Illar gurbataccen mai ga kifi a ruwa

An lura da gubar gurbataccen mai ga kifin ruwa daga malalar mai kamar bala'in Exxon Valdez, da kuma daga maɓuɓɓugar da ba su da tushe, kamar zubar da ruwa, wanda shi ne mafi girma tushen gurɓatar mai a cikin ruwan teku.

Illar gurbataccen mai ga kifi a ruwa

Danyen mai yana shiga magudanar ruwa daga zubewa ko zubar da ruwa ya ƙunshi polycyclic aromatic hydrocarbons (PAHs), mafi yawan abubuwan da ke cikin mai. Hanyar shan PAH cikin kifi ya dogara da yawancin abubuwan muhalli da kaddarorin PAH. Hanyoyi na gama gari sune ciki, samun iska na gills, da ɗaukar fata. Kifin da aka fallasa wa waɗannan PAHs yana nuna nau'ikan sakamako masu guba ciki har da lalata kwayoyin halitta, nakasasshen tsarin halittar jiki, canjin girma da haɓakawa, rage girman jiki, hana damar yin iyo da mace-mace . [1] [2] [3] Nakasar dabi'a ta bayyanar PAH, irin su fin da muƙamuƙi na muƙamuƙi, Kuma suna haifar da raguwar rayuwa a cikin kifaye sosai saboda raguwar iya yin iyo da ciyarwa. [1] Duk da yake ba a san ainihin tsarin guba na PAH ba, akwai hanyoyi guda huɗu da aka tsara. [4] Wahalar gano takamaiman hanyar mai guba ya fi yawa saboda nau'ikan mahaɗan PAH iri-iri tare da kaddarorin daban-daban. [4]

 
Hoto na kusa na Kemp's Ridley Turtle da aka gurbata cikin mai a ranar 1 ga Yuni, 2010.

An fara bincike kan tasirin muhallin da masana'antar man fetur ke da shi, a tsakiyar karni zuwa karshen karni na 20, yayin da masana'antar mai ta bunkasa da fadada. [5] Babban jigilar danyen mai ya karu a sakamakon karuwar bukatar mai a duniya, wanda daga baya ya kara yawan malalar mai. [5] Zubewar mai ta ba da damammaki ga masana kimiyya don nazarin illolin da ɗanyen mai ke haifarwa ga muhallin ruwa, da ƙoƙarin haɗin gwiwa tsakanin Hukumar Kula da Tekun Ruwa da Yanayin Sama (NOAA) da Hukumar Tsaron Tekun Amurka ta haifar da ingantacciyar ƙoƙarin mayar da martani da cikakken bincike kan mai. illar gurbacewa. [5] Zubewar mai na Exxon Valdez a shekarar 1989, da kuma malalar mai ta Deepwater Horizon a shekarar 2010, dukkansu sun haifar da karuwar ilimin kimiyya kan takamaiman illar gurbacewar mai ga kifin ruwa.

Exxon Valdez mai ya zube

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Binciken da aka mayar da hankali kan gurbacewar mai ga kifaye ya fara da gaske a cikin shekarata 1989, bayan da jirgin ruwa na Exxon Valdez ya bugi wani ruwa a cikin Prince William Sound, Alaska kuma ya zubar da kusan galan miliyan 11 na danyen mai a cikin ruwan da ke kewaye. [6] A lokacin, malalar mai na Exxon Valdez ita ce mafi girma a tarihin Amurka. [6] Akwai illoli da yawa da malalar ta haifar ciki har da asarar biliyoyin herring na Pacific da ƙwai mai ruwan hoda . [5] Dabbobin tekun Pacific ya fara haifuwa a ƙarshen Maris lokacin da malalar ta faru, wanda ya haifar da kusan rabin ƙwai na jama'a da aka fallasa ga ɗanyen mai. Pacific herring spawn a cikin intertidal da subtidal zones, sa da m qwai cikin sauƙi fallasa ga gurɓata. [1]

 
Sakamakon malalar mai a Deepwater Horizon a Tekun Mexico.

Deepwater Horizon mai zubewa

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Bayan 20 ga Afrilu, shekarata 2010, lokacin da fashewa a kan dandalin hako mai na Deepwater Horizon Macondo ya haifar da malalar mai mafi girma a tarihin Amurka, an gabatar da wata dama ta bincike game da gubar mai. [7] Kimanin galan miliyan kusan 171 na danyen mai ya kwarara daga tekun teku zuwa Tekun Mexico, wanda ya fallasa yawancin halittun da ke kewaye da su . [7] Zubewar mai na Deepwater Horizon shima ya zo daidai da taga mai haɗe-haɗe na nau'ikan kifaye daban-daban na muhalli da kasuwanci, gami da yellowfin da tuna bluefin Atlantic. [8] Zubewar mai ta shafi tuna tuna bluefin Atlantika kai tsaye, saboda kusan kashi 12% na tsutsa tuna suna cikin ruwa mai gurbataccen ruwa, [9] kuma Gulf of Mexico shine kawai sanannen wuraren haifuwa ga yawan yammacin tuna bluefin. [7]

 
Wani ruɓaɓɓen kifi da ya makale a cikin mai a cikin Bay of Isles, Alaska bayan malalar mai na Exxon Valdez.

Fuskantar mai

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Zubewar mai, da kuma kwararar mai a kullum daga yankunan birane, na iya haifar da polycyclic aromatic hydrocarbon (PAHs) shiga yanayin yanayin ruwa. Da zarar PAHs sun shiga cikin yanayin ruwa, ana iya fallasa kifaye zuwa gare su ta hanyar sha, samun iska na gills, da kuma ɗaukar dermal. [10] Babban hanyar da za a ɗauka zai dogara ne akan halayen nau'in kifaye da kayan aikin sinadarai na PAH na damuwa. Mazauni na iya zama babban abin yanke shawarar hanyar fallasa. Alal misali, kifayen da ke cinye kifin demersal suna da yuwuwar shigar da PAHs waɗanda suka ɓata zuwa laka, yayin da kifayen da ke iyo a saman suna cikin haɗari mafi girma don bayyanar dermal. Bayan saduwa da PAH, bioavailability zai shafi yadda ake ɗaukar PAH a hankali. Sanna Kuma EPA tana gano manyan PAHs 16 masu damuwa kuma kowane ɗayan waɗannan PAHs yana da madaidaicin digiri na bioavailability. Alal misali, PAHs masu ƙananan nauyin kwayoyin halitta sun fi samuwa saboda suna narkar da su cikin ruwa kuma don haka sun fi samuwa ga kifi a cikin ruwa. Kuma Hakazalika, PAHs na hydrophilic sun fi samuwa don ɗaukar kifi. Kuma A saboda wannan dalili, yin amfani da masu rarraba mai, kamar Corexit, don magance zubar da man fetur na iya ƙara yawan PAHs ta hanyar ƙara yawan solubility a cikin ruwa da kuma sa su zama masu samuwa don ɗauka ta hanyar gills. [10] Da zarar an ɗauki PAH, haɓakar kifin na iya rinjayar tsawon lokaci da ƙarfin bayyanar da kyallen takarda. Kifi suna iya saurin daidaita kashi kusan 99% na PAHs zuwa ƙarin hydrophilic metabolite ta tsarin hanta-biliary. [10] Wannan yana ba da damar fitar da PAHs. Adadin metabolism na PAHs zai dogara ne akan jima'i da girman nau'in. Ƙarfin haɓaka PAHs zuwa ƙarin nau'i na hydrophilic zai iya hana haɓakar ƙwayoyin cuta da dakatar da PAHs daga watsawa ga kwayoyin halitta suna haɓaka gidan yanar gizon abinci. Domin mai zai iya dawwama a cikin muhalli tsawon lokaci bayan malalar mai ta hanyar lalata, ana iya ci gaba da fallasa kifin demersal ga PAHs shekaru da yawa bayan malalar mai. An tabbatar da wannan ta hanyar kallon biliary PAH metabolites na kifin da ke zaune a ƙasa. Misali, kifayen da ke zaune a kasa har yanzu sun nuna madaidaicin matakan ƙananan nauyin kwayoyin halitta na PAH metabolites shekaru a ƙalla 10 bayan malalar mai na Exxon Valdez . [10]

Abubuwan danyen mai

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Danyen mai yana kunshe da mahadi sama da 17,000. [11] Daga cikin wadannan mahadi guda 17,000 akwai PAHs, wadanda ake la'akari da mafi yawan abubuwa masu guba na mai. [10] PAHs an kafa su ta hanyar tsarin pyrogenic da petrogen. Petrogenic PAHs ana samun su ta hanyar haɓakar matsi na kayan halitta. Sabanin haka, PAHs na pyrogenic suna samuwa ta hanyar konewar abubuwan da ba su cika ba. Danyen mai a zahiri ya ƙunshi PAHs petrogen kuma waɗannan matakan PAH suna ƙaruwa sosai ta hanyar ƙona mai wanda ke haifar da PAHs pyrogenic. Matsayin PAHs da aka samu a cikin ɗanyen mai ya bambanta da nau'in ɗanyen mai. Misali, danyen mai daga Exxon Valdez mai zubewa yana da adadin PAH na 1.47%, yayin da adadin PAH daga Tekun Arewa yana da ƙarancin PAH na 0.83%. [10]

Tushen gurbatar danyen mai

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Rashin gurɓataccen mai a cikin yanayin yanayin ruwa na iya haifar da pyrogenic da PAHs na petrogenic shiga cikinn dukkan waɗannan yanayin. Petrogenic PAHs na iya shiga cikin magudanar ruwa ta hanyar mai, manyan malalar mai, magudanar ruwa da malalar mai daga yankunan birane. [12] Madogaran Pyrogenic PAH sun ƙunshi roba soot taya na dizal da ƙurar kwal. [13] Ko da yake akwai tushen dabi'a na PAHs kamar ayyukan volcanic da ɓarkewar ajiyar kwal, tushen ɗan adam yana haifar da mafi mahimmancin shigar da PAHs cikin yanayi. [12] Waɗannan tushen ɗan adam sun haɗa da dumama mazaunin gida, samar da kwalta, iskar gas, da amfani da man fetur. [12] Rashin gurɓataccen mai na PAH ya fi zama ruwan dare daga zubewar ɗanyen mai irin su Exxon Valdez, ko tsintsayen mai; duk da haka, tare da raguwar pyrogenic PAHs kuma na iya zama babba. Ko da yake manyan zubewar mai irin su Exxon Valdez na iya gabatar da wani adadi mai yawa na ɗanyen mai zuwa wani yanki a cikin ɗan gajeren lokaci, zubar da ruwa na yau da kullun ya ƙunshi mafi yawan gurɓataccen mai ga yanayin ruwa. Sannan Kuma Zubar da yanayin yanayi kuma na iya zama tushen PAHs cikin yanayin yanayin ruwa. Zubar da PAHs daga yanayi zuwa cikin ruwa yana tasiri sosai ta hanyar rabon gas-barbashi na PAH. [12]

 
An kama Pelicans Brown mai nauyi a Grand Isle, Louisiana

An lura da yawancin tasirin bayyanar PAH a cikin kifin ruwa. Musamman, an gudanar da bincike akan kifin amfrayo da tsutsa, haɓakar kifin da aka fallasa ga PAHs, da ɗaukar PAH ta kifin ta hanyoyi daban-daban na fallasa. Ɗaya (1) daga cikin binciken ya gano cewa ƙwai na Pacific herring da aka fallasa ga yanayin da ke kwaikwayon "Exxon Valdez" mai ya haifar da ƙyanƙyashe ƙwai, rage girman girman kifin da balagagge da kuma tasirin teratogenic, ciki har da kwarangwal, zuciya da jijiyoyin jini, fin da kuma yolk sac malformations. [1] Edema jakar gwaiduwa ce ke da alhakin yawancin mace-macen tsutsa na herring. [1] An lura da lalacewar teratogenic a cikin ƙwanƙwasa dorsal da kashin baya, da kuma a cikin muƙamuƙi don rage rayuwar kifaye masu tasowa yadda ya kamata, sannan kuma ta hanyar rashin iya yin iyo da kuma ciyarwa bi da bi. Ciyarwa da nisantar ganima ta hanyar ninkaya suna da mahimmanci ga rayuwar tsutsa da kifayen yara. [1] Duk abubuwan da aka gani a cikin ƙwai na herring a cikin binciken sun yi daidai da tasirin da aka gani a cikin kwai kifin da aka fallasa sakamakon zubewar mai na Exxon Valdez . [1] An yi la'akari da embryos na Zebrafish da aka fallasa ga mai suna da mummunar lahani na teratogenic kamar waɗanda aka gani a cikin embryos na herring, ciki har da edema, rashin aikin zuciya, da zubar da jini na ciki. [3] A cikin wani binciken da aka mayar da hankali kan ɗaukar PAHs ta kifaye, embryos na salmon an fallasa su ga ɗanyen mai a cikin yanayi daban-daban guda uku, ciki har da ta hanyar zubar da ruwa mai rufin mai. [2] Matsakaicin PAH a cikin embryos kai tsaye da aka fallasa ga mai da waɗanda aka fallasa su da fitar da ruwa na PAH ba su da bambanci sosai. An lura da bayyanar PAH don haifar da mutuwa, ko da lokacin da PAHs suka fallasa zuwa kifi ta hanyar ruwa. Daga sakamakon, an ƙaddara cewa embryos kifaye kusa da Exxon Valdez ya zube a cikin Yarima William Sound waɗanda ba su da alaƙa da mai kai tsaye har yanzu suna iya tara matakan mutuwa na PAHs. [2] Yayin da yawancin gwaje-gwajen gwaje-gwaje da na halitta sun lura da wasu mummunar tasirin PAH ga kifi, an kuma lura da rashin tasiri ga wasu mahadi na PAH, wanda zai iya zama saboda rashin haɓaka yayin da ake nunawa ga fili. [3]

Tsarin tsari na aikin mai guba

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Duk da yake an tabbatar da cewa nau'o'in PAH daban-daban suna aiki ta hanyoyi daban-daban masu guba saboda bambancin nauyin kwayoyin su, shirye-shiryen zobe, da kaddarorin ruwa, sannan Kuma takamaiman hanyoyin PAH mai guba ga kifaye da ci gaban kifi har yanzu ba a san su ba. [3] Guba ya dogara da gwargwadon irin sinadari da ke cikin mai zai haɗu da ruwa: ana kiran wannan a matsayin juzu'in ruwan da ke da alaƙa da mai. Hanyoyin da aka tsara na masu guba na PAHs sune guba ta hanyar narcosis, hulɗa tare da hanyar AhR, alkyl phenanthrene toxicity, da ƙari mai guba ta hanyoyi masu yawa. [4]

  • Samfurin narcosis bai iya yin hasashen daidai sakamakon tasirin PAH na fallasa herring da salmon ruwan hoda ba, a cewar wani bincike. [4]
  • An lura da rashin lafiyar farko na waɗannan PAH a cikin embryos na kifi don zama AhR mai zaman kanta, kuma tasirin su na zuciya ba shi da alaƙa da kunna AhR ko Cytochrome P450, iyali 1, memba A cikin endocardium . [3]
  • An yi nazarin ƙirar alkyl phenanthrene ta hanyar fallasa herring da salmon ruwan hoda zuwa gaurayawan PAHs a ƙoƙarce-ƙoƙarce don fahimtar hanyoyin miyagu na PAHs. An samo samfurin gabaɗaya yana tsinkaya sakamakon fallasa mai lalacewa da mutuwa. [4] Danniya na Oxidative da kuma tasiri akan morphogenesis na zuciya da jijiyoyin jini sune hanyoyin da aka tsara don maganin alkyl phenanthrene. [4] Ba a san takamaiman hanyar ba.
  • Tun da PAHs sun ƙunshi bambance-bambance daban-daban na PAHs, ana iya bayyana guba ta hanyar amfani da wasu daga cikin hanyoyin aiki da yawa sosai. [4]

Duba wasu abubuwan

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  • Likitan ruwa na ruwa
  • gurbacewar ruwa
    • tarkacen ruwa

Manazarta

gyara sashe
  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Carls, MG, Rice, SD, Hose, JE. 1999. Sensitivity of fish embryos to weathered crude oil: Part I. Low‐level exposure during incubation causes malformations, genetic damage, and mortality in larval Pacific herring (Clupea pallasi). Environmental Toxicology and Chemistry, 18 (3): 481–493.
  2. 2.0 2.1 2.2 Heintz, RA, Short, JW, Rice, SD. 1999 Sensitivity of fish embryos to weathered crude oil: Part II. Increased mortality of pink salmon (Oncorhynchus gorbuscha) embryos incubating downstream from weathered Exxon Valdez crude oil. Environmental Toxicology and Chemistry, 18 (3): 494–503.
  3. 3.0 3.1 3.2 3.3 3.4 Incardona, JP, Carls, MG, Teroaka, H, Sloan, CA, Collier, TK, Scholz, NL. 2005. Aryl Hydrocarbon Receptor-Independent Toxicity of Weathered Crude Oil during Fish Development. Environmental Health Perspectives, 113 (12): 1755–1762.
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Barron MG, Carls MG, Heintz R, Rice SD. 2003. Evaluation of fish early-life stage toxicity models of chronic embryonic exposures to complex polycyclic aromatic hydrocarbon mixtures. Oxford Journals. 78(1): 60–67.
  5. 5.0 5.1 5.2 5.3 Shigenaka, G. 2014. Twenty-Five Years After the Exxon Valdez Oil Spill: NOAA’s Scientific Support, Monitoring and Research. Seattle: NOAA Office of Response and Restoration.
  6. 6.0 6.1 Skinner, SK, Reilly, WK. 1989. The Exxon Valdez Oil Spill: A Report to the President. United States National Response Team.
  7. 7.0 7.1 7.2 Adams, A. 2015. Summary of Information concerning the Ecological and Economic Impacts of the BP Deepwater Horizon Oil Spill Disaster. National Resource Defense Council. IP:15-04-A
  8. Incardona JP, Gardner LD, Linbo TL, Brown TL, Esbaugh AJ, Mager E, Stieglitz JD, French BL, Labenia JS, Laetz CA, Tagal M, Sloan CA, Elizur A, Benetti DD, Grosell M, Block BA, Scholz NL. 2014. Deepwater Horizon crude oil impacts the developing hearts of large predatory pelagic fish. Proceedings of the National Academy of Sciences of the United States of America, 111(15): 1510–1518.
  9. Muhling, BA, Roffer, MA, Lamkin, JT, Ingram Jr., GW, Upton, MA, Gawlikowski, G, Muller-Karger, F, Habtes, S, Richards, WJ. 2012. Overlap between Atlantic bluefin tuna spawning grounds and observed Deepwater Horizon surface oil in the northern Gulf of Mexico. Marine Pollution Bulletin. 64(4): 679–687.
  10. 10.0 10.1 10.2 10.3 10.4 10.5 Snyder, Susan, Erin Pulster, Dana Wetzel, Steven Murawski. 2015. PAH exposure in Gulf of Mexico demersal fishes, post- deepwater horizon. Environmental Science and Technology 49: 8786–8795.
  11. Pampanin, DM, Sydnes, MO. (2013). Polycyclic Aromatic Hydrocarbons a Constituent of Petroleum: Presence and Influence in the Aquatic Environment, Hydrocarbon, Dr. Vladimir Kutcherov (Ed.), InTech
  12. 12.0 12.1 12.2 12.3 Hussein, Abdel, and Mona Mansour. 2015. A review on polycyclic aromatic hydrocarbons: Source, environmental impact, effect on human health and remediation. Egyptian Journal of Petroleum 25: 107–123
  13. Burgess, RM, Ryba, S, Cantwell, M, Perron, MM, Tien, R, Thibideau, LM. 2001. Bioavailability of PAHs from pyrogenic and petrogenic sources using glass fish. Society of Environmental Toxicology and Chemistry Annual Meeting, Baltimore, MD.