An accurate test for how long does nicotine stay in your system can be performed via blood test. If a laboratory is testing for nicotine, it should be performed within 3 days of smoking. It is better for a laboratory to test for cotinine as it remains in the blood stream for about 10 days after smoking.
The pH in the human digestive tract varies greatly (see Human Digestive Tract pH Range Chart on the left side). The pH of saliva is usually between 6.5 - 7.5. After we chew and swallow food it then enters the fundic or upper portion of the stomach which has a pH between 4.0 - 6.5.he pH of any solution is the measure of its hydrogen-ion concentration. The higher the pH reading, the more alkaline and oxygen rich the fluid is. The lower the pH reading, the more acidic and oxygen deprived the fluid is. The pH range is from 0 to 14, with 7.0 being neutral.
Human blood has a pH of between 7.3 to 7.5, which is slightly on the basic side of the scale. If blood pH drops below 7.0 or goes higher than 7.8 the body can no longer function and dies. There are many other everyday implications to pH values. 1  Acidic soils must often be treated with lime, which is an alkaline substance,to neutralize the pH before planting. The pH will determine what type of plant will grow and thrive in the soil. In a marine environment, including an indoor aquarium, a basic pH of 8.1 to 8.4 makes it easier for fish to maintain their own cleanliness and resist illness. It has a slight antiseptic effect. pH describes the balance between hydrogen ions and hydroxide ions.