic matter under reduced conditions, and that ferric and ferrous irons selectively coprecipitate proteinous materials. On the contrary, pigment and lipid materials are rarely coprecipitated, and hold ferric iron in dissolved form probably by forming water soluble iron-organic complexes. These results show the significance of the interaction of organic matter and iron in the cycle of them in the hydrosphere.

Public Health Aspects of Organics in Water

Abstract: Conservationists in California have adopted two goals relating to the water environment: first, they are opposed to new water-resource development; second, they are opposed to discharging wastewaters into the water environment. In pursuit of both goals, the conservationists are strongly advocating wastewater reuse. With relation to the second goal, their position, not explicitly stated, is "don't discharge sewage into receiving waters and possibly damage the environment, drink it!" The Resources Agency of California in a preliminary statement of environmental goals and policy, not yet officially adopted, commits the state to wastewater reuse "as part of a comprehensive water supply and management program." Currently a number of specific project proposals' are being developed for major ground-water replenishment with reclaimed wastewater. In some instances, the ground-water basins at equilibrium would be almost 100 per cent reclaimed water. Other proposals, still in very preliminary form, would introduce reclaimed sewage into existing domestic-water impoundments and even (in the extreme) utilize treated sewage directly as a portion of the raw-water supply with or without dilution. Four factors appear relevant in connection with the utilization of reclaimed wastewaters as a significant portion of community domestic water supply. They are microorganisms, total minerals, mineral toxicants, and stable organics. The focus of this article is on the stable organic fraction. Two questions arise: what is known of the characteristics of these organics, and how significant are they to man's health?

Chemical analysis of the environment and other modern techniques

Abstract: Trace Metals in the Environment.- Pitfalls in the Determination of Environmental Trace Metals.- Atmospheric Trace Metal Studies.- Trace Metal Concentration Factors in Aquatic Ecosystems.- Human Trace Metal Burdens: Pathways, Uptake, and Loss.- Relation of Trace Metals to Human Health Effects.- Pesticides in the Environment: Recently Discovered Analytical Problems.- Polychlorinated Biphenyls: Their Potential Interference with Pesticide Residue Analyses and Analytical Status.- Analysis of Pesticides in Air.- The Significance of Pesticide Contaminants.- Gas Chromatographic Analysis of Pesticide Residues Containing Phosphorus and/or Sulfur with Flame Photometric Detection and Some Ancillary Techniques for Verifying their Identities.- The Determination of Anions in Water.- Some Partially-Solved Problems in Anion Analysis.- Spectrophotometry, Spectrofluorometric, and Atomic Absorption Spectrometric Methods for the Determination of Anions.- Fluoride Analysis in Seawater and in Other Complex Natural Waters Using an Ion-Selective Electrode - Techniques, Potentialities, Limitations.- Analytical Techniques for Nutrient Anions and Other Pertinent Substances in the Water Environment.- Current Topics in Pharmaceutical Analysis.- Analytical Requirements of Automated Pharmaceutical Analysis.- A Look Ahead Towards Possible Future Analytical Requirements by FDA.- Data and Information Handling Systems in the Pharmaceutical, Analytical, and Quality Control Environments.- Panel Discussion.- Semantics in Specifications for Drugs.- What Problems Does One Introduce When Different Criteria for Acceptability of Unfinished Actives vs. the Formulated Actives Are Utilized?.- Analytical Methods for Stability Samples - What Should They Tell you?.- Tests to Monitor the Acceptability of Raw Materials - Are They Adequate?.- Automated Analysis.- Automation in Microchemistry: Automatic CHN Analyzer Case History.- Methodology Problems in Automated Analyses.- Growth Path for Computers in Automated Analyses.

An Ultrasonic Radiation Calorimeter

Abstract: This paper describes a constant temperature environment calorimeter for the absolute measurement of ultrasonic power. This design uses a variation of the classical calorimetric procedure of power measurement as applied specifically to ultrasonic transducers. This measurement technique has advantages over other methods in that it is the least affected by beam shape and pulse duration. The calorimeter consists of a conical shaped calorimeter cup mounted in an outer brass cylindrical container. The calorimeter is placed in a water bath, which provides both a constant temperature environment and an effective medium for the propagation of ultrasound. The calorimeter cup is filled with Dow Corning 710 silicon fluid, which is an effective absorption medium. It has a 112‐in. entrance window of gold coated nylon separating the silicon fluid from the water bath. The gold film is used as a resistance heater to maintain quasi‐adiabatic conditions between the silicon absorbing fluid and the water environment at the entrance membrane. The temperature difference between the silicon absorbing fluid and the outer brass cylinder is measured with a bank of chromel‐constantan thermocouples. This measured temperature difference is a measure of the ultrasonic power. Calibration of the system is accomplished with a constant resistance heating coil immersed in the Dow Corning 710 absorbing fluid.

Fate of oil in a water environment, phase I. Volume I. A review and evaluation of the literature. [Petroleum]

Abstract: This report presents the results of an evaluation of the literature to determine what is known about the fate of oil released to the water environment. More than 10,000 journals and data sources were reviewed by computer and manual search methods in order to locate information. From this, about 550 pertinent articles were critically evaluated to determine mass balance relationships. The major areas of concern, or first order reservoirs, were the atmosphere, water surface and water column, bottom sediments and shore zone. The evaluation of these reservoirs included a critical review of the biological factors which change and remove hydrocarbons from the water environment and the role of the biota as a physical reservoir.

Analytical Techniques for the Detection of Nutrient Anions, Phosphates and Nitrates in the Water Environment

Abstract: Eutrophication refers to the natural aging processes of lakes It carries two connotations: The increase in nutrients such as nitrates and phosphates leads to a greater biological productivity and eventually the conversion of a lake to dry land The effects of eutrophication cause changes in plant and animal species present in the water body, which may be objectionable The former development as a natural process is long term, although man!s activities may greatly increase its rate of attainment The latter result, however, is the undesirable effects, which may be the appearance of algal blooms and the loss of desirable fish species leading to destruction of recreational and drinking water resources (1) Nutrients and phosphates are responsible for algal blooms and their measurement in natural waters is important The degradation and aging of rivers and streams, although not universally referred to as eutrophication, is considered a somewhat allied process and nutrients play a similar role as in the eutrophication of lakes and ponds (1)