Environmental endocrine disruptors (EDCs) represent a major problem for human health.Some PEEs can accumulate in the fatty tissue of the human body thanks to their lipophilic nature, and are known as persistent organic pollutants (POPs). To assess the benefit of cholestyramine treatment on POPs blood levels in obese patients of childbearing age undergoing bariatric surgery, in order to reduce their preoperative POPs load more rapidly. Indeed, the investigators hypothesize that cholestyramine is capable, outside of acute exposure accidents, of promoting the elimination and release of POPs in the human population. Given this hypothesis, a treatment administered prior to bariatric surgery could reduce pre-operative plasma levels of POPs and thus, in fine, minimize the concentrations reached post-operatively, which are dependent on the release induced by lipolysis (massive and rapid weight loss) and pre-operative plasma concentrations.