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Models, Applications, and Databases for Safer Chemicals Research


  • Exposure Analysis Modeling System
    Facilitates the development of aquatic ecosystem models for the rapid evaluation of the fate, transport, and exposure concentrations of synthetic organic chemicals, such as pesticides, industrial materials, and leachates from disposal sites.
  • Markov Chain Nest Productivity Model
  • Estimates the impact of pesticide exposures on the reproduction success of bird populations.
  • Markov Chain Nest Productivity Model Estimating Tool
    Estimates probabilities of failure in the presence of competing risks.
  • Stochastic Human Exposure and Dose Simulation (SHEDS) Models
    The SHEDS models are probabilistic models that can simulate cumulative (multiple chemicals) or aggregate (single chemical) exposures over time for a population via residential and dietary routes of exposure for a variety of multimedia, multipathway environmental chemicals.
  • Web-ICE
    Web-ICE is an internet application that models acute toxicity of untested aquatic species and terrestrial wildlife using measured data from a surrogate species

Web Applications

  • Adverse Outcome Pathway Wiki Exit
    System to develop and evaluate Adverse Outcome Pathways in a user-friendly format. An Adverse Outcome Pathway (AOP) is an analytical construct that describes a sequential chain of causally linked events at different levels of biological organization that lead to an adverse health or ecotoxicological effect. The AOP Wiki is coordinate by the European Commission Joint Research Center and the United States Environmental Protection Agency for the purpose of the Organization for Economic Co-operating and Development (OECD) programme on the development of AOPs.
  • Endocrine Disruption Screening Program for the 21st Century (EDSP21) Dashboard
    EPA researchers developed the EDSP21 Dashboard to provide access to new chemical data on over 1,800 chemicals of interest, in order to help the Endocrine Disruptor Screening Program evaluate chemicals for endocrine-related activity.
  • Gauging Reaction Effectiveness for the ENvironmental Sustainability of Chemistries with a Multi-Objective Process Evaluator (GREENSCOPE)
    GREENSCOPE is a sustainability assessment tool used to evaluate and assist in the design of chemical processes. Increasingly, the chemical industry is incorporating sustainability approaches in process design. The goal is to minimize resource use, prevent or reduce releases, and increase the economic feasibility of a chemical process. New chemical process or modifications to existing process are often proposed. These processes need to be assessed to determine whether they become more or less sustainable. EPA developed GREENSCOPE to help fill this need.
  • Indoor Semi-Volatile Organic Compound (i-SVOC)
    i-SVOC Version 1.0 is a general-purpose software application for dynamic modeling of the emission, transport, sorption, and distribution of semi-volatile organic compounds (SVOCs) in indoor environments. i-SVOC supports a variety of uses, including exposure assessment and the evaluation of mitigation options. SVOCs are a diverse group of organic chemicals that can be found in:
    • Pesticides;
    • Ingredients in cleaning agents and personal care products;
    • Additives to vinyl flooring, furniture, clothing, cookware, food packaging, and electronics.
    Many are also present in indoor air, where they tend to bind to interior surfaces and particulate matter (dust).
  • CompTox Chemicals Dashboard
    Provides access to chemical information and data for about 875,000 chemicals.
  • Probabilistic Reverse dOsimetry Estimating Exposure Distribution (PROcEED)
    PROcEED estimates unmeasured exposure concentration distributions from a population's measured biomarker concentrations.
    Research question: What is the potential distribution of exposure concentrations likely to have produced the biomarker concentrations measured in a population?
  • Tool for Reduction and Assessment of Chemicals and Other Environmental Impacts (TRACI)
    Assist in impact assessment for Sustainability Metrics, Life Cycle Assessment, Industrial Ecology, Process Design, and Pollution Prevention.
  • Toxicity Estimation Software Tool (TEST)
    TEST is a freely available tool that estimates toxicity and physical property values of a chemical using quantitative structure activity relationship (QSAR) models. The models in TEST are built using toxicity/physical property data sets that require a molecular structure and toxicity/property values from other compounds for its library database. TEST estimates values for a variety of toxicity and physical property endpoints and also provides detailed information allowing the user to assess the reliability of predictions.
  • Waste Reduction (WAR) Algorithm: Chemical Process Simulation for Waste Reduction
    The WAste Reduction (WAR) algorithm was developed so that environmental impacts of designs could easily be evaluated. The goal of WAR is to reduce environmental and related human health impacts at the design stage.



  • Program for Assisting the Replacement of Industrial Solvents (PARIS III)
    PARIS III is a freely available solvent substitution software tool designed to enable the effective replacement of harmful solvents with more benign single solvent or solvent mixtures. The physical and chemical properties of each listed solvent along with  representative data for PARIS’ environmental impact categories are in the library database. This software can generate a list of solvent(s) that may be effective replacements to the harmful solvent(s) under investigation. This tool along with experimental validation provides an effective approach for solvent substitution.
  • Probabilistic Reverse dOsimetry Estimating Exposure Distribution (PROcEED)
    PROcEED estimates unmeasured exposure concentration distributions from a population's measured biomarker concentrations
  • Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS)
    SeqAPASS is a fast, online screening tool that allows researchers and regulators to extrapolate toxicity information across species. For some species, such as humans, mice, rats, and zebrafish, the EPA has a large amount of data regarding their toxicological susceptibility to various chemicals. However, the toxicity data for numerous other plants and animals is very limited. SeqAPASS extrapolates from these data rich model organisms to thousands of other non-target species to evaluate their specific potential chemical susceptibility.   
  • Simulation Tool Kit for Indoor Air Quality and Inhalation Exposure (IAQX)
    IAQX version 1.1 is an indoor air quality (IAQ) simulation software package that complements and supplements existing indoor air quality simulation (IAQ) programs. IAQX is for advanced users who have experience with exposure estimation, pollution control, risk assessment, and risk management. There are many sources of indoor air pollution, such as building materials, furnishings, and chemical cleaners. Since most people spend a large portion of their time indoors, it is important to be able to estimate exposure to these pollutants. IAQX helps users analyze the impact of pollutant sources and sinks, ventilation, and air cleaners. It performs conventional IAQ simulations to calculate the pollutant concentration and/or personal exposure as a function of time. It can also estimate adequate ventilation rates based on user-provided air quality criteria. This is a unique feature useful for product stewardship and risk management.
  • Ubertool: Ecological Risk Web Application for Pesticide Modeling
    Ubertool provides environmental models used to evaluate ecosystem-level pesticide risks. The dashboard infrastructure integrates the processing of model results for over a dozen commonly-used EPA aquatic and terrestrial regulatory models and supporting datasets.
    Research question: What are the risks of pesticides to the health of ecosystems?