PT10 Toxicity of Complex Mixtures
Exhibit Hall
8:00 AM - Tuesday, 11 November 2003
(PT173) A conceptual framework for investigation of cause in pulp and paper environmental effects monitoring.
Hewitt, M.1, Dube, M.2, Culp, J.2, 3, MacLatchy, D.4, Munkittrick, K.4, 1 National Water Research Institute, Burlington, Ontario, Canada2 National Water Research Institute, Saskatoon, Saskatchewan, Canada3 University of New Brunswick, Fredericton, New Brunswick, Canada4 Univeristy of New Brunswick, Saint John, New Brunswick, Canada
ABSTRACT- Environmental Effects Monitoring (EEM) has completed two cycles in the pulp and paper sector and has established several national patterns of effects in fish and benthos of receiving waters. One of the next requirements for individual facilities to undertake is an investigation of the causes of the effects. We propose a framework here that utilizes a tiered approach. We have incorporated several ongoing research projects that are currently characterizing sources and identities of bioactive chemicals that originate from the pulp and paper process. A determination of cause ultimately ends with the confirmation of individual chemicals present in a effluent that elicit the responses observed in conducting EEM studies. It is our contention that this level of detail is not required at all sites where differences have been noted, nor is it economically feasible. We propose that the depth to which an investigation of cause is conducted be determined on a site-specific basis that is decided upon by stakeholders. Our framework consists of 3 tiers, each of which provides more information on the sources and identities of the responsible compounds. The first tier of our approach consists of confirmation that the source of the effect is indeed the discharger. The second tier involves investigating individual process effluents within the industrial facility to determine their relative contributions to the effects that have been observed. The final tier involves isolating and characterizing the individual chemicals associated with the responses using techniques such as bioassay-directed fractionation. This framework can be used in a stakeholder decision-making process to determine the extent of the investigation. Intensive research projects utilizing the approaches within this framework at selected sites will ultimately provide a database of causative processes and/or substances that will be useful in conducting investigations at other sites.
Key words: multiple stressors, cause and effect, complex mixtures, environmental effects monitoring