Major Study Clears Roundup as Cancer Threat

Large U.S. farm study finds no cancer link to Monsanto weedkiller

A large long-term study on the use of the big-selling weedkiller glyphosate by agricultural workers in the United States has found no firm link between exposure to the pesticide and cancer, scientists said on Thursday.

Published in the Journal of the National Cancer Institute (JNCI), the study found there was no association between glyphosate, the main ingredient in Monsanto's popular herbicide RoundUp, "and any solid tumors or lymphoid malignancies overall, including non-Hogkin Lymphoma (NHL) and its subtypes".

It said there was "some evidence of increased risk of acute myeloid leukemia (AML) among the highest exposed group", but added this association was "not statistically significant".

The article doesn't mention the strength of the "evidence of increased risk of acute myeloid leukemia." p = .06 or p = 0.45? It matters. If the former, it might be worth an even larger study to see if the effect is real. If they were to examine the correlation with enough possible cancers with roundup exposure there would be a mix of positive and negative, but non-significant relationships, merely by chance. In fact there a non zero chance of finding a significant positive correlation even when the underlying truth is zero relationship. The idea of statistics is to minimize that possibility, which can never be fully eliminated.

The findings are likely to impact legal proceedings in the United States against Monsanto, in which more than 180 plaintiffs are claiming exposure to RoundUp gave them cancer - allegations that Monsanto denies.

The findings may also influence a crucial decision due by the end of the year on whether glyphosate should be re-licensed for sale across the European Union.

EU countries had been due to vote on the issue on Thursday, but again failed to agree to a proposal for a five-year extension.

The EU decision has been delayed for more than a year after the World Health Organization's International Agency for Research on Cancer (IARC) reviewed glyphosate in 2015 and concluded it was "probably carcinogenic" to humans. Other bodies, such as the European Food Safety Authority, have concluded glyphosate is safe to use.

Roundup (and Monsanto) have been on the enviroweenies hit list for years. I'm sure this won't alter their efforts to ban it and take us back to 19th century farming. But now they'll have to find another excuse.