Disposal of spectacles and contact lenses: Optometrist and lens wearer perspectives

Abstract

Background: The increase in global waste generation has adverse impacts on the environment. Significant volumes of waste are generated in the lifecycle of spectacles, contact lenses (CLs) and associated products, and there is a lack of published data on their disposal practices.Aim: To determine optometrists’ recommendations to their patients, and lens wearers’ practices regarding the disposal of ophthalmic lenses and associated lens products.Setting: Optometrists and lens wearers in South Africa.Methods: Surveys were distributed via online platforms to optometrists and lens wearers and paper copies of the surveys were also available. Data from both surveys were analysed using IBM SPSS version 24.Results: Responses from 353 optometrists and 603 lens wearers were analysed. Optometrists were highly likely to recommend that patients should discard their old spectacle lenses (24%), and used CLs into wastewater systems (10%), or make no recommendations on either, respectively, (16%, 12%). Lens wearers were highly likely to retain their old spectacles upon new purchase (57%) and dispose used CLs into wastewater systems (37%). Less than 20% of optometrists and lens wearers were highly likely to recommend and engage in recycling of associated ophthalmic products.Conclusion: The disposal of CLs into wastewater systems, which contributes to microplastic pollution, must be highlighted and avoided. Optometrists should incorporate disposal instructions with all products sold to patients and promote recycling. Lens wearers should also be mindful of the environmental impact of their disposal practices.Contribution: This study provides previously unknown data on ophthalmic lens disposal practices in South Africa, and emphasises the need for environmental awareness.

Thermal testing of ophthalmic lenses to establish environmental impact: Implications for sustainable waste management practices and training for healthcare professionals

“…Discarded ophthalmic lenses are likely to enter land lls as solid waste, 15 therefore, knowledge of their thermal behaviour of polymeric ophthalmic lenses would be useful in predicting thermal decomposition behaviour under typical disposal conditions. The temperatures that outdoor plastics can reach are in uenced by the ambient conditions, including sunlight, ultraviolet radiation, land ll location, as well as, the lens material properties such as thermal conduction and emissivity.…”

“…Disposal routes for ophthalmic lenses may include land ll disposal or in the case of contact lenses potentially in wastewater systems. 15,16 The latter should be strongly discouraged as the disposal of contact lenses into wastewater systems contributes to microplastic pollution. 16 Over 80% and 60% of optometrists have discarded dummy lenses and expired contact lenses, respectively, into the waste bin and 57% of spectacle wearers have disposed of spectacles likewise.…”

“…16 Over 80% and 60% of optometrists have discarded dummy lenses and expired contact lenses, respectively, into the waste bin and 57% of spectacle wearers have disposed of spectacles likewise. 15 Re ecting upon this cumulative generation of plastic waste, this study sought to determine the thermal characteristics and onset of decomposition temperatures of ophthalmic lenses to predict their thermal behaviour upon land ll disposal.…”