JSFiddle - React, Tailwind, and code Playground

HTML

<span>Select depatament</span><span>
    <select id="department" onchange="EnableSlaveSelectBox(this)" data-slaveelaments='{"a": 1, "b": "2"}'>
        <option selected disabled>-Select-</option>
        <option>1</option>
    </select>
</span>

JavaScript

function EnableSlaveSelectBox(element) {
    var d = $('#department').data('slaveelaments');
    
    console.log(d.a);
    console.log(d.b);
}