As usual, its difficult to nail these attributions down for a long time. Look at arsenic-containing green wallpaper, leaded gasoline, asbestos, and CFCs. They

As usual, its difficult to nail these attributions down for a long time. Look at arsenic-containing green wallpaper, leaded gasoline, asbestos, and CFCs. They were all "fine" and widely-used until it was obvious that they were terrible.