PHOTOPROTECTION (NUMITKI SAKTI-ENERGY DAGI NGAKTHOKPA)

Numit ashi prithibi da jiba panba singgi damakta yamma maru oi. Numittagi thadorakliba sakti (energy) sing ashi leiramdarbadi prithibida jiba sing leiramloi. Prithibida houriba mana masing, upal wapal, pumba numit ki mangal, carbon amadi eshing na oithokhanbani. Fossil records gi matung ina ihan hanbada prithibi gi kuyomda ozone leiramde amadi oxygen gi chang yamna pikna leirami. Maram ashina tamthiraba numitki sakti (energy) yamna kanba Ultraviolet radiation na maram oiraga prithibigi leimaida jiba leiba ngamlamde. Maram ashina meihourolgi matamda jiba panba sing ashi ishing gi manung tada leiba ngamlami. Mashimak ishing na piba photoprotection makhal amani. Ashumna chatharakpana, pambi singna hounanabagi damak photosynthesis ki mathou tai amadi masigidamak visible light darker oi. Visible light na eshing phaona changkhiduna, tapna tapna eshing manungda pambi sing hourktuna, photosynthesis gi process thuna sandorakhi. Loinana, pambi singna oxygen thadoraktuna prithibi gi leimaida oxygen marang kaina phanglakhi. Numitki radiation gi matengna oxygen dagi ozone layer semlakhi amasung atmosphare gi mathak thangba sarukta ozone gi kuyom ama semlakhi. Asumna mahousagi yamna taseng taseng ba photo protection (prevention of damages of solar radiation) makal ani na prithibi gi kuyom kupshinlakhi. Mapal thangba ‘Ionosphere’ na X-ray gi radiation sundrangda (space) da thakthokhi aduga ozone gi layer na UVC chupsankhi. Masiga iroinana, nugshita yaoriba ishing gi manilna Infra red radiation gi saruk kaya amasu chupsanli. Mathakta pankhriba sing asi nature na eikhoi da pibiramba , yamna mayek sengna, prithibi da jiba panba lingba/hingba ngamnanaba photoprotection gi chaoraba khudol ni. Laibak thibana chaokhatlakpaga (industrialisation) iroinana, eikoina sijanariba pambei kayadagi thadorakpa chemical singna, nungshit ki kuyomda yaoriba ozone ashi yamna manghanli (destruction). Khawaida gi maru oina refrigerants amasung propellants spray sing da sijanariba CFL (chloroflurocarbons) na athoibani. Scientist sing na asumna pai, madudi ozone gi layer dagi 1.0% hanthaba matamda, numitki mangaldagi UVB prithibi gi laimaida hena youhanbana maram oiraga, unsagi cancer sing, Squamous cell carcinoma da 2.5% amasung Basal cell carcinoma da 1.5% mahusadagi hena oihanba yai.

Mioibana hingnabagi lambida nungshada khramakhei phouba/yaiba (exposure) tangai phade adumakpu hena phoumalabadi akaiba kaya lei. Eikhoi mioibagi damakta di, mahousagi (nature) photo protection gi khudol ashi makna numitki radiation dagi mapung phana ngakthokpa ngamde. Maram ashina meihourol da gi houna mioibana, phirol, tupi, kokset, satilna chingba kaya ama nungshadagi ngakthoknaba gi damak sijanadu na lakli. Loinana eikhoina urum warumgi upai kaya sijinei. Masimak miobana primitive oiringeigi matamdagi houna, crude (achamba) oiba maong da adum sijinarakhi. Masida natana mioibana chaokhataringei gi matamda, masada, leikhom, mineral crusts(dhatugi magul chenba leibak), mana masinggi mahi, thaona ching ba unsada teisinduna photoprotection tourami.

Egyptian, Romans, Greek amadi nongpoklomgi leibaksingda mamag ngeida gi houna nupisg na maida, unsada, lead paints, arsenic salts , chalks, olive oil na chingba kaya sijinarami. 1920 gi matung tarakpa aduwaidagi di ‘sun tanning’ gi fashion, haibadi nungsa da atamnana yaiduna amadi outdoor gi activities kaya ama touduna unsa musalhanbagi chatnabi hourakhi. Masigi khudong chadaba oina ‘Sun burn’ toubagi chang su yamna hengatlakhi. 1922 da ‘Hansser amasung Vahle’ na unsagi ‘sun burn’ touriba ashi akhanaba nungsagi radiation gi range kharana (280-315 nm) nani haiba khanglaki amadi report toukhi. Mashigi matung tarakpa dagi di ‘photo protection amasung sunscreen’ gi anouba yaol ama hourakhi. Second world war gi matam da US lanmising na ashaba/nugsa saba maphamsingda lal chatpada ‘Red petrolatum’ maida teiduna sun burn dagi ngakthoknaba marang kaina sijanakhi. 1943 da ahanba oina PABA(para amino benzoic acid), chemical sunscreen oina patented toukhi.

SUNSCREENS:

Sunscreens sing ashi unsada (maru oina nungsana phugadaba mapham singda) teiduna nungsagi radiation singdagi ngakthoknaba (UVB amasung UVA) chemicals singni. Ahanbada eikhoina khangadabadi, sunscreen ashi nungsada hena kuina leinanaba gi damak (leiba ngamnanaba) sijanagadaba nate. Tangaiphadana eikhoigi day to day life ki outdoor activities da nungsagi radiation dagi ngakthoknaba pambei oina sijanagadabani.

Sunscreen na nungsagi radiation da yaoriba UVB, UVA amasung visible light pu, thaktokhankhiba, chaithokhankhiba amasung chupsanduna nungsagi radiation gi energy mayeng tahanli amadi manghankhi. Makhoi ashi creams, lotions, gels natraga sprays oina sai. Suncreen ashi unsa sokhandaba (allergic reaction touhandaba) amadi chupsankharaba matungda nung gi oiba (systemic reactions) amata thokhandaba tangaiphade. Mashi ga loinana, unshada teiraba matungda kuina chemically stable (magul mangdana) leiba ngamba tai. Sunscreen sijana ba hourakpagi matamda, atamnana sunburn thokhanliba UVB radiation dagi ngathoknaba gi damak design/formulation da mityeng thamkhi. Matung tarakpada UVA na unsada thokhanba (maru oina, pigmentations, photo aging) amangba singsu khanglakpadagi, puna UVB amasung UVA ngathokpa ngamba formulation kaya design toure. Masidagi hendokna, visible light ki saruk kharasu ngathokpa ngamba, water resistant (humang amasung eshing) singsu marketing toure.

Sunscreen ashi makhagi ashigumna neina ba yai:

• Physical sunscreen: Makhoi ashi di inorganic particles na sembani. Masina maru oina numitki radiation ashi thaktokhanli amasung chaithokkhiba (scattered) ga loinana energy adu khara makheisu chupsanli (absorbed). Masida sijanariba chemicals singdi, zinc oxide, titanium dioxide na ayambani. Ahanbada inorganic particles singsi makup poubana maram oiraga sijanabada cosmetically yengba nungaihande. Houjikti ultra micronized particles gi formulation leire amadi cosmetically phjana chatnaba yaba maong da sijinaba yare. Physical sunscreen di unsada reactions (allergic) thokande amasung sijanabada meisa sagatpa phoude, ing ing laoba sensation phange.
• Chemical sunscreen: Makhal ashigi sunscreen singdi organic compounds singna sembani. Masina nungsagi radiation bu chupsanduna heat energy oina onthktuna nungsagi radiation effect manghanli, maram ashina sijinaraba matungda, nungsana yeibada unsada meisa sagatpa (warmness) phaoe.
  Houjikti physical amadi chemical punsanlaga semba hena effective oiba, sijinabada nungaiba sunscreen kayasu marketing toure.
• UV (ultra violet ray) filters: FDA(US) gi monograph gi matung ina- (i) UVA filters, (ii) UVB filters amasung, (iii) Inorganic filters haina khaidoki.
  • UVA filters da sijanariba maru oiba machal singdi : Oxybenzone, Sulisobenzone, Dioxybenzone, Avobenzone, Meradimate, Ecamsule na chingbani.
  • UVB filters da sijinariba maru oiba machal singdi: PABA, Padimate-o, Cinnamates, Salicylates. Octocrylele, Ensulizole na chingbani.
  • INORGANIC filters gi maru oiba potsaksingdi: Titanium di oxide amasung Zinc oxide ni.
• WATER RESISTANT sunscreen: FDA gi matung ina sunscreen amana unsada teiraba matungda, unsadu ishing da minute 20 tingbada, sunscreen gi magul hanthadana leiba ngamba sunscree dubu “water reistant sunscreen” haina khangnei.

Sun Protection Factor (SPF): Sunscreen amagi magul kanba natraga sonba (effectiveness) ashi SPF gi pathap (pambeina) phongdoke. Franz Greiter(Austrian) na 1962 da ahanba oina design toukhi amadi matung tarakpada 1978 da FDA na ayaba pikhi.

Pathap ashi khangnabagi damak MED (Minimal erythema dose) hana khangba darker oi. UVB na protect toudaba (natural oiba unsha) unsada yeiba matamda, khwaida gi hanthba (minimum) changda thokhanba erythema (angangba reaction) ngamba enery gi dose adubu MED koui.

SPF haiba taragadi: Protected (sunscreen niyom chumna teiraba) unsada UVB na khawaidagi hanthana erythema thokhanba ngamba energy dose da – Unprotected unsada UVB na khawaidagi hanthana erythema thokhanba ngamba energy dose na yennaraga phangba pholbu (divided result) SPF haina khangnei. SPF puthoknaba gi damak khusemgi oiba ‘solar stimulator with emission spectrum: 290-400 nm gi pangal liba energy source, amasung sunscreen adu 2mg/sq.cm gi changda teigadabani.

SPF = MED PROTECTED SKIN/MED UNPROTECTED SKIN
SPF 10 leiba (laborator) sunscreen amana niyom chuma unsada teiba tarabadi, teidaba unsadadi saruk tara erythema thokhandaba ngmgani. Adumakpu masidagi SPF ashi wangkhatlak kharabadi, mathakta pankhriba laboratory amasung natural nungsagi pathap asi chumlkte. Sunscreen ashi practical oina sijanabadadi magul asi mak phangba ngamde, maramdi, eikhoina sunscreen sijinabada laboratory gi dose (chang) du youna keidounung da teide. Aduna chaorakna SPF 15 na 93% aduga SPF 34 na 97% gumba erythema dagi ngakthokpa ngami.

KAYAM TOINA (FREQUENCY), AMADI SPF KARAMBA SUNSCREEN SIJANAGANI
Masi makti mi mi dugi physical (outdoor) activities, profession, masagi kuchu gi phibham amadi masagi oina nungsada sensitive oiganba natraga oigandaba gi makha pongani. Changchata ayuk nungsa haigatlakpa gi matamda ahanba dose teigani amasung matung tarakpada, matikchaba sunscreen effect phangnanaba pung ahum khudingi hana hana, numitna haitharaktri phaoba teigani. Eikhoi gi lamdam sigi oina amadi eikhoigi changchatki kutchu gi phibham, samajgi chatnabi (lifestyle), mayam ashi yengluraga, changchata anirak natraga ahumlak sunscreen teibana kanaba phangani. Khangjanba da kanaba amana nongmagi ahanba sunscreen dose dagi anisuba- amasung ahumsuba dose na ahanba dose dagi, chaorakna saruk ahumgumba nungsadagi ngathokpagi (erythema) pangal heli.Loinana kutchu ngouba singna SPF yamba amadi kutchu leisinba singna SPF hanthaba sunscree sijanagani.

Dr. Karam Lokendro, MD