title: FDA-sunlamp recommended Maximum Timer Interval And Exposure Schedule: consensus ISO/CIE dose equivalence.
abstract: The authors compared calculations of sunlamp maximum exposure times following current USFDA Guidance Policy on the Maximum Timer Interval and Exposure Schedule, with USFDA/CDRH proposals revising these to equivalent erythemal exposures of ISO/CIE Standard Erythema Dose (SED). In 2003, [USFDA/CDRH proposed replacing their unique CDRH/Lytle] erythema action spectrum with the ISO/CIE erythema action spectrum and revising the sunlamp maximum exposure timer to 600 J m(-2) ISO/CIE effective dose, presented as being biologically equivalent. Preliminary analysis failed to confirm said equivalence, indicating instead ∼38% increased exposure when applying these proposed revisions. To confirm and refine this finding, a collaboration of tanning bed and UV lamp manufacturers compiled 89 UV spectra representing a broad sampling of U.S. indoor tanning equipment. USFDA maximum recommended exposure time (Te) per current sunlamp guidance and CIE erythemal effectiveness per ISO/CIE standard were calculated. The CIE effective dose delivered per Te averaged 456 J(CIE) m(-2) (SD = 0.17) or ∼4.5 SED. The authors found that CDRH's proposed 600 J(CIE) m(-2) recommended maximum sunlamp exposure exceeds current Te erythemal dose by ∼33%. The current USFDA 0.75 MED initial exposure was ∼0.9 SED, consistent with 1.0 SED initial dose in existing international sunlamp standards. As no sunlamps analyzed exceeded 5 SED, a revised maximum exposure of 500 J(CIE) m(-2) (∼80% of CDRH's proposal) should be compatible with existing tanning equipment. A tanning acclimatization schedule is proposed beginning at 1 SED thrice-weekly, increasing uniformly stepwise over 4 wk to a 5 SED maximum exposure in conjunction with a tan maintenance schedule of twice-weekly 5 SED sessions, as biologically equivalent to current USFDA sunlamp policy.
authors.affiliation: Rapid Precision Testing Laboratories, Cordova, TN, USA. RPTLDowdy@aol.com
authors.forename: John C
authors.initials: JC
authors.lastname: Dowdy
authors.forename: Eugene A
authors.initials: EA
authors.lastname: Czako
authors.forename: Michael E
authors.initials: ME
authors.lastname: Stepp
authors.forename: Steven C
authors.initials: SC
authors.lastname: Schlitt
authors.forename: Gregory R
authors.initials: GR
authors.lastname: Bender
authors.forename: Lateef U
authors.initials: LU
authors.lastname: Khan
authors.forename: Kenneth D
authors.initials: KD
authors.lastname: Shinneman
authors.forename: Manuel G
authors.initials: MG
authors.lastname: Karos
authors.forename: James G
authors.initials: JG
authors.lastname: Shepherd
authors.forename: Robert M
authors.initials: RM
authors.lastname: Sayre
mesh_terms: D006801:Humans; D017410:Practice Guidelines as Topic; D011829:Radiation Dosage; D011835:Radiation Protection / Q000331:legislation & jurisprudence / Q000379:methods* / Q000592:standards; D011839:Radiation, Ionizing; D012867:Skin / Q000528:radiation effects*; D055108:Sunbathing; D013997:Time Factors; D014481:United States; D014486:United States Food and Drug Administration