The usage of insecticides and their health impacts on farmers and farmworkers: a scoping review

Objective This scoping review was conducted to identify studies on insecticide usage practices, the types of health impacts experienced, and the factors contributing to insecticide exposures among farmers and farm workers. Methods Four electronic databases – Web of Sciences, Medline, PubMed and Scopus – were used to search relevant peer-reviewed studies published between 2011 and 2021 that reported on farmer/farmworkers’ insecticide usage and health impacts resulting from exposure. The extracted studies were then assessed against eligibility criteria to provide the final studies considered in this scoping review. Results The initial search result of 2123 articles yielded 177 studies; the majority reporting on acute rather than chronic health impacts. Approximately three quarters of the studies were conducted in less developed countries, 50% in Asia, 15% in Africa and 12% in South America. The predominant acute effects were found to be headache and irritation of skin and eyes, whereas chronic effects were more commonly cancer, reproductive/developmental or neurological. Inadequate use of personal protective equipment (PPE) was one of the major factors contributing to insecticide exposure, reported in 70 (40%) peer-reviewed articles in this review. Conclusions This review identified the major contributory factors to insecticide exposure and harm to health. It highlighted the need for further research on impediments to the safe use of insecticides and mitigation of health risks, which need to be addressed for safe insecticide application in agriculture.