Ajax XML causing potential memory leak?

Question

I have a timer firing off every couple minutes to update a piece of info in the DOM. In Chrome developer tools I'm seeing memory increases after every call and by doing a Heap profile I found detached DOM tree. Did I miss something in my code?

function update() {
    var preferredName;
    var url = '/foo?bar=1';
    var xml = $.ajax({
        async: false,
        url: url,
        dataType: 'xml'
    });
    $(xml).find("item").each(function () {
        preferredName = $(this).find("value").text();
    });

    $('#name').text(preferredName);
}