Independent Expert Review Panel (IERP) of the Human Health Risk Assessment (HHRA) for Flin Flon, Manitoba, and Creighton, Saskatchewa



Toxicology Excellence for Risk Assessment (TERA) convened an independent expert review panel (IERP) to review the human health risk assessment (HHRA) for Flin Flon, Manitoba, and Creighton, Saskatchewan (  The Hudson Bay Mining and Smelting Company (HBMS) operates a base metal smelting complex in Flin Flon.  An HHRA was conducted by Intrinsik Environmental Sciences Inc. for HBMS to address the potential human health risks associated with exposure to smelter-related metals in soils and other environmental media in the Flin Flon and Creighton area.  A Technical Advisory Committee with representatives from national and provincial agencies provided technical guidance.  HBMS provided funding for the study and the IERP review.


A panel of eight scientists with extensive experience in the key areas necessary to review the HHRA were selected by TERA.  The panel met in June 2009 to review and discuss the draft HHRA.  The panel addressed a number of questions and issues (the charge to the panel), discussed the strengths and weaknesses, assumptions, calculations, alternate interpretations, methodologies, and conclusions reached by the study, and reached conclusions and recommendations regarding the scientific support for the HHRA conclusions. TERA drafted a summary of the panel discussions and conclusions, which was reviewed by the panel and revised.  The IERP report summarized the discussions of the charge questions and the recommendations of the IERP.  This report is available at the link below.


The panel members generally agreed that overall the HHRA followed the commonly accepted human health risk assessment methods.  Overall, the panel agreed that the input data and assumptions used in the assessment were valid and appropriate, except for those identified during discussion.  The panel agreed that in general, the HHRA was presented clearly and completely, and that it was a very comprehensive effort.  Panel members recognized the challenges in conducting such a comprehensive assessment and thought that their suggestions and recommendations could be incorporated fairly readily.  The IERP found the HHRA followed commonly accepted human health risk assessment methods and the assumptions were valid and appropriate.


The panel chair and staff of TERA reviewed the revised HHRA and Intrinsik’s responses to the IERP recommendations.  It was  determined that the authors were responsive to the panel’s concerns and recommendations and had revised the risk assessment accordingly.  The overall conclusion of the HHRA was to recommend a comprehensive Exposure Study to collect additional information on actual exposure levels for Flin Flon area children to some chemicals.  The conclusion of the Flin Flon Soils Study is that the likelihood of adverse health effects among Flin Flon area residents from exposure to the metals evaluated are negligible to low.


Dr. Michael Dourson, chair of the IERP, traveled to Flin Flon in June 2010 to present the findings of the IERP to the community. He reported on the IERP conclusions and recommendations (see link below of poster presented at the Open House). While there were differences of scientific opinion on a few issues amongst the panelists and between the panel and Intrinsik, the results of the assessment and conclusions, and the protection of public health, were not impacted by these differences.  The HHRA and results were found to be scientifically-sound and appropriately health protective. 





For more information, contact Jacqueline Patterson ( or 513-521-7426)