Introduction Exposure to lead and cadmium is a public health problem owing to the wide exposure to these toxic substances among the general population. The objective of this study is to determine blood lead and cadmium concentrations in a working population drawn from four university hospitals in Madrid, Getafe, Cartagena and Santiago de Compostela, and to identify associated factors. Materials and Methods A total of 252 subjects took part in the study and were given the standardised PESA® questionnaire on exposure to lead and cadmium. The blood lead and cadmium concentrations were measured by electrothermal atomization atomic absorption spectrometry with Zeeman background correction in Perkin-Elmer spectrometers, guaranteeing the transferability of the results. Results The median overall blood lead concentration was: 2.0 μg/dL ( Interquartile Range (IQR):1.2–3.1) and that of cadmium was: 0.2 μg/L (IQR: 0,1–0,4). The median of lead in post-menopausal women was higher (2.9 μg/dL) than that of pre-menopausal women (1.3 μg/dL) P<0.001. The median of cadmium in subjects who smoked (0.54 μg/L) was higher than that in non-smokers (0.21 μg/L) P<0.001. Conclusions A reduction in blood lead and cadmium levels was observed with respect to previous studies carried out in Spain. Nevertheless, the results suggest there are certain factors which increase the risk, such as age, menopause, age of housing and exposure to cigarette smoke.