This page has been archived on the Web

Information identified as archived is provided for reference, research or recordkeeping purposes. It is not subject to the Government of Canada Web Standards and has not been altered or updated since it was archived. Please contact us to request a format other than those available.

Responses to Stakeholders' Comments regarding Tributyltins on the Proposed Risk Management Approach for Non-Pesticidal Organotin Compounds and the Consultation Document for the Proposed Risk Management Measure for the Non-Pesticidal Uses of Tributyltin

The final follow-up ecological assessment report for non-pesticidal organotin compounds was published by Environment Canada in the Canada Gazette, Part I, on August 8, 2009, under section 68 of the Canadian Environmental Protection Act, 1999 (CEPA 1999). This assessment report concluded that tributyltins meet the criterion set out in paragraph 64(a) of CEPA 1999 and meet the criteria for persistence and bioaccumulation potential as set out in the Persistence and Bioaccumulation Regulations.

On August 8, 2009, a proposed Risk Management Approach for Non-Pesticidal Organotin Compounds was published on Environment Canada's website.  The Government of Canada indicated in this document that it would consider the addition of non-pesticidal uses of tributyltins to the Prohibition of Certain Toxic Substances Regulations, 2005.

On January 19, 2011, Environment Canada consulted with stakeholders on this regulatory proposal through a Consultation Document on the Proposed Risk Management Measure for the Non-Pesticidal Uses of Tributyltins, which Contain the Grouping (C4H9)3Sn sent to stakeholders and published on Environment Canada’s website for a 30-day comment period.

The current document outlines the various comments received from stakeholders on the 2009 Proposed Risk Management Approach for Non-Pesticidal Organotins as they pertain to tributyltins and on the Consultation Document on the Proposed Risk Management Measure for the Non-Pesticidal Uses of Tributyltins. The current document also outlines how the comments have been considered in the preparation of the proposed Prohibition of Certain Toxic Substances Regulations, 2012 published in Part 1 of the Canada Gazette on July 23, 2011.

Part I: Comments on the Proposed Risk Management Approach fro Non-Pesticidal Organotin Compounds – pertaining to tributyltins

Topic: Proposed Risk Management Action –Tributyltins

Comment:

We agree with the addition of tributyltins to the virtual elimination list and with the proposal to add tributyltins to the Prohibition of Certain Toxic Substances Regulations, as long as the permitted uses identified in the Risk Management Approach are specifically allowed.

Response:

Adding tributyltins to the proposed Prohibition of Certain Toxic Substances Regulations, 2012 would not prohibit permitted uses identified in the proposed Risk Management Approach.

Comment:

With respect to the list of permitted uses, the following activities should also be included for the sake of clarity:

  • Storage of tin stabilizers
  • Transportation of tin stabilizers
  • Disposal of tin stabilizers

Response:

It is understood that tributyltins may be incidentally present in tin stabilizers. The proposed Prohibition Regulations, 2012, would not apply to instances where tributyltins are incidentally present, therefore by extension, the storage, transportation and disposal of tin stabilizers as well as their manufacture, use, sale, offer for sale or import would not be prohibited.

Comment:

We support the decision to add tributytins to the Prohibition Regulations, but we have some concern that the permitted uses of products where tributyltins are present as contaminants would not be prohibited. Therefore, we would support the development of a regulation that provides a prescribed limit for the presence of tributyltins in products or food as contaminants.

Response:

Although the overall objective is to manage any potential releases of tributyltins to the environment, some activities (such as the use of mono- and dibutyltin in PVC processing, as glass coatings and as catalysts and the manufacture of mono- and dibutyltin stabilizers) are not proposed for prohibition. This is because releases of tributyltins associated with such activities are being addressed through other risk management measures, or have limited environmental impact. For the mono and dibutyltins (which may contain small amounts of tributyltins), the risk management instrument is the Environmental Performance Agreement which manages the release of tin stabilizers (mono- and dibutyltins) into the environment. For the risk management of tetrabutyltin, a Code of Practice is being developed to manage releases of tetrabutyltin to the aquatic environment.

It is noted that tetrabutyltin is used in the manufacturing of the mono- and dibutyltins. During this process, the tributyltins contained in the tetrabutyltin, along with the tetrabutyltin, are converted into the mono- and dibutyltins.

Comment:

Although we agree that there are no known formal risk management measures for non-pesticidal tributyltin applications in place in Canada at the moment, to the extent practicable, industry has traditionally endeavoured to manage the risk from tributyltin contaminants contained as impurities in other products.

Response:

This is noted by Environment Canada.

Comment:

We do not agree with the decision to rely on an Environmental Performance Agreement with the vinyl industry to reduce releases of organotins into the environment.

Response:

An Environmental Performance Agreement (EPA) Respecting the Use of Tin Stabilizers in the Vinyl Industryhas been in place since March 2008, to manage the release of tin stabilizers (mono- and dibutyltins) into the environment, including any tributyltins that may be present in the stabilizers. Verifications conducted to date on close to half of the facilities covered by the EPA reveal that measures are currently in place, or in a few cases are being developed, to prevent the potential releases of these substances at these facilities.

Part II: Comments on the regulatory proposal for adding tributyltins to the Proposed Prohibition of Certain Toxic Substances Regulations

Topic: Risk Management Action

Comment:

We are pleased to see that the tributyltins prohibition will not apply to instances where these substances are present in mono-, di- and tetrabutyltin, which will allow their import, sale and use/processing.

Response:

This is noted by Environment Canada.

Comment:

We support the proposed Prohibition Regulations of non-pesticidal uses of tributyltins, subject to the permitted uses identified. However, to avoid any misinterpretation, we request that the following be added to the list of permitted uses that will appear in Schedule 2 of that regulation:

“Tributyltins which are incidentally present in tin stabilizer manufacturing waste”.

Response:

Given that the proposed prohibition would not apply to instances where tributyltins are incidentally present, all the associated activities (i.e. manufacture, use, sale, offer for sale, import, including waste generated by these activities) would also not be prohibited. However, Environment Canada will examine how these waste streams, which may contain some residual tributyltins, are being managed to determine if other measures may be needed to address any potential releases of tributyltins from this source.

Date modified: