Concentrations of lead, mercury and cadmium in bulk precipitation were measured at four heights along an 866 metre elevational gradient in New England, USA during four months of 1971. Weighted average concentration of lead, determined by atomic absorption spectrophotometry, was 13·4 μM/l. The mean deposition rate was 54 μM/m2/day and an extrapolated value for mean annual deposition was 20 mg/m2, eighteen times higher than that reported as derived from marine air in the mountains of California, but lower than that reported in urban areas where airborne heavy metals are released in high concentrations by human activities. These values suggest that New England receives a relatively high deposition of lead due to its continental downwind position. Much of this lead probably originates from human activities. Cadmium and mercury concentrations averaged 0·6 and 0·06 μM/l and deposition rates averaged 2·4 and 0·2 μM/m2/day, respectively. It is possible that these bulk precipitation measurements underestimate the total deposition at high elevations since they do not account for cloud water condensation and aerosol impaction.
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