  Recent detections of complex organic molecules in dark clouds have rekindled
interest in the astrochemical modeling of these environments. Because of its
relative closeness and rich molecular complexity, TMC-1 has been extensively
observed to study the chemical processes taking place in dark clouds. We use
local thermodynamical equilibrium radiative transfer modeling coupled with a
Bayesian statistical method which takes into account outliers to analyze the
data from the Nobeyama spectral survey of TMC-1 between 8 and 50 GHz. We
compute the abundance relative to molecular hydrogen of 57 molecules, including
19 isotopologues in TMC-1 along with their associated uncertainty. The new
results are in general agreement with previous abundance determination from
Ohishi & Kaifu and the values reported in the review from Agundez & Wakelam.
However, in some cases, large opacity and low signal to noise effects allow
only upper or lower limits to be derived, respectively.
