In 1976, the New York Giants professional football team relocated to the newly constructed Meadowlands Sports Complex (MSC) in East Rutherford, NJ. Between 1980 and 1987 four team members developed cancer: one case each of non-Hodgkin's lymphoma, glioblastoma, angiosarcoma, and Hodgkin's disease. Because the surrounding area contains three superfund sites, concern was widespread that the cancers were related to environmental contamination. To assess for a possible environmental etiology, we conducted clinical, environmental, and epidemiologic studies at the MSC. Measurements of volatile organic compounds were all below occupational exposure limits and were similar to ambient levels in nearby Lyndhurst, NJ. Outdoor AM radio broadcast field strengths were in the uppermost 0.1% of field strengths measured in urban areas of the United States. Proportionate mortality ratio and proportional cancer incidence ratio studies of the MSC workforce found no excesses of cancer deaths or of incident cancer cases either for all sites combined or for any specific site. No significant differences in cancer incidence or mortality were found between indoor and nonindoor workers. Based on examination of all available data, the four cancer cases were judged most likely to have been clustered by chance and not to have been caused by environmental conditions at the MSC.