Rewrite the following paragraphExposure to particulate matter smaller than 25 μm PM25 varies substantially across the world During the period 2011–2015 less than 20 of the population in OECD and high-

The exposure to PM2.5, which refers to particulate matter smaller than 2.5 μm, varies greatly worldwide. Between 2011 and 2015, less than 20% of the population in OECD and high-income nations experienced annual mean concentrations exceeding the WHO guideline of 10 μg/m3. Conversely, over 90% of the population in low-and-middle income countries faced pollution levels surpassing the WHO guidelines. Consequently, these countries had to increase their public spending on medical and healthcare services. Research indicates that air pollution imposes significant health costs on developing countries, with China and India alone accounting for half of the world's premature deaths attributed to air pollution (Lancet Commission, 2016)