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Draft Screening Assessment Is Based Are Summarized Below Final Screening Assessment Petroleum Sector Stream Approach Low Boiling Point Naphthas [Industry-Restricted] Chemical Abstracts Service Registry Numbers 64741-42-0 64741-69-1 64741-78-2 Environment Canada Health Canada July 2013 Final Screening Assessment Industry-Restricted Low Boiling Point Naphthas Synopsis The Ministers of the Environment and of Health have conducted a screening assessment of the following industry-restricted low boiling point naphthas (LBPNs): CAS RNa DSLb name 64741-42-0 Naphtha (petroleum), full-range straight-run 64741-69-1 Naphtha (petroleum), light hydrocracked 64741-78-2 Naphtha (petroleum), heavy hydrocracked a The Chemical Abstracts Service Registry Number (CAS RN) is the property of the American Chemical Society, and any use or redistribution, except as required in supporting regulatory requirements and/or for reports to the government when the information and the reports are required by law or administrative policy, is not permitted without the prior written permission of the American Chemical Society. b DSL, Domestic Substances List. These substances were identified as high priorities for action during the categorization of substances on the Domestic Substances List (DSL) as they were determined to present greatest potential or intermediate potential for exposure of individuals in Canada, and were considered to present a high hazard to human health. These substances met the ecological categorization criteria for persistence or bioaccumulation potential and inherent toxicity to aquatic organisms. These substances were included in the Petroleum Sector Stream Approach (PSSA) because they are related to the petroleum sector and are considered to be of Unknown or Variable composition, Complex reaction products or Biological materials (UVCBs). These LBPNs are complex combinations of petroleum hydrocarbons that serve as blending constituents in final gasoline products, as intermediate products of distillation or as residues derived from distillation or extraction units. The final fuel products usually consist of a combination of LBPNs, as well as high-quality hydrocarbons that have been produced from refinery or upgrader facilities. In order to predict the overall behaviour of these complex substances for the purposes of assessing the potential for ecological effects, representative structures have been selected from each chemical class in the substances. The LBPNs considered in this screening assessment (CAS RNs 64741-42-0, 64741-69-1 and 64741-78-2) have been identified as industry restricted (i.e., they are a subset of LBPNs that may leave a petroleum sector facility and be transported to other industrial facilities). According to information submitted under section 71 of the Canadian Environmental Protection Act, 1999 (CEPA 1999) and other sources of information, these LBPNs are transported from petroleum sector facilities to other industrial facilities by ship and truck. Based on results of comparison of levels expected to cause harm to organisms with estimated exposure levels, releases to soil from loading, unloading and transport may cause harm to terrestrial organisms. However, given the conditions of such releases and the overall low frequency of spills to land, the risk of harm to the environment from these spills is low. As well, there is a low risk of harm to terrestrial organisms from releases of Final Screening Assessment Industry-Restricted Low Boiling Point Naphthas LBPNs to air from ship and truck loading. As there were no recorded spills to marine waters during transport, these LBPNs have a low risk of harm to aquatic organisms. Based on the information presented in this screening assessment on the frequency and magnitude of spills, there is low risk of harm to organisms or the broader integrity of the environment from these substances. It is concluded that the three industry-restricted LBPNs (CAS RNs 64741-42-0, 64741-69-1 and 64741-78-2) do not meet the criteria under paragraph 64(a) or 64(b) of the Canadian Environmental Protection Act, 1999 (CEPA 1999) as they are not entering 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 or that constitute or may constitute a danger to the environment on which life depends. A critical effect for the initial categorization of industry-restricted LBPNs was carcinogenicity, based primarily on classifications by international agencies. Additionally, benzene, a component of LBPNs, has been identified by Health Canada and several international regulatory agencies as a carcinogen. In addition to LBPN-specific data, benzene was selected as a high-hazard component of LBPNs to characterize potential exposure and risk to the general population from evaporative emissions of LBPNs. Several studies also confirmed skin tumour development in mice following repeated dermal application of LBPNs. LBPNs demonstrated limited evidence of genotoxicity in in vivo and in vitro assays, as well as limited potential to adversely affect reproduction and development. Information on additional LBPNs in the PSSA that are similar from a processing and a physical-chemical perspective was considered for characterization of human health effects. The physical-chemical properties of LBPNs indicate that these substances contain highly volatile components. Potential exposure to the industry-restricted LBPNs for individuals in proximity to shipping and trucking corridors results primarily from inhalation of vapours in ambient air due to evaporative emissions during transportation. The margins between the upper-bounding estimates of exposure to maximum air concentrations of total volatile organic compounds (VOCs) or benzene, based on the aromatic fraction of the LBPNs, and the critical inhalation effect levels are considered to be conservative and adequately protective to account for uncertainties related to health effects and exposure. General population exposure to industry-restricted LBPNs via the dermal and oral routes is not expected; therefore, risk to human health from the industry-restricted LBPNs via these routes is not expected. Based on information presented in this screening assessment, it is concluded that the industry-restricted LBPNs (CAS RNs 64741-42-0, 64741-69-1 and 64741-78-2) do not meet the criteria under paragraph 64(c) of the Canadian Environmental Protection Act, 1999 (CEPA 1999) as they are not entering the environment in a quantity or concentration or under conditions that constitute or may constitute a danger in Canada to human life or health. 3 Final Screening Assessment Industry-Restricted Low Boiling Point Naphthas It is therefore concluded that the three industry-restricted LBPNs listed under CAS RNs 64741-42-0, 64741-69-1 and 64741-78-2 do not meet any of the criteria set out in section 64 of CEPA 1999. 4 Final Screening Assessment Industry-Restricted Low Boiling Point Naphthas Introduction The Canadian Environmental Protection Act, 1999 (CEPA 1999) (Canada 1999) requires the Minister of the Environment and the Minister of Health to conduct screening assessments of substances that have met the categorization criteria set out in the Act to determine whether these substances present or may present a risk to the environment or to human health. Based on the information obtained through the categorization process, the Ministers identified a number of substances as high priorities for action. These include substances that • met all of the ecological categorization criteria, including persistence (P), bioaccumulation potential (B) and inherent toxicity to aquatic organisms (iT), and were believed to be in commerce in Canada; and/or • met the categorization criteria for greatest potential for exposure (GPE) or intermediate potential for exposure (IPE) and had been identified as posing a high hazard to human health based on classifications by other national or international agencies for carcinogenicity, genotoxicity, developmental toxicity or reproductive toxicity. A key element of the Government of Canada’s Chemicals Management Plan is the Petroleum Sector Stream Approach (PSSA), which involves the assessment of approximately 160 petroleum substances that are considered high priorities for action. These substances are primarily related to the petroleum sector and are considered to be of Unknown or Variable composition, Complex reaction products or Biological materials (UVCBs). Screening assessments focus on information critical to determining whether a substance meets the criteria set out in section 64 of CEPA 1999. Screening assessments examine scientific information and develop conclusions by incorporating a weight-of-evidence approach and precaution.1 Grouping of Petroleum Substances The high priority petroleum substances fall into nine groups of substances (Table A1.1 in Appendix 1) based on similarities in production, toxicity and physical-chemical 1 A determination of whether one or more of the criteria of section 64 are met is based upon an assessment of potential risks to the environment and/or to human health associated with exposures in the general environment. For humans, this includes, but is not limited to, exposures from ambient and indoor air, drinking water, foodstuffs and the use of consumer products. A conclusion under CEPA 1999 on the petroleum substances in the Chemicals Management Plan is not relevant to, nor does it preclude, an assessment against the hazard criteria specified in the Controlled Products
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