The correct functions of your lungs contribute to the normal ph level of between 7.35 and 7.45 in your blood. if your lungs do not exchange and remove carbon dioxide from your blood, the blood ph will change. a reading of ph 6.4 of your blood indicates: a. no health risk, as part of normal ph changes in your body that in this case bring it closer to neutral ph. b. a health problem due to the concentration of hydrogen ions (h+) being 10x higher than normal in your body. c. a health problem due to the concentration of hydroxide ions (oh-) being 2x higher than normal. d. a health problem due to the concentration of hydrogen ions (h+) being 2x higher than normal in your body. e. a health problem due to the concentration of hydroxide ions (oh-) being 10x higher than normal in your body.