Cadmium, copper and lead in cataractous and normal dog lenses.

Purpose This study aims to determine the concentrations of cadmium (Cd), copper (Cu) and lead (Pb) in cataractous and normal dog lens. The possible role of these elements in cataractogenesis has been suggested by reports in humans. Methods 14 cataracts dogs lenses and a control group of 6 normal clear dogs lenses of different breeds and sex living in same area have been examined. The average ages of the cataractous group are 9.6+/‐4,6 years old, while the control group are 4,8+/‐2,9 years old. Cataractous lenses were classified as mature. Removed lenses were placed into cleaned PVC tubes and kept frozen below ‐20°C before being assayed. Cd, Cu and Pb levels of the samples were determined with a Perkin‐Elmer atomic absorption spectrophotometer equipped with graphite furnace system using a standard addition technique. The concentrations were calculated in terms of mg/kg dry tissue weight. Statistical method used was Student t test. Results Cataractous lenses: Cd 0,081+/‐0,046; Cu 2,9+/‐1,5; Pb <0,05. Normal lenses: Cd 0,062+/‐0,035; Cu 3,6+/‐3,8; Pb <0,05. No significant differences in Cd, Cu and Pb concentrations related to age and sex have been found at the comparison of normal versus cataractous lens Conclusion In humans and animals the most likely origin of Cd, Cu and Pb is from environmental contamination. The results suggest that the low concentrations of these heavy metals in cataractous lens in dogs can be related to the fact that: a) dogs have a shorter lifespam than men; b) these elements are not widely spread in the Italian environment; c) the pattern of absorption and storage of these elements could vary among different species. [ABSTRACT FROM AUTHOR]