Nicotine presence can be detected in the blood for a short period only (about 48 hours) . However, its metabolite, cotinine, can be detected up to about three weeks from the last use and the cut-off detection levels is 200 ng/ml.
Q: What is the purpose of toner? Our skin is happiest at a pH of 5.5. Toner balances the pH of your skin. If you are acne prone the skin is too acidic. So finding a slightly alkaline toner can help balance the acidic nature. If the skin is dry, it is too alkaline, so finding a toner that has a lower pH can bring it to a happy balance of 5.5. Toning 1 minute after cleansing allows all the beneficial molecules to absorb into the skin as it is still wet.
Hairstylists choose a toner that is on the opposite side of the color wheel from the unwanted tone. If your hair color is too red, a green toner is used; if your hair is too orange a blue toner is used; and if your hair color is too yellow, a purple toner will neutralize the unwanted yellow tone. Toner can last an average of 4 to 8 weeks, depending on how well you take care of your hair color investment. Some toners last longer. When toner fades away, lighter warmer color is often exposed. Toner can be reapplied at the salon when faded, if desired.