In a recent study, researchers determined that occupational exposure to glyphosate does not indicate an increased risk of developing non-Hodgkin lymphoma (NHL) or multiple myeloma (MM). The results were reported in La Medicina del Lavoro.
The study was a systemic literature review and meta-analysis of 7 studies involving NHL and 3 focused on MM. The researchers examined rates of NHL or MM based on exposure to glyphosate, as well as dose-response with glyphosate, data for which were available among 3 studies in NHL.
Across NHL studies, the meta-analysis relative risk (RR) was 1.03 (95% CI, 0.86-1.21). With MM, it was 1.04 (95% CI, 0.67-1.41).
Among NHL subtypes, with diffuse large B-cell lymphoma (DLBCL) the meta-analysis RR was 1.31 (95% CI, 0.93-1.75), with chronic lymphocytic leukemia (CLL) it was 0.85 (95% CI, 0.20-1.49), and with follicular lymphoma (FL) it was 0.82 (95% CI, 0.93-1.70).
Of the studies that evaluated NHL risk by level of exposure to glyphosate, each categorized exposure in a different manner. When evaluated using the highest category of exposure to glyphosate across these studies, the meta-analysis RR for NHL was 1.49 (95% CI, 0.37-2.61).
The researchers concluded that occupational exposure to glyphosate was not associated with an enhanced risk of NHL or MM, but a slight trend was shown for DLBCL with exposure, which the researchers suggested merited replication. FL and CLL showed no association with glyphosate exposure in this study.
“The suggestion of an association between glyphosate exposure and risk of NHL came from small studies that suffered from publication and possibly other forms of bias; better-designed studies that were recently reported did not confirm the results of the earlier studies,” the researchers wrote in their report.
Donato F, Pira E, Ciocan C, Boffetta P. Exposure to glyphosate and risk of non-Hodgkin lymphoma and multiple myeloma: an updated meta-analysis. Med Lav. 2020;111(1):63-73. doi:10.23749/mdl.v111i1.8967