Olu phononongo luvavanye ubungozi, ubukrelekrele, kunye nobutyhefu bezinto zorhweboi-cypermethrinIifomyula kwiintakumba ze-anuran. Kuvavanyo olukhawulezileyo, amazinga e-100–800 μg/L avavanyelwe iiyure ezingama-96. Kuvavanyo olungapheliyo, amazinga e-cypermethrin ayenzeka ngokwendalo (1, 3, 6, kunye nama-20 μg/L) avavanyelwe ukufa, kulandele uvavanyo lwe-micronucleus kunye nokuphazamiseka kwe-nuclear cell blood cell kangangeentsuku ezi-7. I-LC50 yefomyula ye-cypermethrin yorhwebo kwiintakumba yayiyi-273.41 μg L−1. Kuvavanyo olungapheliyo, uxinzelelo oluphezulu (20 μg L−1) lubangele ukufa okungaphezulu kwama-50%, njengoko ibulale isiqingatha sentakumba ezivavanyiweyo. Uvavanyo lwe-micronucleus lubonise iziphumo ezibalulekileyo kwi-6 kunye ne-20 μg L−1 kwaye kwafunyanwa iingxaki ezininzi zenyukliya, nto leyo ebonisa ukuba ifomyula ye-cypermethrin yorhwebo inamandla okubangela ubuthi kwi-P. gracilis. I-Cypermethrin iyingozi kakhulu kolu hlobo, nto leyo ebonisa ukuba inokubangela iingxaki ezininzi kwaye ichaphazele indlela olusebenza ngayo olu hlobo lwendalo kwixesha elifutshane nelide. Ke ngoko, kunokugqitywa kwelokuba iifomyula ze-cypermethrin zorhwebo zinefuthe elibi kwi-P. gracilis.
Ngenxa yokwanda okuqhubekayo kwemisebenzi yezolimo kunye nokusetyenziswa kakhuluabalawuli berhorhoimilinganiselo, izilwanyana zasemanzini zihlala zichaphazeleka zizibulali-zinambuzane1,2. Ungcoliseko lwemithombo yamanzi kufutshane namasimi ezolimo lunokuchaphazela uphuhliso kunye nokusinda kwezinto eziphilayo ezingezizo ezijoliswe kuzo ezifana nezilwanyana ezihlala emanzini nasemanzini.
Izilwanyana eziphila emanzini nasemhlabeni ziya zisiba zibaluleke ngakumbi kuvavanyo lwe-matrices yokusingqongileyo. Ii-Anura zithathwa njengezikhombisi ezilungileyo zezinto eziphilayo ezingcolisa indalo ngenxa yeempawu zazo ezizodwa ezifana nemijikelo yobomi enzima, amazinga okukhula ngokukhawuleza kwee-larval, imeko ye-trophic, ulusu olungena emanzini10,11, ukuxhomekeka emanzini ukuze azale12 kunye namaqanda angakhuselekanga11,13,14. Ixoxo elincinci lamanzi (iPhysalaemus gracilis), elaziwa kakhulu ngokuba yi-weeping frog, libonakaliswe njengohlobo lwe-bioindicator longcoliseko lwezinambuzane4,5,6,7,15. Olu hlobo lufumaneka emanzini amileyo, kwiindawo ezikhuselweyo okanye kwiindawo ezinendawo yokuhlala eyahlukileyo eArgentina, eUruguay, eParaguay naseBrazil1617 kwaye lithathwa lizinzile kudidi lwe-IUCN ngenxa yokusasazwa kwalo ngokubanzi kunye nokunyamezela iindawo zokuhlala ezahlukeneyo18.
Iziphumo ezingaphantsi kokubulala ziye zaxelwa kwizilwanyana ezihlala emanzini emva kokuchatshazelwa yi-cypermethrin, kubandakanya utshintsho lokuziphatha, imo kunye ne-biochemical kwi-tadpoles23,24,25, utshintsho lokufa kunye nexesha lokutshintsha kwesimo somzimba, utshintsho lwe-enzyme, impumelelo yokuncipha kokuqandusela24,25, ukusebenza kakhulu26, ukuthintela umsebenzi we-cholinesterase27 kunye notshintsho ekusebenzeni kokudada7,28. Nangona kunjalo, izifundo zeziphumo ze-genotoxic ze-cypermethrin kwizilwanyana ezihlala emanzini zilinganiselwe. Ke ngoko, kubalulekile ukuvavanya ukuba iintlobo ze-anuran zisengozini kangakanani kwi-cypermethrin.
Ungcoliseko lokusingqongileyo luchaphazela ukukhula okuqhelekileyo kunye nophuhliso lwezilwanyana ezihlala emanzini, kodwa isiphumo esibi kakhulu kukonakala kwemfuza kwi-DNA okubangelwa kukuvezwa kwezibulali-zinambuzane13. Uhlalutyo lwemo yeeseli zegazi luphawu olubalulekileyo longcoliseko kunye nobuthi obunokubakho bento kwizilwanyana zasendle29. Uvavanyo lwe-micronucleus yenye yezona ndlela zisetyenziswa kakhulu ekuchongeni ubuthi beekhemikhali kwindalo esingqongileyo30. Yindlela ekhawulezayo, esebenzayo nengabizi kakhulu eyimbonakaliso elungileyo yongcoliseko lweekhemikhali lwezinto eziphilayo ezifana nezilwanyana ezihlala emanzini31,32 kwaye inokubonelela ngolwazi malunga nokuchatshazelwa bungcoliseko lwe-genotoxic33.
Injongo yolu phononongo yayikukuvavanya amandla anobuthi e-cypermethrin yemveliso kwiintakumba ezincinci zasemanzini kusetyenziswa uvavanyo lwe-micronucleus kunye novavanyo lomngcipheko wendalo.
Ukufa okuqokelelweyo (%) kweentakumba ze-P. gracilis ezivezwe kumanqanaba ahlukeneyo e-cypermethrin yorhwebo ngexesha lovavanyo olukhawulezileyo.
Ukufa okuqokelelweyo (%) kweentakumba ze-P. gracilis ezivezwe kumanqanaba ahlukeneyo e-cypermethrin yorhwebo ngexesha lovavanyo olungapheliyo.
Ukufa okuphezulu okubonwayo kube ngumphumo weziphumo ze-genotoxic kwizilwanyana eziphila emanzini ezivezwe kumanqanaba ahlukeneyo e-cypermethrin (6 kunye ne-20 μg/L), njengoko kungqinwa bubukho be-micronuclei (MN) kunye nokuphazamiseka kwenyukliya kwi-erythrocytes. Ukwakheka kwe-MN kubonisa iimpazamo kwi-mitosis kwaye kunxulunyaniswa nokubophelela kakubi kwe-chromosomes kwi-microtubules, iziphene kwi-protein complexes ezinoxanduva lokufunxwa kunye nokuthuthwa kwe-chromosome, iimpazamo ekuhlukanisweni kwe-chromosome kunye neempazamo ekulungisweni komonakalo we-DNA38,39 kwaye zinokunxulunyaniswa noxinzelelo lwe-oxidative olubangelwa zizinambuzane40,41. Ezinye izinto ezingaqhelekanga zibonwe kuzo zonke iindawo ezivavanyiweyo. Ukwanda koxinzelelo lwe-cypermethrin kwandisa ukungasebenzi kakuhle kwenyukliya kwi-erythrocytes nge-5% kunye ne-20% kwimilinganiselo ephantsi (1 μg/L) kunye neyona iphezulu (20 μg/L), ngokulandelelana. Umzekelo, utshintsho kwi-DNA yesilwanyana lunokuba nemiphumo emibi kakhulu kokuphila kwexesha elifutshane nelide, okubangela ukwehla kwabemi, ukuguquka kokufaneleka kokuzala, ukuzalana, ukulahleka kokwahluka kwezakhi zofuzo, kunye namazinga okufuduka atshintshileyo. Zonke ezi zinto zinokuchaphazela ukusinda kunye nokugcinwa kweentlobo42,43. Ukwakheka kwezinto ezingaqhelekanga ze-erythroid kunokubonisa ukuvinjwa kwi-cytokinesis, okubangela ukwahlukana kweeseli okungaqhelekanga (ii-erythrocytes ezine-binucleated)44,45; ii-nuclei ezine-multilobed ziiprotrusions ze-membrane yenyukliya ene-lobes ezininzi46, ngelixa ezinye izinto ezingaqhelekanga ze-erythroid zinokunxulunyaniswa nokwandiswa kwe-DNA, njengezintso zenyukliya/ii-blebs47. Ubukho bee-erythrocytes ezine-anucleated bunokubonisa ukuhanjiswa kweoksijini okungasebenzi kakuhle, ngakumbi emanzini angcolisiweyo48,49. I-Apoptosis ibonisa ukufa kweeseli50.
Ezinye izifundo zikwabonise iziphumo ze-genotoxic ze-cypermethrin. UKabaña et al.51 babonise ubukho be-micronuclei kunye notshintsho lwenyukliya olufana neeseli ze-binucleated kunye neeseli ze-apoptotic kwiiseli ze-Odontophrynus americanus emva kokuvezwa kuxinzelelo oluphezulu lwe-cypermethrin (5000 kunye ne-10,000 μg L−1) kangangeeyure ezingama-96. I-apoptosis ebangelwa yi-Cypermethrin ikwafunyenwe kwi-P. biligonigerus52 kunye ne-Rhinella arenarum53. Ezi ziphumo zibonisa ukuba i-cypermethrin ineziphumo ze-genotoxic kwiintlobo ngeentlobo zezinto eziphilayo zasemanzini kwaye uvavanyo lwe-MN kunye ne-ENA lunokuba luphawu lweziphumo ezingaphantsi kwe-subfal kwizilwanyana zasemanzini kwaye lunokusebenza kwiintlobo zendalo kunye neentlobo zasendle ezivezwa kwi-toxicants12.
Iifomyula zorhwebo ze-cypermethrin zibeka umngcipheko omkhulu kwindalo esingqongileyo (ezibukhali nezingapheliyo), apho ii-HQs zidlula inqanaba le-US Environmental Protection Agency (EPA)54 elinokuchaphazela kakubi uhlobo lwesilwanyana ukuba lukhona kwindalo esingqongileyo. Kuvavanyo lomngcipheko ongapheliyo, i-NOEC yokufa yayiyi-3 μg L−1, iqinisekisa ukuba amazinga afunyenwe emanzini anokuba yingozi kwisilwanyana esiphilayo55. I-NOEC ebulalayo ye-R. arenarum larvae evezwe kumxube we-endosulfan kunye ne-cypermethrin yayiyi-500 μg L−1 emva kweeyure ezili-168; eli xabiso lehle laya kwi-0.0005 μg L−1 emva kweeyure ezingama-336. Ababhali babonisa ukuba okukhona ukuvezwa ixesha elide, kokukhona ukuvezwa okuncinci, kokukhona ukungcola okuyingozi kwisilwanyana esiphilayo kuphantsi. Kubalulekile kwakhona ukugxininisa ukuba amaxabiso e-NOEC ayephezulu kunee-P. gracilis ngexesha elifanayo lokuvezwa, okubonisa ukuba impendulo yesilwanyana kwi-cypermethrin ixhomekeke kwisilwanyana esiphilayo. Ngaphezu koko, ngokubhekiselele ekufeni, ixabiso le-CHQ le-P. gracilis emva kokuvezwa kwi-cypermethrin lifikelele kwi-64.67, elingaphezulu kwexabiso elimiselweyo yi-US Environmental Protection Agency54, kwaye ixabiso le-CHQ le-R. arenarum larvae nalo laliphezulu kuneli xabiso (CHQ > 388.00 emva kweeyure ezingama-336), nto leyo ebonisa ukuba izibulali-zinambuzane ezifundwayo zibeka umngcipheko omkhulu kwiintlobo ezahlukeneyo ze-amphibian. Xa kujongwa ukuba i-P. gracilis ifuna malunga neentsuku ezingama-30 ukugqiba i-metamorphosis56, kunokugqitywa kwelokuba amazinga afundwayo e-cypermethrin anokuba negalelo ekunciphiseni inani labantu ngokuthintela abantu abanentsholongwane ukuba bangene kwinqanaba lokukhula okanye lokuzala besebancinci.
Kuvavanyo lomngcipheko olubaliweyo lwe-micronuclei kunye nezinye iingxaki zenyukliya ze-erythrocyte, amaxabiso e-CHQ aqala kwi-14.92 ukuya kwi-97.00, nto leyo ebonisa ukuba i-cypermethrin yayinomngcipheko we-genotoxic kwi-P. gracilis nakwindawo yayo yendalo yokuhlala. Xa kujongwa ukufa, uxinaniso oluphezulu lwee-xenobiotic compounds ezinyamezelekayo kwi-P. gracilis yayiyi-4.24 μg L−1. Nangona kunjalo, uxinaniso oluphantsi njenge-1 μg/L lukwabonise iziphumo ze-genotoxic. Le nyaniso inokukhokelela ekwandeni kwenani lezidalwa ezingaqhelekanga57 kwaye ichaphazele uphuhliso kunye nokuzala kweentlobo kwiindawo zazo zokuhlala, nto leyo ekhokelela ekwehleni kwabemi be-amphibian.
Iifomyula zentengiso ze-cypermethrin yesibulali-zinambuzane zibonise ubuthi obuphezulu obubukhali nobungapheliyo kwi-P. gracilis. Amanani aphezulu okufa abonwe, mhlawumbi ngenxa yeziphumo ezinobuthi, njengoko kungqinwa bubukho be-micronuclei kunye ne-erythrocyte nuclei ezingaqhelekanga, ngakumbi ii-nuclei ezirhabaxa, ii-nuclei ezixineneyo, kunye nee-vesicular nuclei. Ukongeza, iintlobo ezifundwayo zibonise umngcipheko okhulayo wokusingqongileyo, zombini ezirhabaxa nezingapheliyo. Olu lwazi, ludibene nezifundo zangaphambili zeqela lethu lophando, lubonise ukuba neefomyula zentengiso ezahlukeneyo ze-cypermethrin zisabangela ukwehla kwemisebenzi ye-acetylcholinesterase (AChE) kunye ne-butyrylcholinesterase (BChE) kunye noxinzelelo lwe-oxidative58, kwaye kwaphumela kutshintsho kumsebenzi wokubhukuda kunye nokukhubazeka komlomo59 kwi-P. gracilis, okubonisa ukuba iifomyula zentengiso ze-cypermethrin zinobuthi obuphezulu obubulalayo nobungaphantsi kobu luhlobo. UHartmann et al. I-60 ifumanise ukuba iifomyula zorhwebo ze-cypermethrin zezona zinobungozi kakhulu kwi-P. gracilis kunye nolunye uhlobo lohlobo olufanayo (i-P. cuvieri) xa kuthelekiswa nezinye izibulali-zinambuzane ezilithoba. Oku kubonisa ukuba amazinga avunyiweyo ngokusemthethweni e-cypermethrin okukhusela okusingqongileyo anokubangela ukufa okuphezulu kunye nokuncipha kwabemi ixesha elide.
Kufuneka uphando olongezelelekileyo ukuze kuvavanywe ubuthi besibulali-zinambuzane kwizilwanyana eziphila emanzini, njengoko ubuninzi obufumaneka kwindawo engqongileyo bunokubangela ukufa okuphezulu kwaye bube yingozi kwi-P. gracilis. Kufuneka kukhuthazwe uphando ngeentlobo zezilwanyana eziphila emanzini, njengoko idatha ngezi zinto ziphilayo inqabile, ingakumbi kwiintlobo zaseBrazil.
Uvavanyo lwetyhefu olungapheliyo lwathatha iiyure ezili-168 (iintsuku ezi-7) phantsi kweemeko ezingashukumiyo kwaye ubuninzi obungaphantsi kobu bubu: 1, 3, 6 kunye ne-20 μg ai L−1. Kuzo zombini iimvavanyo, ii-tadpoles ezili-10 kwiqela ngalinye lonyango zavavanywa ngeekopi ezintandathu, ukuze kubekho ii-tadpoles ezingama-60 ngoxinzelelo ngalunye. Okwangoku, unyango lwamanzi kuphela lwalusebenza njengolawulo olubi. Ukuseta ngakunye kovavanyo kwakuquka isitya seglasi esingenazintsholongwane esinomthamo we-500 ml kunye noxinano lwe-tadpole e-1 kwi-50 ml yesisombululo. Iflaski yayigqunywe ngefilimu ye-polyethylene ukuthintela ukufuma kwaye yayihlala ivuthelwa umoya.
Amanzi ahlalutywe ngokweekhemikhali ukuze kufunyanwe ubuninzi bezinambuzane ezibulala izinambuzane kwiiyure eziyi-0, 96, kunye ne-168. Ngokutsho kukaSabin et al. 68 kunye noMartins et al. 69, uhlalutyo lwenziwe kwiLebhu yoHlalutyo lweZibulali (i-LARP) yeFederal University yaseSanta Maria kusetyenziswa i-gas chromatography edityaniswe ne-triple quadrupole mass spectrometry (i-Varian model 1200, ePalo Alto, eCalifornia, e-USA). Ukuqinisekiswa kobungakanani bezinambuzane ezibulala izinambuzane emanzini kuboniswa njengezinto ezongezelelweyo (Itheyibhile SM1).
Kwi-micronucleus test (MNT) kunye ne-red cell nuclear abnormality test (RNA), kwahlalutywa ii-tadpoles ezili-15 kwiqela ngalinye lonyango. Ii-tadpoles zafakwa i-anesthetised nge-5% ye-lidocaine (50 mg g-170) kwaye iisampulu zegazi zaqokelelwa ngokubhoboza intliziyo kusetyenziswa iisirinji ezilahlwayo ze-heparinized. Ii-blood smears zalungiswa kwii-microscope slides ezicocekileyo, zomiswa emoyeni, zalungiswa nge-100% methanol (4 °C) imizuzu emi-2, zaza zafakwa i-10% yesisombululo seGiemsa imizuzu eli-15 ebumnyameni. Ekupheleni kwenkqubo, ii-slides zahlanjwa ngamanzi acocekileyo ukususa amabala agqithisileyo zaza zomiswa kubushushu begumbi.
Ubuncinane ii-RBC ezili-1000 ezivela kwi-tadpole nganye zihlalutywe kusetyenziswa i-microscope eyi-100× ene-71 objective ukufumanisa ubukho be-MN kunye ne-ENA. Ii-RBC ezingama-75,796 ezivela kwi-tadpoles zivavanyiwe kujongwa ubuninzi be-cypermethrin kunye nolawulo. Ubuthi be-genotoxicity buhlalutywe ngokwendlela kaCarrasco et al. kunye noFenech et al.38,72 ngokufumanisa ubuninzi bezilonda zenyukliya ezilandelayo: (1) ii-anucleate cells: iiseli ezingenazo ii-nuclei; (2) ii-apoptotic cells: ukuqhekeka kwenyukliya, ukufa kweeseli okucwangcisiweyo; (3) ii-binucleate cells: iiseli ezinee-nuclei ezimbini; (4) ii-nuclei buds okanye ii-bleb cells: iiseli ezinee-nuclei ezinee-protrusions ezincinci ze-nuclei membrane, ii-blebs ezifanayo ngobukhulu be-micronuclei; (5) ii-karyolyzed cells: iiseli ezine-outline ye-nucleus kuphela ngaphandle kwezinto zangaphakathi; (6) ii-notched cells: iiseli ezinee-nuclei ezinee-cracks ezicacileyo okanye ii-notches kwimo yazo, ezikwabizwa ngokuba yi-kidney-shaped nuclei; (7) iiseli ezibunjiweyo: iiseli ezinee-nuclear protrusions ezinkulu kunee-vesicles ezikhankanyiweyo apha ngasentla; kunye (8) ii-microcells: iiseli ezine-nuclei ezixineneyo kunye ne-cytoplasm enciphileyo. Utshintsho luthelekiswe neziphumo zolawulo olubi.
Iziphumo zovavanyo lwetyhefu olukhawulezileyo (LC50) zihlalutywe kusetyenziswa isoftware ye-GBasic kunye nendlela ye-TSK-Trimmed Spearman-Karber74. Idatha yovavanyo olungapheliyo ivavanywe kwangaphambili ukuze ifumane ulungelelwaniso lwempazamo (Shapiro-Wilks) kunye nokuhambelana kokwahluka (Bartlett). Iziphumo zihlalutywe kusetyenziswa uhlalutyo lwe-one-way of variance (ANOVA). Uvavanyo lukaTukey lusetyenziselwe ukuthelekisa idatha phakathi kwabo, kwaye uvavanyo lukaDunnett lusetyenziselwe ukuthelekisa idatha phakathi kweqela lonyango kunye neqela lolawulo olungalunganga.
Idatha ye-LOEC kunye ne-NOEC ihlalutywe kusetyenziswa uvavanyo lukaDunnett. Uvavanyo lwezibalo lwenziwe kusetyenziswa isoftware yeStatistica 8.0 (StatSoft) enenqanaba lokubaluleka eliyi-95% (p < 0.05).
Ixesha leposi: Matshi-13-2025