Food Contaminants
glyphosate causes non-Hodgkin lymphoma
In plain terms: Does glyphosate cause non-Hodgkin lymphoma?
Contested Food Contaminants 💰 Industry COI noted🔬 Includes disconfirming
Part of: 🔍 glyphosate
RefutedContestedStrong support
consensus score 0.01
Unresolved. Ever being exposed shows no clear added risk; a modestly higher risk appears only in the most heavily exposed farm applicators, and the largest long-term study found none. No study has looked at glyphosate in food.
📅 Last reviewed: 2026-07-29 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
5 support 2 contradict 1 tested null 4 mixed · 12 sources, 5 independent groups
What the evidence shows
The most contested claim in the hub, and the detail resolves the apparent deadlock better than the public fight does. Every major meta-analysis from 2016 onward shows the same shape: a clean or near-clean null for EVER having been exposed, with elevated risk of roughly 1.3 to 1.5 confined to the highest cumulative-exposure applicators.
The evidence (14)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Weisenburger DD 2026 · Clinical lymphoma, myeloma & leukemia | observational | supports | low | Narrative review (not a systematic pooling exercise), OCCUPATIONAL-exposure focus, arguing that recent epidemiologic, animal, and mechanistic studies (including a new rat carcinogenicity study and genotoxicity data) provide 'consistent, coh |
| Gagnier JJ et al 2026 · medRxiv | meta-analysis | mixed | moderate | OCCUPATIONAL/agricultural exposure meta-analysis (17 publications, 10 primary datasets: cohort + case-control + pooled analyses); ever-exposure OR=1.11 (95% CI 0.98-1.27, I2~53%) was null, but highest-exposure OR~1.38 (95% CI 1.00-1.90, I2~ |
| Donato F, Pira E, Ciocan C, Boffetta P 2020 · La Medicina del lavoro | meta-analysis | contradicts | moderate | Occupational-exposure meta-analysis (7 non-overlapping NHL studies, 1271 exposed cases; Leon 2019 pooled AGRICAN/CNAP/AHS = 74% of weight): ever-exposure meta-RR 1.03 (95% CI 0.86-1.21, I2=0%); highest exposure category 1.49 (0.37-2.61; only 3 studies, driven by two small case-controls, AHS top quartile 0.78, 0.58-1.05); DLBCL 1.31 (0.93-1.7). Egger p=0.02, small negative studies missing. Authors: 'provide evidence that risk of NHL is not increased in workers exposed to glyphosate.' Every estimate compatible with no effect, incl. the high-exposure stratum the scope names: contradicts. |
| Kabat GC, Price WJ, Tarone RE 2021 · Cancer causes & control : CCC | meta-analysis | mixed | moderate | OCCUPATIONAL exposure reanalysis of the 6 studies underlying a prior NHL meta-analysis, testing sensitivity to exposure-definition and latency assumptions. Summary RR ranged from a null 1.05 (95% CI 0.87-1.28) for ever-exposure with no lag |
| Rana I, Nguyen PK, Rigutto G, Louie A, Lee J, Smith MT, Zhang L 2023 · Chemosphere | mechanism | supports | moderate | Mechanism-tier systematic review (175 studies, >50,000 extracted data points) applying the 'key characteristics of carcinogens' framework to glyphosate/GBF in vivo, ex vivo, and in vitro data (human and animal). Found strong evidence for ge |
| Panzacchi S, Tibaldi E, De Angelis L, Falcioni L, Giovannini R, Gnudi F, Iuliani M, Manservigi M, Manservisi F, Manzoli I, Menghetti I, Montella R, Noferini R, Sgargi D, Strollo V, Truzzi F, Antoniou MN, Chen J, Dinelli G, Lorenzetti S, Mantovani A, Mesnage R, Perry MJ, Vornoli A, Landrigan PJ, Belpoggi F, Mandrioli D 2025 · Environmental health : a global access science source | animal | supports | moderate | EXPERIMENTAL ANIMAL dosing (Sprague-Dawley rats, Ramazzini Institute Global Glyphosate Study; prenatal-onset exposure through 104 weeks) at the EU ADI (0.5 mg/kg/day), 5 mg/kg/day, and EU NOAEL (50 mg/kg/day) — doses framed as regulatory 's |
| Chang VC, Koutros S, Hurwitz LM, Zhou W, Andreotti G, Parks CG, Sandler DP, Rothman N, Machiela MJ, Beane Freeman LE, Hofmann JN, Berndt SI 2025 · Environment international | observational | supports | moderate | OCCUPATIONAL exposure (1,868 male pesticide applicators, buccal DNA, Agricultural Health Study — the same prospective cohort central to the NHL meta-analyses). High lifetime glyphosate use was associated with mosaic loss of chromosome Y, a |
| Tindle AN, Hansford BM, Peterson H, Swafford B, Labadie J, Trepanier LA 2025 · Veterinary and comparative oncology | animal | supports | low | RESIDENTIAL/environmental exposure (pet dogs, Golden Retriever Lifetime Study, nested case-control); canine multicentric lymphoma is a classic comparative-oncology model invoked in the human NHL debate. DNA strand breaks were elevated at ly |
| Boffetta P, Ciocan C, Zunarelli C, Pira E 2021 · La Medicina del lavoro | meta-analysis | contradicts | moderate | OCCUPATIONAL exposure updated meta-analysis (6 non-overlapping studies, 1,878 exposed NHL cases; Leon 2019 pooled AGRICAN/CNAP/AHS cohorts 56.8% and Pahwa 2019 NAPP 30.1% of weight): ever-exposure meta-RR 1.05 (95% CI 0.90-1.24, I2=0%); case-control studies only 1.21 (0.95-1.53); highest exposure category 1.15 (0.72-1.83; 3 studies, same 3 studies' ever-exposure 1.13, 0.77-1.66). Subtypes: DLBCL 1.29 (1.02-1.63; 4 studies, not a-priori, authors say not significant after multiplicity), FL 0.84 (0.61-1.17), CLL/SLL 1.33 (0.65-2.70). Egger p=0.04 (publication bias). Authors: 'a lack of an association between exposure to glyphosate and risk of NHL overall'. Near-null ever-exposure and a highest-stratum estimate compatible with no effect: contradicts. COI: first author consults for glyphosate producers on unrelated matters. |
| Chang ET, Delzell E 2016 · Journal of environmental science and health. Part. B, Pesticides, food contaminants, and agricultural wastes | meta-analysis | mixed | low | OCCUPATIONAL exposure meta-analysis (6 studies for NHL): meta-RR=1.3 (95% CI 1.0-1.6), marginally significant with the CI lower bound sitting at the null; Hodgkin lymphoma and leukemia associations were null. Authors' own conclusion: eviden |
| Zhang L, Rana I, Shaffer RM, Taioli E, Sheppard L 2019 · Mutation research. Reviews in mutation research | meta-analysis | supports | moderate | OCCUPATIONAL exposure meta-analysis (5 case-control studies + the updated 2018 Agricultural Health Study cohort): meta-RR for highest cumulative GBH exposure = 1.41 (95% CI 1.13-1.75); using the earlier 2005 AHS update instead gave meta-RR= |
| MacLean J. 2026 · MetaArXiv | observational | supports | low | Non-peer-reviewed case-study/policy-analysis preprint (not epidemiological data) arguing Greim et al. 2015 — a Monsanto-ghostwritten article — misrepresented a rodent carcinogenicity study (Kumar 2001) and that regulators/courts subsequentl |
| Smith-Roe SL, DeVito MJ, Co C, Ramaiahgari SC, Easterling M, Rice JR, Dunlap PE, Crizer DM, Zhou Z, Merrick BA, Xie G, Harris SF, Shockley KR, Tandon A, Oktay A, Mav D, Shah R, Borrel A, Gombar V, Masten SA, Paules RS, Ferguson SS 2026 · Toxicological sciences : an official journal of the Society of Toxicology | in-vitro | mixed | moderate | In-vitro mechanistic study (human HaCaT keratinocyte and HepaRG hepatocyte lines, NIEHS Division of Translational Toxicology) designed explicitly to address the IARC-vs-EPA/EU discrepancy on genotoxicity. Pure glyphosate was 'weakly and inc |
| Meloni F, Satta G, Padoan M, Montagna A, Pilia I, Argiolas A, Piro S, Magnani C, Gambelunghe A, Muzi G, Ferri GM, Vimercati L, Zanotti R, Scarpa A, Zucca M, De Matteis S, Campagna M, Miligi L, Cocco P 2021 · Environmental health : a global access science source | observational | tested-null | moderate | OCCUPATIONAL case-control (Italy, ItGxE 2011-17; 867 lymphoma cases, 774 controls; only 36 subjects (2.2%) ever exposed, 15 with medium-high confidence). NHL category: ever-exposed OR 1.4 (95% CI 0.62-2.94; 14 exposed cases), medium-high confidence 1.2 (0.35-4.21), medium-high cumulative 1.5 (0.49-4.81), medium-high intensity 2.2 (0.90-5.31); authors 'did not find an association' with NHL and name low statistical power as a major limitation. Subtype: follicular lymphoma OR 3.7 (1.06-12.8; 4 exposed cases), 7.1 (1.57-31.9) at medium-high confidence. Every NHL point estimate leans toward the claim with an interval including 1 - underpowered trend, tested-null; nothing on the object points against, so not mixed. |
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