Human tear pH. Diurnal variations
L. G. Carney and R. M. Hill
Using a closed chamber microelectrode system, the tear pH levels of sixteen
subjects were monitored throughout the waking extent of five days. In
addition to the absolute mean pH differences found among subjects, diurnal
patterns of pH change could be identified for the majority. The amplitudes
and periods of these cycloid patterns, however, were distinctive to each
individual. Also, tear pH levels following periods of prolonged eye closure
were found to be notably more acid than those associated with the waking
hours.