Consultation document on chlorinated paraffins: chapter 1

Background

2.1 Substance Information

Chlorinated paraffins are chlorinated hydrocarbons (n-alkanes) that can have carbon chain lengths ranging from 10 to 38. They are grouped by chain length: short chain chlorinated paraffins (chlorinated paraffins with 10-13 carbon atoms), medium chain chlorinated paraffins (chlorinated paraffins with 14-17 carbon atoms) and long chain chlorinated paraffins (chlorinated paraffins with ≥18 carbon atoms).

2.2 Priority Substance List

Chlorinated paraffins were included on the first Priority Substances List (PSL) program under the 1988 Canadian Environmental Protection Act for assessment of potential risks to the environment and human health. In 1993, Environment Canada and Health Canada published an assessment report that concluded short chain chlorinated paraffins constitute or may constitute a danger to human health or life as set out in the Act. However, data at that time was considered insufficient to conclude whether short, medium or long chain chlorinated paraffins were harmful to the environment or whether medium or long chain chlorinated paraffins were considered a danger to human health.

Following the publication of the proposed assessment report, research to address data gaps relevant to the assessment of impacts of chlorinated paraffins on the environment was undertaken and an industry survey on the Canadian manufacture, import and uses of chlorinated paraffins was conducted for the years 2000 and 2001 through a Canada Gazette Notice issued pursuant to section 71 of the Canadian Environmental Protection Act, 1999 (CEPA 1999). Literature was also reviewed for new exposure and toxicological data on chlorinated paraffins on human and non-human organisms in Canada and elsewhere.

On June 11, 2005, the Ministers of the Environment and of Health published in the Canada Gazette, Part I, for a 60-day public comment period, the summary of the scientific results of the follow-up assessment on chlorinated paraffins and a statement indicating the proposed measures on the basis of scientific considerations. Comments were received from industry and industry associations on the follow-up assessment. Stakeholder input was carefully reviewed by Environment Canada and Health Canada. The final follow-up assessment report was revised based on these comments.

2.3 Final Follow-Up Assessment Report Conclusions for Chlorinated Paraffins

On August 30, 2008, a notice summarizing the scientific considerations of a final follow-up assessment report was published by Environment Canada and Health Canada in the Canada Gazette, Part I for chlorinated paraffins that have the molecular formula C_nH_xCl(2n+2−x) in which 10 ≤ n ≤ 38, under paragraph 68(b) of CEPA 1999. The final follow-up assessment report concluded that:

• All chlorinated paraffins meet the criteria under paragraph 64(c)¹ of CEPA 1999; and
• Chlorinated paraffins containing up to 20 carbon atoms meet the criteria under paragraph 64(a)² of CEPA 1999.

Based on conclusions of the assessment, it was therefore recommended that all chlorinated paraffins be added to Schedule 1 of CEPA 1999.

Furthermore, chlorinated paraffins containing up to 20 carbon atoms are predominantly anthropogenic, and the available data regarding their persistence and bioaccumulation potential indicate that they satisfy the criteria outlined in the Persistence and Bioaccumulation Regulations, made under CEPA 1999. Chlorinated paraffins containing up to 20 carbon atoms were recommended for addition to the Virtual Elimination List.

2.4 Proposed Risk Management Approach

A proposed Risk Management Approach for chlorinated paraffins was published by the Government of Canada on August 30, 2008. 

The proposed Risk Management Approach outlined that the risk management actions being considered for chlorinated paraffins included prohibition with potential exemptions. The prohibition regulation would prohibit the manufacture, use, import, sale and offer for sale of chlorinated paraffins, however specific use exemptions for some uses of chlorinated paraffins may be allowed where it can be demonstrated that there are no technically or economically feasible available alternatives.

2.5 Current Uses and Industrial Sectors

Total reported annual usage of chlorinated paraffins in Canada (production + imports − exports) was approximately 2.7 kilotonnes in 2000 and 2001. As production of chlorinated paraffins in Canada has stopped, chlorinated paraffins are now imported into Canada as chemical formulations from foreign producers or as formulations in products such as paints, sealants, plastics and metalworking fluids.

The vast majority of chlorinated paraffins consumed in Canada are medium chain chlorinated paraffins; while much smaller quantities of short chain chlorinated paraffins and long chain chlorinated paraffins are also being consumed in specific applications. In 2001, the two dominant end-use applications for chlorinated paraffins in Canada were in the formulation of metalworking fluids such as cutting oils and high pressure lubricating oils used in the metalworking industry and as a plasticizer in polyvinyl chloride (PVC) applications. Chlorinated paraffins are also used as flame retardants in various plastics and rubber or formulated chemical products (e.g., adhesives, paints, sealants).

Metalworking Fluids

Approximately 15 metalworking fluid formulators in Canada consumed an estimated 1.2 kilotonnes of chlorinated paraffins in 2001. No significant changes have been observed in the use of chlorinated paraffins in metalworking applications from the 2001 analysis. Chlorinated paraffins are used as extreme pressure additives across a wide temperature range to enhance lubrication and surface finish in demanding metalworking and forming applications where hydrodynamic lubrication cannot be maintained. Medium chain chlorinated paraffins are the dominant chlorinated paraffins used in the metalworking industry.

Polyvinyl Chloride

Approximately 15-25 companies in the polyvinyl chloride (PVC) processing sector in Canada consumed an estimated 1.2 kilotonnes of chlorinated paraffins in 2001. According to new information available, the use of chlorinated paraffins in the PVC sector has significantly dropped in the last few years.

Chlorinated paraffins are used in the PVC processing industry as secondary plasticizers, and in some cases as flame retardants. While there are several different sub-sectors within the PVC processing industry, the use of chlorinated paraffins (on a volume basis) has historically been restricted to three specific sub-sectors where they have been used as secondary plasticizers and flame retardants, namely: (i) flooring manufacturing; (ii) wire and cable sheathing and insulation; and (iii) wall coverings and emulsions. Medium chain chlorinated paraffins are the dominant chlorinated paraffins used in the PVC processing industry, with only minor amounts of short chain chlorinated paraffins or long chain chlorinated paraffins used.

Paints and Coatings, Adhesives and Sealants, and Rubber and Elastomers

Chlorinated paraffins are used in other end-use segments in Canada, in addition to metalworking fluids and PVC, although in much smaller quantities. These specific applications are: (i) paints and coatings; (ii) adhesives and sealants; and (iii) rubber and elastomers. Approximately 0.3 kilotonnes of chlorinated paraffins were used in the Canadian paints and coatings, adhesives and sealants, and rubber and elastomer sectors in 2001. No significant changes have been observed in the use of chlorinated paraffins in rubber, paints and coating or adhesives and sealants, from the 2001 analysis.

The majority of chlorinated paraffins consumed in these applications are medium chain chlorinated paraffins along with small amounts of long chain chlorinated paraffins. Chlorinated paraffins are used in these applications because of their ability to: (i) improve the flexibility (and therefore the durability) of the coating; and (ii) reduce the amount of time needed to achieve "tack-free" conditions.

2.6 International Initiatives

2.6.1 European Union

Short chain chlorinated paraffins are on the initial list of 16 substances identified as substances of very high concern under the European Union's Registration, Evaluation, Authorisation and restriction of Chemicals (REACH) program.

2.6.2 International Agreements

United Nations Economic Commission for Europe Convention on Long-Range Transboundary Air Pollution

In December 2006, the Parties to Protocol on Persistent Organic Pollutants, which include Canada, agreed that short chain chlorinated paraffins should be considered as a persistent organic pollutant as defined by the Protocol. Furthermore, discussions on the addition of short chain chlorinated paraffins have been ongoing and are expected to conclude in December 2009.

Stockholm Convention on Persistent Organic Pollutants

The Persistent Organic Pollutants Review Committee of the Stockholm Convention is currently considering the draft risk profile for short chain chlorinated paraffins.

1. Paragraph 64(c) of CEPA 1999 defines a substance as "toxic" if it is entering or may enter the environment in a quantity or concentration or under conditions that constitute or may constitute a danger in Canada to human life or health.

2. Paragraph 64(a) of CEPA 1999 defines a substance as "toxic" if it is entering or may enter the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment or its biological diversity.