I-Dioxane？ Kumane kuyindaba yobandlululo

Iyini i-dioxane? Ivelaphi?

I-Dioxane, indlela efanele yokuyibhala yi-dioxane. Ngenxa yokuthi ububi kunzima kakhulu ukuthayipha, kulesi sihloko sizosebenzisa amagama amabi avamile esikhundleni salokho. Kuyinhlanganisela yezinto eziphilayo, eyaziwa nangokuthi i-dioxane, i-1, i-4-dioxane, uketshezi olungenambala. Ubuthi obukhulu be-Dioxane bunobuthi obuphansi, bunemiphumela yokubulala izinzwa kanye nokuvuselela. Ngokusho kweKhodi Yobuchwepheshe Bokuphepha Yamanje Yezimonyo eShayina, i-dioxane iyisakhi esivinjelwe sezimonyo. Njengoba kuvinjelwe ukwengeza, kungani izimonyo zisatholakala nge-dioxane? Ngezizathu ezingenakugwenywa ngokobuchwepheshe, kungenzeka ukuthi i-dioxane ifakwe ezimonyweni njengokungcola. Ngakho-ke yiziphi izinto ezingcolile ezitholakala ezintweni zokusetshenziswa?

Esinye sezithako zokuhlanza ezisetshenziswa kakhulu kuma-shampoo kanye nokuwasha umzimba yi-sodium fatty alcohol ether sulfate, eyaziwa nangokuthi i-sodium AES noma i-SLES. Lesi sakhi singenziwa ngamafutha esundu emvelo noma i-petroleum njengezinto zokusetshenziswa zibe ama-fatty alcohols, kodwa sakhiwa ngochungechunge lwezinyathelo ezifana ne-ethoxylation, i-sulfonation, kanye ne-neutralization. Isinyathelo esibalulekile yi-ethoxylation, kulesi sinyathelo senqubo yokusabela, udinga ukusebenzisa izinto zokusetshenziswa ze-ethylene oxide, okuyi-monomer yezinto zokusetshenziswa ezisetshenziswa kakhulu embonini yokwenziwa kwamakhemikhali, enkambisweni yokusabela kwe-ethoxylation, ngaphezu kokwengezwa kwe-ethylene oxide ku-fatty alcohol ukukhiqiza i-ethoxylated fatty alcohol. Kukhona nengxenye encane ye-ethylene oxide (EO) ama-molecule amabili amabili ukujiya ukukhiqiza umkhiqizo olandelanayo, okungukuthi, isitha se-dioxane, ukusabela okuthile kungaboniswa esithombeni esilandelayo:

Ngokuvamile, abakhiqizi bezinto zokusetshenziswa bazoba nezinyathelo zakamuva zokuhlukanisa nokuhlanza i-dioxane, abakhiqizi bezinto zokusetshenziswa ezahlukene bazoba nezindinganiso ezahlukene, abakhiqizi bezimonyo bamazwe ngamazwe bazolawula lesi sibonakaliso, ngokuvamile cishe ngo-20 kuya ku-40ppm. Ngokuphathelene nezindinganiso zokuqukethwe kumkhiqizo oqediwe (njenge-shampoo, ukugeza umzimba), azikho izinkomba ezithile zomhlaba wonke. Ngemva kwesigameko se-shampoo saseBawang ngo-2011, iShayina yabeka indinganiso yemikhiqizo eqediwe ngaphansi kuka-30ppm.

I-Dioxane ibangela umdlavuza, ingabe ibangela ukukhathazeka ngokuphepha?

Njengezinto zokusetshenziswa ezisetshenziswa kusukela eMpini Yezwe II, i-sodium sulfate (SLES) kanye ne-dioxane yayo ephuma eceleni kuye kwafundwa kabanzi. I-United States Food and Drug Administration (FDA) ibilokhu ifunda i-dioxane emikhiqizweni yabathengi iminyaka engama-30, kanti i-Health Canada iphethe ngokuthi ukuba khona kwamanani amancane e-dioxane emikhiqizweni yezimonyo akubangeli ingozi empilweni yabathengi, ngisho nezingane (eCanada). Ngokusho kwe-Australian National Occupational Health and Safety Commission, umkhawulo ofanele we-dioxane ezimpahleni zabathengi ngu-30ppm, kanti umkhawulo ophezulu wokwamukeleka kobuthi ngu-100ppm. E-China, ngemuva kuka-2012, izinga elilinganiselwe lika-30ppm lokuqukethwe kwe-dioxane ezimonyweni liphansi kakhulu kunomkhawulo ophezulu owamukelekayo ngokobuthi ongu-100ppm ngaphansi kwezimo ezijwayelekile zokusetshenziswa.

Ngakolunye uhlangothi, kufanele kugcizelelwe ukuthi umkhawulo we-dioxane eShayina ezindinganisweni zezimonyo ungaphansi kwama-30ppm, okuyindinganiso ephezulu emhlabeni. Ngoba empeleni, amazwe amaningi nezifunda zinemikhawulo ephezulu kokuqukethwe kwe-dioxane kunezindinganiso zethu ezijwayelekile noma azikho nhlobo izindinganiso ezicacile:

Eqinisweni, amanani amancane e-dioxane nawo avamile ngokwemvelo. I-US Toxic Substances and Disease Registry ibala i-dioxane njengetholakala enkukhu, utamatisi, i-shrimp ngisho nasemanzini ethu okuphuza. Iziqondiso ze-World Health Organization zekhwalithi yamanzi okuphuza (uhlelo lwesithathu) zithi umkhawulo we-dioxane emanzini ngu-50 μg/L.

Ngakho-ke ukufingqa inkinga ebangela umdlavuza ye-dioxane ngomusho owodwa, okungukuthi: kungakhathaliseki ukuthi umthamo ungakanani ukukhuluma ngomonakalo kuyinkohliso.

Uma okuqukethwe kwe-dioxane kuphansi, kulapho ikhwalithi iba ngcono khona, akunjalo?

I-Dioxane akuyona yodwa inkomba yekhwalithi ye-SLES. Ezinye izinkomba ezifana nenani lamakhemikhali angenasulfona kanye nenani lezinto ezicasulayo emkhiqizweni nazo zibalulekile ukuzicabangela.

Ngaphezu kwalokho, kubalulekile ukuqaphela ukuthi ama-SLES nawo eza ngobukhulu obuhlukene, umehluko omkhulu yizinga le-ethoxylation, amanye ane-1 EO, amanye ane-2, 3 noma ngisho ne-4 EO (vele, imikhiqizo enezindawo zamadesimali ezifana no-1.3 no-2.6 nayo ingakhiqizwa). Uma izinga le-ethoxidation ekhuphukile liphezulu, okungukuthi, inani le-EO liphakeme, kulapho okuqukethwe kwe-dioxane okukhiqizwa ngaphansi kwenqubo efanayo kanye nezimo zokuhlanzwa kuphakeme.

Nokho, ngokuthakazelisayo, isizathu sokwandisa i-EO ukunciphisa ukucasuka kwe-surfactant SLES, futhi uma inani le-EO SLES likhuphuka, kulapho isikhumba singacasuki khona, okungukuthi, sithambile, futhi okuphambene nalokho. Ngaphandle kwe-EO, yi-SLS, engathandwa yizakhi zayo, okuyisithako esikhuthazayo kakhulu.

Ngakho-ke, okuqukethwe okuphansi kwe-dioxane akusho ukuthi empeleni kuyinto eluhlaza enhle. Ngoba uma inani le-EO lincane, ukucasuka kwezinto zokusetshenziswa kuzoba kukhulu.

Ngokufigqiwe:

I-Dioxane ayisona isithako esengezwe amabhizinisi, kodwa iyinto eluhlaza okumele ihlale ezintweni zokusetshenziswa ezifana ne-SLES, okunzima ukuyigwema. Hhayi ku-SLES kuphela, empeleni, uma nje kwenziwa i-ethoxylation, kuzoba khona inani elincane le-dioxane, futhi ezinye izinto zokusetshenziswa zokunakekelwa kwesikhumba nazo ziqukethe i-dioxane. Ngokombono wokuhlolwa kwengozi, njengento esele, asikho isidingo sokuphishekela okuqukethwe okungu-0 okuphelele, uma kuthathwa ubuchwepheshe bokuthola bamanje, "okungatholakali" akusho ukuthi okuqukethwe kungu-0.

Ngakho-ke, ukukhuluma ngomonakalo ongaphezu komthamo kuwukuba yi-gangster. Ukuphepha kwe-dioxane sekufundwe iminyaka eminingi, futhi ukuphepha okufanele kanye nezindinganiso ezinconyiwe sekumisiwe, kanti izinsalela ezingaphansi kwe-100ppm zibhekwa njengeziphephile. Kodwa amazwe afana ne-European Union awazange akwenze kube yindinganiso ephoqelekile. Izidingo zasekhaya zokuqukethwe kwe-dioxane emikhiqizweni zingaphansi kwe-30ppm.

Ngakho-ke, i-dioxane ekwi-shampoo akudingeki ikhathazeke ngomdlavuza. Ngokuphathelene nokwaziswa okungaqondile kwabezindaba, manje usuyaqonda ukuthi kumane nje kudonsela ukunaka.