Trace element concentrations in human blood from the U.K., measured by Hamilton et al., are found to be correlated to those of atmospheric aerosol from the U.K., or to an aerosol composition averaged over the globe. The correlation to aerosol is much stronger than to crustal rock or sea water. Elemental enrichment factors for blood are all equal to or greater than those for aerosol. Two possible reasons for the correlation are advanced: aerosol is probably a major source of the trace elements which enter the food chain, and aerosol samples the earth's surface where the food chain originates. The present finding suggests that aerosol plays a major role in the global cycling of the trace elements which enter the blood, with important implications for human health.