Issue 2, 2002

Abstract

The isotopic composition of lead collected with grass samples taken over the period 1989–2001 from plots at two upland locations (Glensaugh in north east and Hartwood in central Scotland) has been determined using thermal ionisation mass spectrometry. Although marked reductions in lead concentrations in grass were observed at Glensaugh in the initial three years, subsequently concentrations have remained relatively constant (1–3 µg g−1) in all plots to the present day. The one exception was a roadside plot at Hartwood which showed a large reduction from 1.0 µg g−1 in 1999 to 0.2 µg g−1 in 2000 following the abolition of petrol lead in the UK at the beginning of 2000. The total concentrations at this plot were consistently lower than those found at plots away from road traffic but exposed to the prevailing wind direction. The 206Pb/207Pb ratio increased steadily at all the plots throughout the period of the study indicating the reducing influence of petrol lead but the changes were not as great as might be expected with the decrease in the use of leaded petrol. Assuming the collected lead had only two sources, petrol lead and a diffuse background “industrial” lead, the proportion of petrol lead was only in the range 17–69% for roadside samples and 0–39% in other samples. A substantial proportion of deposited lead, therefore, now has its origin other than in petrol. Mixing curves indicate that whereas the lead deposited at Glensaugh could be defined by only two end members, that at Hartwood needs more than two components in the mixture. The results also suggest that although petrol lead has been eliminated, traffic is still a source of lead and another source defined as “traffic lead” should be considered.

Article information

Article type
Paper
Submitted
24 Oct 2001
Accepted
08 Jan 2002
First published
05 Feb 2002

J. Environ. Monit., 2002,4, 291-299

Isotopic characterisation of lead deposited 1989–2001 at two upland Scottish locations

J. R. Bacon, J. Environ. Monit., 2002, 4, 291 DOI: 10.1039/B109731H

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements