The health effects of a Roundup-tolerant genetically modified maize (from 11% in the diet), cultivated with or without Roundup, and Roundup alone (from 0.1 ppb in water), were studied 2 years in rats. In females, all treated groups died 2–3 times more than controls, and more rapidly. This difference was visible in 3 male groups fed GMOs. All results were hormone and sex dependent, and the pathological profiles were comparable. Females developed large mammary tumors almost always more often than and before controls, the pituitary was the second most disabled organ; the sex hormonal balance was modified by GMO and Roundup treatments. In treated males, liver congestions and necrosis were 2.5–5.5 times higher. This pathology was confirmed by optic and transmission electron microscopy. Marked and severe kidney nephropathies were also generally 1.3–2.3 greater. Males presented 4 times more large palpable tumors than controls which occurred up to 600 days earlier. Biochemistry data confirmed very significant kidney chronic deficiencies; for all treatments and both sexes, 76% of the altered parameters were kidney related. These results can be explained by the non linear endocrine-disrupting effects of Roundup, but also by the overexpression of the transgene in the GMO and its metabolic consequences.
► A Roundup-tolerant maize and Roundup provoked chronic hormone and sex dependent pathologies. ► Female mortality was 2–3 times increased mostly due to large mammary tumors and disabled pituitary. ► Males had liver congestions, necrosis, severe kidney nephropathies and large palpable tumors. ► This may be due to an endocrine disruption linked to Roundup and a new metabolism due to the transgene. ► GMOs and formulated pesticides must be evaluated by long term studies to measure toxic effects.
Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize