title: Cosmetic product migration onto the ocular surface: exacerbation of migration after eyedrop instillation.
abstract: OBJECTIVE
  Cosmetic product application may be an etiologic risk factor for dry eye syndrome. This study aimed to investigate whether a cosmetic product material (CPM) could migrate onto the ocular surface and whether eyedrop instillation might exacerbate this migration.
  
  
  METHODS
  CPM was prepared by mixing equal volumes of hydroxyethyl cellulose gel (Scopisol; Senju Pharmaceutical Co. Ltd., Osaka, Japan) and a 10% fluorescein solution. Seventy-five female volunteers were randomly separated into three groups: the outer eyelash line group, in which CPM was applied on the upper and lower eyelids approximately 2 mm from the eyelash line; the eyelash line (EL) group, in which CPM was applied close to the eyelash line but without touching it; and the inner eyelash line group, in which CPM was applied on the eyelash line extending to the margin of the eyelids. The right eye was used for this study. At 5 and 30 minutes after CPM application, slit-lamp examination was carried out to detect fluorescence, an indication of CPM migration and contamination of the ocular surface. A strip of Schirmer test paper was used to collect tears, and the color of the paper was scored (contamination score: 0-5) to determine the relative quantity of CPM contamination on the ocular surface. In another set of experiments, 5 minutes after CPM application, one drop of balanced saline solution was instilled into the eye. Thirty seconds later, eyes were examined by slit-lamp microscopy and tears were collected to determine the migration percentage (eyes with CPM migration/total eyes) and contamination score.
  
  
  RESULTS
  At 5 minutes after CPM application, the inner eyelash line group displayed a significantly higher migration percentage (96%) and average contamination score (3.35 ± 0.77) compared with the outer eyelash line (12%; 0.15 ± 0.34) and EL (20%; 0.35 ± 0.32) groups. At 30 minutes, both the migration percentage and the average contamination score increased remarkably in the EL group (60% and 2.71 ± 1.01). The migration percentage and average contamination score in the outer eyelash line group (P = 0.005 and P = 0.003, respectively) and EL group (P = 0.009 and P = 0.006, respectively) were significantly higher after eyedrop instillation compared with values before eyedrop instillation.
  
  
  CONCLUSIONS
  CPM can migrate onto the ocular surface when applied close to the eyelid margin. This migration increases with time and can be exacerbated by eyedrop instillation.
authors.affiliation: Department of Ophthalmology, Takanoko Hospital, Matsuyama, Ehime, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Goto
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zheng
authors.forename: Lindsay
authors.initials: L
authors.lastname: Gibbon
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ohashi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001692:Biological Transport; D002482:Cellulose / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D003228:Conjunctiva / Q000378:metabolism; D003315:Cornea / Q000378:metabolism; D003358:Cosmetics / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004338:Drug Combinations; D005143:Eyelids / Q000378:metabolism*; D005260:Female; D019793:Fluorescein / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006801:Humans; D008875:Middle Aged; D013666:Tears / Q000378:metabolism*; D055815:Young Adult
chemical_list: D003358:Cosmetics; D004338:Drug Combinations; D002482:Cellulose; C002283:hydroxyethylcellulose; D019793:Fluorescein