Cancer Letters, 4 (1977) 5--12 © Elsevier/North-Holland Scientific Publishers Ltd.
5
THE MUTAGENICITY OF AIRBORNE PARTICULATE POLLUTANTS
WALTER DEHNEN, NORBERT PITZ and RENI~ TOMINGAS Medizinisches Institut fi~r Lufthygiene und Silikoseforschung an der Universitdt D~isseldorf, Gurlittstrasse 53, D-4000 Dffsseldorf (G.F.R.)
(Received 19 July 1977) (Revised version received 18 October 1977) (Accepted 19 October 1977)
SUMMARY
The mutagenic effect of extracts derived from airborne particulate matter was investigated with the Ames-test. The whole extract proved to be distinctly mutagenic. To find out whether the content of polycyclic aromatic hydrocarbons may be responsible for the mutagenic effect, the extract was split into several fractions. The fraction containing the polycyclic compounds showed the lowest mutagenic rate that was enzymatically mediated. The other fractions required metabolic activation for some of their components, but some components were active without metabolic activation.
INTRODUCTION
Epidemiological studies suggest a relationship between the particulate matter in the ambient air and the incidence of human bronchus cancer [3,4,6]. The main cancerogenic compounds in airborne particles are thought to be the polycyclic aromatic hydrocarbons (PAH), particularly benzo(a)-pyrene [3,10]. The importance with respect to cancerogenic effects of most of the substances associated with airborne particles is not clear. The bacterial test system introduced by Ames allows rapid detection of mutagens [1]. Initially their test was applied to single compounds [5]. The application was later extended to extracts of particulate matter [7--9]. Talcot and Wei [7] suggest that most of the mutagenic activity of the particulate matter can be attributed to the presence of PAH. Samples of air soot, however, proved to be highly active although no benzo(a)pyrene Could be detected [7]. The correlation between the benzo(a)pyrene content in airborne particulates and mutagenicity was not always positive [8]. These findings, partly contradictory, demand further investigation. The aim of the study presented here was to assess the mutagenic activity in extracts of particulates and that of its fractions with special attention to the PAH-fraction.
MATERIALSAND METHODS 1. Chemicals Methanol, cyclohexene, alumina 90 neutral (Merck, Darmstadt, G.F.R.), were used for extraction and column chromatography. Clophen C, a mixture of polychlorinated biphenyls similar to Aroclor, was a generous gift from Bayer AG, Leverkusen. Histidine was obtained from Merck, glucose 6-phosphate, glucose-6-phosphate
5
THE MUTAGENICITY OF AIRBORNE PARTICULATE POLLUTANTS
WALTER DEHNEN, NORBERT PITZ and RENI~ TOMINGAS Medizinisches Institut fi~r Lufthygiene und Silikoseforschung an der Universitdt D~isseldorf, Gurlittstrasse 53, D-4000 Dffsseldorf (G.F.R.)
(Received 19 July 1977) (Revised version received 18 October 1977) (Accepted 19 October 1977)
SUMMARY
The mutagenic effect of extracts derived from airborne particulate matter was investigated with the Ames-test. The whole extract proved to be distinctly mutagenic. To find out whether the content of polycyclic aromatic hydrocarbons may be responsible for the mutagenic effect, the extract was split into several fractions. The fraction containing the polycyclic compounds showed the lowest mutagenic rate that was enzymatically mediated. The other fractions required metabolic activation for some of their components, but some components were active without metabolic activation.
INTRODUCTION
Epidemiological studies suggest a relationship between the particulate matter in the ambient air and the incidence of human bronchus cancer [3,4,6]. The main cancerogenic compounds in airborne particles are thought to be the polycyclic aromatic hydrocarbons (PAH), particularly benzo(a)-pyrene [3,10]. The importance with respect to cancerogenic effects of most of the substances associated with airborne particles is not clear. The bacterial test system introduced by Ames allows rapid detection of mutagens [1]. Initially their test was applied to single compounds [5]. The application was later extended to extracts of particulate matter [7--9]. Talcot and Wei [7] suggest that most of the mutagenic activity of the particulate matter can be attributed to the presence of PAH. Samples of air soot, however, proved to be highly active although no benzo(a)pyrene Could be detected [7]. The correlation between the benzo(a)pyrene content in airborne particulates and mutagenicity was not always positive [8]. These findings, partly contradictory, demand further investigation. The aim of the study presented here was to assess the mutagenic activity in extracts of particulates and that of its fractions with special attention to the PAH-fraction.
MATERIALSAND METHODS 1. Chemicals Methanol, cyclohexene, alumina 90 neutral (Merck, Darmstadt, G.F.R.), were used for extraction and column chromatography. Clophen C, a mixture of polychlorinated biphenyls similar to Aroclor, was a generous gift from Bayer AG, Leverkusen. Histidine was obtained from Merck, glucose 6-phosphate, glucose-6-phosphate
