A Systematic Review and Meta-Analysis of Glyphosate-Based Herbicide Exposure and Risk of Non-Hodgkin Lymphoma

Glyphosate-based herbicides are widely used agricultural chemicals. Concerns regarding carcinogenicity, particularly non-Hodgkin lymphoma (NHL), persist. We conducted a systematic review and meta-analysis to better evaluate glyphosate exposure and NHL risk. MEDLINE and EMBASE were searched for eligible cohort, case–control, and pooled studies. Risk of bias was assessed using recommended criteria. Random- and fixed-effects meta-analyses were performed, with sensitivity analyses addressing overlapping cohorts, hazard ratio inclusion, exposure definitions, and model overfitting. Evidence certainty was graded using GRADE. Ten primary datasets were analyzed. Ever-exposure was associated with an odds ratio of 1.11. Highest-exposure analyses demonstrated a significant association with NHL. Ever-exposure associations were modest, whereas a higher glyphosate exposure was consistently associated with an increased NHL risk. The findings were robust across sensitivity analyses.