TABLE 2.

pH values for human body fluids

FluidapH range
Amniotic fluid7.0-7.3
Aqueous humour7.2-7.4
Bile6.4-8.6
Cerebrospinal fluid7.3-7.4
Faeces5.0-8.0
Gastric juice2.0-4.0
Small intestine fluid5.0-7.0
Large intestine fluid6.5-7.5
Saliva6.8-7.5
Sperm7.2-7.6
Synovial fluid7.3-7.6
Tears7.4-8.2
Urine4.5-8.2
Blood7.1-7.4
Airway gland fluidb≈6.97
Cystic fibrosis sputum (sol)c5.9-7.0
  • a Information obtained from Lentner (24, 25) except as noted.

  • b Jayaraman et al. (15).

  • c Perricone et al. (35).