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When diagnosed as primary lung cancer, metastases from the abdomen, plus false negative cases have little effect on epidemiology studies of male smokers, but may result in a severe dilution of the lung cancers among women and nonsmokers. We have attempted to quantitate this handicap for epidemiological studies using two approaches. The relative frequency of diagnosed primary lung and abdominal cancer among males, women, and nonsmokers differs substantially and is used here to calculate magnitude. The second approach postulates that the ratio of nonsmokers among persons with squamous cell lung cancer and primary adenocarcinoma of the lung would be constant by sex if there were no distortion by abdominal metastases. These two approaches indicate that the much higher ratio of metastatic disease diagnosed as primary lung cancer among nonsmoking women (factor of 15 to 20), makes it more difficult to identify an environmental carcinogen among women or nonsmokers than among male smokers in case-control studies. Copyright 2000 Harcourt Publishers Ltd

The mortality rates from anencephalus from 1950-1969 in Canadian cities are shown to be strongly correlated with city growth rate and with horizontal geomagnetic flux, which is directly related to the intensity of cosmic radiation. They are also shown to have some association with the magnesium content of drinking water. Prior work with these data which showed associations with magnesium in drinking water, mean income, latitude and longitude was found to be inadequate because it dismissed the observed geographic associations as having little biological meaning, and because the important variables of geomagnetism and city growth rate were overlooked.

The concentrations of 210Pb and 210Po in samples of rib and vertebra from 22 uranium miners are compared to the miners' 222Rn daughter exposures. A correction was made for the excretion of 210Pb from the skeleton during the time interval of exposure to the end of their mining experience and to the miners' death. A correlation was observed between the log of the 210Pb concentration in bone and the log of the miners' cumulative exposure adjusted for Pb excretion to the end of the mining experience, R = 0.92 (P < 0.001). More 210Pb was observed in the bone than was predictable from exposure to short-lived 222Rn daughters alone, and the possible source of this 210Pb is discussed. In addition, a linear correlation was observed between the 210Pb concentration in blood to that in the bone samples, R = 0.85 (P = 0.005). The use of blood 210Pb levels to estimate cumulative exposure in a mine atmosphere appears promising, and the possibility is discussed.