Diagnosis of river pollution by PIXE

Abstract PIXE has been applied to analyse suspended particulates in urban river water. Samples were collected from the Tama River, which flows into Tokyo Bay, at nine locations in the lower reaches up to 25 km from its river mouth. The major element, Si, and minor elements, Al, P, S, Cl, K, Ca. Ti, Cr, Mn, Fe and Cu, were detected. The minor elements could be divided into four groups originated from natural ((1) seawater and (2) minerals) and human ((3) industrial and (4) livings) activities. The contents of elements from minerals were high upper stream and at turbulent areas, while those resulting from human activities increased from the middle areas. The results of ICP and AAS were consistent with the PIXE data.