Biological impact of lead from halide perovskites reveals the risk of introducing a safe threshold

TLDR

Regulations claim perovskite solar cells contain low, safe levels of lead, yet the true environmental impact of this lead remains unknown. Our data show that lead from perovskite penetrates soil and the food chain tenfold more efficiently than other lead sources, indicating that replacing lead with tin or other inert metals is essential and that perovskite lead content must be regulated below levels used in other electronics.

Abstract

Regulations currently in force enable to claim that the lead content in perovskite solar cells is low enough to be safe, or no more dangerous, than other electronics also containing lead. However, the actual environmental impact of lead from perovskite is unknown. Here we show that the lead from perovskite leaking into the ground can enter plants, and consequently the food cycle, ten times more effectively than other lead contaminants already present as the result of the human activities. We further demonstrate that replacing lead with tin represents an environmentally-safer option. Our data suggest that we need to treat the lead from perovskite with exceptional care. In particular, we point out that the safety level for lead content in perovskite-based needs to be lower than other lead-containing electronics. We encourage replacing lead completely with more inert metals to deliver safe perovskite technologies.