Nkhani Yapadziko Lonse
Persistent organic pollutants (POPs) ndi mankhwala oopsa omwe amawononga thanzi la anthu komanso chilengedwe padziko lonse lapansi. Chifukwa amatha kunyamulidwa ndi mphepo ndi madzi, ma POP ambiri opangidwa m'dziko limodzi amatha kukhudza anthu ndi nyama zakuthengo kutali ndi komwe amagwiritsidwa ntchito ndi kumasulidwa. Zimapitirizabe kwa nthawi yaitali m'chilengedwe ndipo zimatha kuwunjikana ndi kudutsa kuchokera ku mtundu umodzi kupita ku wina kudzera muzitsulo za zakudya. Pofuna kuthana ndi vutoli padziko lonse lapansi, United States inagwirizana ndi mayiko ena a 90 ndi European Community kuti asayine pangano la United Nations ku Stockholm, Sweden, mu May 2001. Pansi pa mgwirizanowu, wotchedwa Stockholm Convention, mayiko adagwirizana kuchepetsa kapena kuthetsa kupanga, kugwiritsa ntchito, ndi / kapena kumasulidwa kwa POPs 12 (onani bokosi), ndi kufotokozedwa pansi pa Mgwirizanowu ndi POP yokhudzana ndi ndondomeko ya sayansi ya padziko lonse.
Ma POP ambiri omwe adaphatikizidwa mumgwirizano wa Stockholm sakupangidwanso mdziko muno. Komabe, nzika zaku US ndi malo okhala zitha kukhala pachiwopsezo kuchokera ku POPs zomwe zalimbikira zachilengedwe kuchokera ku ma POP opangidwa mwangozi omwe amatulutsidwa ku United States, kuchokera ku ma POP omwe amatulutsidwa kwina ndikunyamulidwa kuno (ndi mphepo kapena madzi, mwachitsanzo), kapena kuchokera zonse ziwiri. Ngakhale kuti mayiko ambiri otukuka achitapo kanthu mwamphamvu kuwongolera ma POP, mayiko ambiri omwe akutukuka kumene angoyamba kumene kuletsa kupanga, kugwiritsa ntchito, ndi kumasulidwa kwawo.
Msonkhano wa Stockholm umawonjezera mbali yofunika yapadziko lonse ku zoyesayesa zathu zapadziko lonse ndi zigawo zowongolera ma POP. Ngakhale dziko la United States silinakhale Chipani ku Msonkhano wa Stockholm, Msonkhanowu wachita mbali yofunika kwambiri poletsa mankhwala owopsa padziko lonse lapansi komanso padziko lonse lapansi. Mwachitsanzo, EPA ndi mayiko achepetsa kwambiri kutulutsidwa kwa ma dioxin ndi furan kumtunda, mpweya, ndi madzi kuchokera ku US magwero. Kuphatikiza pakuwunika ma dioxin, EPA yakhala ikugwiranso ntchito molimbika pakuchepetsa DDT kuchokera kuzinthu zapadziko lonse lapansi. United States ndi Canada zinasaina mgwirizano wa Virtual Elimination of Persistent Toxic Substances in the Great Lakes kuti achepetse mpweya wochokera ku zinthu zapoizoni. United States yasainanso ndondomeko yachigawo ya United Nations Economic Commission for Europe on POPs pansi pa Convention on Long-Range Transboundary Air Pollution yomwe ikukamba za Stockholm Convention POPs ndi mankhwala ena.
Kuphatikiza pa mapangano okhudzana ndi ma POP omwe United States adasaina nawo, United States yaperekanso chithandizo chokwanira chandalama ndi luso kumayiko padziko lonse lapansi pothandizira kuchepetsa ma POP. Zina mwazinthuzi zikuphatikiza zotulutsa dioxin ndi furan ku Asia ndi Russia, komanso kuchepetsa magwero a PCB ku Russia.
Kodi POPs Ndi Chiyani?
Ma POP ambiri adagwiritsidwa ntchito kwambiri pakukula kwa mafakitale pambuyo pa Nkhondo Yachiwiri Yapadziko Lonse, pamene zikwi zambiri za mankhwala opangira zidayamba kugwiritsidwa ntchito pamalonda. Ambiri mwa mankhwala amenewa anali othandiza polimbana ndi tizirombo ndi matenda, kalimidwe ka mbewu, ndiponso m’makampani. Mankhwala omwewa, komabe, akhala ndi zotsatira zosayembekezereka pa thanzi la munthu ndi chilengedwe.
Anthu ambiri amawadziwa bwino ma POP odziwika bwino, monga ma PCB, DDT, ndi ma dioxin. POPs imaphatikizapo zinthu zingapo zomwe zimaphatikizapo:
Mankhwala opangidwa mwadala omwe amagwiritsidwa ntchito pano kapena kale omwe amagwiritsidwa ntchito paulimi, kuwongolera matenda, kupanga, kapena njira zamafakitale. Zitsanzo zikuphatikizapo ma PCB, omwe akhala othandiza pa ntchito zosiyanasiyana za mafakitale (mwachitsanzo, mu ma transformer a magetsi ndi ma capacitor akuluakulu, monga hydraulic ndi madzi osinthanitsa ndi kutentha, komanso zowonjezera pa utoto ndi mafuta) ndi DDT, yomwe imagwiritsidwabe ntchito poletsa udzudzu umene umanyamula malungo m'madera ena a dziko lapansi.
Mankhwala opangidwa mosadziwa, monga ma dioxin, omwe amabwera chifukwa cha njira zamafakitale komanso kuyaka (mwachitsanzo, kuyatsa zinyalala zamatauni ndi zachipatala ndi kuyatsa zinyalala kuseri kwa nyumba).
The DDT Dilemma
DDT mwachionekere ndi imodzi mwa mankhwala ophera tizilombo otchuka kwambiri ndiponso ochititsa mkangano omwe anapangidwapo. Pafupifupi mapaundi mabiliyoni a 4 a mankhwala otsika mtengo komanso a mbiri yakale amapangidwa ndikugwiritsidwa ntchito padziko lonse lapansi kuyambira 1940. Ku United States, DDT inagwiritsidwa ntchito kwambiri pa mbewu zaulimi, makamaka thonje, kuyambira 1945 mpaka 1972. DDT inagwiritsidwanso ntchito kuteteza asilikali ku matenda oyambitsidwa ndi tizilombo monga malungo ndi typhus m'madera ofunika kwambiri a zaumoyo pa nthawi ya nkhondo yachiwiri ya padziko lonse. Kugwiritsa ntchito kwambiri mankhwalawa kosalekeza, komabe, kudadzetsa kufalikira kwa chilengedwe komanso kuchuluka kwa DDT mwa anthu ndi nyama zakuthengo - chodabwitsa chomwe chinadziwika ndi Rachel Carson m'buku lake la 1962, Silent Spring. Kuchuluka kwa labotale yasayansi ndi deta yam'munda tsopano yatsimikizira kafukufuku wazaka za m'ma 1960 zomwe zikuwonetsa, mwa zotsatira zina, kuti kuchuluka kwa DDE (metabolite ya DDT) m'mbalame zina zomwe zimadya nyama zidapangitsa kuti zipolopolo zawo za mazira zikhale zoonda kwambiri kotero kuti sizingabereke ana amoyo.
Mbalame imodzi imene imakhudzidwa kwambiri ndi DDE inali ya chiwombankhanga. Kudetsa nkhaŵa kwa anthu ponena za kuchepa kwa ziombankhanga ndi kuthekera kwa zotsatira zina zovulaza kwa nthaŵi yaitali za kuonetsedwa kwa DDT kwa anthu ndi nyama zakuthengo kunasonkhezera bungwe la Environmental Protection Agency (EPA) kuletsa kulembetsa kwa DDT mu 1972. Chiwombankhangacho chakhala chikukumana ndi chimodzi mwa mitundu yochititsa chidwi kwambiri imene yapulumuka m’mbiri yathu.
Oyenda Odutsa malire
Fumbi Lapadziko Lonse: Chithunzichi chikuwonetsa chithunzi cha satellite chodutsa mtambo wafumbi kudutsa nyanja ya Pacific kupita ku North America. Mtambo wafumbi umenewu unadzutsidwa ndi chimphepo chamkuntho ku Asia mu April 2001. Chikusonyezedwanso mtambo wa fumbi wochokera kumpoto kwa Afirika ukuyenda kumadzulo pamwamba pa nyanja ya Atlantic.
Cholimbikitsa chachikulu pa Msonkhano wa Stockholm chinali kupezeka kwa kuipitsidwa kwa ma POPs m'zigawo za Arctic - masauzande a mailosi kuchokera kulikonse kodziwika. Umboni wambiri wonyamula zinthu zamtundu wautali ndi mpweya kupita ku United States umayang'ana pafumbi kapena utsi chifukwa amawonekera pazithunzi za satellite. Kufufuza kusuntha kwa ma POP ambiri m'chilengedwe kumakhala kovuta chifukwa mankhwalawa amatha kukhalapo m'magawo osiyanasiyana (mwachitsanzo, ngati mpweya kapena womangiriridwa ku tinthu tating'onoting'ono ta mpweya) ndipo amatha kusinthanitsa ndi chilengedwe. Mwachitsanzo, ma POP ena amatha kunyamulidwa kwa mailosi ambiri akamasanduka nthunzi m'madzi kapena pamtunda kupita mumlengalenga, kapena akamakondera ku tinthu tating'onoting'ono ta mpweya. Kenako, amatha kubwerera ku Dziko Lapansi pa tinthu tating'onoting'ono kapena matalala, mvula, kapena nkhungu. Ma POP amayendanso m’nyanja, m’mitsinje, m’nyanja, ndipo, mocheperapo, mothandizidwa ndi zonyamulira nyama, monga zamoyo zimene zimasamuka.
Kodi Ndi Zochita Zotani Zapakhomo Zachitidwa Kuti Kuwongolera Ma POP?
United States yachitapo kanthu mwamphamvu kunyumba kuti achepetse mpweya wa POPs. Mwachitsanzo, palibe mankhwala ophera tizilombo oyambilira a POPs omwe adalembedwa mu Stockholm Convention omwe adalembetsedwa kuti agulitse ndikugawira ku United States lero ndipo mu 1978, Congress idaletsa kupanga ma PCB ndikuletsa kwambiri kugwiritsa ntchito masheya otsala a PCB. Kuphatikiza apo, kuyambira 1987, EPA ndi mayiko achepetsa kutulutsa kwachilengedwe kwa ma dioxin ndi furan kumtunda, mpweya, ndi madzi kuchokera ku US magwero. Zochita zowongolera izi, limodzi ndi zoyesayesa zodzifunira zamakampani aku US, zidapangitsa kutsika kwakukulu kopitilira 85 peresenti ya zotulutsa zonse za dioxin ndi furan pambuyo pa 1987 kuchokera kumafakitale odziwika. Kuti mumvetse bwino kuopsa kokhudzana ndi kutulutsidwa kwa dioxin, EPA yakhala ikuwunikanso mwatsatanetsatane sayansi ya dioxin ndipo ikuwunikanso zina zomwe zingatetezere thanzi la anthu komanso chilengedwe.
Kuyimitsa Kugwiritsa Ntchito DDT
Kwa zaka zambiri, United States yatenga njira zingapo zoletsa kugwiritsa ntchito DDT:
1969: Pambuyo pophunzira kulimbikira kwa zotsalira za DDT m’chilengedwe, Dipatimenti ya Zaulimi ya ku United States (USDA) inaletsa kulembetsa ntchito zina za DDT (pamitengo ya mithunzi, pa fodya, m’nyumba, ndi m’malo okhala m’madzi).
1970: USDA inaletsa ntchito za DDT pa mbewu, zamalonda, ndi zinthu zamatabwa, komanso zomanga.
1972: Pansi pa ulamuliro wa EPA, kulembetsa kwa zinthu zotsala za DDT kuthetsedwa.
1989: Kugwiritsa ntchito kotsala kosaloledwa (kugwiritsa ntchito paumoyo wa anthu powongolera matenda oyambitsidwa ndi ma vector, kugwiritsa ntchito usilikali m'malo okhala kwaokha, komanso kugwiritsa ntchito mankhwala osokoneza bongo poletsa nsabwe zam'thupi) zimayimitsidwa modzifunira.
Lero: Palibe kulembetsa ku US kwa DDT, kutanthauza kuti sikungagulitsidwe mwalamulo kapena kugawidwa ku United States.
Kuwongolera Dioxins
EPA yatsata kuwongolera ndi kuyang'anira ma dioxins ndi ma furan omwe amatulutsidwa ku mpweya, madzi, ndi nthaka. The Clean Air Act imafuna kugwiritsa ntchito ukadaulo wowongolera womwe ungatheke pakuwononga mpweya wowopsa, kuphatikiza ma dioxin ndi ma furan. Magwero akuluakulu omwe amalamulidwa ndi bomali akuphatikizapo kutenthetsa zinyalala zazachipatala, zazachipatala, ndi zoopsa; kupanga zamkati ndi mapepala; ndi njira zina zopangira ndi kuyenga zitsulo. Kutulutsidwa kwa dioxin m'madzi kumayendetsedwa ndi zida zotengera zoopsa komanso zaukadaulo zomwe zidakhazikitsidwa pansi pa Clean Water Act. Kuyeretsa malo okhala ndi dioxin ndi gawo lofunikira la EPA Superfund ndi Resource Conservation and Recovery Act Corrective Action. Zochita zodzifunira zothana ndi ma dioxin ndi ma furan zikuphatikizapo EPA's Persistent, Bioaccumulative, and Toxics Programme ndi Dioxin Exposure Initiative, zomwe zimasonkhanitsa zambiri kuti zidziwitse zomwe zidzachitike m'tsogolo ndi kuchepetsanso zoopsa zomwe zimagwirizanitsidwa ndi dioxin.
Kodi ma POP Amakhudza Bwanji Anthu ndi Zinyama Zakuthengo?
Kafukufuku wagwirizanitsa kuwonekera kwa POPs ndi kuchepa, matenda, kapena zolakwika zamitundu ingapo ya nyama zakuthengo, kuphatikiza mitundu ina ya nsomba, mbalame, ndi zoyamwitsa. Zinyama zakuthengo zimathanso kukhala ngati oyang'anira thanzi la anthu: zolakwika kapena kuchepa komwe kumapezeka muzanyama zakuthengo kumatha kuyimba belu lochenjeza anthu. Kusokonezeka kwamakhalidwe ndi zilema zobadwa mu nsomba, mbalame, ndi zoyamwitsa mkati ndi kuzungulira Nyanja Yaikulu, mwachitsanzo, zidapangitsa asayansi kuti afufuze kuwonekera kwa POPs mwa anthu (onani m'munsimu kuti mudziwe zambiri za Nyanja Yaikulu).
Mwa anthu, kubereka, kakulidwe, kakhalidwe, neurologic, endocrine, ndi zotsatira zoyipa za thanzi la immunological zalumikizidwa ndi POPs. Anthu amakhudzidwa kwambiri ndi ma POPs kudzera muzakudya zomwe zili ndi kachilombo. Njira zomwe sizidziwika bwino ndi monga kumwa madzi owonongeka komanso kukhudzana mwachindunji ndi mankhwalawo. Mwa anthu ndi nyama zina zoyamwitsa, ma POP amatha kusamutsidwa kudzera mu nkhokwe ndi mkaka wa m'mawere kupita ku ana obadwa. Komabe, ziyenera kudziŵika kuti mosasamala kanthu za kuvulazidwa kumeneku, ubwino wodziŵika wa kuyamwitsa umaposa kuopsa kokayikiridwa.
Anthu angapo ali pachiwopsezo chotenga ma POPs, kuphatikiza anthu omwe zakudya zawo zimakhala ndi nsomba zambiri, nkhono, kapena zakudya zakuthengo zomwe zili ndi mafuta ambiri komanso zomwe zimapezeka kwanuko. Mwachitsanzo, eni eni eni eni omwe ali pachiwopsezo chachikulu chifukwa amatsatira miyambo ndi miyambo yauzimu yokhudzana ndi zakudya zawo. Kwa iwo, kusodza ndi kusaka simasewera kapena zosangalatsa, koma ndi gawo la moyo wachikhalidwe, momwe palibe gawo lothandiza la nsomba zomwe zimawonongeka. Kumadera akumidzi a Alaska ndi kwina, chakudya chopezeka m'deralo chikhoza kukhala njira yokhayo yopezera zakudya (onani m'munsimu kuti mudziwe zambiri za Arctic).
Kuphatikiza apo, anthu omwe ali ndi chidwi, monga ana, okalamba, ndi omwe ali ndi chitetezo chamthupi choponderezedwa, nthawi zambiri amakhala pachiwopsezo cha mitundu yambiri ya zoipitsa, kuphatikiza ma POP. Chifukwa chakuti ma POP akhala akugwirizana ndi zolepheretsa kubereka, amuna ndi akazi a msinkhu wobereka angakhalenso pangozi.
POPS ndi Chakudya Chakudya
Ma POP amadutsa mumchenga wa chakudya mwa kuwunjikana m'thupi la mafuta a zamoyo ndi kukhala okhazikika pamene akuyenda kuchokera ku cholengedwa china kupita ku china. Njira imeneyi imadziwika kuti "biomagnification." Zowononga zikapezeka pang'onopang'ono pansi pa chain biomagnify, zitha kukhala pachiwopsezo chachikulu kwa adani omwe amadya pamwamba pa mndandanda wazakudya. Izi zikutanthauza kuti ngakhale kutulutsa kwakung'ono kwa POP kumatha kukhala ndi zotsatirapo zazikulu.
Biomagnification in Action: Kafukufuku wa 1997 wochitidwa ndi Arctic Monitoring and Assessment Programme, yotchedwa Arctic Pollution Issues: A State of the Arctic Environment Report, anapeza kuti caribou ku Canada's Northwest Territories inali ndi milingo ya PCB yochuluka kuwirikiza ka 10 kuposa ndere imene ankadyerapo; Miyezo ya PCB m’mimbulu imene imadya pa caribou inakulitsidwa pafupifupi kuŵirikiza ka 60 kuposa ndere.
Udindo wa Sayansi
Ngakhale asayansi ali ndi zambiri zoti aphunzire za mankhwala a POPs, zaka zambiri za kafukufuku wasayansi zawonjezera chidziwitso chathu cha momwe ma POP amakhudzira anthu ndi nyama zakuthengo. Mwachitsanzo, kafukufuku wa labotale awonetsa kuti kutsika kwa ma POP ena kumakhudza kwambiri ziwalo zina ndi kakulidwe. Kafukufuku wawonetsanso kuti kuwonetsa kwanthawi yayitali Mlingo wochepa wa ma POP ena kumatha kubweretsa kuperewera kwa chitetezo chamthupi. Kuwona kuchuluka kwa mankhwala ena a POP - okwera kuposa momwe anthu ndi nyama zakuthengo amakumana nawo - kungayambitse kuwonongeka kapena kufa. Maphunziro a Epidemiological okhudzana ndi kuchuluka kwa anthu komanso maphunziro a nyama zakuthengo atha kupereka zambiri zokhudzana ndi thanzi. Komabe, chifukwa maphunziro oterowo samayendetsedwa pang'ono poyerekeza ndi maphunziro a labotale, kupsinjika kwina sikunganenedwe kuti ndi chifukwa cha zotsatira zoyipa.
Pamene tikupitiriza kuphunzira za POPs, tiphunzira zambiri za kuopsa kwa ma POPs kwa anthu onse, kuchuluka kwa zamoyo zina (kuphatikizapo anthu) zomwe zimawonekera, ndi zotsatira zotani za POP pa zamoyozi ndi chilengedwe chawo. EPA idapanga lipoti lofotokozera mwachidule sayansi pa POPs (onani Zothandizira pansipa).
Malo osungira a POPs
Ma POP amatha kuikidwa m'madzi am'madzi ndi m'madzi am'madzi kudzera m'madzi otayira, kuyika mumlengalenga, kuthamanga, ndi njira zina. Chifukwa ma POPs ali ndi kusungunuka kwamadzi pang'ono, amalumikizana kwambiri ndi zinthu zam'madzi. Zotsatira zake, matope amatha kukhala ngati nkhokwe kapena "sink" za POPs. Akaseweredwa m'matope awa, ma POP amatha kuchotsedwa kuti asayendetse kwa nthawi yayitali. Zikasokonezedwa, zitha kubwezeretsedwanso m'dongosolo lazachilengedwe komanso chakudya, zomwe zitha kukhala gwero la kuipitsidwa kwanuko, ngakhalenso padziko lonse lapansi.
SINOYQX yotchulidwa kuchokera Zowonongeka Zosalekeza Zachilengedwe: Nkhani Yapadziko Lonse, Yankho Lapadziko Lonse | US EPA