This dataset provides concentration-response data and associated general chemistry conditions for 26 experiments consisting of 149 tests regarding the acute toxicity of major ions to Ceriodaphnia dubia in a variety of test waters; it also provides LC50 estimates and the estimated ion mixtures at the LC50 for each toxicity test. This dataset is associated with the following publication: Mount , D., R. Erickson , T. Highland , R. Hockett , D. Hoff , T. Norberg-King , K. Peterson, Z. Polaske, and S. Wisniewski. The acute toxicity of major ion salts to Ceriodaphnia dubia: I. Influence of background water chemistry. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 35(12): 3039-3057, (2016).

This dataset provides concentration-response data and associated general chemistry conditions for 26 experiments consisting of 149 tests regarding the acute toxicity of major ions to Ceriodaphnia dubia in a variety of test waters; it also provides LC50 estimates and the estimated ion mixtures at the LC50 for each toxicity test. This dataset is associated with the following publication: Mount , D., R. Erickson , T. Highland , R. Hockett , D. Hoff , T. Norberg-King , K. Peterson, Z. Polaske, and S. Wisniewski. The acute toxicity of major ion salts to Ceriodaphnia dubia: I. Influence of background water chemistry. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 35(12): 3039-3057, (2016).

This effort involved intensive chronic toxicity testing of major ion salts (comprised of Na, K, Ca, Mg, Cl, SO4, HCO3/CO3) with the cladoceran, Ceriodaphnia dubia, a species known to be relatively sensitive to ion enrichment. This is the fourth in a series of manuscripts discussing the sensitivity of this species to major ions, with a specific focus of determining whether the principles governing acute response of this species to major ions also predict chronic responses. Results show this to be true, with acute-chronic ratios that are fairly consistent across different major ions, and responses to binary mixtures that show the same types of joint toxicity profiles as was observed previously for acute toxicity of major ions to this species. Mathematical models describing the response of these organisms were developed to predict the toxicity of major ion mixtures based on either chemical activity or chemical concentrations of ions in the mixture. These models showed good agreement with independent literature data on the chronic toxicity of major ion salts or ion mixtures to C. dubia. The datasets associated with this effort provide effect concentrations (EC20 and EC50) for 60 chronic toxicity tests conducted as part of this research, along with literature data extracted for comparison with model predictions. Data generated in this effort will inform efforts by OW, Regions, States, and Tribes to develop water quality standards/criteria for specific major ions (e.g., Cl, SO4). Perhaps more importantly, it provides part of the necessary scientific underpinning for developing standards/criteria that are sensitive to the specific composition of different sources of ion enrichment (e.g., produced water, mine drainage, irrigation return, industrial/municipal effluents) and can therefore support development of robust, integrated assessment tools. This dataset is associated with the following publication: Mount, D., R. Erickson, B. Forsman, T. Highland, R. Hockett, D. Hoff, C. Jenson, and T. Norberg-King. Chronic toxicity of major ion salts and their mixtures to Ceriodaphnia dubia. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 38(4): 769-783, (2019).

This effort involved intensive chronic toxicity testing of major ion salts (comprised of Na, K, Ca, Mg, Cl, SO4, HCO3/CO3) with the cladoceran, Ceriodaphnia dubia, a species known to be relatively sensitive to ion enrichment. This is the fourth in a series of manuscripts discussing the sensitivity of this species to major ions, with a specific focus of determining whether the principles governing acute response of this species to major ions also predict chronic responses. Results show this to be true, with acute-chronic ratios that are fairly consistent across different major ions, and responses to binary mixtures that show the same types of joint toxicity profiles as was observed previously for acute toxicity of major ions to this species. Mathematical models describing the response of these organisms were developed to predict the toxicity of major ion mixtures based on either chemical activity or chemical concentrations of ions in the mixture. These models showed good agreement with independent literature data on the chronic toxicity of major ion salts or ion mixtures to C. dubia. The datasets associated with this effort provide effect concentrations (EC20 and EC50) for 60 chronic toxicity tests conducted as part of this research, along with literature data extracted for comparison with model predictions. Data generated in this effort will inform efforts by OW, Regions, States, and Tribes to develop water quality standards/criteria for specific major ions (e.g., Cl, SO4). Perhaps more importantly, it provides part of the necessary scientific underpinning for developing standards/criteria that are sensitive to the specific composition of different sources of ion enrichment (e.g., produced water, mine drainage, irrigation return, industrial/municipal effluents) and can therefore support development of robust, integrated assessment tools. This dataset is associated with the following publication: Mount, D., R. Erickson, B. Forsman, T. Highland, R. Hockett, D. Hoff, C. Jenson, and T. Norberg-King. Chronic toxicity of major ion salts and their mixtures to Ceriodaphnia dubia. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 38(4): 769-783, (2019).

This dataset concerns the development of models for describing the acute toxicity of major ions to Ceriodaphnia dubia using data from single salt tests and binary mixture tests described in two other datasets under this research effort. It provides the data used in model development in the associated journal article. It also provides concentration-response data and associated general chemistry conditions for 3 experiments consisting of 14 toxicity tests on more complex mixtures of major ions based on data regarding elevated major ions in effluents and receiving waters, which was used for testing the models. . This dataset is associated with the following publication: Erickson, R., D. Mount, T. Highland, R. Hockett, D. Hoff, T. Norberg-King, and K. Peterson. The acute toxicity of major ion salts to Ceriodaphnia dubia: III. Mathematical models for mixture toxicity. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 1-13, (2017).

This dataset concerns the development of models for describing the acute toxicity of major ions to Ceriodaphnia dubia using data from single salt tests and binary mixture tests described in two other datasets under this research effort. It provides the data used in model development in the associated journal article. It also provides concentration-response data and associated general chemistry conditions for 3 experiments consisting of 14 toxicity tests on more complex mixtures of major ions based on data regarding elevated major ions in effluents and receiving waters, which was used for testing the models. . This dataset is associated with the following publication: Erickson, R., D. Mount, T. Highland, R. Hockett, D. Hoff, T. Norberg-King, and K. Peterson. The acute toxicity of major ion salts to Ceriodaphnia dubia: III. Mathematical models for mixture toxicity. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 1-13, (2017).

This dataset provides concentration-response data and associated general chemistry conditions for 29 experiments consisting of 209 tests regarding the acute toxicity of binary mixtures of major ions to Ceriodaphnia dubia; it also provides LC50 estimates and the estimated ion mixtures at the LC50 for each toxicity test. This dataset is associated with the following publication: Erickson, R., D. Mount, T. Highland, R. Hockett, D. Hoff, C. Jenson, T. Norberg-King, and K. Peterson. The acute toxicity of major ion salts to Ceriodaphnia dubia. II. Empirical relationships in binary salt mixtures. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 36(6): 1525-1537, (2017).

This dataset provides concentration-response data and associated general chemistry conditions for 29 experiments consisting of 209 tests regarding the acute toxicity of binary mixtures of major ions to Ceriodaphnia dubia; it also provides LC50 estimates and the estimated ion mixtures at the LC50 for each toxicity test. This dataset is associated with the following publication: Erickson, R., D. Mount, T. Highland, R. Hockett, D. Hoff, C. Jenson, T. Norberg-King, and K. Peterson. The acute toxicity of major ion salts to Ceriodaphnia dubia. II. Empirical relationships in binary salt mixtures. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 36(6): 1525-1537, (2017).

Data, associated metadata, and calculation tools.. This dataset is not publicly accessible because: Data is controlled by Proctor and Gamble, and is available upon request. It can be accessed through the following means: Available from the upon request from Kristin Connors (connors.ka@pg.com). Format: Data, associated metadata, and calculation tools. This dataset is associated with the following publication: Connors, K., J. Brill, T. Norberg-King, M. Barron, G. Carr, and S. Belanger. Daphnia magna and Ceriodaphnia dubia Have Similar Sensitivity in Standard Acute and Chronic Toxicity Tests. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 41(1): 134-147, (2022).

Surface water toxicity data from the California Environmental Data Exchange Network (CEDEN). CEDEN is the California State Water Board's data system for surface water quality in California, and seeks to include all available statewide data (such as that produced by research and volunteer organizations). Data in CEDEN include field, sediment and water column data collected from freshwater, estuarine, and marine environments. Examples of data in CEDEN come from laboratory, physical and biological analyses and include data types associated with chemical, toxicological, field, bio-assessment, invertebrate, fish, and bacteriological assay assessments. The data resource "Surface Water Toxicity" contains two provisionally assigned values (“DataQuality” and “DataQualityIndicator”) to help users interpret the data quality metadata provided with the associated result. Zip files are provided for bulk data downloads (in csv or parquet file format), and developers can use the API associated with the "Surface Water Toxicity" (csv) resource to access the data. Example R code using the API to access the data can be found [here](https://gist.github.com/daltare/6185457d3d81ea59fe7c1730a7e40318). Users who want to manually download more specific subsets of the data can also use the CEDEN query tool, at: https://ceden.waterboards.ca.gov/AdvancedQueryTool