The problems and possibilities of passive thermoacoustical tomography are d
iscussed. Algorithms for reconstruction of internal temperature in the huma
n body are proposed. These algorithms take into account heat transfer and b
lood circulation and the absorption factor, obtained previously. The result
s of reconstruction of deep temperature in the human hand in simulations wi
th the medium with a heated object are reported. These results support the
possibility of the correlation measurements of the thermal acoustic radiati
on. Such measurements allow the information on ultrasound absorption by the
object under study to be obtained and open the way to the development of a
passive acoustic tomography system using a priori information on the absor
ption factor.