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Polycyclic aromatic hydrocarbons in the latrobe valley
an%6981 ml s3.m + 0.00 g. 1988 Pcrgllmon Press plc
~tmospberfc EnnDironme~ Vol. 22. No. 1 I, pp. 2549 25%. 1988. Printed in Gnat
B&k.
POLYCYCLIC
AROMATIC HYDROCARBONS LATROBE VALLEY
IN THE
R. J. LYALL and M. A. HOPPER Gippsland Institute of Advanced Education, Switchback Road, Churchill, Victoria, Australia, 3840
and S. J.
MAINWARING
University of Melbourne, Grattan Street, Parkville, Victoria, Australia, 3052 (Firsf
received
3 1 Auyus~1987 and infinalform
2 May
1988)
Abatrac&-Atmospheric concentrations of eight polycyciic aromatic hydrocarbons (PAHs) were determined from 24-h particulate samples collected at five urban and rural locations in the Latrobe Valley over two 12 month periods. Samples were collected on glass fibre filters using high volume air samplers and then extracted with cyclohexane. The components were separated and analysed using high petiormance liquid chromatography with fluorescencedetection. The results were examined and compared with meteorological data to ascertain the overall levels of pollution by these compounds and to try and identify their origins. It was found that concentrations varied considerably from day to day but were much greater during the winter months. Average levels at the urban sites were lessthan have been found in industrial cities elsewhere but considerably higher thitn in rural areas. The results indicated that the main contributor to contamination was the motor vehicle, with domestic healing adding a significant contribution during the colder weather. There was evidence of industrial pollution on certain days and some tentative suggestionsas to the origins of this have been made. Key wnrd index: Fluorescence, high performance liquid chromatography. Latrobe Valley. polycyclic aromatic hydrocar~ns
lNTRODUCTlON
Polycyclic aromatic
hydrocarbons
tous con~~minants
of the environment
(PAHs)
are ubiquihaving been
in urban, rural and remote areas of the world and as some have been shown to have carcinogenic and/or mutagenic properties (Griciute, 1978) their presence is of considerable concern. Most PAHs exist in the ambient air absorbed on particulate matter (Yamasaki et ai., 1982) and are formed mainly by anthropogenic processes (Guerin, 5978) caused by the combustion of organic fuels. Extensive brown coal deposits are located in the I&robe Valley and it is for this reason that it is the site for the main electricity generating stations for the found
State of Victoria
and several other plants
which use
coal as a fuel or as a feedstock for combustion processes. Therefore the potential for the generation of PAHs in the area and their subsequent release to the environment is considerable. To determine whether or not the levels of PAHs in the Latrobe Valley were a matter for concern, the spatial and temporal dist~bution of selected PAHs was determined. The PAHs studied were pyrene (PYRX benz(a)pyrene (BaP), benz(e)pyrene (BeP), benz(k)fluoranthene (BkF), perylene (PER), benz(ghi)
perylene (BghiP), anthanthrene (ANT) and coronene (COR). These were then compared with levels in other areas and in other studies to ascertain the degree of any concern. The ratio of BaP to COR, which gives an indication of the type of activity responsible for the generation of the PAHs (Blokzijl and Guicherit, 1972) was examined, and the variations in daily levels were compared with wind speed and direction to try to identify the sources of pollution. A map of the central Latrobe Valley showing the sampling sites and main potential sources of PAHs is shown in Fig. 1. ’ Five sites were chosen for the major (12 monthly) sampling program. Three of the sites were in the main, similar, urban centres of Moe, Morweil and Traralgon. The Morwell site was in the centre of the industrial area whereas Moe and Traralgon were on the fringes. Newborough was chosen as it was directly west of the most westerly power station and Thorns Bridge was in a rural area several kilometers from the urban and industrial sources. Samples were taken at Morwell and New~rough for one year from July 1980 to June f 98 1 and at Moe, Traralgon and Thorns Bridge from January to December 1982.
2549
2550
..**.* *..*.* . ...*. .*.*** . . ...* .. ... .
LEG END
e
open
C”t
Hines
Fig. 1. The central Latrobe Valley.
EXPERIMENTAL
Particulate samples were collected on 203 x 245mm Gclman type A fibnglass filters using Cairns or Extech high volume air samplers. These samplers were placed in elevated positions above any buildings or structures in the immediate area. At Newborough this was above the roof of a two storey building approximately IOm above ground level, and at the other sites about 4m above the ground at the air monitoring stations operated by the Environmental Protection Authority of Victoria. Samples were taken every 6th day, for about 24-h, beginning and ending around midnight. The sampling rate was set at approximately 70m3 h- ’ giving a total calibrated sample volume of 14&I-1900m3. The exposed filters were folded and allowed to normalize for 24-h in the laboratory before being weighed and extracted. Extraction und concentration The exposed filter papers were loosely rolled, placed in a Wml soxhlet extractor and extracted with 90 ml of Ajax Unichrom grade cyclohexane for 12-h at a rate of 20 cycles h-‘. The extract was cooled and concentrated to l-2mI under vacuum on a rotary evaporator at 40°C. The concentrate was then transferred quantitatively to a 5 ml veeshaped minivial and placed under a stream of filtered research grade N,. The flask was washed several times with small amounts of cydohexane and the washings added to the minivial. The concentrate and washings were evaporated to
dryness under N, without the application of heat, the vials being removed from the nitrogen stream as soon as they were dry to mmimize any loss of the dried PAH by evaporation. Exactly LOml of HPLC grade methanol was addnd to the vial which was placed in an ultrasonic bath at 40°C for at least 15min to aid solvation of the organic material. The extracts were then refrigerated. Anaiysis The anafysis was carried out using High Performance Liquid Chromatography (HPLC) with fluorescence detection. The system used consisted of an Altex model 100 dual piston pump, a stop Row valve, an Altex syringe loading loop injector, a 250 mm Ultrasphere ODS column and a Perkin Elmer 204A dual optical grating spectrophotometer fitted with an 8pl flow-through cell. The methanoiic extracts were allowed to come to room temperature, filtered through an 0.4s~ Teflon fiiter and SO-75 d of filteted extract injected through a 1OOfi loop. Two chromatographic etutions were necessaryto separate the eight PAHs as several eluted very close togetkr and bad to be separated by careful selection of fluomscenoe oooditions. Firstly, 10 % water in metbaool at a flow rate of20ml mine ’ was used as the mob& phase to separate PYR, BeP. BaP, BghiP, ANT and COR in that order. The aeeond chromatograph was run using neat methanol at LOmf mint and BkF and PER were determined. Tbe fluoresance wavelength conditions were as in Tabk 1 and typical chrotnatographs are shown in Fig. 2.
Polycyclic aromatic hydrocarbons in Latrobe Valley Table 1. Chromato~aphic
Mobile phase Retention vol. (ml) Excitation w.k (om) Emission w.1. (nm) Detection limits (ngml-‘) (ng m-‘)
PYR
BeP
BaP
I 10
16
327
327
362
388
388
405
2 0.001
6 0.004
2SSl
conditions ANT
COR
10% water in methanol 34 17 25
50
378
299
299
404
404
415
444
444
435
435
5 0.003
7 0.004
O.&f8
0.Z
BghiP
BkF
PER
ImetItan 1 8.0 7.5
0.2 0.0001
Mobile Phese 109Gwatt in methanol 8t 2.0 mVmin
COR
I
1
S
10
15
20
Elution Time (mind
Mobile Phavs neatmethanolat 1.0 ml/min PER
Elution Time (mind
Fig. 2. Typical Chromatography
25
2552
R. J.
LVAl
At regular times the stop-flow technique was used to determine spectra of the eluted components in order to check the efEciency of the separation. In all cases this proved satisfactory. The concentrations of the components was determined by comparing peak heights with standard mixtures eluted under the same conditions. The efficiency of the extraction and accuracy of the method were determined by anaiysing filter papers spiked with known amounts of PA% and with an NBS Standard Urban Dusts/Organics sample. With the spiked sample recovery was better than 95 % and results for the dust sample were within the limits of the certified results. RESULTS
The annual ranges, mean and standard deviation values for all PAWS studied are in Table 2. Graphs comparing the rolling quarterly averages for COR and BaP are shown in Fig. 3. Rolling quarterly averages were used instead of straight monthly averages to smooth the effects of large monthly standard deviations caused by the high daily variations and small number of samples taken in any month. DISCUSSlON
As can be seen from Table 2 there was a large variation in day to day concentrations of all PAHs resutting in high standard deviations, which often exceeded the mean values. Large seasonal variations can be seen from the graphs of rolling quarterly averages in Fig.3. Low levels of PAHs occurred during the summer months and high levels during winter. This variation has been
I_ CI u/
noted in other studies and is considered to be mainly due to a combination of the higher usage of domestic and commercial heating installations during the colder seasons and the increased removal of PAHs from the atmosphere by photochemical oxidation during the hotter months (Blokzijl and Guicherit, 1972). The magnitude of the levels at the various sites accurately reflect, for the most part, the density of the vehicular activity and the residential area in the vicinity of the sampling site. As can be seen from the graphs in Fig. 3, the highest values were obtained at the urban sites of Morwell East, Moe and Traralgon, whereas the lowest values occurred at the rural site at Thorns Bridge. The sampler at Newborough was in a semi-rural setting on the fringes of a residential area and with the large Yallourn power stations close by to the east. This site generally recorded levels between the rural and urban sites. A comparison of daily concentrations with wind direction at Newborough indicated only that the coal fired power stations at Yallourn had little effect on PAH levels in the immediate area, as these did not increase when the wind was from the east, which was the direction of the power stations. This was in agreement with findings from other studies (Guerin, 1978; Hangebrauk et al., 1967), that large scale power plants contributed little to the atmospheric PAH con~ntrations. The evidence from Thorns Bridge was similar, and the lower levels at this site indicated that the main sources appeared to be located in the urban areas, and that the pollutants were transported only to a small degree.
Table 2. Ranges and mean values of PAH concentrations (all values in ng m-j)
Thorns PYR BeP BaP
Range Mean s.d. Range Mean s.d. Range Mean s.d.
BghiP ANT COR BkF PER
Range Mean s.d. Range Mean s.d. Range Mean s.d. Range Mean s.d. Range Mean s.d.
Morwell
Newborough
0.~.75 0.087 0.117 0.004-l .4 0.35 0.44 0.003-1s 0.16 0.31 0.011-2.8 0.53 0.71 0.004-l .7 0.21 0.34 0.010-1.1 0.27 0.3 I 0.003-0.67 0.099 0.113 0.002-0.2 0.035 0.058
o.oo6-o.34 0.06 0.06 O.OOti.56 0. I21 0.141 0.002-0.46 0.056 0.093 0.006-f.13 0.205 0.230 0.00-2.96 0.134 0.446 0.003-1.47 0.152 0.262 o.00Lo.25 0.035 0.057 O.CO1-@072 0.014 0.019
Moe 0.~8~.42 0.072 0.086 0.01&1.61 0.26 0.35 0.006-l .48 0.20 0.36 0.027-2.30 0.46 0.60 0.00&0.94 0.127 0.191 0.02~.89 0.172 0.199 0.005-0.85 0.104 0.175 0.001-0.127 0.021 0.035
Traralgon
Bridge
0.02 l-O.66 0.15
0.0104.15 0.04 I
0.16
0.030 0.007-0.26 0.064 0.060 0.002-O.1f 5 0.033 0.038 0.005-0.40 0.104 0.104 0.004-Q.159 0.034 0.039 0.005-0.23 0.052 0.052 0.002-0.088 0.020 0.02 1 0.001-0.026 0.005 0.006
0.038-2.34 0.36 0.50
0.011-I .78 0.26
0.42 0.058-4.65 0.67 0.91 0.01S-3.32 0.26 0.57 0.038-2.3 0.35 0.46 0.013-0.81 0.13 0.20 0.00-0.24 0.032 0.053
2553
Polycyclic aromatic hydrocarbons in Latrobe Valley
1.0
.9
.9
.7
4
2
.A
.:
.:
J
F
M
A
M
J
J
A
S
0
N
D
S
0
N
D
mid month of quarter
BaP .9
4
.7
*a 3
4
4
.2
J
F
M
A
Y
J
J
A
mid month of quarter
Fig. 3. Rolling quarterly averages of some PAHs.
Although not recorded here, the particulate loading in the atmosphere was measured, and it was found that there was no correlation or pattern evident between these results and the PAH levels. This data is in agreement with observations made by Mainwaring and Stirling (1981) that PAHs are associated mainly with the smaller diameter aerosols which have correspondingly less effect on the total weight of solid material in the atmosphere. Results of some other studies on atmospheric
PAH concentrations in Australia, Europe, Asia and America are shown in Table3. The levels in Europe. and Asia are, in most cases, at least an order of magnitude above any found in this study. This is probably due to the higher population density and greater use of solid fuels for heating and cooking in these areas. The winter averages for BaP in the towns of Moe and Traralgon were only a little lower than has been found in Melbourne, Ontario and Los Angeles, which
2554
R. J. LVALL rr uf. Table 3. Some PAH levels from other studies
Location
Year
Season
London. U.K. Antony, France
1972:3 1979 1980 1979 1980
All Yr Summer Winter Summer Winter All Yr Summer Winter All Yr Summer Autumn Winwr Spring Winter
St. Denis, France Nuremberg F.R.G. T&wan. lran
19X1
Los Angeles, U.S.A. Los Angeles. U.S.A.
lY71.:2 1974
Melbourne. Australia
1979
1981
BaP (ngm J1
(ngm -‘I
5 IO 0.02 4.h 0.07
3 19 0.14 I .x4 ox?
15.0
3.3
3.47
COR
are cities 100 times larger. This indicates that the nonvehicular PAH pollution at these town sites during winter, is above the level which may be expected in a provincial township. The COR averages at the urban locations were less than 25-50% of the levels recorded in Melbourne and Los Angeles and probably accurately reflect the respective traffic densities. The comparison between the rural site in Los Angeles County and Thorns Bridge is interesting. The yearly average of BaP is nearty identical, while the COR level is 4 times higher at the American site. This indicates that the impact of domestic emissions are similar but that the vehicular traffic is more intense in Los Angeles County. As previously reported, the levels of BaP and COR can be a guide to the origins of the PAW contamination, COR coming mainly from motor vehicle exhausts and BaP from domestic and industrial sources (Kommers, 1976). Blokzijl and Guicherit (1972) have reported that a ratio of BaP to COR of less than 1.0 is indicative of automobile sources, and of greater than 1.7 is indicative of domestic heating sources. For 90 % of the days sampled, this ratio was below 1.0 and on only two occasions did it rise above 1.7.This indicates that the major source of the PAH pollution in this area was due to the automobile. At Morweil East, Moe and Traralgon however, there was a general increase in the BaP/COR ratio in the colder months, which indicated that there was a significant contribution from domestic type sources, although this was still less than that from the automobile. This effect was expected as domestic and commercial heating units would be used to a much greater degree during winter. There were several times during the year when certain PAHs, and in particular BaP, rose to levels which did not fit the general pattern and a comparison of these was made with meteorological data. BaP levels increased at Morwell East on several days when the winds were light and from the southerly quadrant. The relatively high BaP/COR ratio indicated that the
Reference .--
City Residential
Commins and Hampton, 1976. Muel and Saguem. 198s.
Industrial
Muel and Saguem. 1985.
2.5
Urban Urban
Stemmetzer et al., 1984. Aghdaie and Abid. 1986.
0.20 1.13 I.66 4.44 2.49 2.05
Rural Urban
Gordon and Bryan, 1973. Gordon, 1976.
Urban
Mainwaring and Stirling, 1981.
127 X.2Y 0.03 0.17 0.X I.?? 0.77 0.99
Comments
PAH concentration was not due to vehicular sources, and as the daily temperatures were comparatively mild, it was unlikely to be caused by an increase in heating activity. Therefore the rise in BaP levels was probably due to industrial sources. The possible industrial sources of PAH pollution to the south of Morwell were the power stations and the char plant, and considering evidence from this and other studies the source was probably not the power stations. Therefore the most likely source of the atmospheric PAHs on these days was the char plant. At Moe and Traralgon there were several days of high BaP concentration, and on all these days except one, the winds were variable or had a westerly component. As both sites have extensive residential areas in that direction it is probable that the extra BaP levels were due to domestic heating sources. Very low temperatures were recorded in the morning on several of these days, which would lead to an increase in domestic and commercial heating activity. On some of these days there was also a small increase in levels at Thorns Bridge, probably due to a limited transport of the particulate matter from residential areas. increased
REFERENCES Aghdaie N. and Abid S. (1986) Determination of some airborne polycyclic aromatic hydrocarbons in the Tehran atmosphere. Proc. 7th World Clean Air Congress5,68-75. Blokzijl P. J. and Guicherit R. (1972) The occurrence of polynuclear aromatic hydrocarbons (PAH) in outdoor air.
Th’O-Nieuws 27,6X3-660.
Hampton L. (1976) Changing pattern in concentrations of polycycticaromatic hyd&s in the air of Central London. Atmosp~ic EnolnmAleAt I@,
Commins B. T. and
561-562. Gordon R. J. (1976) Distribution of airborne polycyclic aromatic hydrocarbons throughout Los An&es. En&. Sci. Technol. 10,370-373. Gordon R. J. and Bryan R. J. (1973) Patterns in airborne polynuclear aromatic hydrocarborr titration at four Los Angeles sites. Envir. Sei. Technoi. 7, 10504051.
Polycyclic aromatic hydrocarbons in Latrobe Valley Griciutc
L. (1978) Environmental Carcinogens-Sefected Methods of Analysis, 3, Inter. Agency for Research on
Cancer, 3-8. Guerin M, (1978) Energy sources of polycyclic aromatic hydrocarbons. Polycyclic Hydrocarbons and Cancer, 1, Enaironment, Chemistry and Metabolism (edited by H. V. Gelboin and P.O.P.Ts’o), pp. 342. Academic Press, New York. Hangebrauk R. P., von Lehmden D. J. and Meeker J. E. (1967) Sources of Polynuclear Aromatic Hydrocarbons in ;he aimosphere. Env~onmental Health Se&s, U. S. Dept of Health, Public Health Service Publication No. 999-AP33, 9-12. Kommers F. J. W. (1976) Determination of Polycyclic Hydrocarbons in air.1 IG =TNO Research Institute for En-
2555
vironmental Hygiene, Report G 689, pp. l-14. Mainwarina S. J. and Stirlinn D. M. (1981) A Studv of the site dist~but~n and ~n~nt~tions bf poiynucle& aromatic hydrocarbons in melbourne air. i%c. 7th hemat. Clean Air Conf pp. 605-622. Ann Arbor Science. Mucl B. and Saguem S. (1985) Determination of 23 polycyclic aromatic hydrocarbons in atmospheric particulate matter of the Paris area. ht. J. Enoir. Analyl. Chem. 11I-131. Steinmetzer H. C., Baumeister W. and Vierle 0. (1984) Analytical investigation on the contents of polycyclic aromatic hydrocarbons in airborne particulate matter from two Bavarian cities. Sci. total Enuir. 36, 91-96. Yamasaki H., Kuwata K. and Miuamoto H. (1982) Effects of ambient temperature on aspects of airborne polycyclic aromatic hydrocarbons. Entiir Sci. Technol. 16, 189-194.
~tmospberfc EnnDironme~ Vol. 22. No. 1 I, pp. 2549 25%. 1988. Printed in Gnat
B&k.
POLYCYCLIC
AROMATIC HYDROCARBONS LATROBE VALLEY
IN THE
R. J. LYALL and M. A. HOPPER Gippsland Institute of Advanced Education, Switchback Road, Churchill, Victoria, Australia, 3840
and S. J.
MAINWARING
University of Melbourne, Grattan Street, Parkville, Victoria, Australia, 3052 (Firsf
received
3 1 Auyus~1987 and infinalform
2 May
1988)
Abatrac&-Atmospheric concentrations of eight polycyciic aromatic hydrocarbons (PAHs) were determined from 24-h particulate samples collected at five urban and rural locations in the Latrobe Valley over two 12 month periods. Samples were collected on glass fibre filters using high volume air samplers and then extracted with cyclohexane. The components were separated and analysed using high petiormance liquid chromatography with fluorescencedetection. The results were examined and compared with meteorological data to ascertain the overall levels of pollution by these compounds and to try and identify their origins. It was found that concentrations varied considerably from day to day but were much greater during the winter months. Average levels at the urban sites were lessthan have been found in industrial cities elsewhere but considerably higher thitn in rural areas. The results indicated that the main contributor to contamination was the motor vehicle, with domestic healing adding a significant contribution during the colder weather. There was evidence of industrial pollution on certain days and some tentative suggestionsas to the origins of this have been made. Key wnrd index: Fluorescence, high performance liquid chromatography. Latrobe Valley. polycyclic aromatic hydrocar~ns
lNTRODUCTlON
Polycyclic aromatic
hydrocarbons
tous con~~minants
of the environment
(PAHs)
are ubiquihaving been
in urban, rural and remote areas of the world and as some have been shown to have carcinogenic and/or mutagenic properties (Griciute, 1978) their presence is of considerable concern. Most PAHs exist in the ambient air absorbed on particulate matter (Yamasaki et ai., 1982) and are formed mainly by anthropogenic processes (Guerin, 5978) caused by the combustion of organic fuels. Extensive brown coal deposits are located in the I&robe Valley and it is for this reason that it is the site for the main electricity generating stations for the found
State of Victoria
and several other plants
which use
coal as a fuel or as a feedstock for combustion processes. Therefore the potential for the generation of PAHs in the area and their subsequent release to the environment is considerable. To determine whether or not the levels of PAHs in the Latrobe Valley were a matter for concern, the spatial and temporal dist~bution of selected PAHs was determined. The PAHs studied were pyrene (PYRX benz(a)pyrene (BaP), benz(e)pyrene (BeP), benz(k)fluoranthene (BkF), perylene (PER), benz(ghi)
perylene (BghiP), anthanthrene (ANT) and coronene (COR). These were then compared with levels in other areas and in other studies to ascertain the degree of any concern. The ratio of BaP to COR, which gives an indication of the type of activity responsible for the generation of the PAHs (Blokzijl and Guicherit, 1972) was examined, and the variations in daily levels were compared with wind speed and direction to try to identify the sources of pollution. A map of the central Latrobe Valley showing the sampling sites and main potential sources of PAHs is shown in Fig. 1. ’ Five sites were chosen for the major (12 monthly) sampling program. Three of the sites were in the main, similar, urban centres of Moe, Morweil and Traralgon. The Morwell site was in the centre of the industrial area whereas Moe and Traralgon were on the fringes. Newborough was chosen as it was directly west of the most westerly power station and Thorns Bridge was in a rural area several kilometers from the urban and industrial sources. Samples were taken at Morwell and New~rough for one year from July 1980 to June f 98 1 and at Moe, Traralgon and Thorns Bridge from January to December 1982.
2549
2550
..**.* *..*.* . ...*. .*.*** . . ...* .. ... .
LEG END
e
open
C”t
Hines
Fig. 1. The central Latrobe Valley.
EXPERIMENTAL
Particulate samples were collected on 203 x 245mm Gclman type A fibnglass filters using Cairns or Extech high volume air samplers. These samplers were placed in elevated positions above any buildings or structures in the immediate area. At Newborough this was above the roof of a two storey building approximately IOm above ground level, and at the other sites about 4m above the ground at the air monitoring stations operated by the Environmental Protection Authority of Victoria. Samples were taken every 6th day, for about 24-h, beginning and ending around midnight. The sampling rate was set at approximately 70m3 h- ’ giving a total calibrated sample volume of 14&I-1900m3. The exposed filters were folded and allowed to normalize for 24-h in the laboratory before being weighed and extracted. Extraction und concentration The exposed filter papers were loosely rolled, placed in a Wml soxhlet extractor and extracted with 90 ml of Ajax Unichrom grade cyclohexane for 12-h at a rate of 20 cycles h-‘. The extract was cooled and concentrated to l-2mI under vacuum on a rotary evaporator at 40°C. The concentrate was then transferred quantitatively to a 5 ml veeshaped minivial and placed under a stream of filtered research grade N,. The flask was washed several times with small amounts of cydohexane and the washings added to the minivial. The concentrate and washings were evaporated to
dryness under N, without the application of heat, the vials being removed from the nitrogen stream as soon as they were dry to mmimize any loss of the dried PAH by evaporation. Exactly LOml of HPLC grade methanol was addnd to the vial which was placed in an ultrasonic bath at 40°C for at least 15min to aid solvation of the organic material. The extracts were then refrigerated. Anaiysis The anafysis was carried out using High Performance Liquid Chromatography (HPLC) with fluorescence detection. The system used consisted of an Altex model 100 dual piston pump, a stop Row valve, an Altex syringe loading loop injector, a 250 mm Ultrasphere ODS column and a Perkin Elmer 204A dual optical grating spectrophotometer fitted with an 8pl flow-through cell. The methanoiic extracts were allowed to come to room temperature, filtered through an 0.4s~ Teflon fiiter and SO-75 d of filteted extract injected through a 1OOfi loop. Two chromatographic etutions were necessaryto separate the eight PAHs as several eluted very close togetkr and bad to be separated by careful selection of fluomscenoe oooditions. Firstly, 10 % water in metbaool at a flow rate of20ml mine ’ was used as the mob& phase to separate PYR, BeP. BaP, BghiP, ANT and COR in that order. The aeeond chromatograph was run using neat methanol at LOmf mint and BkF and PER were determined. Tbe fluoresance wavelength conditions were as in Tabk 1 and typical chrotnatographs are shown in Fig. 2.
Polycyclic aromatic hydrocarbons in Latrobe Valley Table 1. Chromato~aphic
Mobile phase Retention vol. (ml) Excitation w.k (om) Emission w.1. (nm) Detection limits (ngml-‘) (ng m-‘)
PYR
BeP
BaP
I 10
16
327
327
362
388
388
405
2 0.001
6 0.004
2SSl
conditions ANT
COR
10% water in methanol 34 17 25
50
378
299
299
404
404
415
444
444
435
435
5 0.003
7 0.004
O.&f8
0.Z
BghiP
BkF
PER
ImetItan 1 8.0 7.5
0.2 0.0001
Mobile Phese 109Gwatt in methanol 8t 2.0 mVmin
COR
I
1
S
10
15
20
Elution Time (mind
Mobile Phavs neatmethanolat 1.0 ml/min PER
Elution Time (mind
Fig. 2. Typical Chromatography
25
2552
R. J.
LVAl
At regular times the stop-flow technique was used to determine spectra of the eluted components in order to check the efEciency of the separation. In all cases this proved satisfactory. The concentrations of the components was determined by comparing peak heights with standard mixtures eluted under the same conditions. The efficiency of the extraction and accuracy of the method were determined by anaiysing filter papers spiked with known amounts of PA% and with an NBS Standard Urban Dusts/Organics sample. With the spiked sample recovery was better than 95 % and results for the dust sample were within the limits of the certified results. RESULTS
The annual ranges, mean and standard deviation values for all PAWS studied are in Table 2. Graphs comparing the rolling quarterly averages for COR and BaP are shown in Fig. 3. Rolling quarterly averages were used instead of straight monthly averages to smooth the effects of large monthly standard deviations caused by the high daily variations and small number of samples taken in any month. DISCUSSlON
As can be seen from Table 2 there was a large variation in day to day concentrations of all PAHs resutting in high standard deviations, which often exceeded the mean values. Large seasonal variations can be seen from the graphs of rolling quarterly averages in Fig.3. Low levels of PAHs occurred during the summer months and high levels during winter. This variation has been
I_ CI u/
noted in other studies and is considered to be mainly due to a combination of the higher usage of domestic and commercial heating installations during the colder seasons and the increased removal of PAHs from the atmosphere by photochemical oxidation during the hotter months (Blokzijl and Guicherit, 1972). The magnitude of the levels at the various sites accurately reflect, for the most part, the density of the vehicular activity and the residential area in the vicinity of the sampling site. As can be seen from the graphs in Fig. 3, the highest values were obtained at the urban sites of Morwell East, Moe and Traralgon, whereas the lowest values occurred at the rural site at Thorns Bridge. The sampler at Newborough was in a semi-rural setting on the fringes of a residential area and with the large Yallourn power stations close by to the east. This site generally recorded levels between the rural and urban sites. A comparison of daily concentrations with wind direction at Newborough indicated only that the coal fired power stations at Yallourn had little effect on PAH levels in the immediate area, as these did not increase when the wind was from the east, which was the direction of the power stations. This was in agreement with findings from other studies (Guerin, 1978; Hangebrauk et al., 1967), that large scale power plants contributed little to the atmospheric PAH con~ntrations. The evidence from Thorns Bridge was similar, and the lower levels at this site indicated that the main sources appeared to be located in the urban areas, and that the pollutants were transported only to a small degree.
Table 2. Ranges and mean values of PAH concentrations (all values in ng m-j)
Thorns PYR BeP BaP
Range Mean s.d. Range Mean s.d. Range Mean s.d.
BghiP ANT COR BkF PER
Range Mean s.d. Range Mean s.d. Range Mean s.d. Range Mean s.d. Range Mean s.d.
Morwell
Newborough
0.~.75 0.087 0.117 0.004-l .4 0.35 0.44 0.003-1s 0.16 0.31 0.011-2.8 0.53 0.71 0.004-l .7 0.21 0.34 0.010-1.1 0.27 0.3 I 0.003-0.67 0.099 0.113 0.002-0.2 0.035 0.058
o.oo6-o.34 0.06 0.06 O.OOti.56 0. I21 0.141 0.002-0.46 0.056 0.093 0.006-f.13 0.205 0.230 0.00-2.96 0.134 0.446 0.003-1.47 0.152 0.262 o.00Lo.25 0.035 0.057 O.CO1-@072 0.014 0.019
Moe 0.~8~.42 0.072 0.086 0.01&1.61 0.26 0.35 0.006-l .48 0.20 0.36 0.027-2.30 0.46 0.60 0.00&0.94 0.127 0.191 0.02~.89 0.172 0.199 0.005-0.85 0.104 0.175 0.001-0.127 0.021 0.035
Traralgon
Bridge
0.02 l-O.66 0.15
0.0104.15 0.04 I
0.16
0.030 0.007-0.26 0.064 0.060 0.002-O.1f 5 0.033 0.038 0.005-0.40 0.104 0.104 0.004-Q.159 0.034 0.039 0.005-0.23 0.052 0.052 0.002-0.088 0.020 0.02 1 0.001-0.026 0.005 0.006
0.038-2.34 0.36 0.50
0.011-I .78 0.26
0.42 0.058-4.65 0.67 0.91 0.01S-3.32 0.26 0.57 0.038-2.3 0.35 0.46 0.013-0.81 0.13 0.20 0.00-0.24 0.032 0.053
2553
Polycyclic aromatic hydrocarbons in Latrobe Valley
1.0
.9
.9
.7
4
2
.A
.:
.:
J
F
M
A
M
J
J
A
S
0
N
D
S
0
N
D
mid month of quarter
BaP .9
4
.7
*a 3
4
4
.2
J
F
M
A
Y
J
J
A
mid month of quarter
Fig. 3. Rolling quarterly averages of some PAHs.
Although not recorded here, the particulate loading in the atmosphere was measured, and it was found that there was no correlation or pattern evident between these results and the PAH levels. This data is in agreement with observations made by Mainwaring and Stirling (1981) that PAHs are associated mainly with the smaller diameter aerosols which have correspondingly less effect on the total weight of solid material in the atmosphere. Results of some other studies on atmospheric
PAH concentrations in Australia, Europe, Asia and America are shown in Table3. The levels in Europe. and Asia are, in most cases, at least an order of magnitude above any found in this study. This is probably due to the higher population density and greater use of solid fuels for heating and cooking in these areas. The winter averages for BaP in the towns of Moe and Traralgon were only a little lower than has been found in Melbourne, Ontario and Los Angeles, which
2554
R. J. LVALL rr uf. Table 3. Some PAH levels from other studies
Location
Year
Season
London. U.K. Antony, France
1972:3 1979 1980 1979 1980
All Yr Summer Winter Summer Winter All Yr Summer Winter All Yr Summer Autumn Winwr Spring Winter
St. Denis, France Nuremberg F.R.G. T&wan. lran
19X1
Los Angeles, U.S.A. Los Angeles. U.S.A.
lY71.:2 1974
Melbourne. Australia
1979
1981
BaP (ngm J1
(ngm -‘I
5 IO 0.02 4.h 0.07
3 19 0.14 I .x4 ox?
15.0
3.3
3.47
COR
are cities 100 times larger. This indicates that the nonvehicular PAH pollution at these town sites during winter, is above the level which may be expected in a provincial township. The COR averages at the urban locations were less than 25-50% of the levels recorded in Melbourne and Los Angeles and probably accurately reflect the respective traffic densities. The comparison between the rural site in Los Angeles County and Thorns Bridge is interesting. The yearly average of BaP is nearty identical, while the COR level is 4 times higher at the American site. This indicates that the impact of domestic emissions are similar but that the vehicular traffic is more intense in Los Angeles County. As previously reported, the levels of BaP and COR can be a guide to the origins of the PAW contamination, COR coming mainly from motor vehicle exhausts and BaP from domestic and industrial sources (Kommers, 1976). Blokzijl and Guicherit (1972) have reported that a ratio of BaP to COR of less than 1.0 is indicative of automobile sources, and of greater than 1.7 is indicative of domestic heating sources. For 90 % of the days sampled, this ratio was below 1.0 and on only two occasions did it rise above 1.7.This indicates that the major source of the PAH pollution in this area was due to the automobile. At Morweil East, Moe and Traralgon however, there was a general increase in the BaP/COR ratio in the colder months, which indicated that there was a significant contribution from domestic type sources, although this was still less than that from the automobile. This effect was expected as domestic and commercial heating units would be used to a much greater degree during winter. There were several times during the year when certain PAHs, and in particular BaP, rose to levels which did not fit the general pattern and a comparison of these was made with meteorological data. BaP levels increased at Morwell East on several days when the winds were light and from the southerly quadrant. The relatively high BaP/COR ratio indicated that the
Reference .--
City Residential
Commins and Hampton, 1976. Muel and Saguem. 198s.
Industrial
Muel and Saguem. 1985.
2.5
Urban Urban
Stemmetzer et al., 1984. Aghdaie and Abid. 1986.
0.20 1.13 I.66 4.44 2.49 2.05
Rural Urban
Gordon and Bryan, 1973. Gordon, 1976.
Urban
Mainwaring and Stirling, 1981.
127 X.2Y 0.03 0.17 0.X I.?? 0.77 0.99
Comments
PAH concentration was not due to vehicular sources, and as the daily temperatures were comparatively mild, it was unlikely to be caused by an increase in heating activity. Therefore the rise in BaP levels was probably due to industrial sources. The possible industrial sources of PAH pollution to the south of Morwell were the power stations and the char plant, and considering evidence from this and other studies the source was probably not the power stations. Therefore the most likely source of the atmospheric PAHs on these days was the char plant. At Moe and Traralgon there were several days of high BaP concentration, and on all these days except one, the winds were variable or had a westerly component. As both sites have extensive residential areas in that direction it is probable that the extra BaP levels were due to domestic heating sources. Very low temperatures were recorded in the morning on several of these days, which would lead to an increase in domestic and commercial heating activity. On some of these days there was also a small increase in levels at Thorns Bridge, probably due to a limited transport of the particulate matter from residential areas. increased
REFERENCES Aghdaie N. and Abid S. (1986) Determination of some airborne polycyclic aromatic hydrocarbons in the Tehran atmosphere. Proc. 7th World Clean Air Congress5,68-75. Blokzijl P. J. and Guicherit R. (1972) The occurrence of polynuclear aromatic hydrocarbons (PAH) in outdoor air.
Th’O-Nieuws 27,6X3-660.
Hampton L. (1976) Changing pattern in concentrations of polycycticaromatic hyd&s in the air of Central London. Atmosp~ic EnolnmAleAt I@,
Commins B. T. and
561-562. Gordon R. J. (1976) Distribution of airborne polycyclic aromatic hydrocarbons throughout Los An&es. En&. Sci. Technol. 10,370-373. Gordon R. J. and Bryan R. J. (1973) Patterns in airborne polynuclear aromatic hydrocarborr titration at four Los Angeles sites. Envir. Sei. Technoi. 7, 10504051.
Polycyclic aromatic hydrocarbons in Latrobe Valley Griciutc
L. (1978) Environmental Carcinogens-Sefected Methods of Analysis, 3, Inter. Agency for Research on
Cancer, 3-8. Guerin M, (1978) Energy sources of polycyclic aromatic hydrocarbons. Polycyclic Hydrocarbons and Cancer, 1, Enaironment, Chemistry and Metabolism (edited by H. V. Gelboin and P.O.P.Ts’o), pp. 342. Academic Press, New York. Hangebrauk R. P., von Lehmden D. J. and Meeker J. E. (1967) Sources of Polynuclear Aromatic Hydrocarbons in ;he aimosphere. Env~onmental Health Se&s, U. S. Dept of Health, Public Health Service Publication No. 999-AP33, 9-12. Kommers F. J. W. (1976) Determination of Polycyclic Hydrocarbons in air.1 IG =TNO Research Institute for En-
2555
vironmental Hygiene, Report G 689, pp. l-14. Mainwarina S. J. and Stirlinn D. M. (1981) A Studv of the site dist~but~n and ~n~nt~tions bf poiynucle& aromatic hydrocarbons in melbourne air. i%c. 7th hemat. Clean Air Conf pp. 605-622. Ann Arbor Science. Mucl B. and Saguem S. (1985) Determination of 23 polycyclic aromatic hydrocarbons in atmospheric particulate matter of the Paris area. ht. J. Enoir. Analyl. Chem. 11I-131. Steinmetzer H. C., Baumeister W. and Vierle 0. (1984) Analytical investigation on the contents of polycyclic aromatic hydrocarbons in airborne particulate matter from two Bavarian cities. Sci. total Enuir. 36, 91-96. Yamasaki H., Kuwata K. and Miuamoto H. (1982) Effects of ambient temperature on aspects of airborne polycyclic aromatic hydrocarbons. Entiir Sci. Technol. 16, 189-194.