New Orleans Lizards Exhibit Highest Blood-Lead Levels Recorded

Recent research by Tulane University has revealed that brown anole lizards in New Orleans carry the highest blood-lead levels ever recorded in a vertebrate, with concentrations far exceeding lethal levels for most animals. Despite blood lead levels averaging nearly 1,000 micrograms per deciliter and some lizards reaching over 3,000, these invasive lizards not only survive but thrive, showing no decline in physical performance traits such as balance, sprint speed, and endurance. This resilience is remarkable given lead's potent neurotoxic effects, which typically cause severe damage and death in other vertebrates at much lower concentrations. The brown anoles, originally from the Caribbean and established in New Orleans since the 1990s, have become more numerous than the native green anole species. The findings challenge existing toxicity thresholds for vertebrates and suggest that understanding the lizards' physiological and genetic adaptations could inform strategies to mitigate lead poisoning in humans and wildlife. This study highlights the complex legacy of lead contamination in urban environments like New Orleans and the surprising ways some species adapt to extreme pollution.