Information Note: Reconsideration of a Request for the Special Review of Glyphosate Herbicides Containing Polyethoxylated Tallowamine

December 2012

In response to a November 2011 Federal Court decision, Health Canada's Pest Management Regulatory Agency (PMRA) has now completed its reconsideration of a request for a special review of glyphosate containing the formulant polyethoxylated tallowamine (POEA). The PMRA has again found that a special review is not required. The original request was made by a member of the public in May 2009 and the original decision not to initiate this special review was made in August 2009. (The reasons for this decision can be found in Information Note: Request for a Special Review of Glyphosate Herbicides Containing Polyethoxylated Tallowamine.)

The Special Review Request and the Judicial Review of Health Canada's Decision

On 25 May 2009, a member of the public requested a special review of glyphosate pesticides containing POEA. This request involved the claim that these pesticides posed a range of unacceptable risks to human health and to the environment. After reviewing the information provided by the requester, the PMRA concluded that a special review was not warranted and on 24 August 2009 informed the requester of its decision.

On 25 September 2009, the requester filed a challenge in Federal Court of the PMRA's decision to deny the request for a special review of glyphosate. During the proceedings, however, the basis of this challenge was narrowed down from the PMRA's conclusions about a range of human health and environmental risks posed by glyphosate with POEA to its conclusions only about the risks to amphibians in small ephemeral wetlands.

On 21 November 2011 the  Federal Court released its decision in this matter. In ordering a reconsideration, the Court noted some apparent inconsistencies in the documentation on which the PMRA based its decision to refuse the special review request. Because of these inconsistencies in particular, the PMRA decided not to appeal the decision and thus reconsidered the request for a special review.

The Reconsideration of the Special Review Request

On 10 January 2012, the PMRA advised the requester of the special review that it was reconsidering the request. In accordance with the Federal Court's decision, this reconsideration was confined to an assessment of the risk to amphibians in ephemeral wetlands of the aerial spraying of glyphosate with POEA in a forestry context. The PMRA invited the requester to submit additional information, which the requester did.

The PMRA completed its reconsideration of the special review request (including the additional information submitted) on 23 July 2012. It found that the particular use of glyphosate products that was the subject of the request did not pose an unacceptable risk to the environment. As a consequence, the PMRA determined that a special review of glyphosate with POEA was not required.

The PMRA found that laboratory studies suggested that glyphosate products containing POEA are indeed more toxic to amphibians than glyphosate alone. Yet, when seen in the context of all the studies available, these results did not offer credible and compelling evidence that glyphosate products created a serious possibility of an unacceptable risk to the environment. In particular, recent scientific studies under progressively more realistic conditions showed no significant adverse effects on amphibians. In addition, the initial results of ongoing field studies of breeding success of amphibians in forest wetlands following operational application of glyphosate products showed no significant effects on breeding effort, reproductive success, or abundance and fitness of wood frogs in herbicide-treated areas.