Ngo-2019, i-US FDA yamemezela isiphakamiso esisha esithi phakathi kwezithako ezisebenzayo ezingu-16 ze-sunscreen ezikhona emakethe yase-US, i-zinc oxide kanye ne-titanium dioxide zengezwa emikhiqizweni ye-sunscreen njenge-“GRASE” (Ngokuvamile yaziwa njengephephile futhi isebenza kahle). I-PABA kanye ne-Trolamine Salicylate akuzona “i-GRASE” ezisetshenziswa kuma-sunscreen ngenxa yezinkinga zokuphepha. Kodwa-ke, lokhu okuqukethwe kukhishwe emongweni, futhi kuyaqondakala ukuthi ama-sunscreen agents kuphela angokoqobo - i-nano zinc oxide kanye ne-titanium dioxide - aphephile futhi asebenza kahle ezithakweni ezisebenzayo zama-sunscreen, amanye ama-sunscreen agents amakhemikhali awaphephile futhi ayasebenza. Eqinisweni, ukuqonda okulungile ukuthi yize i-US FDA ibheka i-nano-zinc oxide kanye ne-titanium dioxide njenge-“GRASE”, akusho ukuthi amanye ama-sunscreen agents amakhemikhali angu-12 awawona ama-GRASE, kodwa asantula idatha eyanele yokuphepha yokubonisa. Ngesikhathi esifanayo, i-FDA icela nezinkampani ezifanele ukuthi zinikeze idatha eyengeziwe yokusekela ukuphepha.
Ngaphezu kwalokho, i-FDA iphinde yenza isivivinyo somtholampilo "sokumuncwa kwe-sunscreen ngesikhumba iye egazini" futhi yathola ukuthi ezinye izithako ezisebenzayo ze-sunscreen ezikwi-sunscreen, uma zimuncwa umzimba ezingeni eliphezulu, zingadala izinkinga zempilo. Lapho nje imiphumela yokuhlolwa ishicilelwe, yavusa ingxoxo ebanzi emhlabeni wonke, futhi kancane kancane yabangela ukungaqondani ngabathengi abavamile ababengalazi iqiniso. Babekholelwa ngqo ukuthi i-sunscreen ingangena egazini futhi ayiphephile emzimbeni womuntu, futhi ngisho nohlangothi olulodwa babekholelwa ukuthi i-sunscreen iyingozi empilweni futhi ayinakusetshenziswa.
Kubikwa ukuthi i-FDA iqashe abantu abavolontiya abangu-24, bahlukaniswa ngamaqembu angu-4, futhi bahlola ama-sunscreen aqukethe ama-sunscreen angu-4 ahlukene kule fomula. Okokuqala, abantu abavolontiya banikele ngo-75% wesikhumba sonke somzimba, ngokwesilinganiso esijwayelekile esingu-2mg/cm2, izikhathi ezingu-4 ngosuku izinsuku ezingu-4 zilandelana ukuze basebenzise i-sunscreen. Ngemuva kwalokho, amasampula egazi abantu abavolontiya aqoqwa izinsuku ezingu-7 zilandelana futhi okuqukethwe yi-sunscreen egazini kwahlolwa. Izifundo zibonise ukuthi indawo yesikhumba somuntu omdala cishe ingu-1.5-2 ㎡. Uma sibheka inani elimaphakathi elingu-1.8 ㎡, uma libalwa ngokwenani elijwayelekile, ukusetshenziswa kwe-sunscreen yilabo abavolontiya cishe kungu-2 × 1.8 × 10000/1000 = 36g ekuhlolweni, kanti inani lezikhathi ezingu-4 ngosuku lingu-36 × 4 = 144g. Ngokuvamile, indawo yesikhumba sobuso cishe ingu-300-350cm², ukusetshenziswa okukodwa kwe-sunscreen kwanele ukuvikela usuku lonke. Ngale ndlela, inani lokusetshenziswa elibaliwe lingu-2×350/1000=0.7g, noma ngabe upende kabusha ufakiwe, cishe u-1 .0 ~1.5g. Uma uthatha inani eliphakeme kakhulu lamagremu angu-1.5, ukubalwa kungu-144/1.5=izikhathi ezingu-96. Futhi inani le-sunscreen elisetshenziswa yizisebenzi zokuzithandela izinsuku ezine zilandelana lingu-144×4=576g, kanti inani le-sunscreen elisetshenziswa nsuku zonke ngabantu abavamile izinsuku ezine lingu-1.5×4=6g. Ngakho-ke, umehluko phakathi komthamo wamagremu angu-576 namagremu angu-6 e-sunscreen mkhulu kakhulu futhi umthelela usobala.
Ama-sunscreen ahlolwe yi-FDA kulolu vivinyo kwakuyi-benzophenone-3, i-octoclilin, i-avobenzone, kanye ne-TDSA. Phakathi kwazo, idatha yokuthola i-benzophenone-3 kuphela edlula kakhulu lokho okubizwa ngokuthi “inani lokuphepha”, cishe izikhathi ezingu-400 idlula izinga elijwayelekile, i-octocrylene kanye ne-avobenzone zombili zingaphakathi kwezikhathi eziyi-10, kanti i-p-xylylenedicamphorsulfonic acid ayitholakali.
Ngokwenkolelo-mbono, ukusetshenziswa okuqhubekayo kwe-sunscreen ngamandla amakhulu kuzobangela umphumela oqongelelekayo. Akumangazi ukuthi ngisho ne-sunscreen itholakala egazini ngaphansi kwezimo ezinzima kangaka zokuhlolwa. I-sunscreens iye yavunyelwa futhi yasetshenziswa iminyaka engaphezu kwamashumi eminyaka, amazwe amaningi alawule i-sunscreens njengemithi, futhi kuze kube manje akukho idatha yocwaningo eyanele yokufakazela ukuthi inemiphumela emibi emzimbeni womuntu.
Isikhathi sokuthunyelwe: Septhemba-09-2022
