AimThere is a generalized consensus concerning the ecological importance of herpetofauna and its high sensitivity to the environmental pollution. However, reptiles continue to be under-utilized as sentinel species in ecotoxicological studies. The magnitude of the impact of environmental pollution on lizards is analyzed in the present study using lizard tail tips for the quantitative evaluation of enzymatic biomarkers of pollution.
MethodsTwo lizard species (Sceloporus serrifer and S. torquatus) were captured using the noose technique from May to June 2009 from two suburban localities in the Monterrey Metropolitan Area, Mexico: Chipinque Ecological Park (EP), a natural protected area, and El Carmen Industrial Park (IP), a highly polluted site. Tail tips were taken manually (c. 3cm) in order to produce enzymatic extracts and measure the levels of activity from 7 different enzymes.
ResultsAt IP 27 samples were taken from S. serrifer, 19 at EP and 7 from S. torquatus at EP. Three enzymes showed no significant differences between localities (commonly used as biomarkers of neurotoxic polluting agents). In contrast, the levels of 4 enzymes were significantly different between localities. Showing a clear physiological effect in the population of spiny lizards at IP undoubtedly due to polluting agents such as heavy metals and/or hydrocarbons.
ConservationThe biochemical biomarkers can be determined with simpler and/or more economic equipment that those necessary for residue analysis, which can facilitate a wider use of these biomarkers. The present work validates the possibility of conducting additional ecotoxicological studies using biomarkers in combination with a nondestructive sampling technique in species of spiny lizards that are abundant in many North America areas.