Skip to main content

A Class Approach to Hazard Assessment of Organohalogen Flame Retardants (2019) / Chapter Skim
Currently Skimming:

Appendix B: Methodologic Details of Analyses to Evaluate Feasibility of Class Approach and to Define Subclasses
Pages 52-62

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 52...
... chemicals were listed in nonpolymeric, additive organohalogen flame retardants all sources; this suggests substantial heterogeneity in the (OFRs) that considered function, chemical structure, chemical space identified by various groups.
Read the entire page →
From page 53...
... reports repeated on the expanded set of OFR analogues, includthat are registered and validated by the European Com- ing collection of data by running OPERA predictions7 and mission's Joint Research Center to be OECD-compliant.4 retrieval of data on these chemicals from the EPA Dash board.8 STEP 2. GENERATE AN "EXPANDED" SET OF CHEMICAL ANALOGUES ON THE BASIS OF STEP 3: EVALUATE THE COMBINED FUNCTIONAL, STRUCTURAL, AND CHEMINFORMATIC SIMILARITY PREDICTED BIOACTIVITY INFORMATION OF THE SEED SET TO THE ANALOGUES TO EVALUATE WHETHER THE OFRs ARE To identify the analogues that are structurally similar DISTINGUISHABLE AS A SINGLE CLASS to the OFR seed set, the committee developed an automated KNIME workflow to identify all organohalogens Comparing OFR Seed Set to Analogues: (about 200,000 structures)
Read the entire page →
From page 54...
... 54 Initial structures Remove inorganics and mixtures Clean salts and counterions Normalize tautomers Remove duplicates QSAR-ready structures Final inspection FIGURE B-1 Standardization of structures to provide QSAR-ready structures amenable to modeling: desalted, stereochemistry-stripped, tautomers and nitro groups standardized, valence corrected, structures neutralized when possible, and duplicates removed, among other steps. Figure available at www.nap.edu/25412.
Read the entire page →
From page 55...
... 2016) to identify the by biologic activity or as a component of an SAR model most enriched Toxprint Chemotypes in the OFR seed and as described in this section.
Read the entire page →
From page 56...
... Following the supervised GA learn The goal of supervised analyses was to determine ing techniques, the committee used results on the descripwhether a selected set of properties can differentiate the tors and conducted an additional supervised PCA analysis. OFR seed set from the analogues accurately.
Read the entire page →
From page 57...
... and analogues (shown as green dots)
Read the entire page →
From page 58...
... represent each group that can also be associated with a predicted biologic activity whenever possible. Using ex STEP 4: DEFINE SUBCLASSES FOR pert judgment, the committee grouped the OFR inventory HAZARD EVALUATION into eight structural classes on the basis of predicted bio logic activity (such as GABA receptors, aromatase activ The chemical space of the OFR inventory was pro- ity, and ER/AR modulators)
Read the entire page →
From page 59...
... of Chemicals 25495-98-1; 25637-99-4; 3194-55-6; 3194-57-8; 134237-50-6; 134237-51-7; 134237-52-8; 678970-17-7; Polyhalogenated alicycles 17 678970-16-6; 678970-15-5; 169102-57-2; 138257-19-9; 138257-18-8; 3322-93-8; 77-47-4; 87-84-3; 1837-91-8 Polyhalogenated aliphatic carboxylate 4 3066-70-4; 5445-17-0; 5445-19-2; 19660-16-3 52434-59-0; 1522-92-5; 3296-90-0; 3234-02-4; 96-13-9; Polyhalogenated aliphatic chains 12 109678-33-3; 85535-84-8; 71011-12-6; 85535-85-9; 63449-39-8; 75-95-6; 79-27-6 1084889-51-9; 893843-07-7; 1025956-65-3; Polyhalogenated benzene alicycles 4 155613-93-7 168434-45-5; 23488-38-2; 39569-21-6; 87-83-2; 85-22-3; 38521-51-6; 58495-09-3; 31780-26-4; Polyhalogenated benzene aliphatics and functionalized 19 84852-53-9; 497107-13-8; 59447-55-1; 34571-16-9*
Read the entire page →
From page 60...
... " with highlighting to show struc- 2016. Category approach for selected brominated flame tural features matched with the OFR categories.13 retardants: Preliminary structural grouping of brominated The organohalogen structures that are not covered by flame retardants.
Read the entire page →
From page 61...
... OPERA models for predicting physicochemical minated flame retardants (BFRs) in food.
Read the entire page →
From page 62...
... 2016. Flame Retardant Exposure Assessment Data- Worth, and J
Read the entire page →

Key Terms

  • ofr seed
  • flame retardants
  • chemical space
  • expanded set
  • ofr categories

  • efsa journal
  • organohalogen flame
  • toxprint chemotypes
  • class approach
  • brominated flame

  • biologic activity
  • danish epa
  • ofr chemicals
  • ofr inventory
  • seed chemicals

  • consumer product
  • product safety
  • predicted biologic
  • principal component
  • food safety

  • safety authority
  • scientific opinion
  • supervised analyses
  • component analysis
  • green dots

  • pca analysis
  • european food
  • ofr analogues
  • comparing ofr
  • chemical analogues


    • This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
    More information on Chapter Skim is available.