Improving fate and ecotoxicity assessment tools to advance the ecological risk assessment of difficult to test multi-component substances

Transcription

1 Improving fate and ecotoxicity assessment tools to advance the ecological risk assessment of difficult to test multi-component substances Dan Salvito (RIFM); Miriam Leon-Paumen (ExxonMobil); Karen Jenner (Givaudan)

2 Project Development Output of the RIFM/ECETOC Workshop on difficult to test multiconstituent substances (November 2016) Formed a Community of Practice between academia, regulatory community and industry Projects are emerging LRi proposal on fate directed ecotoxicity testing Supporting OECD Technical Guidance on Difficult To Test Substances (TG 23) Paper summarizing workshop and research needs in draft

3 Briefly some background from the workshop Report on the RIFM/ECETOC Workshop: Developing a strategy to improve the environmental risk assessment of difficult to test multi-component substances Joop de Knecht, Daniel Salvito, Romanas Cesnaitis,Karen Eisenreich, Michelle Embry, Marc Fernandez Miriam León-Paumen, Karen Jenner, and Ed Salinas The views of the authors of this presentation are those of the authors and do not represent the views of their respective organizations

4 Affiliations Joop de Knecht Daniel Salvito Romanas Cesnaitis Karen Eisenreich Michelle Embry Marc Fernandez Miriam León-Paumen Karen Jenner Ed Salinas RIVM, Bilthoven, NL RIFM, Woodcliff Lake, NJ, USA ECHA, Helsinki FI USEPA, Washington, DC, USA HESI, Washington, DC, USA Environment and Climate Change Canada, Vancouver, BC, CD ExxonMobil, Mechelen, BE Givaudan, Ashford, UK BASF, Ludwigscahfen, DE

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6 Workshop Attendance By Region By Affiliation 8% 42% 13% 50% Europe 19% Industry 26% NA APAC Academia 42% Regulatory Authorities Other

7 What is a UVCBs/MCSs?

8 Common characteristics of UVCBs Contain numerous chemicals and cannot be represented by a simple chemical structure or defined by a specific molecular formula. Many are of natural origin (e.g., crude oil, coal, plant extracts, reaction products), contain unknown constituents, and cannot be completely separated into their constituent chemical species. The concept of impurities typically does not apply to complex substances. These are often produced according to a performance specification related to their physical-chemical properties.

9 UVCBs in REACH database Based on the information reported in IUCLID ~ 25% of registrations are for UVCB substances UVCB substance origin in IUCLID 1% 40% 16% 39% 3% 1% Empty Inorganic Organic Organometallic Other Petroleum product 9

10 Phase Three of the CMP Approximately 1550 substances remaining to be addressed in third phase of CMP ( ) Organics 330* Petroleum 640* ~190 organic UVCBs Inorganics Polymer 370* Also contain UVCBs 220* Slide Courtesy: ECCC Range of UVCB complexity from predictable alkyl chain variations (e.g., surfactants) to non predictable multiconstituent biologicals (e.g., fragrance oils) 10

11 Objectives of the Workshop Stated Goals: This Workshop was designed to identify best practices and key research needs to support environmental risk assessment. Breakout sessions were focused on priority areas leading to best practice recommendations Other goals: Enable communication between global regulatory authorities and industry sectors Begin the process of building a community of practice of expertise for this challenging area of testing and compliance

12 Types of information needed for UVCB RA Ideally, a combination of block and component-specific information and testing results of the mixture as a whole Decision criterion for testing might include degree of variability To cover high variability a probabilistic approach could be used Look at typical and worst case Tiered approach to the testing strategy What are you obliged to test for substances produced in limited tonnage / limited release

13 Considerations for selecting the appropriate approach By testing the UVCB as a whole or as fractions, tools are needed to determine when constituents are considered to be similar; the degree to which variability is acceptable By testing fractions or representative constituents the interactions may need to be considered How can the combined effects of constituents be assessed without being over-conservative Develop a matrix of fate/toxicity for substance components Ideally the approach selected is applicable for hazard and risk assessment purposes.

14 Difficulties with testing UVCBs Study of the whole substance does not provide information on the individual constituents. The composition of the total dissolved constituents might be different from the composition of the substance added. To maintain stable concentrations in water can be challenging, depletion of specific constituents can occur Since the environmental fate of the constituents could be different, the composition in the environment might not be the same as the composition of the registered substance that has been tested.

15 Methodology development - Examples Often UVCBs contain highly hydrophobic organic substances which associated with scientific, conceptual, and technical challenges - How can techniques like passive dosing overcome these challenges? Is it feasible / necessary to determine BCF values of each constituents - Determining low concentrations in fish lipids could be challenging How can we utilize the in vitro methodology to determine what to test in vivo - Can we test mixture in vitro test for different endpoints?

16 Priority Research Areas New Tools for structure identity/description Including Property Assessment (P-Chem Parameters) Development of blocks (related to fate versus toxicity) Tools for analysis and fractionation Approaches and techniques to measure toxicity and fate of complex UVCBs, e.g. passive dosing, WAF 2.0, utility of WWTP simulation Approaches to deal with the large variability within each UVCB Development of case studies, e.g. - Approach for hydrocarbons and other classes - Approaches for baseline toxicity versus more specific MoA

17 Why a HESI Project Committee? In addition to maintaining a Community of Practice The proposal has been given support by OECD, RIVM, ECHA, and ECCC UVCBs and MCSs represent a unique set of challenges The Workshop was meant to develop best practices across endpoints This effort needs to be completed Multiple methodologies were recommended for research and development Very few projects are underway and require the combined effort, up front, of industry, academia and regulatory authorities Models and methods for material characterization and hazard assessment need to be expanded beyond the few tools currently available that can manage multiple substances Tools and methods developed here will help address mixture ecotoxicology

18 Community of Practice Tiered Approach to UVCB Assessment Models and Methods Cataloging Case Studies Identifying model and method gaps Collaborative Research Projects Best Practices/Guidance Substance Characterization Endpoint Specific Case Studies New Test Methodologies Development of New Science

19 THANK YOU