Breathing in lingering, secondhand e-cigarette vapors has the potential to damage lung tissues. This is the warning of a new study by researchers from the University of California Riverside, who found that aged vape aerosols contain fine particles bearing metals and highly reactive compounds that can combine to produce harmful radical particles. "Our study reveals that the chemical cocktail of metal nanoparticles and reactive peroxides in aged e-cigarette aerosols creates a unique profile of