$\mu$m colour (Section \[subsec:dust\_content\]). The emissivity index adopted is also indicated ($\beta =1$ or 2).\
$^\mathrm{c}$ Dust mass estimated in Section \[subsec:dust\_content\]. The emissivity index adopted is also indicated ($\beta =1$ or 2).\
$^\mathrm{d}$ H<span style="font-variant:small-caps;">i</span> gas mass estimated from H<span style="font-variant:small-caps;">i</span> 21 cm line observations. For the latter seven BCDs, the data are compiled in [@hirashita08]. The data for Mrk 487 and SBS 1319+579 are obtained from @hopkins02 and @huchtmeier07, respectively.\
$^\mathrm{e}$ Oxygen abundance compiled in @hopkins02 and @hirashita02 (and the references therein). When the error estimate is not available, we put a typical uncertainty in the measurement (0.04) [@shi05]. ]{}

As an indicator of dust abundance, we take dust-to-gas ratio. For the gas mass, we adopt H<span style="font-variant:small-caps;">i</span> gas mass $M_\mathrm{H\, I}$ estimated from H<span style="font-variant:small-caps;">i</span> 21 cm emission observations. The data of $M_\mathrm{H\, I}$ are already compiled by H08 for the common sample (i.e. the latter seven BCDs in Table \[tab:mdust\]). Among the newly added sample, there is no available H<span style="font-variant:small-caps;">i</span> data for UM 420 and Mrk 59, while the data for Mrk 487 and SBS 1319+579 are obtained from @hopkins02 and @huchtmeier07, respectively (for the latter, we used the formula in @lisenfeld98 to convert the 