News

  1. Chemistry

    Vaping’s toxic vapors come mainly from e-liquid solvents

    New study homes in on a primary source of toxic vaping compounds: the thermal breakdown of solvents used to dissolve flavorings in e-liquids. And older, dirtier e-cigs generate more of these toxicants, study shows.

    By Janet Raloff
  2. Genetics

    Dolly the Sheep’s cloned sisters aging gracefully

    Cloning doesn’t cause premature aging in sheep.

    By Tina Hesman Saey
  3. Earth

    Ancient air bubbles could revise history of Earth’s oxygen

    Pockets of ancient air trapped in rock salt for around 815 million years suggest that oxygen was abundant well before the first animals appear in the fossil record.

    By Thomas Sumner
  4. Cosmology

    Debate accelerates on universe’s expansion speed

    A puzzling mismatch is plaguing two methods for measuring how fast the universe is expanding.