The biological and toxicological importance of molybdenum in the environment and in the nutrition of plants, animals and man

Abstract

The molybdenum intake by German and Mexican adults (21 test populations) aged 20 to 69 years with mixed and ovolactovegetarian diets were determined. Each test group consisted of at least 7 women and 7 men, which collected all consumed foodstuffs and beverages as visually estimated duplicates on 7 successive days. The balance studies were carried out with 8 test populations (women and men) with mixed and ovolactovegetarian diets. People with mixed diet in Germany consumed, on average, 89 (women) and 100 μg Mo/day (men), whereas in Mexico they took in 160 and 210 μg Mo/day, respectively. German ovolactovegetarians consumed ∼175 μg Mo/day. Male adults of Germany consumed 21% more molybdenum than women. This difference is the result of a 24% higher dry matter intake by males. The residence place, its geological origin and time of examination influenced the molybdenum intake significantly (60–115 μg Mo/day). The normative molybdenum requirement of adults amounts to 25 μg/day, with women needing 20 and men 25 μg/day. As a rule approximately only one-third of the absorbed molybdenum is excreted renally, the rest faecally. Breast feeding mothers excreted 11% via milk, 56% faecally and 33% renally. The apparent absorption rate of molybdenum amounted to 37% in humans with mixed and vegetarian diets, whereas it reached 44% in breast-feeding mothers. The calculation of molybdenum consumption (basket method) overestimated the molybdenum intake by 50% in comparison to chemical determination by the duplicate portion method.