Analysis of Radioactivity in Surface Waters—Practical Laboratory Methods

Abstract

Radioactivity was first observed in 1896 by Henri Becquerel who demonstrated that uranium would fog photographic film. Shortly thereafter, it was learned that thorium and actinium were also radioactive and that there were long series of radioactive substances associated with each of these three elements. It was found that the parent elements changed successively from element to element by the emission of alpha, beta, and gamma radiations until some stable end-element was produced; in the case of these three series, the stable end-element was an isotope of lead. These naturally occurring series elements, through their radioactive daughter gases radon and thoron, have an appreciable effect upon background or air activity. These activities are washed down with rain and are carried into water supplies.

Radioactivity in Surface Water

“…Where gross measurements indicate significant contamination, evalu-niques for gross activities in water. Since most stream samples contain suspended matter, these techniques (9,10) provide for the determination of activity levels in both the dissolved and suspended solids. In the procedure developed, an appropriate volume.…”

“…commonly 1-2 liters, is passed through a membrane filter. The membrane is then transferred to a tared counting :c en 10 .ũ 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957…”

Influence of 2,3,5-triiodobenzoic acid, indole-3-acetic acid & method of sample collection on translocation of foliar applied radiocalcium

“…A Nuclear Measurements Corp. Model PCC-10A gas flow internal proportional counter having an over-all efficiency of 40 % was employed for radioactive assay of the samples. This type of equipnment was selected because it possesses a higher, more constantly reproducible efficiency for measurements of weak energy beta radiations than end-window Geiger-Muller counters (7). Frequent background counts were taken to make certain the chamber had not become contaminated from highly radioactive samples.…”

Concepts in Determining Potability of Water After Nuclear Attack

“…An examination of this literature reveals that much emphasis has been placed on past and present problems, but hazards that may occur in the future have been relatively neglected. Maximum permissible concentrations (MPC) of radioisotopes for continuous lifelong intake in time of peace (1) and radioassay techniques for the measurement of radioisotopes at levels below these concentrations have been developed (2). These techniques have protected workers at or near atomic-energy establishments and the public at large from the internal radiation hazards resulting from the ingestion of contaminated water, which emanates primarily from large installations engaged in the manufacture and use of fissionable material.…”

“…In this discussion it will be shown: [1] that many assumptions are necessary in making predictions of fallout distribution and the resulting intensity and composition of radioactive drinking water contamination, [2] that the number and uncertainty of these assumptions make preattack estimates highly doubtful, [3] that emergency assays of water for specific isotopes will be desirable, and [4] how the formulation of safety criteria may be approached.…”