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Exactly the same line of dissimulation and deceit used by Big Tobacco in refuting a CAUSAL link from smoking or chewing to lung (and many other) cancers...
Something like... "there has never been direct cause scientifically established between the use of tobacco, tobacco products or formulations and the occurence of cancers of any kind"
Truth-ish, as far as it went, but at base, a lie.
The debater/afficianado-of-argument will have a name for this kind of mendacious obfuscation.
That term, as an established feature and evil of The Tobacco Industry -by extension to Exxon/CEI et al- should be gotten out and repeated and repeated and repeated.