3.4 Comparison with international benchmarks
A comparison of the results against current international goals found no substance exceeded the goals at any time. Only the concentrations at some sites of benzene and 1,3-butadiene came near to reaching the current goals. At all sites the annual average concentrations of benzene were below the UK (2003) goal of 5 parts per billion by volume (ppbV). Even the more stringent long-term European Commission annual average goal of 1.5 ppbV (to be achieved by 2010) was met at all sites, except the Sydney CBD with its heavy traffic. The concentrations of benzene in outer urban Sydney, Newcastle and Wollongong were also well below both of these goals (see Figure 3).
Figure 3: Highest annual average benzene levels in NSW (1996-2001) compared with future EC and UK goals
The levels of 1,3-butadiene were below the UK annual average goal of 1 ppbV at all sites. The highest annual average of 0.6 ppbV was also measured at the Sydney CBD site (see Figure 4).
Figure 4: Highest annual average 1,3-butadiene levels in NSW (1996-2001) compared with future UK goal
The results for benzene and 1,3-butadiene in this study are broadly consistent with the levels found in comparable overseas locations.
The European Commission goal for benzene is based on fuel control measures which came into effect in Europe in 2000 when a 1% benzene limit in petrol was put in place, allowing a 10-year lead time to achieve the goal. Australia will introduce a 1% benzene limit in 2006.
Page last updated: 26 February 2011