Gladstone air study 2009-2010 : Monitoring for polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzo-p-dioxins (PCDDs) furans (PCDFs) and polychlorinated biphenyls (PCBs).

摘要

EXECUTIVE SUMMARY The Gladstone Air Study was initiated as part of the Clean & Healthy Air for Gladstone (CHAG) project established by Queensland Health and the Department of Environment and Resource Management. This project arose in response to community concern regarding the perceived cumulative impact of industrial growth in the Gladstone region on air quality and the consequences for human health. The Gladstone Air Study, as a component of CHAG, aimed to provide data which will profile the levels and types of specific hazardous air pollutants (HAPs) and allow for an assessment of the subsequent health risks they pose to humans living and working in the Gladstone region. The specific HAPs, which were targeted in the Gladstone Air Study, included polycylic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs). These HAPs were monitored over a twelve month period between February 2009 and January 2010. Monitoring was conducted on a monthly basis at two sites (South Gladstone and Targinie) and in winter (June/July 2009) and summer (December 2009) at an additional four sites (Boyne Island, Clinton, Auckland Point, and Boat Creek) within the Gladstone Air Monitoring Network. Some additional monthly monitoring occurred at Boyne Island in October and November. Overall this monitoring for HAPs in the Gladstone region has found that the concentrations of PAHs, PCBs and PCDD/Fs in air: „h are within available health based guidelines (National Environmental Protection Measure (Air Toxics) monitoring investigation levels) established for benzo[a]pyrene as a marker for PAH exposure; „h do not contribute significantly to nor exceed available international exposure standards for intake of ¡§dioxin-like¡¨ PCBs and PCDD/Fs recommended by the National Health and Medical Research Council within Australia; and „h are consistent with, or lower than the concentrations measured in other parts of Australia. There was however considerable variation in the concentrations and profiles of specific HAPs within the Gladstone region. Overall the maximum concentrations of all PAH markers of exposure for the region occurred at the South Gladstone site and in summer. The maximum monthly and annual average concentrations of benzo[a]pyrene at this location were 0.14 ng.m-3 and 0.046 ¡Ó 0.045 ng.m-3 respectively, while the regional average concentration (all data) was 0.032 ¡Ó 0.034 ng.m-3. These average concentrations are approximately an order of magnitude lower than the annual average monitoring investigation level of 0.3 ng.m-3 established under the National Environmental Protection Measure (Air Toxics). The concentrations of benzo[a]pyrene in the Gladstone region are similarly lower than the concentrations measured previously in ambient air in major cities in Australia. The maximum monthly concentrations of PCDD/Fs and ¡§dioxin-like¡¨ PCBs expressed as World Health Organization toxic equivalent air concentrations (WHO05 TEQDF and WHO05 TEQP respectively) occurred at South Gladstone in summer (12 fg.m-3) and Boyne Island in winter (0.40 fg.m-3). South Gladstone also had the highest annual average WHO05 TEQDF (4.5 fg.m-3) in the region while Auckland Point had the highest average WHO05TEQP (0.34 fg.m-3). The regional average WHO05 TEQDF and WHO05 TEQP were 2.3 fg.m-3 and 0.14 fg.m-3 respectively. The regional average and range of 2.3 ¡Ó 2.4 (0.24 ¡V 12) fg.m-3 for WHO05 TEQDF measured in the Gladstone region are very consistent with the finding of the National Dioxin Program Page 2 conducted in 2003 which indicated that the concentrations in ambient air in Australia are very low by world standards. For example WHO98 TEQDF average (and range) concentrations of 8.9 (0.73 ¡V 41), 1.5 (0.27 ¡V 4.04), 1.1 (0.11 -121), 2.8 (0.29 ¡V 13) fg.m-3 were reported for Eagle Farm in Brisbane, Mutdapilly south west of Brisbane, Cape Grim in Tasmania and Berrimah in Darwin, respectively. The dominant PCDD congener across the Gladstone region was octachlorodibenzo-p-dioxin (OCDD) which is approximately 10 000 times less potent than the reference dioxin congener 2,3,7,8-tetrachnlorodibenzo-p-dioxin (2,3,7,8-TCDD). Average OCDD concentrations ranged from 30 ¡Ó 24 fg.m-3 at Boyne Island to 78 ¡Ó 57 fg.m-3 at South Gladstone. 2,3,7,8-TCDD was only detected at the South Gladstone site in concentrations ranging from 0.50 fg.m-3 to 2.9 fg.m-3. The highest concentrations of PCDF congeners occurred at Targinie and Boat Creek in the north of the region. These elevated PCDF profiles, where maximum concentrations were observed in winter, may reflect some preservation of wood smoke source profiles within the ambient profiles at these locations. The dominant non-ortho PCB congener in the Gladstone region was PCB 77. The average concentrations for this congener ranged from 10 fg.m-3 at Boat Creek and Targinie in the north of the region to 55 fg.m-3 at Auckland Point. The most potent ¡§dioxin-like¡¨ PCB monitored was the non-ortho congener PCB 126 which has an WHO05 TEF of 0.1 (10 times less potent than 2,3,7,8-TCDD). This congener was present at relatively low concentrations across the region with average concentrations ranging from 0.75 ¡V 2.8 fg.m-3 at Clinton and Auckland Point respectively. The most dominant mono-ortho ¡§dioxin-like¡¨ PCB was PCB 118 which was present at maximum values ranging from 517 fg.m-3 at South Gladstone to 1321 fg.m-3 at Auckland Point. It should be noted that this congener was not detected in any of the monitoring periods at sites to the north of Gladstone (Targinie and Boat Creek). While PCB 118 was detected at relatively high concentrations compared to many of the other ¡§dioxin-like¡¨ PCBs, all of the mono-ortho PCBs exhibit a relatively low potency with respect to 2,3,7,8-TCDD.