Ocular symptoms and tear film break up time (BUT) among junior high school students in Penang, Malaysia - Associations with fungal DNA in school dust

Int J Hyg Environ Health. 2017 Jun;220(4):697-703. doi: 10.1016/j.ijheh.2017.01.016. Epub 2017 Feb 22.

Abstract

Background: There are few studies on ocular effects of indoor mould exposure in schools, especially in the tropics OBJECTIVE: To study associations between eye symptoms and tear film break up time (BUT) in students and demographic data and fungal DNA in schools.

Methods: A school environment study was performed among randomly selected students in eight randomly selected secondary schools in Penang, Malaysia. Information on eye symptoms and demographic data was collected by a standardised questionnaire. BUT was measured by two methods, self-reported BUT (SBUT) and by the non-invasive Tearscope (NIBUT). Dust was collected by vacuuming in 32 classrooms and analysed for five fungal DNA sequences. Geometric mean (GM) for total fungal DNA was 7.31*104 target copies per gram dust and for Aspergillus/Penicillium DNA 3.34*104 target copies per gram dust. Linear mixed models and 3-level multiple logistic regression were applied adjusting for demographic factors.

Results: A total of 368 students (58%) participated and 17.4% reported weekly eye symptoms the last 3 months. The median SBUT and TBUT were 15 and 12s, respectively. Students wearing glasses (OR 2.41, p=0.01) and with a history of atopy (OR=2.67; p=0.008) had more eye symptoms. Girls had less eye symptoms than boys (OR=0.34; p=0.006) Indoor carbon dioxide in the classrooms was low (range 380-720ppm), temperature was 25-30°C and relative air humidity 70-88%. Total fungal DNA in vacuumed dust was associated with shorter SBUT (4s shorter per 105 target copies per gram dust; p=0.04) and NIBUT (4s shorter per 105 target copies per gram dust; p<0.001). Aspergillus/Penicillium DNA was associated with shorter NIBUT (5s shorter per 105 target copies per gram dust; p=0.01).

Conclusion: Fungal contamination in schools in a tropical country can be a risk factor for impaired tear film stability among students.

Keywords: Eye symptoms; Fungal DNA; Mould; School environment; Tear film break up time (BUT).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Air Pollution, Indoor / analysis*
  • Aspergillus / genetics
  • DNA, Fungal / analysis*
  • Dust / analysis*
  • Eye Diseases / diagnosis
  • Eye Diseases / epidemiology
  • Eye Diseases / etiology*
  • Female
  • Humans
  • Malaysia / epidemiology
  • Male
  • Penicillium / genetics
  • Schools
  • Students
  • Tears*

Substances

  • DNA, Fungal
  • Dust