Particulate matter in ‎air‬‬‬‬‬‬‬‬‬‬‬‬‬‬ affects ‎intelligence,‬‬‬‬‬‬‬‬‬‬‬‬‬‬ especially ‎kids‬‬‬‬‬‬‬‬‬‬‬‬‬‬ and aging seniors.
Change your ceiling air filters every three months.
But invest in a high quality home air filter, like IQ air.
Endocrinology2015Oct;156(10)