Risk Assessment for Extended Phase-Out of Pentachlorophenol

OUR CHALLENGE

In 2022, Health Canada’s Pesticide Management Regulatory Agency (PMRA) proposed an accelerated phase-out of pentachlorophenol (PCP) for treating utility poles and wood products, aiming to eliminate PCP use and stockpiles within less than a year. The rapid timeline was intended to mitigate potential risks to workers and the public. Our client, while agreeing to phase out PCP use, sought an extended compliance schedule, more in line with the U.S.’s longer phase-out period, to ensure operational continuity while maintaining worker and public safety. 

OUR APPROACH

We conducted a comprehensive risk evaluation and prepared an expert affidavit to support the client’s request for an extended phase-out period. Key actions included: 

• Performing risk calculations to assess potential cancer risks for facility workers based on different compliance periods. 

• Evaluating measured air PCP concentrations in facilities to ensure compliance with worker safety regulations. 

• Analyzing worker and resident urine PCP levels (creatinine-normalized) to determine whether they exceeded acceptable regulatory limits. 

• Preparing a detailed affidavit for submission to Health Canada’s PMRA, demonstrating that extending the compliance period would not increase risks for workers or the general public. 

OUR IMPACT

Our risk assessment demonstrated that measured air PCP concentrations and urinary PCP levels in both workers and the public were well within acceptable regulatory limits under the current conditions. Our calculations also showed that extending the compliance period from less than 1 year to more than 3 years posed no additional risk. Based on our findings, in conjunction with a regulatory evaluation performed by counsel, Health Canada’s PMRA agreed to extend the compliance period to 3 years, allowing our client to phase out PCP use in a more manageable time frame without compromising safety.