Comparative studies of atmospheric trace elements: improvements in air quality near a copper smelter.

Measurements of trace element concentrations, including heavy metals in the atmosphere near a copper smelter in Port Kembla, New South Wales, have shown improvements in air quality, attributed mainly to modernisation of the plant, with more than 85% decrease (for each element) in airborne Cr, Zn, Se, Ag, Cd, Sb, Au and Pb, associated with 74% reduction in Cu concentration. This data was obtained by analysis of air particulate sampled in 2001-2002 for comparison with measurements at the same location in 1978. As expected, measurements of Na and Cl derived from the marine aerosol at this coastal location showed no corresponding change. The recent analysis of air particulate shows significant correlations between the monthly concentrations of Cu, Zn, Se, Ag and Pb, associated with industry, hence giving a high enrichment in airborne particulate by reference to the element/Sc ratios in 'average' soil. These enrichments, shown by heavy metals in particular, were two orders of magnitude greater than the values recorded in the atmosphere of rural areas; however, it is clear that air quality at Port Kembla is much improved and predominantly related to the modernisation of the smelter.

The effect of reducing petrol lead on airborne lead in Wales, U.K.

Airborne lead has been measured at four urban, one semi-urban and one rural site in Wales during 1984, 1985 and 1986 to assess the effect of the reduction in lead additives in petrol which was required by an EC Directive at the beginning of 1986. The results showed a 52-61% fall in air lead in accord with the 63% reduction in petrol lead.

Trace elements in the atmosphere.

The distribution and behaviour of particulate trace elements in the atmosphere have been studied by continuous measurements for 5 years at seven non-urban sites in the United Kingdom. Samples have been taken regularly of airborne dust, rainwater and dry deposition: these have been analysed for up to 36 elements. Concentrations of trace elements vary considerably between sites but the relative concentrations are among uniform: this suggests similarity of origin or good atmospheric mixing. By comparing the relative concentrations with those in soil it is possible to differentiate between trace elements that are derived from soil and those that may be attributed to industrial activity. This classification is supported by estimates of the particle sizes in air. The deposition of trace elements can be related to the concentrations presnet in soil and to the annual removal by crops. Retrospective analyses of stored samples from one site describe the history of trace element concentrations in air since 1957. The sea surface is considered as a possible source of atmospheric trace elements.