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Bpa) Analogues PROTOCOL FOR SYSTEMATIC REVIEW OF BISPHENOL A (BPA) ANALOGUES August 2015 Office of Health Assessment and Translation Division of the National Toxicology Program National Institute of Environmental Health Sciences Protocol for Systematic Review of Bisphenol A Analogues TABLE OF CONTENTS Table of Contents ............................................................................................................................... ii Background and Significance .............................................................................................................. 1 Background ........................................................................................................................................... 1 Rationale for Review ............................................................................................................................. 1 Significance ........................................................................................................................................... 1 Overall Objective and Specific Aims .................................................................................................... 3 Objective ............................................................................................................................................... 3 Specific Aims ......................................................................................................................................... 3 Key Questions and Analytical Framework ............................................................................................ 4 Methods ............................................................................................................................................ 5 Step 1. Problem Formulation ................................................................................................................ 5 Selection of BPA analogues for systematic review and similarity profiling ................................. 5 Step 2: Search For and Select Studies for Inclusion .............................................................................. 7 Literature search strategy ............................................................................................................ 7 Screening Process ......................................................................................................................... 9 Step 3: Extract Data from Studies ....................................................................................................... 11 Data Extraction Process and Data Warehousing ........................................................................ 11 Step 4: Quality Assessment of Individual Studies ............................................................................... 15 Internal Validity (“Risk of bias”).................................................................................................. 15 Risk-of-Bias Assessment Process ................................................................................................ 17 Missing Information for Risk of Bias Assessment ....................................................................... 18 Step 5. Evidence Integration and Similarity Profiling ......................................................................... 18 Structural Similarity Within HTS Data ......................................................................................... 19 Biological Similarity Within HTS Data ......................................................................................... 19 State-of-the-science report format ................................................................................................... 19 Introduction ........................................................................................................................................ 19 Methodology....................................................................................................................................... 20 Results ................................................................................................................................................. 20 Discussion ........................................................................................................................................... 20 References ....................................................................................................................................... 21 About the Protocol........................................................................................................................... 25 Contributors ........................................................................................................................................ 25 Evaluation team .......................................................................................................................... 25 Contract support ........................................................................................................................ 25 Protocol Peer-Reviewers ............................................................................................................ 25 Sources of support .............................................................................................................................. 26 Protocol History and Revisions ........................................................................................................... 26 Software .......................................................................................................................................... 26 ii Protocol for Systematic Review of Bisphenol A Analogues Appendices ...................................................................................................................................... 28 Appendix 1. Problem Formulation ...................................................................................................... 28 Appendix 2. Literature Search Strategy .............................................................................................. 31 Appendix 3. Risk-of-Bias Criteria ......................................................................................................... 73 Observational Studies (Human or Wildlife Studies) ................................................................... 73 Case Control Studies ................................................................................................................... 79 Experimental Animal Studies ...................................................................................................... 84 iii Protocol for Systematic Review of Bisphenol A Analogues BACKGROUND AND SIGNIFICANCE Background Bisphenol A (BPA) is a high production volume chemical used in the manufacture of polycarbonate plastics, epoxy resins, as a dye developer in thermal paper, and as a polymerization inhibitor in the formation of some polyvinyl chloride plastics (NTP 2008, FAO/WHO 2011, EFSA 2013). Polycarbonates are in consumer products such as plastic dinnerware, microwave ovenware, eyeglass lenses, toys, pacifiers, impact-resistant safety equipment, compact discs and automobile parts. Epoxy resins are used in protective linings of canned food and beverage containers, drinking water storage tanks, wine vat linings, some paints, floorings, and some dental composites (NTP 2008, FAO/WHO 2011, EFSA 2013). The types of thermal paper products where BPA might be used as a developer include cash register receipts and certain medical technical paper (Östberg and Noaksson 2010, EFSA 2013). Consequently, human exposure is widespread. BPA has been detected in the urine of 92% of Americans surveyed in the 2003-2004 National Health and Nutrition Examination Survey (NHANES) (Calafat et al. 2008). BPA has been reported to cause a wide range of adverse health outcomes in experimental animal studies; some similar findings in humans have also been linked to BPA exposure in observational epidemiology studies (vom Saal et al. 2007, National Toxicology Program (NTP) 2008, FAO/WHO 2011, Rochester 2013). Recent studies report widespread exposure to a variety of chemicals with structural or functional similarity to BPA, often referred to as BPA analogues or derivatives (and hencefore referred to generically as BPA analogues) (Table 1). BPA analogues have been detected in foodstuff (Cacho et al. 2012, Liao and Kannan 2013), house dust (Liao et al. 2012b), river and lake sediment (Liao et al. 2012e), personal care products (Liao and Kannan 2014), and thermal paper (Liao et al. 2012d, Becerra and Odermatt 2013). Several chlorinated and brominated derivatives of BPA are used as flame-retardants (Voordeckers et al. 2002, NTP 2008, FAO/WHO 2011, EFSA 2013). Importantly, BPA analogues have also been detected in human biological specimens (e.g. blood and urine) (Cobellis et al. 2009, Cobellis et al. 2010, Cunha and Fernandes 2010, Liao et al. 2012a, Zhou et al. 2013, Zhou et al. 2014). Other chemicals have also been identified as theoretical alternatives to BPA in thermal paper, although the extent to which they are actually being used is not known (U.S EPA 2014). Rationale for Review In contrast to BPA, most BPA analogues are poorly understood with respect to potential toxicity (NTP 2013, US EPA 2014). Use of these compounds may increase, however, as companies move towards using alternatives to BPA in consumer products (FDA 2012, FDA 2013, FIOH 2014). Two BPA analogues, BPS and BPF have been recently reviewed
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