Pure nicotine
Pure nicotine, of 98 or 99% purity, should not be purchased or used under any circumstances, except by licensed laboratories with a fume cabinet and hazmat facilities. It is a highly dangerous poison in this form, and a small spillage on the skin is likely to be lethal.
Nicotine is used as an insecticide, and when used to fumigate a greenhouse for example it will kill anything living - including any humans unfortunate enough to be inside. 99% nicotine has a strength of 990mg, or 990mg/ml, and is almost ten times stronger than 100mg, normally the strongest eliquid base sold for mixing, which itself is dangerous enough.
It is as dangerous as pure potassium cyanide.
Note that pure nicotine is far more dangerous than high-strength e-liquid because it will be rapidly absorbed into the bloodstream if there is a spill on the skin. This is not normally the case with e-liquid because the nicotine seems to be bound or 'locked' by PG and/or VG, and there appears to be a time window in which the liquid may be rinsed off. This will not be the case with pure nicotine. Note also that simply opening a bottle of it can result in a room filling with toxic fumes - it should only be handled in a vapor cabinet.
No mention on ECF
Small amounts of nicotine may be used in the manufacture of e-liquid by those qualified to do so. No one else should either buy the raw materials or attempt to use them.
ECF will auto-censor out any names of or weblinks to dealers anywhere, of any type, that supply pure nicotine. No mention may be made by members or suppliers of such vendors, and attempts to evade the auto-censor will result in a ban on the member or supplier.
DO NOT MENTION ANY SUPPLIER OF PURE NICOTINE ON ECF.
This restriction does not apply in the Manufacturers and Wholesalers private forum, or in the Suppliers private forums.