What and where we monitored
Monitoring dates: May 2005 – September 2005 (winter); December 2005 – March 2006 (summer).
Air toxics monitored: Benzene, benzo(a)pyrene, formaldehyde, toluene and xylene.
Sampling frequency: 24-hour samples once every three days.
Number of samples analysed: Benzene, toluene and xylene — 61; benzo(a)pyrene — 64; formaldehyde — 63.
Location: Eltham East Primary School, Eltham.
Results of monitoring
We monitored benzene, benzo(a)pyrene, formaldehyde, toluene and xylene in a residential area in Eltham.
Concentrations of all air toxics monitored were below the health-based monitoring investigation levels.
Benzo(a)pyrene is a marker for polycyclic aromatic hydrocarbons (PAH), which are commonly associated with combustion sources. The average concentration of benzo(a)pyrene remained below the health-based monitoring investigation level, with most samples recording levels below the chemical analysis detection limit. We found detectable levels of benzo(a)pyrene on a number of days during colder weather. We expected this because:
- wood heaters are used more during winter
- PAHs from diesel engines and other combustion sources form more readily when the ambient temperature is low
- there is generally less dispersion of pollutants in winter, due to lower winds.
Two formaldehyde samples taken on 16 August and 19 August 2005 (at 26 and 28 ppb respectively) were higher than others reported. Although the concentrations on these two days were approximately 10 times the average concentration, all reported concentrations remained well below the monitoring investigation level. Investigations have not identified the source of these reported levels.
24-hour results
| Sample date |
Benzene (ppb) |
Benzo(a)pyrene (ng/m3) |
Formaldehyde (ppb) |
Toluene (ppb) |
Xylene (ppb) |
| Annual investigation level |
3.0 |
0.3 |
Not applicable |
100.0 |
200.0 |
| 24 hour investigation level |
Not applicable |
Not applicable |
40.0 |
1000.0 |
250.0 |
| |
|
|
|
|
|
| Annual average |
0.5 |
0.2 |
Not applicable |
1.8 |
0.7 |
| Maximum 24 hour level |
Not applicable |
Not applicable |
28.4 |
4.9 |
2.0 |
| |
|
|
|
|
|
| 27-May-05 |
Not detected |
Not detected |
2.8 |
0.4 |
0.2 |
| 30-May-05 |
0.9 |
0.8 |
3.3 |
3.1 |
0.9 |
| 02-Jun-05 |
0.7 |
Not detected |
7.0 |
4.9 |
1.2 |
| 05-Jun-05 |
1.4 |
2.6 |
4.8 |
4.8 |
1.4 |
| 08-Jun-05 |
1.1 |
Not detected |
5.7 |
4.5 |
1.7 |
| 11-Jun-05 |
0.3 |
Not detected |
7.6 |
2.7 |
1.9 |
| 14-Jun-05 |
Not detected |
Not available |
1.6 |
2.3 |
1.1 |
| 17-Jun-05 |
0.3 |
Not detected |
0.5 |
3.7 |
1.3 |
| 20-Jun-05 |
Not detected |
Not detected |
0.6 |
2.6 |
0.9 |
| 23-Jun-05 |
0.8 |
0.6 |
1.2 |
3.7 |
1.4 |
| 26-Jun-05 |
1.7 |
1.9 |
2.5 |
4.2 |
1.7 |
| 29-Jun-05 |
1.4 |
0.6 |
1.9 |
4.9 |
2.0 |
| 02-Jul-05 |
0.8 |
0.3 |
1.8 |
3.9 |
1.4 |
| 05-Jul-05 |
Not detected |
Not detected |
0.7 |
1.9 |
0.6 |
| 08-Jul-05 |
1.0 |
0.5 |
2.4 |
4.1 |
1.5 |
| 11-Jul-05 |
1.5 |
1.0 |
2.4 |
4.2 |
1.6 |
| 14-Jul-05 |
0.8 |
0.6 |
0.4 |
4.1 |
1.2 |
| 17-Jul-05 |
0.3 |
Not detected |
0.7 |
2.3 |
0.7 |
| 20-Jul-05 |
1.3 |
0.8 |
1.6 |
4.5 |
1.8 |
| 23-Jul-05 |
Not detected |
Not detected |
Not sampled |
2.4 |
0.6 |
| 26-Jul-05 |
0.3 |
Not detected |
0.4 |
1.9 |
0.6 |
| 29-Jul-05 |
Not detected |
Not detected |
0.5 |
2.2 |
0.6 |
| 01-Aug-05 |
1.3 |
0.7 |
Not detected |
4.3 |
1.8 |
| 04-Aug-05 |
0.5 |
Not detected |
1.5 |
2.3 |
0.8 |
| 07-Aug-05 |
0.3 |
0.3 |
Not sampled |
2.2 |
0.6 |
| 10-Aug-05 |
0.3 |
Not detected |
Not detected |
1.9 |
0.7 |
| 13-Aug-05 |
0.5 |
Not detected |
1.0 |
2.9 |
0.9 |
| 16-Aug-05 |
0.3 |
Not detected |
26.2 |
1.8 |
0.5 |
| 19-Aug-05 |
Not detected |
Not detected |
28.4 |
1.5 |
0.4 |
| 22-Aug-05 |
0.3 |
Not detected |
1.2 |
1.4 |
0.4 |
| 25-Aug-05 |
0.9 |
Not detected |
Not detected |
3.1 |
0.9 |
| 28-Aug-05 |
0.5 |
Not detected |
0.7 |
2.2 |
0.6 |
| 31-Aug-05 |
Not detected |
0.2 |
Not detected |
1.1 |
0.2 |
| 03-Sep-05 |
0.7 |
Not sampled |
1.2 |
2.7 |
0.8 |
| 06-Sep-05 |
Not sampled |
Not detected |
1.1 |
Not sampled |
Not sampled |
| 09-Sep-05 |
Not detected |
Not detected |
1.1 |
1.3 |
0.3 |
| 04-Dec-05 |
0.3 |
Not detected |
1.2 |
0.6 |
0.3 |
| 07-Dec-05 |
0.3 |
Not detected |
0.8 |
0.6 |
0.2 |
| 10-Dec-05 |
Not detected |
Not detected |
0.9 |
0.6 |
0.2 |
| 13-Dec-05 |
0.3 |
Not detected |
1.0 |
0.7 |
0.2 |
| 16-Dec-05 |
0.3 |
Not detected |
Not detected |
0.7 |
0.2 |
| 19-Dec-05 |
0.3 |
Not detected |
Not detected |
0.7 |
0.2 |
| 22-Dec-05 |
0.5 |
Not detected |
1.0 |
1.3 |
0.3 |
| 25-Dec-05 |
Not detected |
Not detected |
Not detected |
0.3 |
Not detected |
| 28-Dec-05 |
Not detected |
Not detected |
1.0 |
Not detected |
Not detected |
| 31-Dec-05 |
0.4 |
Not detected |
2.4 |
0.9 |
0.5 |
| 03-Jan-05 |
Not detected |
Not detected |
0.8 |
0.3 |
0.2 |
| 06-Jan-05 |
Not detected |
Not detected |
1.1 |
0.4 |
0.2 |
| 09-Jan-05 |
0.3 |
Not detected |
2.5 |
0.7 |
0.3 |
| 12-Jan-05 |
Not detected |
Not detected |
1.5 |
0.6 |
0.3 |
| 15-Jan-05 |
Not detected |
Not detected |
1.1 |
0.3 |
0.2 |
| 18-Jan-05 |
Not detected |
Not detected |
1.5 |
0.4 |
0.2 |
| 21-Jan-05 |
Not detected |
Not detected |
2.8 |
0.5 |
0.2 |
| 24-Jan-05 |
Not detected |
Not detected |
0.8 |
0.3 |
Not detected |
| 27-Jan-05 |
0.6 |
Not detected |
3.0 |
1.2 |
0.5 |
| 30-Jan-05 |
Not detected |
Not detected |
1.0 |
0.4 |
0.2 |
| 02-Feb-05 |
Not detected |
Not detected |
Not available |
0.3 |
Not detected |
| 05-Feb-05 |
Not detected |
Not detected |
1.1 |
0.3 |
Not detected |
| 08-Feb-05 |
Not detected |
Not detected |
1.4 |
0.6 |
0.3 |
| 11-Feb-05 |
Not detected |
Not detected |
0.7 |
0.5 |
0.3 |
| 14-Feb-05 |
0.3 |
Not detected |
0.8 |
0.7 |
0.4 |
| 17-Feb-05 |
0.3 |
Not detected |
1.9 |
1.2 |
0.7 |
| 20-Feb-05 |
Not detected |
Not detected |
0.7 |
0.6 |
0.4 |
| 23-Feb-05 |
0.3 |
Not detected |
2.5 |
0.9 |
0.5 |
| 26-Feb-05 |
Not detected |
Not detected |
0.7 |
0.4 |
0.2 |
| 01-Mar-05 |
0.4 |
Not detected |
1.0 |
1.2 |
0.6 |
Not applicable: A 24-hour investigation level is not specified for benzene and benzo(a)pyrene.
Not detected: Air toxic was below measurable levels.
Not sampled: No result is available due to sampling failure or error.
ppb: parts per billion (for every one billion litres of air there is one litre of the pollutant).
ng/m3: nanograms per cubic metre (1 billionth of a gram per cubic metre).
Detection limits are as follows:
| Compound |
Benzene (ppb) |
Benzo(a)pyrene (ng/m3) |
Formaldehyde (ppb) |
Toluene (ppb) |
Xylene (ppb) |
| Detection limit |
0.3 |
0.2 |
0.1 |
0.2 |
0.2 |
ppb: parts per billion (for every one billion litres of air there is one litre of the pollutant).
ng/m3: nanograms per cubic metre (1 billionth of a gram per cubic metre).