The role of UV-visible slitlamp densitography in monitoring 'pre-cataractous' changes in the living human (as well as animals) lens has been amply documented. This apparatus can be easily employed in the field (as a part of an epidemiologic study) and provides biometric as well as densitographic data. These can be correlated with a concomitant evaluation of two cataractogenic risk factors (UV exposure and diet). In addition, all cataractous lenses (or lens matter) removed in the area being studied can be collected, stored in a frozen state, and shipped to the laboratory for further analysis. We have shown that spectroscopic studies (UV, fluorescence, phosphorescence and EPR) can be correlated with these in vivo data and further clarify the role of UV radiation and diet as part of such an epidemiologic study.