  We present sensitive sub-mm imaging of the Seyfert 1 galaxy NGC 7469 at 850
$\mu $m and 450 $\mu $m with the Submillimetre Common User Bolometer Array
(SCUBA) on the James Clerk Maxwell Telescope (JCMT) and ^{12}CO J=3-2 line
observations of its central starbursting region. The global dust spectrum, as
constrained by the new set of sub-mm data and available 1.30 mm and IRAS 100
$\mu $m, 60 $\mu $m data reveals a dominant warm dust component with a
temperature of $\rm T_{\rm d} \sim 35$ K and a global molecular gas-to-dust
ratio $\rm M(H_2)/M_{\rm d}\sim 600$. Such high values are typical for
IR-bright spirals and in order to reconcile them with the significantly lower
ratio of ~ 100 obtained for the Milky Way a cold dust reservoir, inconspicuous
at FIR wavelengths, is usually postulated. We present evidence that, rather
than unaccounted cold dust mass, this high ratio suggests an overestimate of
$\rm M(H_2)$ from its associated ^{12}CO J=1-0 line luminosity by a factor of ~
5 when a Milky Way value for this conversion is used in starburst nuclei
environments.
