THE SOURCE, COMPOSITION AND FLUX OF POLYCYCLIC AROMATIC-HYDROCARBONS IN SEDIMENTS OF THE RIVER DERWENT, DERBYSHIRE, UK

Freshwater surface sediments from 11 sites on the river Derwent (Derbyshire, UK) were sampled monthly during the period of June 1987 to May 1988. Samples were extracted and separated and the Polycyclic Aromatic Hydrocarbon (PAH) extract was analyzed using High Performance Liquid chromatography with a fluorescence detector. Identity of the peaks was confirmed by co-injection and Gas Chromatograph - Mass Spectrometry (GC-MS). Changes in total levels of nine parent PAH compounds were compared with rainfall data obtained for the study area. The time lag between PAH incorporation into sediments and preceding storm events varied between a minimum of 4 and a maximum of 30 days. All sites were found to be affected by diffuse PAH pollution. At certain sites and at times of heavy rainfall this contamination is overlayed by a greater input of PAH to the sediment from point sources. Road runoff was identified as a major diffuse source underlying atmospheric and point sources at particular sites. Small industrial areas had a greater influence on sediment PAH levels than the larger commercial or residential areas. Pyrene and fluoranthene were the dominant parent compounds and this is explained in terms of their availability and relative solubility. © 1990 Kluwer Academic Publishers.