An assessment of the effectiveness of lead pollution reduction strategies in North Lake Macquarie, NSW, Australia

摘要

The North Lake Macquarie area of NSW, Australia, principally the suburbs of Boolaroo, Argenton and Speers Point, has been significantly polluted by lead emissions emanating from the Pasminco Metals Smelter (Cockle Creek). A lead accessibility reduction program has been carried out in North Lake Macquarie since 1991. The primary measure of success for the program is reduced blood lead levels, particularly in children. From 1991 to 2000 average child blood lead levels have decreased from 11 to 7.5 mug/dl. However, the lead accessibility reduction programs had failed to eliminate child blood lead levels that exceed the National Health and Medical Research Council maximum goal of 10 mug/dl, and a number of children still retain blood lead levels > 25 mug/dl. Many factors have contributed to this failure, notably the continued presence of airborne high lead pollutants in ambient air, dusts and soil in residential areas. Significant reductions in lead mass emissions from 92 tonnes per annum (p.a.) in 1988 to approximately 15 tonnes p.a. to September 2000 have been achieved by the smelter operator. However, the reductions have been insufficient to ensure that ambient air quality consent conditions of 1 mug/m(3) are achieved in the residential areas surrounding the smelter. Sampling by the smelter operator also provides confirmation of continued deposition of high lead dusts in residential areas. The continued dust deposition places a high burden on the local community which must maintain obsessive levels of household cleanliness in order to minimise lead uptake from dusts deposited within the home and community. Evidence exists of institutional failure that may also have limited the success of the program. These failures include the use of inappropriate standards and non-approved techniques in remediation, lack of coordination between various arms of government and an unwillingness to enforce consent conditions'. The smelter operator has also failed to proactively seek changes which would minimise community harm. It is suggested that for child blood lead levels to be further reduced it may be necessary to impose added restrictions on smelter emissions. Firstly, however, current emission requirements should be mandated and methodologies for remediation of historical lead depositions should also follow accepted standards and practices to maximise the benefits of the work to the affected community. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 34]