Presentations and recommendations from the workshop on the role of geochemical data in environmental and human health risk assessment, Halifax, 2010
Authors: Rencz A N , Kettles I M 
Published: February 2011

It is recognized that knowledge of geochemistry is an important component of environmental and human health risk assessments. Although much geochemical information needed to better inform risk assessments exits already, these data are not well represented in
many of these assessments. As a step towards improving practice in this area, Health Canada and Environment Canada sponsored a workshop on the role of geochemical data in ecological and human health risk assessments. The Workshop was presented by scientists from the Geological Survey of Canada
with recognized expertise in bedrock and surficial sediment geochemistry. The Workshop was by invitation and included federal and provincial representatives and members of the environmental consulting community.
The Workshop covered the following topics:
Use of geochemical data in risk assessments - a consultant's view
Causes of variation in geochemical data - natural spatial (horizontal and vertical) and analytical controls
Field sampling and analytical protocols
Estimating background geochemical composition
Case studies involving geochemical data
Discussion of priorities for improving practice and identifying gaps in existing data.

One aim of the Workshop was to develop a strategy for improving the guidelines for risk assessments by promoting more rigorous use of geochemical information. More specifically, the focus was on the application of existing geochemical data and on the needs for new types of data and developing tools
for their application. Information and ideas from the presentations and discussions are gathered here
in a final document. The document includes the Workshop proceedings and also contains lists of recommendations for making updates to existing guidelines, where appropriate.
For the purposes of this Workshop, geochemical information was restricted to the chemical elements associated with inorganic substances. The focus was on As, Cd, Cu, Ni, Pb, and Zn, in particular. Issues related to organic substances were not considered. There were presentations on a series of
topics relevant to risk assessment, followed by discussions and recommendations for improving practice. The discussions were guided to ensure that Workshop participants were familiar with the concern and also the guideline. Case studies were used to reinforce the concepts. There was also a
session dedicated to identifying knowledge gaps and making plans for moving forward.
The Workshop was held in the Radisson Hotel in Halifax, Nova Scotia, on March 17th and 18th, 2010. Additional introductory information on the Workshop is provided in the file entitled "Start Here_Executive Summary" and also in the 01_INTRODUCTION directory. This Open File provides a record of the
presentations and other documents associated with the Workshop.
The contents of Geological Survey of Canada Open File 6645 are organized into 10 directories, representing introductory materials (e.g. agenda and abstracts) and the 9 sessions and areas of subject matter covered at the Workshop. The directories related to the 9 sessions contain pdf files of the
presentations. There is a complete listing and more explanation of the directories in the file entitled
"Start Here_Executive Summary".