Treatment of trees with Monosodium Methanearsenate (MSMA) for Bark Beetle Control

Background

Public concerns have been expressed about the perceived health risks of exposure to trees treated with the arsenical pesticide Glowon® or Monosodium Methane Arsenate (MSMA) that was used for bark beetle management.  These treatments occurred from the mid-1980's to 2004 in various locations in the interior of the province.  Since 2005, the product's registration has expired and it is no longer used in British Columbia. 

This web page serves to inform the public about the known issues, documented concerns and actions taken to address them.  One of these issues was to provide the public with better information on the known locations of treated trees to reduce their potential exposure to these trees.  The Ministry of Forests and Range (MFR) will be providing maps showing the locations of these trees based on the best available information from licensee and district records.  This page also provides information on the current MFR policy and procedures for documenting known locations of MSMA treated ("legacy") trees and describing the recommended actions when treated trees are encountered.  The page also provides factual information on the known risks to human health and to the environment that these trees may pose. 

MSMA Policy

• Policy document
   

• Babine Timber Sales Unit MSMA Treated Tree Management Policy (pdf, 2.95 mb, posted May 29, 2008)

Links & Documentation

Forest Practices Board Complaint Investigation

• FPB Investigation summary

MSMA Toxicology and Environmental Impacts

• Morrissey, C. et al.  2008,  Pesticide Treatments affect Mountain Pine Beetle Abundance and Woodpecker Behaviour (Ecological Soc. of America, Vol 18(1) January 2008 |  PDF Version

• US Environmental Protection Agency - Re-registration Eligibility Decision Document for Arsenicals, August, 2006

  • Other information related to the EPA re-registration eligibility decision (contains the most current information)

Letter from WALP (now Ministry of Environment) regarding authorization for burning MSMA treated trees in beehive burners

• Sample Letter (pdf, 31 k, posted Feb. 11, 2008)

Maps and Brochures

MSMA Treated (Legacy) Tree Brochure

• Brochure (pdf, 1.6 MB, posted Feb. 11, 2008)

Maps Showing MSMA Treated Tree Locations

• Districts and licensees are currently compiling the information on known locations of MSMA treated trees.  Maps showing the general locations will be posted on this site when they become available.  The more detailed information (see example below) will be accessed through the MFR's silviculture records management system, RESULTS.  Public requests will likely require the assistance of MFR staff if the requester does not have permission to access RESULTS.

  • Sample of detailed RESULTS/Mapview output [Yellow polygons indicate location of MSMA treated trees] (pdf, 6 MB, posted June 27, 2008)

  • Example opening report from RESULTS (pdf, 153 k, posted June 27, 2008)

  • Progress of submitted data that has been input into RESULTS (pdf, 11k, posted July 9, 2008)

• Electronic Data Submission Guidelines