The treatment, known as therapeutic apheresis, passes a patient's blood through a machine, filters out targeted substances, and returns the blood to the body. It is generally used in severe cases where medication alone cannot sufficiently remove cholesterol – fat-carrying particles linked to cardiovascular disease risk. "This was unexpected, as PFAS and microplastics are chemically distinct from lipoproteins and were not the intended targets of the treatment." Microplastic levels fell in patients with high starting levels but rose in those with low levels. Still, the findings raise an intriguing possibility: A filter designed to capture harmful fat-carrying particles may also remove some PFAS and microplastics traveling alongside them.