EXPOSURE TO EXPOSURE TO ULTRAVIOLET (UV) LIGHTULTRAVIOLET (UV) LIGHT

Sophie J. Balk, M.D.Sophie J. Balk, M.D.

Professor of Clinical PediatricsProfessor of Clinical PediatricsAlbert Einstein College of Medicine Albert Einstein College of Medicine

NEETFNEETFChildren’s Environmental HealthChildren’s Environmental Health

Faculty Champions InitiativeFaculty Champions Initiative

www.charlie.org

GOALS: TO DISCUSS..GOALS: TO DISCUSS.. Background on UV radiation Background on UV radiation

(UVR)(UVR) Health effectsHealth effects

•Focus on skin cancerFocus on skin cancer Prevention messagesPrevention messages What to ask in the historyWhat to ask in the history ResourcesResources

SUNLIGHTSUNLIGHT

UVR MODIFIED BY PASSAGE UVR MODIFIED BY PASSAGE THROUGH ATMOSPHERE….THROUGH ATMOSPHERE….

Stratosphere (10 - 50 Km above Stratosphere (10 - 50 Km above sea level)sea level)• Absorption by ozoneAbsorption by ozone• Scattering by moleculesScattering by molecules

Troposphere (0 -10 Km above sea Troposphere (0 -10 Km above sea level)level)• Absorption by pollutantsAbsorption by pollutants• Scattering by particulatesScattering by particulates• CloudsClouds

INCREASED UV INCREASED UV INTENSITY...INTENSITY...

At middayAt midday In summerIn summer Closer to the equatorCloser to the equator At higher altitudesAt higher altitudes Reflected from ground Reflected from ground

surfaces, sand, snow, watersurfaces, sand, snow, water

HEALTH EFFECTS OF UVRHEALTH EFFECTS OF UVR

SkinSkin EyesEyes Immune systemImmune system

AAP Pediatric Environmental Health, November 2003.

EFFECTS ON THE SKINEFFECTS ON THE SKIN Vitamin D ProductionVitamin D Production Erythema and sunburnErythema and sunburn TanningTanning Skin agingSkin aging PhotosensitivityPhotosensitivity Non-melanoma skin cancerNon-melanoma skin cancer

• Basal cell carcinoma Basal cell carcinoma • Squamous cell carcinoma Squamous cell carcinoma

MelanomaMelanoma

AAP Pediatric Environmental Health, November 2003.

American Cancer Society 2006 ( www.cancer.org)

Gilchrest et al. NEJM April 1999.

ERYTHEMA & SUNBURNERYTHEMA & SUNBURN

Minimal erythemal dose Minimal erythemal dose (MED) depends on (MED) depends on •Skin type and thicknessSkin type and thickness•Amount of melanin and ability Amount of melanin and ability

to produce melanin after to produce melanin after exposureexposure

• Intensity of the radiationIntensity of the radiation Six sun-reactive skin typesSix sun-reactive skin types

SKIN TYPES

TANNINGTANNING Protective response to sun Protective response to sun

exposureexposure Immediate tanningImmediate tanning: Induced : Induced

by UV-A, no new melaninby UV-A, no new melanin Delayed tanningDelayed tanning: Induced by : Induced by

UV-B, begins at 2-3 days, UV-B, begins at 2-3 days, peaks at 7-10 days, new peaks at 7-10 days, new melanin formedmelanin formed

NON-MELANOMA NON-MELANOMA SKIN CANCER (NMSC)SKIN CANCER (NMSC)

Basal cell carcinoma (BCC) and Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)squamous cell carcinoma (SCC)

Most common malignancies in Most common malignancies in adults: > 1,000,000/year adults: > 1,000,000/year

Found on maximally-exposed areas Found on maximally-exposed areas Usually not fatal unless untreatedUsually not fatal unless untreated Related to Related to cumulativecumulative sun exposure sun exposure

American Cancer Society 2006 ( www.cancer.org). Accessed 6-28-06.

MELANOMAMELANOMA

Most common Most common fatalfatal skin cancer skin cancer 2006: 62,190 new cases with 2006: 62,190 new cases with

7,910 deaths7,910 deaths11

Occurs in teens, young adultsOccurs in teens, young adults Metastatic melanoma has a Metastatic melanoma has a

grave prognosisgrave prognosis Prevention, early detection are Prevention, early detection are

keykey1 – American Cancer Society 2006 (www.cancer.org). Accessed 6-28-06.

MELANOMA IN YOUNG ADULTSMELANOMA IN YOUNG ADULTSAND CHILDRENAND CHILDREN

A common malignancy in whitesA common malignancy in whites11 • 22ndnd most common, women 20 – 29 most common, women 20 – 29• 33rdrd most common, men 20 - 29 most common, men 20 - 29

Melanoma in childrenMelanoma in children22

• Incidence risingIncidence rising• 33 patients 33 patients << 14; 25 yr experience 14; 25 yr experience

Presentation often atypical: most Presentation often atypical: most lesions raised, well-defined borders lesions raised, well-defined borders

Lesions unlike any other on childLesions unlike any other on child

1 - Wu et al. Cancer Causes and Control 2005; 2 - Ferrari et al, Pediatrics 2005

MELANOMA

A - AsymmetryB - BorderC - ColorD - DiameterE - Evolving

MELANOMAMELANOMA

Lifetime riskLifetime risk• 1930: 1 in 15001930: 1 in 1500• 1987: 1 in 1201987: 1 in 120• 2002: 1 in 682002: 1 in 6811

• 2010: 1 in 502010: 1 in 5011

1- Rigel DS. Dermatol Clin 2002; 20

WHY IS THE INCIDENCE OF WHY IS THE INCIDENCE OF MELANOMA RISING?MELANOMA RISING?

Thought to be related to sun Thought to be related to sun exposureexposure• Depletion of the ozone layerDepletion of the ozone layer• Changing patterns of dressChanging patterns of dress• More leisure timeMore leisure time• ““Sun culture”Sun culture”

Pediatric Environmental Health. AAP 2003

SUNLIGHT AND MELANOMASUNLIGHT AND MELANOMA

Epidemiologic and biological Epidemiologic and biological evidence implicate sunlight evidence implicate sunlight in the pathogenesis of in the pathogenesis of melanomamelanoma

Pediatric Environmental Health. AAP 2003

SUNLIGHT AND MELANOMASUNLIGHT AND MELANOMA

LatitudeLatitude Race and pigmentation Race and pigmentation Childhood exposureChildhood exposure NeviNevi

Pediatric Environmental Health. AAP 2003

CHILDHOOD EXPOSURECHILDHOOD EXPOSURE

~25% of lifetime sun exposure ~25% of lifetime sun exposure occurs during childhood and occurs during childhood and adolescenceadolescence11

Episodic high exposures Episodic high exposures sufficient to cause sunburn, sufficient to cause sunburn, particularly in childhood and particularly in childhood and adolescence, increase the risk of adolescence, increase the risk of melanomamelanoma22

1- Godar et al. Photochem Photobiol 2003 2 -Elwood, Jopson. Int J Cancer 1997;73

CHILDHOOD EXPOSURECHILDHOOD EXPOSURE

Migration studies: High sun Migration studies: High sun exposure during childhood is exposure during childhood is important in the pathogenesis of important in the pathogenesis of melanomamelanoma11

1 - Khlat et al. Am J Epidemiol. 1992;135

NEVINEVI

Acute sun exposure is implicated Acute sun exposure is implicated in the development of nevi in in the development of nevi in childrenchildren11

There is a relationship between There is a relationship between the number and type of nevi and the number and type of nevi and the development of melanomathe development of melanoma11

Dysplastic nevi: precursor Dysplastic nevi: precursor lesions that increase risklesions that increase risk22

1 – Gallagher et al. Arch Dermatol. 1990; 126 2 - Clark. Arch Dermatol. 1988;124

BIOLOGIC EVIDENCEBIOLOGIC EVIDENCE

UVB exposure UVB exposure DNA lesions DNA lesions (pyrimidine dimers) whose (pyrimidine dimers) whose incomplete repair leads to incomplete repair leads to mutationsmutations11

UVA causes oxidative damage to UVA causes oxidative damage to DNA DNA mutations mutations11

UVR contributes to immune UVR contributes to immune suppressionsuppression22

1 - Gilchrest et al. N Engl J Med. 1999;340 2 – Strickland, Kripke. Clin Plast Surg. 1997;24

BIOLOGIC EVIDENCE: XPBIOLOGIC EVIDENCE: XP

Xeroderma pigmentosum (XP): Xeroderma pigmentosum (XP): Grossly deficient repair of DNA Grossly deficient repair of DNA damaged by UVRdamaged by UVR11

SCC, BCC and melanoma seen SCC, BCC and melanoma seen beginning at young agesbeginning at young ages11

1 - Photosensitivity. In Behrman, Kliegman, Jenson, eds. Nelson Textbook of Pediatrics. 16th ed. Philadelphia, PA: WB Saunders Co; 2000:1998-2001

SUN PROTECTIONSUN PROTECTION

Sun protection is recommended Sun protection is recommended to prevent skin cancer, including to prevent skin cancer, including melanomamelanoma

Sun protection is recommended Sun protection is recommended beginning early in lifebeginning early in life

Pediatric clinicians may play an Pediatric clinicians may play an important role in delivering important role in delivering messagesmessages

Pediatric Environmental Health. AAP 2003

PREVENTION AT ALL PREVENTION AT ALL DEVELOPMENTAL STAGES DEVELOPMENTAL STAGES

InfantsInfants• Lack mobilityLack mobility• Skin has less melanin than at any Skin has less melanin than at any

other time other time ChildrenChildren

• New patterns of exposureNew patterns of exposure AdolescentsAdolescents

• Susceptible to society’s ideas about Susceptible to society’s ideas about beauty and healthbeauty and health

UV LIGHT – UV LIGHT – PREVENTION MESSAGES PREVENTION MESSAGES

Do not burn; avoid sun tanning and Do not burn; avoid sun tanning and tanning beds tanning beds

Generously apply sunscreen Generously apply sunscreen Wear protective clothing Wear protective clothing Seek shadeSeek shade Use extra caution near water, snow Use extra caution near water, snow

and sandand sand www.skincancerprevention.org/Tips/tabid/www.skincancerprevention.org/Tips/tabid/

54/ Default.aspx54/ Default.aspx

DO NOT BURN; AVOID SUN DO NOT BURN; AVOID SUN TANNING AND TANNING BEDSTANNING AND TANNING BEDS

Burning raises melanoma riskBurning raises melanoma risk Avoid/limit exposure during Avoid/limit exposure during

peak hours (10AM – 4PM) peak hours (10AM – 4PM) Avoid intentional tanningAvoid intentional tanning

GENEROUSLY APPLY SUNSCREENGENEROUSLY APPLY SUNSCREEN

Sunscreen is the sun protection Sunscreen is the sun protection method most commonly usedmethod most commonly used11

Apply to all exposed skin using Apply to all exposed skin using SPF SPF >> 15 15

Broad protection (UVA & UVB) Broad protection (UVA & UVB) Reapply often Reapply often

1 - Olson et al. Pediatrics 1997;99

WEAR PROTECTIVE CLOTHING WEAR PROTECTIVE CLOTHING

Simple, practical protectionSimple, practical protection The structure (weave) of the The structure (weave) of the

fabric is most importantfabric is most important Light-weight long pants and Light-weight long pants and

sleeves suggested sleeves suggested Hats with a bill or brimHats with a bill or brim SunglassesSunglasses

SEEK SHADESEEK SHADE

Shade is useful but…Shade is useful but… Shade offers insufficient Shade offers insufficient

protection because UV light protection because UV light is scattered and reflectedis scattered and reflected•A fair-skinned person sitting A fair-skinned person sitting

under a tree can burn in an under a tree can burn in an hourhour

SUNSCREENSSUNSCREENS

Came into use in 1950’sCame into use in 1950’s Promoted tanning without Promoted tanning without

burningburning First true sunscreen (PABA) First true sunscreen (PABA)

became available in 1970’sbecame available in 1970’s High-intensity sunscreens within High-intensity sunscreens within

last 15 yearslast 15 years

Rigel DS. Dermatol Clin 2002; 20.

OPAQUE SUNSCREENSOPAQUE SUNSCREENS

Scatter, reflect, block UV lightScatter, reflect, block UV light Zinc oxide, titanium dioxide, red Zinc oxide, titanium dioxide, red

vetenary petrolatum, talcvetenary petrolatum, talc Effective for diseases related to Effective for diseases related to

light exposure (SLE, XP, solar light exposure (SLE, XP, solar urticaria)urticaria)

Useful for those spending Useful for those spending extensive periods outsideextensive periods outside

Rigel DS. Dermatol Clin 2002; 20.

CHEMICAL SUNSCREENSCHEMICAL SUNSCREENS

Protection RangeProtection Range

PABAPABA 260 – 313260 – 313

Octyl methoxy-Octyl methoxy-cinnamatecinnamate

280 – 310280 – 310

OxybenzoneOxybenzone 270 – 350 270 – 350

ParsolParsol 310 – 400 310 – 400

Rigel DS. Dermatol Clin 2002; 20.UVB: 290 – 320 nmUVA: 320 – 400 nm

SUN PROTECTION FACTOR - SUN PROTECTION FACTOR - SPF SPF

Ratio of amount of time to sunburn Ratio of amount of time to sunburn with with sunscreen compared to time to sunscreen compared to time to sunburn sunburn withoutwithout sunscreen sunscreen

1970’s: SPF’s 2 – 4: 1970’s: SPF’s 2 – 4: 50 – 75% protection 50 – 75% protection

High-potency sunscreens: High-potency sunscreens: SPF’s 15 – 50, 93 – 98% protectionSPF’s 15 – 50, 93 – 98% protection

Rigel DS. Dermatol Clin 2002; 20.

LIMITATIONS OF SPF SYSTEMLIMITATIONS OF SPF SYSTEM

Applies to UVB protection onlyApplies to UVB protection only Measured under ideal conditionsMeasured under ideal conditions Concerns about: Concerns about:

• Using adequate amountsUsing adequate amounts• Applying before neededApplying before needed• Need for frequent reapplicationNeed for frequent reapplication

SUNSCREEN AND MELANOMASUNSCREEN AND MELANOMA

Sunscreen Sunscreen • Reduces sunburnReduces sunburn• Can prevent actinic keratosesCan prevent actinic keratoses11

• Can prevent SCCCan prevent SCC22 No conclusive data in humans to No conclusive data in humans to

demonstrate that sunscreen demonstrate that sunscreen prevents melanoma or BCCprevents melanoma or BCC

1 - Thompson, Jolley, Marks. NEJM 1993; 3292 – Green et al. Lancet 1999; 354

IS SUNSCREEN USE A RISK IS SUNSCREEN USE A RISK FACTOR FOR MELANOMA?FACTOR FOR MELANOMA?

Swedish case-control study Swedish case-control study found increased riskfound increased risk11

Several studies found increased Several studies found increased risk with sunscreen use; some risk with sunscreen use; some studies found decreased risk; studies found decreased risk; others found no changeothers found no change22

1 – Westerdal et al. Melanoma Res 1995; 5:59-65. 2 - Cooper, Lim. J Amer Acad Dermatol 1999; 40.

IS SUNSCREEN USE A RISK IS SUNSCREEN USE A RISK FACTOR FOR MELANOMA?FACTOR FOR MELANOMA?

No studies demonstrate that No studies demonstrate that sunscreens are carcinogenicsunscreens are carcinogenic11

Sunscreen users may extend Sunscreen users may extend their time out in the suntheir time out in the sun22

There may be greater exposure There may be greater exposure to UVAto UVA11

1-Cooper, Lim. J Amer Acad Dermatol 1999; 402-Autier et al. J Natl Cancer Inst. 1999;91:1304-1309

SUNSCREEN MAKERS SUED SUNSCREEN MAKERS SUED FOR MISLEADING CLAIMSFOR MISLEADING CLAIMS

April 2006: 9 suits involving April 2006: 9 suits involving popular brands charged that popular brands charged that manufacturers inflated claims manufacturers inflated claims about sunscreens’ protection about sunscreens’ protection

Sunscreen called the “snake oil Sunscreen called the “snake oil of the 21st century“of the 21st century“

Focus on labels claiming equal Focus on labels claiming equal UVA/UVB protection; “all day”; UVA/UVB protection; “all day”; “waterproof”; “waterproof”;

www.consumeraffairs.com/news04/2006/03/sunscreen.html. Accessed 7-29-06

RECOMMENDATIONSRECOMMENDATIONS

AAP, ACS, AAD, EPA, CDC, others AAP, ACS, AAD, EPA, CDC, others recommend multi-component recommend multi-component message message

Sunscreen is one part of a sun Sunscreen is one part of a sun protection programprotection program

Sunscreen should not be used to Sunscreen should not be used to extend time spent in the sunextend time spent in the sun

SUNSCREEN AND VITAMIN D SUNSCREEN AND VITAMIN D METABOLISMMETABOLISM

Vitamin D produced in the skin Vitamin D produced in the skin by action of UVBby action of UVB

Inadequate sunlight is an Inadequate sunlight is an important risk factor for ricketsimportant risk factor for rickets

Concerns that sunscreen use Concerns that sunscreen use may affect levels of Vitamin Dmay affect levels of Vitamin D

SUNSCREEN AND VITAMIN D SUNSCREEN AND VITAMIN D METABOLISMMETABOLISM

AAP policy - April 2003AAP policy - April 2003 Infants need 200 IU Vit D/dayInfants need 200 IU Vit D/day Human milk: Human milk: << 25 IU/L Vit D 25 IU/L Vit D Infant formula: 400 IU/L Vit DInfant formula: 400 IU/L Vit D Supplementation: all breast-fed Supplementation: all breast-fed

infants, formula-fed infants infants, formula-fed infants taking <500 ml/day, children taking <500 ml/day, children with inadequate intake/sunwith inadequate intake/sun

AAP Section on Breastfeeding and Committee on Nutrition. Pediatrics 2003; 111.

VITAMIN D VITAMIN D AND CANCER PREVENTIONAND CANCER PREVENTION

Recent studies suggest a role for Recent studies suggest a role for vitamin D in cancer preventionvitamin D in cancer prevention• Colon, breast, prostate, lung Colon, breast, prostate, lung

High prevalence of vitamin D High prevalence of vitamin D deficiency/insufficiency deficiency/insufficiency

Insufficient evidence to make Insufficient evidence to make recommendations about sun recommendations about sun exposure exposure

http://msnbc.msn.com/id/7875140/print/1/displaymode/1098. Accessed 7-04-06

People Magazine May 05

                                                      

INDOOR TANNINGINDOOR TANNING11

Salon use in <25 year oldsSalon use in <25 year olds• 1996 - 8%; 2003 - 26%1996 - 8%; 2003 - 26%

College students: 32% – 55% College students: 32% – 55% usage ratesusage rates

High school studentsHigh school students• Males 6 - 44% Males 6 - 44% • Females 20 – 70%Females 20 – 70%

2001: Indoor tanning industry 2001: Indoor tanning industry generated $4 billion in revenuesgenerated $4 billion in revenues

1 - Scientific and regulatory issues related to indoor tanning. JAAD 2004.

INDOOR TANNING AND INDOOR TANNING AND MELANOMAMELANOMA

Epidemiologic evidence suggests Epidemiologic evidence suggests that indoor tanning causes that indoor tanning causes melanoma and SCC; perhaps melanoma and SCC; perhaps BCCBCC11

NIEHS recommends that UV light NIEHS recommends that UV light from artificial sources such as from artificial sources such as tanning booths and tanning beds tanning booths and tanning beds be listed as a known human be listed as a known human carcinogencarcinogen22

1 - Scientific and regulatory issues related to indoor tanning. JAAD 20042 - http://www.nih.gov/news/pr/oct97/niehs-30.htm. Accessed 7-04-06

INDOOR TANNING LEGISLATIONINDOOR TANNING LEGISLATION

Federal regulation of Federal regulation of manufacturers manufacturers

States regulate operation of States regulate operation of equipment equipment

26 states regulate salon 26 states regulate salon operatorsoperators• Legislation variesLegislation varies• Limited enforcement Limited enforcement

http://news.findlaw.com/prnewswire/20050317/17mar2005164738.html

ARE SUN PROTECTION ARE SUN PROTECTION MESSAGES EFFECTIVE?MESSAGES EFFECTIVE?

Melanoma rates rising quicklyMelanoma rates rising quickly Geller et al: Nationwide survey Geller et al: Nationwide survey

of > 10,000 teens 12 - 18of > 10,000 teens 12 - 18• 83%: 83%: >>1 sunburns in previous 1 sunburns in previous

summersummer• 36%: 36%: >>3 sunburns3 sunburns• Sunscreen use in 34%Sunscreen use in 34%• ~ 10% reported tanning bed use in ~ 10% reported tanning bed use in

previous yearprevious year

Geller et al. Pediatrics 2002.

UV LIGHT - HISTORYUV LIGHT - HISTORY

Family history of melanoma?Family history of melanoma? Are you (your child) protected Are you (your child) protected

from excess sun exposure?from excess sun exposure? Do you visit tanning parlors? Do you visit tanning parlors? Target children at high riskTarget children at high risk

• Family history of melanomaFamily history of melanoma• Skin Types I & IISkin Types I & II• Nevi, frecklingNevi, freckling• Sunburns Sunburns

UV LIGHT – UV LIGHT – PREVENTION MESSAGES PREVENTION MESSAGES

Do not burn; avoid sun tanning and Do not burn; avoid sun tanning and tanning beds tanning beds

Generously apply sunscreen Generously apply sunscreen Wear protective clothing Wear protective clothing Seek shadeSeek shade Use extra caution near water, snow Use extra caution near water, snow

and sandand sand Early detection is also recommendedEarly detection is also recommended

www.skincancerprevention.org/Tips/tabid/54/ Default.aspx

RESOURCES RESOURCES

Ultraviolet IndexUltraviolet Index EPA SunWise Program: EPA SunWise Program:

www.epa.gov/sunwisewww.epa.gov/sunwise CDC “Choose Your Cover” CDC “Choose Your Cover”

campaign: campaign: www.cdc.gov/ChooseYourCoverwww.cdc.gov/ChooseYourCover

National Council on Skin Cancer National Council on Skin Cancer Prevention: Prevention: www.skincancerprevention.orgwww.skincancerprevention.org

Pediatric EnvironmentalHealth, November 2003

RESOURCES

THANK YOU!

Contact InformationContact InformationLeyla Erk McCurdyLeyla Erk McCurdySenior Director, Health & EnvironmentSenior Director, Health & EnvironmentNational Environmental Education & Training National Environmental Education & Training

Foundation (NEETF)Foundation (NEETF)Email: mccurdy@neetf.orgEmail: mccurdy@neetf.orgPhone: 202.261.6488Phone: 202.261.6488

NEETF is tracking pediatric environmental healthNEETF is tracking pediatric environmental healtheducation activities for health care providers and education activities for health care providers and

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