{
  "abstract": "Megacities frequently suffer from poor air quality, with PM2.5 concentrations routinely exceeding WHO guidelines and elevating the risk of cardiovascular and respiratory disease. Air quality legislation typically targets primary emissions from traffic, a dominant urban source of PM₂.₅. Here, we present direct, chemically resolved quantification of PM₁ emissions from three contrasting megacity neighbourhoods—London, Beijing and Delhi—revealing the magnitude and diversity of urban sources by applying a novel source attribution approach to eddy-covariance flux measurements using aerosol mass spectrometry. In Delhi, traffic and combustion dominate primary PM₁ emissions. In contrast, cooking is the largest source during mealtimes in London and Beijing, contributing up to 83% of midday emissions and 87% in the early evening in London, and up to 61% and 76%, respectively, in Beijing. These findings suggest that air quality legislation in London and Beijing has effectively reduced non-refractory transport and combustion emissions, allowing cooking to emerge as the largest local source of primary non-refractory PM₁. Although cooking is not included in national, European or global emission inventories, recent estimates from the London Atmospheric Emissions Inventory align well with our observations. Together, these results show that the sources dominating primary non-refractory PM₁ emissions differ from those controlling ambient PM1 mass. Although cooking is now the leading primary source in London and Beijing, further reductions in urban PM₁ will depend on mitigating secondary formation processes.",
  "abstract_shown": true,
  "affiliations": [
    "UK Centre for Ecology & Hydrology, Edinburgh Research Station, Bush Estate, Penicuik, UK",
    "School of Earth and Environmental Sciences, The University of Manchester, Manchester, UK",
    "National Centre for Atmospheric Science, The University of Manchester, Manchester, UK",
    "Department of Chemistry, Colorado State University, Fort Collins, CO USA",
    "Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China",
    "Present Address: School of Earth System Science, Tianjin University, Tianjin, China",
    "Department of Applied Sciences and Humanities, Indira Gandhi Delhi Technical University for Women, Delhi, India",
    "Department of Civil Engineering, Indian Institute of Technology, Roorkee, India",
    "Cooperative Institute for Research in Environmental Sciences (CIRES) and Department of Chemistry, University of Colorado, Boulder, CO USA",
    "TOFWERK AG, Thun, Switzerland",
    "Aerodyne Research Inc, Billerica, MA USA",
    "Zhejiang University, Hangzhou, China",
    "CSIR National Physical Laboratory, New Delhi, India",
    "Department of Natural Sciences, University of Chester, Thornton Science Park, Chester, UK",
    "Present Address: Maastricht University, Maastricht, Limburg Netherlands",
    "Present Address: Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Av. General Ramon Corona 2514, Zapopan, Jalisco Mexico",
    "Present Address: UK Centre for Ecology & Hydrology, Maclean Building, Wallingford, UK"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 20,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Ben Langford",
      "orcid": "0000-0002-6968-5197"
    },
    {
      "affs": [
        0
      ],
      "name": "Chiara, F. Di Marco"
    },
    {
      "affs": [
        0
      ],
      "name": "James M. Cash",
      "orcid": "0000-0002-8567-1377"
    },
    {
      "affs": [
        1,
        2
      ],
      "name": "James D. Allan",
      "orcid": "0000-0001-6492-4876"
    },
    {
      "affs": [
        1
      ],
      "name": "Zixuan Cheng"
    },
    {
      "affs": [
        1,
        2
      ],
      "name": "Hugh Coe"
    },
    {
      "affs": [
        3
      ],
      "name": "Delphine K. Farmer",
      "orcid": "0000-0002-6470-9970"
    },
    {
      "affs": [
        4,
        5
      ],
      "name": "Pingqing Fu",
      "orcid": "0000-0001-6249-2280"
    },
    {
      "affs": [
        6
      ],
      "name": "Ranu Gadi"
    },
    {
      "affs": [
        7
      ],
      "name": "Bhola Ram Gurjar"
    },
    {
      "affs": [
        8
      ],
      "name": "Jose L. Jimenez",
      "orcid": "0000-0001-6203-1847"
    },
    {
      "affs": [
        9,
        10
      ],
      "name": "Joel Kimmel"
    },
    {
      "affs": [
        11
      ],
      "name": "Dantong Liu"
    },
    {
      "affs": [
        12
      ],
      "name": "Tuhin Kumar Mandal"
    },
    {
      "affs": [
        0
      ],
      "name": "Neil J. Mullinger"
    },
    {
      "affs": [
        13,
        14
      ],
      "name": "Gavin J. Phillips"
    },
    {
      "affs": [
        1,
        15
      ],
      "name": "Ernesto Reyes-Villegas",
      "orcid": "0000-0003-4710-2277"
    },
    {
      "affs": [
        0,
        16
      ],
      "name": "Rutambhara Joshi"
    },
    {
      "affs": [
        4
      ],
      "name": "Shivani Shivani"
    },
    {
      "affs": [
        0
      ],
      "name": "Eiko Nemitz",
      "orcid": "0000-0002-1765-6298"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2k09jvfv3bvkw.bib",
  "cited_by": 0,
  "doi": "10.1038/s41612-026-01583-6",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13719519/",
  "id": "2k09jvfv3bvkw",
  "issns": [
    "2397-3722"
  ],
  "landing_url": "https://doi.org/10.1038/s41612-026-01583-6",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Article"
    ],
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      "openalex",
      "1902|Atmospheric chemistry and aerosols"
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  "openalex": "W7223293978",
  "pdf_url": "https://www.nature.com/articles/s41612-026-01583-6_reference.pdf",
  "pmcid": "PMC13719519",
  "pmid": "42964326",
  "published": "2026-10-23",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2k09jvfv3bvkw.ris",
  "sources": [
    {
      "first_seen": "2026-11-02T12:23:28Z",
      "native_id": "PMC13719519",
      "source": "pmc",
      "url": "https://doi.org/10.1038/s41612-026-01583-6"
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  "subjects": [
    {
      "field": "earth",
      "origin": "openalex:1902|Atmospheric chemistry and aerosols",
      "subfield": "atmospheric"
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  ],
  "title": "Traffic and combustion emission controls leave cooking as a dominant local source of primary PM1 in megacities",
  "title_text": "Traffic and combustion emission controls leave cooking as a dominant local source of primary PM1 in megacities",
  "type": "peer-reviewed",
  "updated_at": "2026-11-03T12:20:34Z",
  "url": "https://research.draconitic.com/paper/2k09jvfv3bvkw",
  "venue": "Npj Climate and Atmospheric Science",
  "versions": []
}