A review of the effects of pesticides on human health in developing Countries

Abstract

This study focuses on the correlation between pesticide usage and human health in developing countries, particularly in Tanzania. Despite accounting for only a quarter of global pesticide consumption, developing nations bear an overwhelmingly large share of pesticide-related deaths (99% of global fatalities). The escalation of pesticide usage by 50% since the 1990s necessitates a closer examination of potential detrimental effects. The research delves into the multifaceted repercussions of pesticides on health, encompassing areas such as infant mortality, respiratory symptoms, cognitive impairment, and cancer risks. A key aspect of the study is the evaluation of methodologies employed in selected research, with an emphasis on their pertinence and feasibility within the context of developing countries. The study distinguishes between two overarching approaches to comprehending the effects of pesticides. Firstly, general approaches establish causal connections between pesticide applications and broader health outcomes by analysing changes in parameters within populations exposed to pesticides. Notably, the study discusses research on the correlation between Dichlorodiphenyltrichloroethane (DDT) usage and infant mortality rates in the US, as well as investigations into the impact of pyrethroid-treated mosquito nets on pregnancy outcomes in Uganda. Secondly, the study explores specific approaches that scrutinize pesticide effects on health outcomes through parameters like neurobehavioral performance and urinary pesticide metabolite concentrations. The study delves into two case studies that centre on the neurobehavioral performance effects resulting from pesticide exposure. The methodology involves assessing various neurobehavioral domains in children and adolescents, utilizing linear regression and mixed models. The findings reveal adverse effects on neurobehavioral development during periods of intense pesticide application. The study proposes that the methodologies presented can offer guidance to researchers in developing countries, providing adaptable and comprehensive frameworks for evaluating pesticide effects. It underscores the importance of refining methodologies to enhance their robustness, establish causal relationships, and address limitations. Additionally, the study explores the urinary biomarker approach, which examines the impacts of pesticides on respiratory health and sperm quality. It cites studies from France, Poland, and China that employ urine biomarkers to assess pesticide exposure and its associations with health outcomes. For researchers in developing countries, the study recommends adopting urine biomarker approaches to examine pesticide effects on health, particularly in situations where data on pesticide application is scarce. It suggests integrating quasi-experiments or natural experiments to bolster methodological robustness. Furthermore, the study highlights the significance of larger sample sizes and meticulous participant selection to ensure valid results. Lastly, it advocates considering cultural practices that could influence exposure patterns and employing control groups to draw causal inferences.

Date of Award	7 Sept 2023
Original language	English
Awarding Institution	University of Namur
Supervisor	Francois LIBOIS (Supervisor) & Stephanie Weynants (Co-Supervisor)