Using an indicator-based approach, we assessed environmental hazards and related health effects in populations of industrial cities with more than 100,000 inhabitants in Upper Silesia, Poland, and analyzed the relationship between environment and health. We adopted the method developed by Dutkiewicz et al. for assessing large geographic areas. Based on routinely collected environmental and health data, two groups of indicators, environmental indicators (EIs) and health status indicators (HSIs), related to environmental contamination were selected. The EI and HSI values were normalized and aggregated into synthetic measures using Strahl's taxonometric method. The synthetic measures indicated the intensity of environmental hazards and health outcomes. We used a three-level index scale to compare and rank the cities under the study and, consequently, to facilitate decision making. Findings of the assessment identified cities where actions aimed at reducing environmental hazards and improving population health status should be established as priorities. These cities included Chorzów, Katowice, Sosnowiec, Bytom, and Zabrze. We found a high correlation between the synthetic measures of environmental indicators and the synthetic measure of health status indicators (r = 0.77), as well as a high level of consistency between environmental hazard indices and environmental-related health status indices (73%). This may indicate the existence of a causal relationship between the environmental contamination within industrial cities and the health status of their inhabitants.