Systematic Review: Association of Pesticide Exposure and Child Wheeze and Asthma

Abstract

Background: The prevalence of wheeze and asthma has risen over recent decades for all age groups, especially children. These disorders can lead to decreased quality of life, missed school, urgent care and emergency department visits, hospitalizations, and increased health care costs. En-vironmental exposures, including pesticide exposure, are likely a contributing factor to this in-creased prevalence. Objective: To evaluate the association of pesticide exposure with childhood wheeze and asthma. Methods: We conducted a systematic review evaluating studies of pesticide exposure (measured objectively) and child respiratory outcomes. We searched PubMed, Embase (Elsevier), CINAHL (EBSCO), Scopus (Elsevier), Cochrane Database of Systematic Reviews (Wiley), and ClinicalTri-als.gov from 1988 - 2021. Main search keywords included “pesticides”, “insecticides”, “herbi-cides”, “respiratory”, “asthma” and “wheeze”. Results: Out of 5767 studies, 25 met the inclusion criteria; eight evaluated prenatal pesticide expo-sure (n=8407), twelve evaluated postnatal exposures (n= 50,488), and five evaluated pre-and post-natal exposures (n=20,919). Main pesticides investigated were dichlorodiphenyldichloroethylene (DDE) (14 studies) followed by organophosphates (7 studies). Primary methods of outcome as-sessment were questionnaire-based (84%), followed by spirometry (16%), registry data, and blood measures. Studies varied in the strength of evidence relating to study design and measures. Most studies (84%) reported a positive association of exposure with adverse child respiratory health. Conclusion: The studies suggest an association of pesticide exposure and childhood wheeze and asthma. The varying results and methods reinforce the need for more research and standardized ap-proaches to these studies to confirm the suggested association of pesticide exposure and childhood wheeze and asthma.