Completar frases Air PollutionVersión en línea Text/ Reading por SONIA [ING] [TEC_IN] 1 locally severity concentrations pollution activity invisible visible naturally odorless poorest heavily quality harmful WHAT IS AIR POLLUTION ? Air pollution is the effect caused by of solids , liquids or gases in the air that have a negative impact on the surrounding environment and people . There are many pollutants and they may occur ( from dust , wildfires and volcanoes ) or from human activity , be or , emit an odor or be . Various air pollutants can stay in the atmosphere from minutes to years and , while often considered a local issue , may have a range that is local , national , regional or global . Air is often understood as an urban issue and it is true that cities concentrate economic and demand for energy services , and , so , tend to experience the most concentrations of air pollution . The precise mix of pollutants and the of the health impacts are different from Paris to Delhi , Los Angeles to Lagos , Beijing to Mexico City , but all have air that reduces life expectancy . Air pollution does not stop at the city gate : the sources are widespread , sometimes rural in nature and , although some pollutants disperse only , others travel large distances in the atmosphere and have regional and global impacts . Many of the world ? s communities are exposed to toxic fumes when cooking , or heating and lighting their homes .