de>extr_ctd</code> column names: <code>pub_med_ids</code> or <code>pub_med_i_ds</code> are now <code>pubmed_ids</code>.</li>
<li>Introduced <code>extr_pubchem_section_</code> internal function to fetch FEMA and GHS info, avoiding repeated code.</li>
<li>Introduced <code>check_na_warn</code> internal function to generate warnings for missing IDs.</li>
<li>Created <code>with_extr_sandbox</code> to handle cache for CRAN examples.</li>
</ul></div>
</div>
    <div class="section level2">
<h2 class="pkg-version" 