According to a study published in Nature Communications, the mass of so-called invisible microplastics found in the upper waters of the Atlantic is around 12-21 million tonnes. Scientist Katsiaryna Pabortsava says it was previously hard to balance the amount of plastic found in the ocean against what was thought to have been put into it since the 1950s. This was down to earlier studies not measuring the concentrations of ‘invisible’ microplastic particles beneath the ocean surface. This study indicates there is a lot more plastic in the Atlantic than previously thought, which can severely damage marine ecosystems. Microplastics are defined as pieces smaller than 5mm.