For days, authorities have been telling residents of the area around East Palestine, Ohio, that it is safe to return home after a 150-car train carrying hazardous chemicals derailed Feb. After the controlled burn, the Environmental Protection Agency warned area residents of possible lingering odors but noted that the byproducts of vinyl chloride can emit smells at levels lower than what is considered hazardous. She added that her department has received no reports of residents' experiencing abnormal symptoms