From the food safety assessment rules that gave you the tiger, snakes, strychnine, and cassava laced with cyanide: It's natural therefore it's safe.

The very natural but poisonous strchynine tree. Illustration from Köhler's Medizinal-Pflanzen

Greg Paynter, of the Organic Federation of Australia, said the role of GM grasses in the food chain was "a sleeping giant".
"We’ll have humans consuming milk from cows that have been consuming genetically modified material. We just don’t know what effects we might have to deal with in the future.

"They’re talking about scientific testing but the natural processes and ecosystems have been tested over 3 billion years."

Read more:
In Genetically modified grass for dairy cows sparks concern
Date
June 20, 2014 The Age, Fairfax Press, Clare Kermond


The Pundit's thoughts:
Much better food safety rules: Scientific evidence about safety and history of safe human use as a food. Farming itself, and certainly ploughing, is not natural, but organic farmers do it.


Update. Natural Chinese herbal medicine. Natural aristolochic acid plant chemical. But causes cancer:

Tumour induction in rats following exposure to short-term high dose aristolochic acid I

The purpose of this study was to assess the carcinogenic activity of aristolochic acid I (AAI) in short-term high doses. Forty-four female Sprague--Dawley rats were randomly assigned to two groups. A dose of 50 mg/kg/day AAI was administrated to rats in the experimental group by gavage consecutively for 3 days, while the control group received only distilled water, after which renal function and pathological changes were assessed. At day 8 posttreatment AAI had induced elevations of both plasma urea and creatinine, coupled with increased urine production, urinary proteins, glucose and N-acetyl-b-glucosaminidase.
At 1, 3 and 6 months post-treatment renal function and urinary parameters for the experimental group approached baseline values. However, tumours and preneoplastic proliferation were both observed at 6 months for the experimental group. The rate of occurrence of preneoplastic proliferation in the kidneys was 100% (14/14); the rate of occurrence of renal tumours was 28.6% (4/14), which included three mesenchymal tumours and one case of renal oncocytoma; the rate of occurrence of extrarenal tumours was 7.1% (1/14), which was a case of mammary duct carcinoma. Renal preneoplastic proliferation and renal tumours, as well as extrarenal tumours, were not observed in control rats during the 6 months. These results differ from previous reports in that tumours originating from both epithelial and mesenchymal tissues were found, which may be attributed to the duration of treatment and the dosage of the drug. These data indicate that AAI administered in an acute manner at high doses does in fact have carcinogenic properties.

Mutagenesis vol. 20 no. 1 pp. 45--49, 2005 doi:10.1093/mutage/gei007

Min Cui, Zhi-Hong Liu , Qi Qiu, Heng Li and Lei-Shi Li

Research Institute of Nephrology, Jinling Hospital, Nanjing University

School of Medicine, Nanjing 210002, China