Heavy metals in organs of stray dogs and cats from the city of Naples and its surroundings (Southern Italy).

The aim of the present study was to assess the concentrations of lead (Pb) and cadmium (Cd) in the liver and kidney from stray dogs (Canis lupus familiaris) and cats (Felis catus) found dead between 2014 and 2017 in the city of Naples and its surrounding areas. These organs from 290 dogs and 88 cats were collected after ordinary necropsy of stray animals. Heavy metal concentrations were determined by using atomic absorption spectrophotometry (AAS). Concentrations of Pb (up to 5.93 mg/kg) and Cd (ranging from 0.005 to 6.13 mg/kg) were detected in both livers and kidneys analyzed. Differences in concentration were found based on age class, gender, and kind of tissue for both elements, with a trend similar to those already reported in the literature for comparable studies from different countries. Cadmium levels in the kidney were significantly higher (p < 0.05) in females than those in males for both species. As regards to Pb, the highest concentrations were detected in the liver (3.45 mg/kg in dog and 5.93 in cat, respectively) followed by the renal tissue, with no significant difference depending on the animal gender. This study can be considered the first one in Italy regarding stray dogs and cats as bio-indicators of environmental contamination due to lead and cadmium, suggesting that pets could be sentinel animals to evaluate human exposure to these heavy metals.