Sunscreen Use in Children

Educational Objectives

The goal of this program is to improve evidence-based counseling about use of sunscreen. After hearing and assimilating this program, the clinician will be better able to:

1. List the different types of skin cancer and their predisposing factors.

2. Evaluate common arguments against use of sunscreen.

3. Counsel patients on the relative safety and efficacy of different types of sunscreen.

Summary

Skin cancer: melanoma most common on lower extremities in women and on back in men; incidence of skin cancer (nonmelanoma and melanoma) increasing steadily (true increase, not in diagnosis only); melanoma prone to metastasis and potentially fatal in fifth and sixth decades of life; melanoma related to sunburn in childhood, especially if excess sun exposure continues into adulthood (incubation period required after sunburn); in 2012, Food and Drug Administration (FDA) approved labeling sunscreen as effective for preventing skin cancer (initial purpose to prevent sunburn only); basal cell carcinoma (BCC) — most common cancer in United States; does not metastasize; ultraviolet (UV) light likely acts as promoter in patients with genetic tendency (pale-skinned white population); if gene lacking, patient unlikely to develop BCC with sun exposure; sunscreen preventive; squamous cell carcinoma (SCC) — precancerous lesion actinic keratosis; second-most common skin cancer; able to metastasize; potentially serious, especially in immunocompromised patients; UV light plays major role in development, with dose-response relationship; individuals with more pigment in skin have much lower baseline and overall risk; in seventh decade of life and onward, immune surveillance decreases and multiple SCC lesions may develop

Melanoma: linked to intense intermittent sunburn; individuals who spend excessive time in sun may develop lentigo maligna (sun-induced indolent melanoma of face); superficial spreading melanoma (most common) related to sunburn and not to chronic sun exposure; nodular melanoma (eg, of ovary, fingernails) related to genetics rather than sun exposure (sunscreen not preventive), especially if aggressive

Confusion about sunscreen: article by Jacobsen (2019) contains faulty logic; online information from medical establishment and Environmental Protection Agency confirms that sunscreen prevents skin cancer and is beneficial to health, but patients confused by conflicting information; Jacobsen’s arguments — sunscreen causes vitamin D deficiency, leading to carcinogenesis and death; absorption of ingredients causes endocrine disruption and cancer; kills coral reefs

Vitamin D: UV light penetrates through sunscreen (enabling synthesis of vitamin D); UV light completely blocked only when skin covered; most individuals do not use adequate amount of sunscreen, do not apply complete coat, and do not reapply after swimming or sweating; most sunscreens not highly effective; Jacobsen’s argument based on single researcher who found sunbathers in Sweden live longer (not controlled for other factors); many studies show sunbathing and use of tanning salons increase incidence of melanoma and nonmelanoma skin cancer

Types of sunscreen: physical — favored by many parents, who fear exposing child to “chemicals”; safe and not absorbed (nanoparticles cluster in upper dermis); zinc oxide and titanium dioxide reflect UV light without interacting with skin; not allergenic; often moisturizing (beneficial for children with eczema); typically provide broad-spectrum coverage but do not block as much long-wave UV (UVA) light as chemical sunscreens; chemical — process and disperse UV energy in skin; absorbed through skin; more effective than physical sunscreens, even if not used correctly; many provide broad-spectrum coverage; all work well for short-wave UV (UVB) rays; potential cause of allergy, contact dermatitis, and irritation

Pitfalls of sunscreen use: Sun Protection Factor (SPF) indicates time person may spend in sun without burning (compared with no sunscreen); SPF 50 allows ≈2 hr in sun instead of ≈2 min in individual with pale skin (assumes correct use and ingredients working as expected); many new sunscreens not tested before going to market (efficacy unknown); sunscreen may provide false sense of security (eg, staying in sun all day without reapplication), leading to sunburn; sunscreen itself does not cause skin cancer

Systemic absorption: safety unknown; FDA has requested in-house data from industry (sunscreen regulated as over-the-counter drug); in Matta et al (2019), 24 volunteers applied sunscreen to 75% of body, 4 times daily for 4 days; all 4 active ingredients (eg, oxybenzone, avobenzone) absorbed (measurable on blood testing); safe effective sunscreens available in Europe; reliance on data from industry risks conflict of interest; sunscreens considered cosmetic in Europe (approval faster); difficult to remove from US market once approved; Sunscreen Innovation Act (2012) attempted to bring European ingredients to US more quickly, but process remains slow; zinc oxide and titanium dioxide generally regarded as safe and effective; data insufficient for 12 other ingredients; Consumer Reports tests for efficacy (many sunscreens do not meet SPF claim); Skin Cancer Foundation publishes well-researched recommendations; best sunscreens (difficult to find) combine mineral and chemical ingredients; CoTz (zinc oxide) most effective mineral-only sunscreen (pasty, expensive); avobenzone best spray formula; stick formula efficacious for children; parents typically use social media and online personalities to make decisions (information largely inaccurate); Environmental Working Group website focuses more on safety than efficacy

Oxybenzone: data insufficient to assess whether absorption causes early puberty; excellent filter for UVA rays; estrogenic and antiandrogenic in animals; easily absorbed; present in urine of ≈96% of Americans; used in other skin care products as well; found in breast milk of some women; biologic effects in humans unknown; speaker recommends avoiding use in pregnancy, while nursing, and in infants

Environmental effects of sunscreen: enters wastewater when washed off; chemicals not removed by processing (enter effluent and contact marine animals); coral reefs — Hawaii banning use of oxybenzone and other ingredients; Florida planning same ban; loss of ecosystem devastating; reefs at risk for bleaching by oxybenzone (kills coral larvae and damages adult coral in test tubes); Consumer Reports recommends Badger Active (zinc-based sunscreen); speaker believes abrupt destruction caused by global warming

Sun protection: individuals with sun-sensitive skin should avoid unprotected exposure during midday; different types of protection recommended for different skin phototypes; individuals with dark pigmentation require more UV exposure to make vitamin D; pale skin efficient at absorbing vitamin D; risk for skin cancer correlated with amount of pigmentation (risk much higher with pale skin); facial aging occurs regardless of skin type (eg, seborrheic keratosis, lentigo, wrinkling); photoprotection of face important to minimize aging (obtain vitamin D through skin of body); considerations — family history of skin cancer (first- and second-degree relatives); cultural aspects of clothing and skin exposure (eg, consider vitamin D deficiency rather than sun protection in Muslim patient wearing garments covering most of body); lifestyle; sunburn caused by light, not by heat (85% of UV light penetrates fog); organized sports; cover infants and toddlers, using zinc on exposed skin; relatively difficult with school-aged children and teenagers; school may not allow application of sunscreen; use of rash guard often easier (also avoids sunscreen washing into ocean); ask about sunbathing and tanning beds in risk-taking adolescents; use gel or alcohol-based liquid for acne-prone skin; fashionable clothing providing coverage available at surf shops (improves compliance); emphasize prevention of sunburn with teenagers (rather than hypervigilant sun protection)

Readings

Calafat AM et al: Concentrations of the sunscreen agent benzophenone-3 in residents of the United States: National Health and Nutrition Examination Survey 2003-2004. Environ Health Perspect 2008 Jul;116(7):893-7; Downs CA et al: Toxopathological effects of the sunscreen UV filter, oxybenzone (benzophenone-3), on coral planulae and cultured primary cells and its environmental contamination in Hawaii and the U.S. Virgin Islands. Arch Environ Contam Toxicol 2016 Feb;70(2):265-88; Hoel DG et al: Sun exposure public health directives. Int J Environ Res Public Health 2018 Dec 10;15(12): pii: E2794. doi: 10.3390/ijerph15122794; Jacobsen, R: Is Sunscreen the New Margarine? Outside 2019 Jan 10; Karagas MR et al: Squamous cell and basal cell carcinoma of the skin in relation to radiation therapy and potential modifications of risk by sun exposure. Epidemiology 2007 Nov;18(6):776-84; Matta MK et al: Effect of sunscreen application under maximal use conditions on plasma concentration of sunscreen active ingredients: a randomized clinical trial. JAMA 2019 Jun 4;321(21):2082-91; Passeron T et al: Sunscreen photoprotection and vitamin D status. Br J Dermatol 2019 May 8: doi: 10.1111/bjd.17992; Sánchez G et al: Sun protection for preventing basal cell and squamous cell skin cancers. Cochrane Database Syst Rev 2016 Jul 25;7: CD011161. doi: 10.1002/14651858.CD011161.pub2; Schneider SL et al: Review of environmental effects of oxybenzone and other sunscreen active ingredients. J Am Acad Dermatol 2019 Jan;80(1):266-71; Whiteman DC et al: Childhood sun exposure as a risk factor for melanoma: a systematic review of epidemiologic studies. Cancer Causes Control 2001 Jan;12(1):69-82.

Disclosures

For this program, members of the faculty and planning committee reported nothing relevant to disclose.

Acknowledgements

Dr. Howard was recorded at the 52nd Annual Advances and Controversies in Clinical Pediatrics, presented by the University of California, San Francisco, School of Medicine, and UCSF Benioff Children’s Hospital, and held May 30 to June 1, 2019, in San Francisco, CA. For information about upcoming CME conferences from the University of California, San Francisco, School of Medicine and UCSF Benioff Children’s Hospital, please visit www.ucsfpediatricadvances.com. The Audio Digest Foundation thanks the speakers and the sponsors for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

PD654002

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.