Here’s a picture of another unsung device that protects us modern folk from pollutants; in the picture below you’re looking out at my deck through an aluminum wire-mesh screen attached to my kitchen window — and in the background you can see plastic-meshing on a gazebo that Karol, Thomas, and I enjoy on our deck.
Without such screens, opening one’s home or business place to fresh air would be to open it to flies and other irritating, often disease-carrying insects. But the lowly screen keeps those unwanted pollutants out while letting fresh air in.
I’m not sure when the mesh-screen was invented or (more importantly) when it became affordable to the masses, but I know that it was sometime during the 19th century. H.L. Mencken, writing of his childhood in late-19th-century Baltimore, noted that the copper mesh screen was a great advance because, before it arrived (sometime, Mencken suggests, in the 1890s) the only mesh screens that people had were made of iron. These iron screens rusted and proved to be unreliable. Copper — and later aluminum (and more recently plastics) — solved the rust problem.
(See H.L. Mencken, “Two Benefactors of Mankind,” in H.L. Mencken, A Second Mencken Chrestomathy , pp. 161-163.)