NEW YORK (AP) — A federally funded study has found a possible link between aluminum in some childhood vaccines and persistent asthma, but experts say the study has several shortcomings. The study spotlights a possible connection between aluminum and asthma, but it does not claim the ingredient causes the breathing condition. And its top author says there is no reason to change current vaccine recommendations. Officials say more study is needed to try to confirm the association. It was published Tuesday by the medical journal Academic Pediatrics.