# Convenience Boolean (yes/no) function to identify chemical membership and treatment within the httk project. Allows easy identification of whether or not a chemical CAS is included in various aspects of the httk research project (by model type and species of interest). While it is our intent to keep these lists up-to-date, the information here is only for convenience and should not be considered definitive. ```r is.httk(chem.cas, species = "Human", model = "3compartmentss") ``` ## Arguments - `chem.cas`: The Chemical Abstracts Service Resgistry Number (CAS-RN) corresponding to the chemical of interest. - `species`: Species desired (either "Rat", "Rabbit", "Dog", "Mouse", or default "Human"). - `model`: Model used in calculation, 'pbtk' for the multiple compartment model, '1compartment' for the one compartment model, '3compartment' for three compartment model, '3compartmentss' for the three compartment model without partition coefficients, or 'schmitt' for chemicals with logP and fraction unbound (used in predict_partitioning_schmitt). ## Returns - **logical**: A Boolean (1/0) value that is TRUE if the chemical is included in the httk project with a given modeling scheme (PBTK) and a given species ## Details Tox21: Toxicology in the 21st Century (Tox21) is a U.S. federal High Throughput Screening (HTS) collaboration among EPA, NIH, including National Center for Advancing Translational Sciences and the National Toxicology Program at the National Institute of Environmental Health Sciences, and the Food and Drug Administration. (Bucher et al., 2008) ToxCast: The Toxicity Forecaster (ToxCast) is a HTS screening project led by the U.S. EPA to perform additional testing of a subset of Tox21 chemicals. (Judson et al. 2010) ExpoCast: ExpoCast (Exposure Forecaster) is an U.S. EPA research project to generate tenetative exposure estimates (e.g., mg/kg BW/day) for thousands of chemicals that have little other information using models and informatics. (Wambaugh et al. 2014) NHANES: The U.S. Centers for Disease Control (CDC) National Health and Nutrition Examination Survery (NHANES) is an on-going survey to characterize the health and biometrics (e.g., weight, height) of the U.S. population. One set of measurments includes the quantification of xenobiotic chemicals in various samples (blood, serum, urine) of the thousands of surveyed individuals. (CDC, 2014) ## Examples ```r httk.table <- get_cheminfo(info=c("CAS","Compound")) httk.table[,"Rat"] <- "" httk.table[,"NHANES"] <- "" httk.table[,"Tox21"] <- "" httk.table[,"ToxCast"] <- "" httk.table[,"ExpoCast"] <- "" httk.table[,"PBTK"] <- "" # To make this example run quickly, this loop is only over the first five # chemicals. To build a table with all available chemicals use: # for (this.cas in httk.table$CAS) for (this.cas in httk.table$CAS[1:5]) { this.index <- httk.table$CAS==this.cas if (is.nhanes(this.cas)) httk.table[this.index,"NHANES"] <- "Y" if (is.tox21(this.cas)) httk.table[this.index,"Tox21"] <- "Y" if (is.toxcast(this.cas)) httk.table[this.index,"ToxCast"] <- "Y" if (is.expocast(this.cas)) httk.table[this.index,"ExpoCast"] <- "Y" if (is.httk(this.cas,model="PBTK")) httk.table[this.index,"PBTK"] <- "Y" if (is.httk(this.cas,species="rat")) httk.table[this.index,"Rat"] <- "Y" } ``` ## References Bucher, J. R. (2008). Guest Editorial: NTP: New Initiatives, New Alignment. Environ Health Perspect 116(1). Judson, R. S., Houck, K. A., Kavlock, R. J., Knudsen, T. B., Martin, M. T., Mortensen, H. M., Reif, D. M., Rotroff, D. M., Shah, I., Richard, A. M. and Dix, D. J. (2010). In Vitro Screening of Environmental Chemicals for Targeted Testing Prioritization: The ToxCast Project. Environmental Health Perspectives 118(4), 485-492. Wambaugh, J. F., Wang, A., Dionisio, K. L., Frame, A., Egeghy, P., Judson, R. and Setzer, R. W. (2014). High Throughput Heuristics for Prioritizing Human Exposure to Environmental Chemicals. Environmental Science & Technology, 10.1021/es503583j. CDC (2014). National Health and Nutrition Examination Survey. Available at: https://www.cdc.gov/nchs/nhanes.htm. ## See Also `in.list` for determining chemical membership in several other key lists ## Author(s) John Wambaugh

is.httk function