Abstract：
:IN 1969, Murozumi et al.1 demonstrated that the concentration of lead in Greenland snow had increased by a factor of 200 since ancient times, and concluded that most of this increase was a result of the use of alkyl-leaded petrol. Partly because of these findings, the United States and other western countries limited the use of lead additives in petrol from about 1970. Recently, Boutron et al.2 showed that the lead concentration in Greenland snow had decreased by a factor of ∼7.5 over the past 20 years, and suggested that this was a result of the decline in use of leaded petrol. We present here measurements of the 206Pb/207Pb ratio of the lead contained in the samples studied by Boutron et al. Because aerosols from the atmosphere above the United States are more radiogenic than those from Eurasia, we can trace the relative contributions of these two sources in the Greenland lead over the period analysed by Boutron et al.We find that the United States was a significant source of lead in the 1970s, but it has since declined considerably in relative importance. This decline mirrors the decrease in use of leaded petrol in the United States, confirming the earlier hypothesis.
journal_name
Naturejournal_title
Natureauthors
Rosman KJR,Chisholm W,Boutron CF,Candelone JP,Görlach Udoi
10.1038/362333a0subject
Has Abstractpub_date
1993-03-25 00:00:00pages
333-335issue
6418eissn
0028-0836issn
1476-4687pii
362333a0journal_volume
362pub_type
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