Magnetic signature of industrial pollution of stream sediments and correlation with heavy metals: Case study from South France

Industrial pollution is one of the most important environmental threats, with serious consequences for the future. Thus, its detailed study is of great importance. Apart from expensive and time-consuming chemical methods, several rapid and cheap proxy methods have been developed recently, one of them being based on rock-magnetic parameters. In the present paper we examine the use of rock-magnetic methods designed to assess the degree of pollution of recent stream sediments taken from the Arc river (Provence, France). The aim was to identify industrially-derived magnetic particles and to link this 'magnetic pollution' to concentrations of heavy metals. Geological basements allow the easy determination of magnetic particles of industrial origin. Our results clearly demonstrate that magnetic anomalies, observed in the stream sediments along the river, can be explained by human activities, as they correlate well with concentrations of lead, zinc, iron and chromium.