Pulp Mill-Sourced Substances in Sediments from a Coastal Wetland

Matata Lagoon, at the mouth of the Tarawera River is an ecologically important coastal wetland, situated some 26 km upstream of two paper mills which discharge their waste waters into the river. A matter of environmental concern is the extent to which pulp mill related organic substances, especially resin and fatty acids, have penetrated the upper and lower reaches of the lagoon. Investigation by GC-FID and GC-MS established that: (1) the lower lagoon sediments possessed resin acid levels similar to that presently within the river bed; (2) upper lagoon sediments were close to natural background levels; and (3) mass spectral ion ratio analyses confirmed that lower lagoon sediments were significantly contaminated by mill-sourced resin acids, whereas upper lagoon sediments were not significantly contaminated.