Ngo-Agasti, osokhemisi bamemezela ukuthi bangenza lokho osekunesikhathi eside kubonakala kungenakwenzeka: ukudiliza ezinye zezinto ezihlala isikhathi eside ezingcolisa imvelo ngaphansi kwezimo ezithambile.Izinto ze-Per- kanye ne-polyfluoroalkyl (PFAS), ezivame ukubizwa ngokuthi amakhemikhali angunaphakade, zinqwabelana emvelweni nasemizimbeni yethu ngesivinini esishaqisayo.Ukuqina kwazo, okugxilwe kusibopho se-carbon-fluorine esinzima ukunqamula, kwenza i-PFAS isebenziseke ikakhulukazi njengezingubo ezingangeni manzi nezingamanti namagwebu acisha umlilo, kodwa kusho ukuthi amakhemikhali aphikelela amakhulu eminyaka.Amanye amalungu alesi sigaba esikhulu sezinhlanganisela aziwa ukuthi anobuthi.
Ithimba, eliholwa ngusokhemisi weNyuvesi yaseNorthwestern uWilliam Dichtel kanye nomfundi owabe esethweswa iziqu uBrittany Trang, bathola ubuthakathaka ku-perfluoroalkyl carboxylic acid kanye namakhemikhali iGenX, okuyingxenye yelinye ikilasi le-PFAS.Ukushisisa izinhlanganisela kukliphu ezincibilikayo eqenjini le-carboxylic acid yamakhemikhali;ukungezwa kwe-sodium hydroxide kwenza wonke umsebenzi, kushiye ama-ion e-fluoride nama-molecule e-organic engalungile.Lokhu kwephulwa kwebhondi ye-C–F eqine ngokwedlulele kungafezwa ngo-120 °C nje (Isayensi 2022, DOI: 10.1126/science.abm8868).Ososayensi banethemba lokuhlola indlela ngokumelene nezinye izinhlobo ze-PFAS.
Ngaphambi kwalo msebenzi, amasu angcono kakhulu okulungisa i-PFAS bekuwukuhlanganisa amakhompiyutha noma ukuwaphule emazingeni okushisa aphakeme kakhulu kusetshenziswa amandla amakhulu — okungenzeka angasebenzi nhlobo, kusho uJennifer Faust, usokhemisi eKolishi laseWooster.“Yingakho le nqubo yezinga lokushisa eliphansi ithembisa ngempela,” usho kanje.
Le ndlela entsha yokuhlukanisa yamukelekile ikakhulukazi kumongo wezinye izinto ezitholwe ngo-2022 mayelana ne-PFAS.Ngo-Agasti, abacwaningi baseNyuvesi yaseStockholm abaholwa ngu-Ian Cousins babika ukuthi amanzi emvula emhlabeni jikelele aqukethe amazinga e-perfluorooctanoic acid (PFOA) adlula izinga lokweluleka le-US Environmental Protection Agency kulelo khemikhali emanzini okuphuza (Environ. Sci. Technol. 2022, DOI: 10.1021 /acs.est.2c02765).Ucwaningo luthole amazinga aphezulu amanye ama-PFAS emanzini emvula nawo.
"I-PFOA ne-PFOS [i-perfluorooctanesulfonic acid] sekungamashumi eminyaka ingasebenzi, ngakho-ke ikhombisa ukuthi iphikelela kangakanani," kusho uFaust.“Bengingacabangi ukuthi kuzoba okungaka.”Uthi umsebenzi wabazala, “uyingqopha-mlando ngempela.”U-Faust uthole izinhlobo ezintsha ze-PFAS—lezo ezingaqashwa njalo yi-EPA—emanzini emvula ase-US ezindaweni eziphakeme kakhulu kunalezi zinhlanganisela zefa (I-Environ. Sci.: Izinqubo Zemithelela 2022, DOI: 10.1039/d2em00349j).
Isikhathi sokuthumela: Dec-19-2022