{
  "id": 9814690,
  "title": "Team figures out how smog begins",
  "url": "https://urgent.news/2026/09/25/team-figures-out-how-smog-begins",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-25T18:43:41.000Z",
  "source": {
    "name": "Futurity",
    "slug": "futurity",
    "url": "https://www.futurity.org/how-smog-begins-3345472/"
  },
  "original_language": "en",
  "account": "Scientists have captured the earliest moments of air pollution formation, shedding light on the creation of key ingredients in urban smog. The research, published in Nature Communications, directly observed fleeting chemical reactions between ozone and isoprene, a gas emitted by trees and other plants. These short-lived molecules, called Criegee intermediates, have long eluded direct observation due to their brief existence and low concentrations. By using an advanced optical technique called cavity ring-down spectroscopy, researchers were able to detect Criegee intermediates as they formed and track their development and decay. This breakthrough provides crucial insights into the initial stages of pollution formation, offering a better understanding of how ozone drives atmospheric chemistry and influences air quality. The study highlights the importance of reducing ground-level ozone, rather than addressing the isoprene produced by trees, to effectively combat air pollution. Isoprene, one of the most abundant atmospheric chemicals, reacts with ozone to form secondary organic aerosols that contribute to haze, light scattering, and lung irritation. While trees are the primary source of isoprene, the findings emphasize the need to control ozone emissions through reducing nitrogen oxides and volatile organic compound precursors. The researchers used the newly gained knowledge to test atmospheric reaction networks, building upon an earlier study that captured Criegee intermediates in simpler reactions involving smaller alkenes. The ability to observe these chemical reactions in real-time opens up new possibilities for improving air quality forecasting models and understanding how fine-particle pollution forms under various environmental conditions. The researchers aim to apply the same techniques to another major class of compounds, pinenes, to further enhance their understanding of the complex chemistry that shapes our atmosphere.",
  "summary": "\"It's like nature was presenting us with a dish, and we had to guess how it was made. Now we have a recipe.\"",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}