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ting the activity of the enzyme arylhydro~ carbon hydroxylase with 7,8-benzoflavone or by reducing the cellular concentration of the enzyme by simultaneous incubation with cycloheximide. These results suggested that in ChaGo cells, the observed covalent com- plexes were formed by the interaction of the BaP metabolites with cellular proteins. The concentrations at which 7,8-benzoflavo- ne or cycloheximide i~hibited (a) formation of metabolites from (H)BaP and (b) their covalent interaction withcell protein did not affect the BaP-induced stimulation of alpha-hCG gene expression. However, the cytotoxic effects of BaP in ChaGo cells seemed to be exerted by the metabolism of the compounds. Results presented in this report suggest that BaP metabolism and the interaction of the metabolites with cell proteins were not essential for the BaP- induced modulation of alpha-hCG gene expres- sion.

Morine Lung Carcinogenesis Following Expo- sure to Ambient Ozone Concentrat ions. Hassett, C., Mustafa, M.G., Coulson, W.F., Elashoff, R.M. Division of Environmental and Occupationsl Health Sciences, School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA 90024, U.S.A.J. Natl. Cancer Inst. 75: 771-777, 1985.

Inbred strain A/J mice, responsive to the chemical induction of pulmonary adeno- mas, were used to assess any of several ro- les that the photochemical air pollutant ozo- ne might play in lung carcnogenesis. In se- parate experiments, animals were exposed to two concentrations of ozone (0.31 + or - o.oi and 0.50 + or - 0.02 ppm) intermittent- ly for a 6-month period, to evaluate the potential of ozone to act as either a pul- monary carcinogen, a tumor promoter, or an inhalant capable of increasing lung tumor yield when exposure was in conjunction with ~pulmonary carcinogen, urethane. Statisti- cal analyses of results indicated that ozone exposure at both concentrations caused an increase in lung tumor number relative to clear air controls, but that ozone was not an effective tumor promoter under the con- ditions of our protocol. When ozone exposu- re immediately preceeded treatment with urethane (CAS; 51-79-6), animals were at in~ creased risk for the development of lung ade- nomas.

Lung Cancer Incidence in a Chinese High Back- ground Area - Epidemiological Results and Theoretical Interpretation, Hofmann, W., Katz, R., Chunxiang, Z. Division of Biophysics, University of Salzburg, A- 5020 Salzburg, Austria. Sci. Total. Environ. 45: 527-534, 1985.

A survey of inhabitant exposures arising

from the inhalation of radon and thoron daughters, and lung cancer mortality has been carried out in two adjacent areas in Guangdong province, China, designated as the 'high back- ground' and the 'control' area. Annual expo- sure rates are 0.38 WLM/yr in the high back- ground, and 0.16 WLM/yr in the control area, while ~ge-adjusted mortality rates are 2.7 per i0- living people of a~l ages in the high background, and 2.9 per i0- in the control area. From this data we conclude that we are unable to determine the excess lung cancer rate over normal fluctuation below a cumula- tive exposure of about 15 WLM. This conclu- sion is supported by lung cancer mortality data from an Austrian high background area.

Mortality Among Workers in the Florida Phos- phate Industry. II. Cause-Specific Mortali- ty Relationships with Work Areas and Expo- sures. Checkoway, H., Mathew, R.M., Hickey, J.L.S. et al. Department of Epidemiology, School of Public Health, University of North Caro- lina, Chapel Hill, NC 27514, U.S.A.J. Occup. Med. 27: 893-896, 1985.

Small excess of lung cancer and emphysema mortality had been detected among an histo- rical cohort of 17,601 white and 4,722 non- white Florida phosphate industry workers. Internal mortality rate comparisons were made between worker subcohorts classified accor- ding to length of employment in 16 work are- as and according to employment duration in jobs grouped by potential exposures to i0 agents, including alpha radiation. The only consistent associations seen were increased lung cancer mortality rates among long-term workers in plant-wide services and skilled crafts jobs. There was no evidence to sup- port causal associations with exposures characteristic of the phosphate industry.

Lung Cancer 1978-1981 in the Black Peoples of South Africa. McGlashan, N.D., Harington, J.S. Department of Geography, University of Tasmania Box 252C, GPO Hobart, Tasmania, 7001, Australia. Br. J. Cancer 52: 339-346, 1985.

Mortality data on lung cancer among the black populations of South Africa, newly a- vailable from the first ever nation-wide enu- merations, are analysed for age-specific rates and significant geographical and inter- tribal variations. This study finds a higher incidence at younger ages than among whites, an urban excess similar to other population groups in South Africa and a higher inciden- ce among the Xhosa than Zulu. It is suggested that an anti-smoking campaign is urgently required among blacks in South Africa.

A Nortality Study of Carbon Black Workers Employed at Five United Kingdom Factories

Between 1947 and 1980.