Lolu cwaningo luhlole ubungozi, ubungozi obuncane, kanye nobuthi bezinto zokuhwebai-cypermethrinukwakheka kwama-tadpole e-anuran. Ekuhlolweni okuphuthumayo, ukugxila okungu-100–800 μg/L kwahlolwa amahora angama-96. Ekuhlolweni okungapheli, ukugxila kwe-cypermethrin okwenzeka ngokwemvelo (1, 3, 6, kanye no-20 μg/L) kwahlolwa ukufa, kwalandelwa ukuhlolwa kwe-micronucleus kanye nokukhubazeka kwe-nuclear cell blood blood izinsuku eziyi-7. I-LC50 yokwakheka kwe-cypermethrin yokuhweba kuma-tadpoles yayingu-273.41 μg L−1. Ekuhlolweni okungapheli, ukugxila okuphezulu kakhulu (20 μg L−1) kwaholela ekufeni okungaphezu kuka-50%, njengoba kwabulala ingxenye yama-tadpoles ahlolwe. Ukuhlolwa kwe-micronucleus kubonise imiphumela ebalulekile ku-6 no-20 μg L−1 futhi kwatholakala ukukhubazeka okuningana kwe-nuclear, okubonisa ukuthi ukwakheka kwe-cypermethrin yokuhweba kunamandla okubulala i-genotoxic ngokumelene ne-P. gracilis. I-Cypermethrin iyingozi enkulu kulolu hlobo, okubonisa ukuthi ingabangela izinkinga eziningi futhi ithinte ukuguquguquka kwalolu hlobo lwemvelo esikhathini esifushane neside. Ngakho-ke, kungaphethwa ngokuthi amafomula e-cypermethrin athengiswayo anemiphumela enobuthi ku-P. gracilis.
Ngenxa yokwanda okuqhubekayo kwemisebenzi yezolimo kanye nokusetshenziswa okujulile kweukulawulwa kwezinambuzaneIzinyathelo, izilwane zasemanzini zivame ukuchayeka ezibulala-zinambuzane1,2. Ukungcoliswa kwemithombo yamanzi eduze kwamasimu ezolimo kungathinta intuthuko kanye nokusinda kwezinto eziphilayo ezingezona ezihlosiwe njengezilwane eziphila emanzini nasemanzini.
Izilwane eziphila emanzini nasemhlabeni ziya ngokuya zibaluleke kakhulu ekuhlolweni kwezibalo zemvelo. Ama-Anuran abhekwa njengezinkomba ezinhle zezinto eziphilayo zokungcola kwemvelo ngenxa yezici zawo ezihlukile njengemijikelezo yokuphila eyinkimbinkimbi, amazinga okukhula okusheshayo kwama-larva, isimo se-trophic, isikhumba esingena emanzini10,11, ukuncika emanzini ukuze azale12 kanye namaqanda angavikelwe11,13,14. Ixoxo elincane lamanzi (i-Physalaemus gracilis), elaziwa kakhulu ngokuthi ixoxo elikhalayo, liboniswe njengohlobo lwezinto eziphilayo zokungcola kwezibulala-zinambuzane4,5,6,7,15. Lolu hlobo lutholakala emanzini amile, ezindaweni ezivikelwe noma ezindaweni ezinendawo yokuhlala ehlukahlukene e-Argentina, e-Uruguay, e-Paraguay nase-Brazil1617 futhi libhekwa njengelizinzile ngokwesigaba se-IUCN ngenxa yokusabalala kwalo okubanzi kanye nokubekezelela izindawo zokuhlala ezahlukene18.
Imiphumela engaphansi kweyokubulala ibikwe ezilwanyaneni eziphila emanzini ngemuva kokuchayeka ku-cypermethrin, okuhlanganisa izinguquko zokuziphatha, zesimo somzimba kanye nezamakhemikhali ezinhlotsheni ezinamathambo ezimpukane23,24,25, ukufa okushintshile kanye nesikhathi sokuguquka kwesimo, izinguquko ze-enzyme, ukwehla kwempumelelo yokuchamisela24,25, ukusebenza ngokweqile26, ukuvinjelwa komsebenzi we-cholinesterase27 kanye nezinguquko ekusebenzeni kokubhukuda7,28. Kodwa-ke, izifundo zemiphumela ye-genotoxic ye-cypermethrin ezilwanyaneni zilinganiselwe. Ngakho-ke, kubalulekile ukuhlola ukuthambekela kwezinhlobo ze-anuran ku-cypermethrin.
Ukungcola kwemvelo kuthinta ukukhula okuvamile kanye nokuthuthukiswa kwezilwane eziphila emanzini nasemanzini, kodwa umphumela omubi kakhulu ukulimala kwezakhi zofuzo ku-DNA okubangelwa ukuchayeka ezibulala-zinambuzane13. Ukuhlaziywa kwesimo seseli legazi kuyisibonakaliso esibalulekile sokungcola kanye nobuthi obungaba khona bento ezinhlotsheni zasendle29. Ukuhlolwa kwe-micronucleus kungenye yezindlela ezisetshenziswa kakhulu ekunqumeni ubuthi be-genotoxicity bamakhemikhali emvelweni30. Kuyindlela esheshayo, ephumelelayo futhi engabizi kakhulu eyisibonakaliso esihle sokungcoliswa kwamakhemikhali kwezinto eziphilayo ezifana nezilwane eziphila emanzini nasemanzini31,32 futhi inganikeza ulwazi ngokuchayeka ezingcoleni ze-genotoxic33.
Inhloso yalolu cwaningo kwakuwukuhlola amandla anobuthi e-cypermethrin yokuhweba ezilwaneni ezincane zasemanzini kusetshenziswa ukuhlolwa kwe-micronucleus kanye nokuhlolwa kwengozi yezemvelo.
Ukufa okuhlanganisiwe (%) kwama-tadpole e-P. gracilis atholakale ekugxilweni okuhlukene kwe-cypermethrin yezentengiselwano ngesikhathi sokuhlolwa okuphuthumayo.
Ukufa okuhlanganisiwe (%) kwama-tadpole e-P. gracilis atholakale ekugxilweni okuhlukene kwe-cypermethrin yokuhweba ngesikhathi sokuhlolwa okungapheli.
Ukufa okuphezulu okubonwe kwaba umphumela wemiphumela yobuthi be-genotoxic kuma-amphibians abhekene nokugxila okuhlukene kwe-cypermethrin (6 no-20 μg/L), njengoba kufakazelwa ukuba khona kwe-micronuclei (MN) kanye nokukhubazeka kwe-nuclear kuma-erythrocyte. Ukwakheka kwe-MN kubonisa amaphutha ku-mitosis futhi kuhlotshaniswa nokubopha okungekuhle kwama-chromosome kuma-microtubules, amaphutha kuma-protein complexes abangela ukumuncwa nokuthuthwa kwama-chromosome, amaphutha ekuhlukanisweni kwama-chromosome kanye namaphutha ekulungisweni komonakalo we-DNA38,39 futhi kungase kuhlotshaniswe nokucindezeleka kwe-oxidative okubangelwa izibulala-zinambuzane40,41. Okunye ukukhubazeka kwabonwa kuzo zonke izingqimba ezihlolwe. Ukwanda kwezingqimba ze-cypermethrin kwandise ukukhubazeka kwe-nuclear kuma-erythrocyte ngo-5% no-20% kumanani aphansi kakhulu (1 μg/L) kanye namanani aphezulu kakhulu (20 μg/L), ngokulandelana. Isibonelo, izinguquko ku-DNA yohlobo zingaba nemiphumela emibi kokubili ekusindeni kwesikhathi esifushane nesikhathi eside, okuholela ekunciphiseni inani labantu, ukuqina kokuzala okushintshile, ukuzalana kwezilwane ezizalwa ndawonye, ukulahlekelwa ukuhlukahluka kwezakhi zofuzo, kanye namazinga okufuduka ashintshiwe. Zonke lezi zici zingathinta ukusinda nokugcinwa kwezinhlobo42,43. Ukwakheka kokukhubazeka kwe-erythroid kungabonisa ukuvinjelwa kwe-cytokinesis, okuholela ekuhlukanisweni kwamaseli okungajwayelekile (ama-erythrocyte e-binucleated)44,45; ama-nuclei ane-multilobed ayizinhlayiya ze-membrane yenuzi enama-lobes amaningi46, kanti ezinye izinkinga ze-erythroid zingase zihlotshaniswe nokwandiswa kwe-DNA, njengezinso/ama-blebs enuzi47. Ukuba khona kwama-erythrocyte ane-anucleated kungabonisa ukuthuthwa komoya-mpilo okuphazamisekile, ikakhulukazi emanzini angcolile48,49. I-Apoptosis ikhombisa ukufa kwamaseli50.
Ezinye izifundo zibonise nemiphumela yobuthi be-cypermethrin. UKabaña nabanye.51 babonise ukuba khona kwezinguquko ze-micronuclei kanye ne-nuclear ezifana namaseli e-binucleated kanye namaseli e-apoptotic kumaseli e-Odontophrynus americanus ngemuva kokuchayeka ekugxilweni okuphezulu kwe-cypermethrin (5000 kanye no-10,000 μg L−1) amahora angama-96. I-apoptosis ebangelwa yi-Cypermethrin nayo yatholakala ku-P. biligonigerus52 kanye ne-Rhinella arenarum53. Le miphumela iphakamisa ukuthi i-cypermethrin inemiphumela yobuthi be-geno ezinhlobonhlobo zezinto eziphilayo zasemanzini nokuthi ukuhlolwa kwe-MN kanye ne-ENA kungaba yinkomba yemiphumela engaphansi kwebulalayo kuma-amphibians futhi kungasebenza ezinhlotsheni zomdabu kanye nezilwane zasendle ezichayeke ezintweni ezinobuthi12.
Izakhi ze-cypermethrin zezentengiselwano zibeka ingozi enkulu emvelweni (kokubili okubukhali nokungalapheki), kanti ama-HQ adlula izinga le-US Environmental Protection Agency (EPA)54 elingathinta kabi uhlobo uma lukhona emvelweni. Ekuhlolweni kwengozi engapheli, i-NOEC yokufa yayingu-3 μg L−1, okuqinisekisa ukuthi amazinga atholakala emanzini angaba yingozi kuhlobo55. I-NOEC ebulalayo yezibungu ze-R. arenarum ezivezwe engxubeni ye-endosulfan ne-cypermethrin yayingu-500 μg L−1 ngemva kwamahora angu-168; leli nani lehle laya ku-0.0005 μg L−1 ngemva kwamahora angu-336. Abalobi babonisa ukuthi uma ukuvezwa isikhathi eside, amazinga aphansi ayingozi kohlobo. Kubalulekile futhi ukugqamisa ukuthi amanani e-NOEC ayephezulu kunalawo e-P. gracilis ngesikhathi esifanayo sokuvezwa, okubonisa ukuthi impendulo yohlobo ku-cypermethrin iqondene nohlobo. Ngaphezu kwalokho, maqondana nokufa, inani le-CHQ le-P. gracilis ngemva kokuchayeka ku-cypermethrin lifinyelele ku-64.67, okuphakeme kunenani elibhekiselwe elibekwe yi-US Environmental Protection Agency54, kanti inani le-CHQ le-R. arenarum larvae nalo laliphakeme kunaleli nani (CHQ > 388.00 ngemva kwamahora angu-336), okubonisa ukuthi izibulala-zinambuzane ezifundwe zibeka ingozi enkulu ezinhlotsheni eziningana zama-amphibian. Uma sibheka ukuthi i-P. gracilis idinga cishe izinsuku ezingu-30 ukuze iqedele ukuguqulwa kwesimo sayo56, kungaphethwa ngokuthi amazinga afundwe e-cypermethrin angase abe nomthelela ekwehleni kwenani labantu ngokuvimbela abantu abangenwe yileli gciwane ukuthi bangene esigabeni sobudala noma sokuzala besebancane.
Ekuhlolweni kwengozi ebaliwe ye-micronuclei kanye nezinye izinkinga ze-erythrocyte nuclear, amanani e-CHQ asukela ku-14.92 kuya ku-97.00, okubonisa ukuthi i-cypermethrin yayinengozi engaba khona ye-genotoxic ku-P. gracilis ngisho nasendaweni yayo yemvelo yokuhlala. Uma kucatshangelwa ukufa, ukugcwala okuphezulu kwamakhemikhali e-xenobiotic abekezelelwa yi-P. gracilis kwakungu-4.24 μg L−1. Kodwa-ke, ukugcwala okuphansi njengo-1 μg/L nakho kubonise imiphumela ye-genotoxic. Leli qiniso lingaholela ekwandeni kwenani labantu abangajwayelekile57 futhi lithinte intuthuko kanye nokuzala kwezinhlobo ezindaweni zazo zokuhlala, okuholela ekwehleni kwenani lezilwane eziphila emanzini.
Izakhi zokwenziwa ze-cypermethrin yesibulala-zinambuzane ezithengiswayo zibonise ubuthi obuphezulu obubukhali nobuhlala isikhathi eside ku-P. gracilis. Amanani aphezulu okufa abonwe, cishe ngenxa yemiphumela enobuthi, njengoba kufakazelwa ukuba khona kwe-micronuclei kanye ne-erythrocyte nuclear disorders, ikakhulukazi i-serrated nuclei, i-lobed nuclei, kanye ne-vesicular nuclei. Ngaphezu kwalokho, izinhlobo ezifundwe zibonise ukwanda kwezingozi zemvelo, kokubili ezibukhali nezingamahlala isikhathi eside. Le datha, ehlanganiswe nezifundo zangaphambilini zeqembu lethu locwaningo, ibonise ukuthi ngisho nezakhi zokwenziwa ze-cypermethrin ezithengiswayo ezahlukene zisabangela ukwehla kwemisebenzi ye-acetylcholinesterase (AChE) kanye ne-butyrylcholinesterase (BChE) kanye nokucindezeleka kwe-oxidative58, futhi kwaholela ezinguqukweni emsebenzini wokubhukuda kanye nokukhubazeka komlomo59 ku-P. gracilis, okubonisa ukuthi izakhi zokwenziwa ze-cypermethrin ezithengiswayo zinobuthi obuphezulu obubulalayo nobungaphansi kwalolu hlobo. UHartmann et al. 60 bathole ukuthi amafomula e-cypermethrin athengiswayo ayenobuthi kakhulu ku-P. gracilis kanye nolunye uhlobo lohlobo olufanayo (i-P. cuvieri) uma kuqhathaniswa nezinye izibulala-zinambuzane eziyisishiyagalolunye. Lokhu kusikisela ukuthi amazinga e-cypermethrin avunyelwe ngokomthetho ukuvikela imvelo angabangela ukufa okuphezulu kanye nokwehla kwenani labantu isikhathi eside.
Kudingeka izifundo ezengeziwe ukuze kuhlolwe ubuthi besibulala-zinambuzane eziphila emanzini nasemanzini, njengoba amazinga atholakala emvelweni angabangela ukufa okuphezulu futhi abe yingozi engaba khona ku-P. gracilis. Ucwaningo ngezinhlobo zezilwane eziphila emanzini nasemanzini kufanele lukhuthazwe, njengoba idatha ngalezi zinto eziphilayo incane, ikakhulukazi ezinhlotsheni zaseBrazil.
Ukuhlolwa kobuthi obungapheli kwathatha amahora angu-168 (izinsuku ezingu-7) ngaphansi kwezimo ezimile futhi amazinga angaphansi kokubulala ayengu: 1, 3, 6 kanye no-20 μg ai L−1. Kuzo zombili izivivinyo, ama-tadpole ayi-10 ngeqembu lokwelashwa ahlolwe ngamakhophi ayisithupha, okwaba ama-tadpole angama-60 ngokuhlushwa ngakunye. Phakathi naleso sikhathi, ukwelashwa kwamanzi kuphela kwasebenza njengokulawula okungekuhle. Ukusetha ngakunye kokuhlola kwakuhlanganisa isitsha sengilazi esingenasici esinomthamo wama-500 ml kanye nobuningi be-tadpole eyodwa kuma-50 ml esisombululo. Iflaski yayimbozwe ngefilimu ye-polyethylene ukuvimbela ukuhwamuka futhi yayivuthwa njalo.
Amanzi ahlaziywe ngamakhemikhali ukuze kutholakale amazinga ezibulala-zinambuzane emahoreni angu-0, 96, kanye namahora angu-168. Ngokusho kukaSabin et al. 68 noMartins et al. 69, ukuhlaziywa kwenziwe e-Pesticide Analysis Laboratory (LARP) ye-Federal University yaseSanta Maria kusetshenziswa i-gas chromatography ehlanganiswe ne-triple quadrupole mass spectrometry (i-Varian model 1200, ePalo Alto, eCalifornia, e-USA). Ukunqunywa kwenani lezibulala-zinambuzane emanzini kuboniswa njengezinto ezengeziwe (Ithebula SM1).
Ekuhlolweni kwe-micronucleus (MNT) kanye nokuhlolwa kwe-nuclear abnormality test (RNA) ngamangqamuzana abomvu, kwahlaziywa ama-tadpoles angu-15 eqenjini ngalinye lokwelashwa. Ama-tadpoles ahlanzwa nge-5% lidocaine (50 mg g-170) futhi amasampula egazi aqoqwa ngokubhoboza inhliziyo kusetshenziswa izinaliti ezilahlwayo ezisebenzisa i-heparin. Ama-smear egazi alungiswa kuma-slides e-microscope angenamagciwane, omiswa emoyeni, aqiniswa nge-100% methanol (4 °C) imizuzu emi-2, bese egcotshwa ngesisombululo se-10% Giemsa imizuzu eyi-15 ebumnyameni. Ekupheleni kwenqubo, ama-slides ahlanzwa ngamanzi acwengekile ukuze kususwe amabala amaningi futhi omiswe ekushiseni kwegumbi.
Okungenani ama-RBC ayi-1000 avela ku-tadpole ngayinye ahlaziywe kusetshenziswa i-microscope engu-100× enenhloso engu-71 ukuthola ukuthi kukhona i-MN kanye ne-ENA. Ama-RBC angu-75,796 avela ku-tadpole ahlolwe ngokubheka amazinga kanye nokulawula kwe-cypermethrin. Ubuthi be-genotoxicity buhlaziywe ngokwendlela kaCarrasco et al. noFenech et al.38,72 ngokunquma imvamisa yezilonda ze-nuclear ezilandelayo: (1) amaseli e-anucleate: amaseli angenawo ama-nuclei; (2) amaseli e-apoptotic: ukuqhekeka kwe-nuclei, ukufa kweseli okuhleliwe; (3) amaseli e-binucleate: amaseli anama-nuclei amabili; (4) ama-bud e-nuclei noma amaseli e-bleb: amaseli anama-nuclei anezinhlayiya ezincane ze-membrane ye-nuclei, ama-blebs afana ngobukhulu ne-micronuclei; (5) amaseli e-karyolyzed: amaseli anohlaka lwe-nucleus kuphela ngaphandle kwezinto zangaphakathi; (6) amaseli ane-notched: amaseli anama-nuclei anemifantu esobala noma ama-notch ngesimo sawo, abizwa nangokuthi ama-nuclei anesimo sezinso; (7) amaseli akhiwe ngama-lobed: amaseli anezinhlayiya zenuzi ezinkulu kunezinhlayiya ezishiwo ngenhla; kanye (8) amaseli amancane: amaseli ane-nuclei egobile kanye ne-cytoplasm encishisiwe. Izinguquko ziqhathaniswa nemiphumela yokulawula engemihle.
Imiphumela yokuhlolwa kobuthi obukhulu (LC50) ihlaziywe kusetshenziswa isofthiwe ye-GBasic kanye nendlela ye-TSK-Trimmed Spearman-Karber74. Idatha yokuhlolwa okungapheli ihlolwe kusengaphambili ukuze kutholakale ukuthi amaphutha ajwayelekile (i-Shapiro-Wilks) kanye ne-homogeneity of variance (i-Bartlett). Imiphumela ihlaziywe kusetshenziswa ukuhlaziywa kobuguquguquki obungaqondile (i-ANOVA). Ukuhlolwa kukaTukey kusetshenziswe ukuqhathanisa idatha phakathi kwabo, kanti ukuhlolwa kukaDunnett kusetshenziswe ukuqhathanisa idatha phakathi kweqembu lokwelashwa neqembu lokulawula elingekuhle.
Idatha ye-LOEC kanye ne-NOEC ihlaziywe kusetshenziswa isivivinyo sikaDunnett. Ukuhlolwa kwezibalo kwenziwe kusetshenziswa isofthiwe ye-Statistica 8.0 (StatSoft) enezinga lokubaluleka elingu-95% (p < 0.05).
Isikhathi sokuthunyelwe: Mashi-13-2025