Variation of cadmium concentration in Swedish wheat and barley. An indicator of changes in daily cadmium intake during the 20th century.

In order to evaluate whether or not an increase in daily cadmium intake may be taking place, 75 wheat samples (spring wheat and fall wheat) harvested from the same "nonpolluted'' farm fields between the years 1916 and 1972 were analyzed. The individual scatter was large but a significant (Psmaller than.05) tendency toward increasing concentration with time was evident for fall wheat. A similar tendency was found for spring wheat, through not a statistical significance. This increase may be explained by general air contamination or the cumulative effect of fertilizers. There was a clear covariation in cadmium concentrations of differenc genotypes of wheat and barley harvested in the same year despite yearly variations in average concentration.