According to scientists, the garbage patch may contain 100 million tons of plastic It has been carried to this area by ocean currents and winds from all over the Pacific Scientists used to think that plastic bags or bottles broke up into small pieces only after many years in cold water. However, studies have shown that it happens much more quickly. In about a year, plastic bottles, bags, or other plastic objects are broken down into many small pieces, which may remain in the water for a hundred years.