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Chemicals Management Plan Challenge Advisory Panel Summary Report
February 19, 2010 Meeting
Panel members present: Dr. Ted Boadway (Chair), Dr. Jack Bend, Dr. Conrad Brunk, Dr. Nicola Cherry, Dr. Scott Findlay, Dr. Steve Maguire, Dr. Gina Muckle, Dr. Peter Orris.
Regrets: Dr. John Eyles, Mr. Geoff Granville, Ms. Linda Lusby, Dr. Dayna Scott.
Outline:
The Challenge Advisory Panel meeting agenda for February 19, 2010, was structured around an overview of Batch 9 draft screening assessment reports. Government officials presented and answered questions related to the Batch 9 assessments.
Meeting Summary:
The meeting began with a scheduled in camera session for Panel members. Government officials were invited to attend following the in camera session.
Welcome and Introductory Comments:
The Chair welcomed all members and government staff. The meeting was opened with introductory remarks from the Chair. The Chair indicated that he would not provide a report from the Panel's in camera session but that Panel members would bring forward questions raised during the in camera session over the course of the day's discussions.
Panel Discussion on Batch 9 Draft Screening Assessment Reports:
Government staff presented an overview of draft screening assessments for the substances in Batch 9 of the Challenge.
Topics raised by Panel members included the following:
- Panel members asked about use of the term "substance X" in Challenge screening assessments, and particularly in the ecological assessment for the Batch 9 substance TGOPE (CAS # 7328-97-4). Government officials clarified this term was used in the report for
TGOPE because the information pertaining to the chemical analogue that had been provided to the government was subject to confidential business information (CBI) restrictions. In this case, information pertaining to the analogue "substance X" had been submitted as part of a New Substances Notification submission consistent with requirements under the New Substances Notification Regulations of the Canadian Environmental Protection Act, 1999 (CEPA 1999). - Panel members noted that a substance that is carcinogenic to humans could also be carcinogenic in other organisms (e.g. fish), and therefore asked for information regarding risk characterization for carcinogenicity endpoints in ecological assessments. After some discussion, the Panel agreed to defer further discussion of this topic to their next meeting, when staff with expertise could participate.
- For the substance methyl eugenol (CAS # 93-15-2), Panel members inquired as to the relevance of this being a naturally occurring substance. Government officials noted that the Panel has previously agreed that the source of a substance does not impact the risk assessment phase, but rather is relevant to the subsequent risk management phase.
- For the substances vanadium oxide (CAS # 1314-62-1) and antimony oxide (CAS # 1309-64-4), the issue of speciation of the substances was discussed. For metal compounds, methodologies used to measure levels in the environment generally do not distinguish between chemical species. Thus, while a particular toxicological effect may be specific to the metal species under assessment, exposure data will typically be derived for total metal levels (with metal oxides representing only a portion of total levels). This leads to very conservative estimate of total exposures and could impact planning and evaluation of risk management actions. Panel members emphasized that speciation studies should ideally be conducted for metal compounds.
For certain chemical substances, Panel members suggested clarifying language in the draft assessments, as detailed below. Government officials indicated they would take these suggestions into consideration when finalizing the draft assessments.
- For the substance PEDA (CAS # 41556-26-7), Panel members suggested adding additional detail to the draft screening assessment report regarding skin sensitization and neurological effects observed in animal studies.
- For Solvent Red 49 (CAS # 509-34-2), it was suggested that its use at very low concentrations as a colourant in some pet collars registered as pest control products in Canada should be elaborated upon in the draft screening assessment report.
- For the substance methyl eugenol (CAS # 93-15-2), Panel members suggested adding text to the draft screening assessment report to clarify exposure scenarios for different subpopulations, particularly infants.
- For vanadium oxide (CAS # 1314-62-1), it was suggested that additional detail regarding pulmonary effects and the potential for sensitization in highly exposed individuals should be added to the draft screening assessment report.
Overall, the Panel considered that weight of evidence and precaution were applied appropriately in the draft screening assessment reports.
Further Discussion:
Following the discussions of Batch 9 chemicals, government officials presented an overview of the assessment for one non-Challenge chemical. Panel members had previously indicated they would be amenable to providing advice on the occasional non-Challenge substance. A summary of this discussion will be published at a future date, aligning with timelines for release of the assessment report.
Topics for Discussion at Future Panel Meetings:
Three topics were identified by the Panel for possible future discussions:
- A discussion of weight of evidence and uncertainty.
- Occupational exposures to chemicals.
- A discussion of carcinogenicity endpoints in ecological assessments under the Challenge.
