The perovskite solar cells (PSCs) have attracted considerable interest and potential commercial application as lead-based PSCs due to high efficiency and low manufacturing cost. On the other hand, the presence of lead (Pb) in the perovskite structures poses major risk factor in terms of environmental and human health. This chapter focuses and summarises the available acquaintance on Pb toxicity in PSCs, concentrating on physical and chemical properties of Pb in those materials, its environmental hazards, and future perspectives for both solar cell industry and the global ecosystem. The pathways through which Pb could potentially leach out of the perovskite materials throughout the entire life cycle of the product, from manufacturing to operating, how the product is disposed of and the risk of pollution to the environment are also explored. This chapter has also evaluated the existing methodologies for dealing with Pb toxic effects including encapsulation methods and substitutive techniques aiming to develop Pb-free substitutes. In addition, however, as these methods alone will not be sufficient and then outlined what kinds of research will be needed to overcome these issues in the future, in particular, how the safety and sustainability of perovskite solar devices can be improved. This chapter highlights the necessity of cross-disciplinary approaches to allow the full potential of PSCs to be achieved without degrading the environment and human well-being.