Bungwe la World Health Organization (WHO) linatulutsa lipoti sabata yatha loti anthu oposa 1 miliyoni amafa chifukwa cha chibayo, mphumu, khansa ya m’mapapo ndi matenda ena a m’mapapo angathe kupewedwa padziko lonse chaka chilichonse ngati mayiko atachitapo kanthu kuti mpweya ukhale wabwino. Aka ndi kafukufuku woyamba wamkulu padziko lonse wokhudza kuwonongeka kwa mpweya wakunja padziko lonse lapansi.
Ngakhale kuipitsidwa kwa mpweya ku US sikufanana ndi zomwe zimapezeka m'mayiko monga Iran, India, ndi Pakistan, palibe zokondwerera poyang'ana ziwerengero za California.
Kafukufukuyu amadalira zomwe zanenedwa ndi dziko zaka zingapo zapitazi, ndikuyesa kuchuluka kwa tinthu tating'onoting'ono tochepera 10 ma micrometer - otchedwa PM10s - pafupifupi mizinda 1,100. WHO idatulutsanso tebulo lalifupi loyerekeza milingo ya tinthu tating'onoting'ono ta fumbi, lotchedwa PM2.5s.
WHO imalimbikitsa malire apamwamba a 20 micrograms pa kiyubiki mita kwa PM10s (yofotokozedwa ngati "tanthauzo la pachaka" mu lipoti la WHO), zomwe zingayambitse mavuto aakulu a kupuma mwa anthu. Ma micrograms opitilira 10 pa kiyubiki mita imodzi ya PM2.5s amaonedwa kuti ndi owopsa kwa anthu.
Pamwamba pamndandanda wamizinda yoyipa kwambiri mdziko muno pakuwonetseredwa kochulukira kumagulu onse awiri a tinthu tating'onoting'ono inali Bakersfield, yomwe imalandira ndalama zapachaka za 38ug/m3 kwa PM10s, ndi 22.5ug/m3 kwa PM2.5s. Fresno sali patali, kutenga malo a 2 m'dziko lonselo, ndi Riverside/San Bernardino akudzinenera malo a 3 pa mndandanda wa US. Ponseponse, mizinda yaku California idati 11 mwa anthu 20 olakwa kwambiri m'magulu onsewa, onse omwe amapitilira chitetezo cha WHO.
“Tikhoza kuletsa kufa kumeneku,” anatero Dr. Maria Neira, mkulu wa dipatimenti ya WHO yoona za umoyo wa anthu ndi chilengedwe, amene ananena kuti ndalama zimene anthu amaika pofuna kuchepetsa kuipitsidwa kwa chilengedwe zimalipira msanga chifukwa cha kutsika kwa matenda, motero, kutsika mtengo kwa chithandizo chamankhwala.
Kwa zaka zambiri, ofufuza padziko lonse lapansi akhala akugwirizanitsa kuchepa kwa zinthu ndi nkhalango za m’tauni zathanzi. Kafukufuku wopangidwa ndi bungwe la Natural Environments Research Council m’chaka cha 2007 akusonyeza kuti kuchepetsa PM10 pa 7% -20% kungatheke ngati mitengo yochuluka itabzalidwa, malingana ndi kupezeka kwa malo oyenera kubzala. Ku United States, Center for Urban Forestry Research idasindikiza pepala mu 2006 lomwe likuti mitengo sikisi miliyoni ya Sacramento imasefa matani 748 a PM10 pachaka.