Cotinine is detectable in blood for at least several days after exposure to tobacco smoke. Depending on how much you smoke, the level of cotinine in your blood will reflect a nonsmoker level in 7 to 10 days. The nicotine test that offers the longest detection window is a hair follicle nicotine test. These are rarely administered due to their expense, but they do exist.
High pH is NOT always BAD! But, high pH is NOT always GOOD, either! The recommendation that swimming pools should be operated at pH levels between 7.2 and 7.6 is almost universal. This recommendation is enshrined in generations of pool books and literature. It's embedded in many state swimming pool codes. Unfortunately, for most swimming pools, it's also far from ideal.
About low swimming pool chlorine level, stabilizer, and cyanuric acid... My pool is 27,000 gallons. The pH level is good and the swimming pool is very clean, but I cannot keep any chlorine in pool. The pool store told us to use stabilizer in pool, so we put it in sock and tied it to ladder as we were told to do.