The air we breathe is a mixture of different gases made up of 78.1% (by volume) nitrogen, 21% oxygen, 0.9% argon, and 0.04% carbon dioxide. Oxygen is the most abundant gas in the atmosphere, essential ...

The nondescript building near a quiet bend of the Hillsborough River started spewing toxic gas about a decade ago. Inside, workers cleaned medical tools by placing them in bags with a chemical called ...