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Updated: Jul 24, 2026
07:38
Milk Collection in the Rat Using Capillary Tubes and Estimation of Milk Fat Content by Creamatocrit
Published on: December 16, 2015
Geographic distribution of selenium in human milk
Archives of Environmental Health
|May 1, 1975
Summary
Selenium levels in human milk averaged 0.018 ppm across the United States. While most values were similar, geographic variations in selenium concentration were observed in human milk samples.
Area of Science:
- Environmental Science
- Human Nutrition
- Trace Element Analysis
Background:
- Selenium is an essential trace element vital for human health.
- Human milk is a primary source of nutrition for infants.
- Understanding selenium levels in human milk is crucial for assessing infant exposure and nutritional status.
Purpose of the Study:
- To determine the mean selenium concentration in mature human milk across the United States.
- To investigate potential geographic variations in milk selenium levels.
Main Methods:
- Milk samples were collected from 241 subjects across 17 states in the United States.
- Selenium concentration was measured using established analytical techniques.
Main Results:
- The overall mean selenium concentration in mature human milk was 0.018 ppm.
- Most individual selenium values ranged narrowly from 0.007 to 0.033 ppm.
- Significant geographic variations in milk selenium content were detected among different cities.
Conclusions:
- Human milk selenium levels in the US are generally consistent but show regional differences.
- These findings highlight the importance of considering geographic factors in human milk selenium studies.
- Further research may be needed to identify the causes of observed geographic variations.
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