Weeks after a train derailed and crews released and burned toxic chemicals, officials are reassuring residents of East Palestine, Ohio that the air and water are safe.

Many residents, however, remain wary of the long-term effects of materials like vinyl chloride, with some reporting symptoms like skin and eye irritation and hoarseness. Simultaneously, a political conversation is unfolding about who or what to blame for the crash, with critics pointing to a lack of regulation and cost-cutting from rail giants as they post record profits.

Today, a look at what's happening on the ground as residents return to East Palestine, and a look at why rail disasters like this continue to happen more than a decade after the fatal catastrophe in Lac-Mégantic, Quebec.