A Decade of Research on the Environmental Impacts of Pulp and Paper Mill Effluents in Canada (1992-2002)

In the late 1980's, pulp and paper production worldwide became an area of increased environmental scrutiny by the public as dioxins and furans in effluents and paper products were found. At the same time, results from Swedish studies in the early 1980s provided some of the first evidence that effluents from some pulp mills were capable of inducing toxic responses in fish at very low concentrations in the receiving environment. In response to these studies, a number of Canadian studies were initiated to determine whether similar responses were seen in fish downstream of pulp mills in Canada . Reproductive alterations were identified at a number of locations, however not all studies demonstrated similar reproductive effects in the receiving environment. A new regulatory package for the pulp and paper industry was then introduced which set new levels for BOD, TSS and acute lethality as well as limits for dioxins and furans. In order to meet the new regulatory limits, a number of process and treatment changes were required by the industry however it was not known whether these upgrades would also improve the reproductive responses demonstrated in fish at a number of locations.

Subsequent to the regulatory package, the Minister of the Environment announced a large collaborative research program involving government, industry and academia. The original objectives of the research program were to 1) identify the causative organochlorine compounds, 2) determine how to eliminate them from the process, and 3) determine the short-term and long-term environmental effects of these compounds. Results from this research program along with feedback from the Canadian Environmental Effects Monitoring program (within the new regulations) would then be used to define what additional control actions may be necessary. The following is a review of the research conducted over the last 10 years following the implementation of the 1992 regulatory package. It is separated into three specific sections of research, 1) Field Studies and Mechanistic Research, 2) Development and Application of Bioassays, and 3) Characterization of Bioactive Chemicals.