Tobacco contains nicotine
These side effects are annoying though, and while they arent life-threatening, it can be a nuisance

(c) For purposes of heading 9822.01.10, vessels (together with equipment, parts or materials), regardless of origin, that are exported temporarily from the United States and that undergo repairs or alterations in a country that is a party to a free trade agreement referred to in this subdivision, shall be accorded duty-free entry to the extent provided for in-- (i) article 2.6 of the United States-Singapore Free Trade Agreement, (ii) article 3.9 of the United States-Chile Free Trade Agreement, (iii) article 2.6 of the United States-Australia Free Trade Agreement, (iv) article 3.6 of the Dominican Republic-Central America-United States Free Trade Agreement, (v) article 2.6 of the United States-Morocco Free Trade Agreement, (vi) article 2.6 of the United States-Bahrain Free Trade Agreement, (vii) article 2.6 of the United States-Oman Free Trade Agreement, (viii) article 2.6 of the United States-Peru Trade Promotion Agreement, (ix) article 2.6 of the United States-Korea Free Trade Agreement, (x) article 2.6 of the United States-Colombia Trade Promotion Agreement, (xi) article 3.6 of the United States-Panama Trade Promotion Agreement, or (xii) article 2.8 of the United States-Mexico-Canada Agreement, under the terms of the pertinent Agreement article and on such basis as may be prescribed in regulations issued by the Secretary of the Treasury

Lyttons approach is designed to address both the physical addiction to nicotine and the emotional triggers that contribute to smoking