Revealed: Mexico’s industrial boomtown is making goods for the US. Residents say they’re ‘breathing poison’

Polluting facilities in Monterrey, which has close ties to the US, are pumping toxic heavy metals into the city’s air and threatening residents’ healthLeer en español en Quinto Elemento LabAn industrial boom in a US manufacturing hub in Mexico is contributing to a massive air pollution crisis that is threatening residents’ health, according to new research by the Guardian and Quinto Elemento Lab.The polluting facilities in Monterrey include factories that are operated by