Background quality of the coastal marine waters of the North West Shelf, Western Australia.

A sediment quality survey was undertaken at six locations in the marine waters off the Pilbara coast to determine concentrations of a range of selected metal and organic chemicals under natural background conditions. The suite of chemicals measured included arsenic, cadmium, chromium, cobalt, copper, lead, mercury, nickel, selenium, silver, vanadium, zinc, butyltin compounds, total petroleum hydrocarbons, BTEX chemicals, polycyclic aromatic hydrocarbons, organochlorine and organophosphate pesticides and PCBs. The work was undertaken to provide a baseline for evaluating anthropogenic changes or trends in sediment quality around regional centers of development (eg. Ports) and to ascertain the applicability the nationally recommended sediment quality guidelines from the Australian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZECC & ARMCANZ, 2000) to the region.