Can swab tests tell if you have ever smoked tobacco?

Recently smoked: One of the most common ways to test for tobacco use is from using a swab to collect saliva. The test is for cotinine, a chemical by-product of nicotine which is in all tobacco. Cotinine last for about 4 days or longer, so if you had tobacco in the last week the test could be positive. There are more detailed tests that could detect tobacco in the past few months. There's no test for 'ever smoked'.