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Strontium-90 and cesium-137 in North American milk.
Science (New York, N.Y.)
|June 2, 1961
Summary
Strontium-90 and cesium-137 levels in North American powdered milk correlate with rainfall radioactivity. The consistent strontium-90 to cesium-137 ratios indicate predictable environmental contamination patterns.
Area of Science:
- Environmental Science
- Radiochemistry
- Nuclear Contamination
Background:
- Radioactive isotopes like strontium-90 (Sr-90) and cesium-137 (Cs-137) are environmental contaminants.
- Understanding their distribution in food sources is crucial for public health monitoring.
Purpose of the Study:
- To analyze the concentrations of Sr-90 and Cs-137 in powdered milk across North America.
- To investigate the relationship between these radionuclide levels and rainfall specific activity.
- To determine the variability of the Sr-90/Cs-137 ratio in powdered milk samples.
Main Methods:
- Analysis of over 800 powdered milk samples.
- Sampling conducted at 60 stations across North America.
- Data collection period: 1957-1960.
Main Results:
- Powdered milk concentrations of Sr-90 and Cs-137 generally followed variations in rainfall specific activity.
- The Sr-90/Cs-137 ratios exhibited a low standard deviation of 44 percent across numerous samples.
- This suggests a consistent pattern of radionuclide deposition and uptake.
Conclusions:
- The Sr-90/Cs-137 ratio in powdered milk serves as a reliable indicator of environmental radioactive contamination.
- Findings support the correlation between atmospheric deposition via rain and radionuclide levels in the food chain.
- The study highlights the importance of consistent monitoring of radioactive isotopes in food supplies.
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