Abstract
Concentrations of bromide in atmospheric particles have commonly been used as an indicator of vehicle-emitted lead, since the two elements are associated in auto exhaust. A depression in the Br/Pb ration from that in resh auto exhaust has generally been interpreted in terms of an industrial contribution to airborne lead, despite the known loss of bromine from airborne particles during aging processes in the atmosphere. In this article the available analytical techniques for determination of Br/Pb ratios in ambient air are reviewed. The possible reasons for variability in Br/Pb ratios are discussed and recommendations made for the evaluation of Br/Pb ratio data.