SUNSCREENS

burns moderately, tans gradually

20

always burns easily, tans minimally

20 to 30

what range do UVB filters absorb in?

290-320 nm

always burns easily, rarely tans

30+ spf

what range do UVA organic sunscreen filters absorb mainly in?

320-360 nm

water-resistant and sweat resistant?

must list a spf for both before and after being exposed to water or sweat.

any tanning product that doesnt containsunscreen:

must state this in the product.

if it takes 60 mins to get an erythema, a sunscreen with an SPF of 6 will allow stay in the sun...

6 times longer before getting the same sunburn.

labelling:

no claim should be made that implies 100% protection, reapplication is unnecessary, sunblock water proof, sweat proof.

what do compact horny layers do?

absorb and scatter UV

extra virgin olive oil:

after sun has shown to reduce ros-induced dna damage

what are some diseases associated with sun exposure?

cold sores, chicken pox, lupus and certain genetic problems can become worse with sun exposure.

what are properties of after sun products

contain a strong moisturizer and have anti-inflammatory effects (in case of erythema)

what are albinos?

albinos have defective melanocytes for which they cannot produce the molecule responsible for photoprotection. constitutive (not influenced by external factors) and facultative (due to solar radiation or hormones) skin color

what is the target of UV radiation damage?

dna, cell membrane lipids, strutural proteins and enzymes

what are vitamins and other antioxidants for

an oxygen radical scavenger

what is basal cell carcinoma?

appears as a small shiny fleshy nodule on exposed parts of the body, it grows slowly and rarely spreads to other parts of the body, it can severely damage surrounding skin and if diagnosed early has a high cure rate.

aloe:

appears to have a restorative activity against uvb-induced immune suppression

what are the 3 main types of skin cancer?

basal cell, squamous cell and melanoma

why is UVB more carinogenic than UVA?

because of its ability to damage DNA.

2 Meds =

bright erythema

use sunscreens

broad spectrum protects against both uva and uvb. other products protect only against uvb, thought to be the only damaging type.

what do endogenous body antioxidants include?

carotenoid pigments, urocanic acid and SOD

what is skin color determined by?

carotenoids and most importantly different types of melanin and also the way the melanin is packaged and distributed in the melanosomes.

wear sunglasses

dont go . by how dark the sunglasses are because uv protection comes from an invisible chemical applied to the lenses not from the color or darkness of th elenses

shea butter:

eliminates superficial irritation and erythema

radiation < 320 nm absorbed by the...

epidermis, while wavelengths above 320 nm enter the dermis.

if you apply half dose of the required spf30 sunscreen, you have protection

equivalent to the square root of the spf!

symptoms of sunburn?

fever, chills and nausea. it is an extremely dehydrating process.

spf is calculated based on the?

final product, not the individual ingredients.

film forming polymers (water res)

forms thick film on the skin

what are benzophenones?

in UVA organic filters, used in low concentration as they are liquid making sunscreen sticky. increased reports of allergic ocntact dermatitis.

what is avobenzone?

in UVA organic suncreen filters, unstable and necessitating frequent reapplication. incompatible with physical sunscreens. octocrylene is more stable.

what are salicylates e.g. octisalate

in uvb filters and present and more than 50% of secondary sunscreens because it has excellent safety profiles

extenders when applied to the skin,

interact with proteins on the surface of the skin to produce color which will wear off after a few days. the only color approved for extenders is dihydroxyacetone. they give skin a golden color, but these products do not offer sunscreen protection.

what is pterygium?

is it amenable to surgery but tends to recur. pterygium is likely to be caused, at least in part, by prolonged exposure to UV.

what is squamous cell carcinoma

it develops on the face, ears, lips and mouth. it begins as a red scaly patch, it has a high cure rate when detected and treated early. if left untreated, it can spread to other areas of the body and can be fatal.

why does UVB do more damage than UVA?

it does not penetrate the skin as much as uva BUT HAS MORE ENERGY

what is the function of keratinocyte melanin

it is a UV absorbing filter, a free radical scanger, dissipates UV as heat and undergoes oxidation in 300-360 nm range to produce immediate pigment darkening

what is superoxide dismutase for?

it is a oxygen radical scavenger and protects cell membrane from lipoprotein damage

how does skin cancer come about?

it is caused by too much sun, long term exposure and bad sunburns.

water-resistant suncreens:

it is desirable where sweat and water contact are common.

what about zinc oxide>?

it is finding its way into many cosmetics as the cream/gel is transparent when zinc oxide particles are in the nanometer scale.

what is cancer of the eye?

it is malignant melanoma, cancer of the yeball. it is a common location for basal cell carcinoma is on the yeyelids. there is evidence indicating that these cancers are associated with lifelong exposure to the sun

what is spf?

it is the time to produce erythema on protected skin/time to produce erythema on unprotected skin

at the outermost structure (SC), UV radiation is...

scattered and reflected by corneocytes

immune system suppression...

short periods of sun exposure can damage the immune system and make the body more susceptible to infections and cancers. immune systems in dark and light skinned people are equally affected.

there exists an inverse coorrelation between...

skin pigmentation and the incidence of sun-induced skin cances.

what is photokeratitis

it leads to severe pain and reduced vision resulting from highly reflective environments. like sunburn, photokeratitis appears a few hours after exposure and is reversible, symptoms generally disapepar within a day or two.

examples of warning statements in sunscreen:

mandatory, do not stay too long in the sun, strongly recommended warming, reapply frequently, over exposure to the sun is a serious health treat.

what is minimal erythema dose (MED)>?

med is the mininum UV radiation dose that produces clearly emarginated erythema in the irradiated site, given as a single exposure.

what are carotenoid pigments for?

membrane stabilizers and to quench oxygen radicals

cooling compounds (after sun):

menthol and camphor have a cooling effect, they soothe and alleviate the sensation of warmth and tenseness of sun-irritated skin.

what are anthranilates?

meradimates in uva organic suncreen filters have excellent safety profile and low allergenicity

phospholipid emulsifiers (water res)

mimic sebum with water-resistant properties

what are cinnamates

most popular in morethan 80% of uvb filters with an SPF containing octyl methoxycinnamate (primary sunscreens)

what does UVB radiation cause?

sunburn and skin cancer

avoid artificial tanning

tanning products, bronzers and extenders, are considered cosmetics, bronzers are made from color additives approved by FDA for cosmetic use, stian the skin when applied and can be washed off.

the higher the spf,

the more effective the sunburn.

what is melanoma

the most dangerous form of skin cancer and usually appears a s a dark brown or black lump with irregular edges, sometimes multicolored with shades of red, blue or whte. if ignored can spread to other areas., scandinavian paradox.

cover up

wear lightweight loosefitting long sleeved shirts. ost materials and colors absorb or reflect uv rays. tightly weaved clothes are the bes.t

what helps to relieve sunburn discomfort?

wet compresses and soothing lotions.

what is sunburn?

when the skin gets red if in the sun for too long. a bad reaction includes tenderness, pain, swelling and blistering of the skin.

wear a hat

with a 3-inch brim all around is ideal because it can protect areas often exposed to the sun

silicones: (water-resistant)

resist water and form thick film on the skin

what happens when melanin oxidizes?

results in immediate pigmentation upon uVA exposure

burns minimally, always tans well

10 to 15

what is titanium dioxide used for in sunscreen?

a common coloring agent in many skin care products, including cleansers and sunscreens

8 MEDs =

a blistering burn

water-in-oil emulsions:

oil resists removal by water.

where does skin cancer occur?

on parts of the body exposed to the sun most commonly on face, neck ears, forearms and hands

what is urocanic acid for?

oxidized to stabilize UV-induced oxygen radicals

4 meds =

painful sunburn

what are the concerns of zinc oxide?

penetration through the skin if the nanoparticles are less than 13 nm. the environment in which nanoparticle zinc is antibacterial but toxic to plankton.

acrylate cross polymers (water resistant)

prevent water from dissolving the sunscreen (used in tiO2 preparations)

liquid crystal gels (water resistant)

resist water (used in tiO2 preperations)

what occurs during eye damage

the sun can cause cataracts, and cataracts are one of the leading causes of blindness.

european union requires what of zinc oxide?

the term "nano" on the packaging

avoid the sun!

the uv index is a number from 0 to 10+ that indictes the amount of radiation reaching the earth's surface during the hour around noon. it is a linear scale. the higher the number, the greater the exposure.

what are organic sunscreens?

they absorb UV radiation like melanin and transform it into heat. they must be frequently reapplied to maintain protection from the sun. these are further subdivided into UVA and UVB absorbers and they are called 'chemical' sunscreens.

what are paba derivatives?

they are only in 2% of sunscreens due to allergenicity and they stain clothes

what are allergies?

they become sensitive to sun rays and reactions occur after short periods of sun exposre. bumps, hives, blisters and red blotchy areas.

what are inorganic sunscreens?

they reflect or scatter UV radiation and absorb little energy. they act longer, they are also referred to as physical suncreens.

what are the advantages of nanoparticles?

they tend to aggregate.

what is epidermal DNA excision repair for?

to repair uv-induced dna damage

rarely burns, tans profusely

under 10

fda guidance and asean sunscreen labelling:

upper spf limit is around 50 before anything above 30 offers little additional benefit and may expose users to dangerous levels of chemicals.

antioxidants (after sun):

vit e,c, carotenoids, coenzyme q10, although the effect after irritation is less obvious

failure of water-resistant sunscreens (3):

water dissolves the oily sunscreen film by interacting with the emulsifier. so it is better to minimize emulsifer (anhydrous sunscreens). rubbing removal if the sunscreen does not stick well to the skin. physical degradation e.g. water affects water-soluble ti02 leaving behind a film that lacks of ingredients required to achieve the labelled spf.