Select "Chemicals", , from the Explore page. Select "Create Custom Group" upper left of page. Browse Chemicals by typing name of chemical of interest in open box and selecting those of interest hold down Ctrl to select multiples. The Group Summary output table will have chemicals from the selection that have test results extracted to ECOTOX, with the list of chemicals and associated records in the table.
You can also select "Records" at the top of the screen to view the records. Select "Change Plot Parameters" below the Custom button and select desired options. The Y-axis can be set to the continuous variables of Concentration or Duration. Download for Windows. Updated Date: Dec 15, Get Updates via Email Submit your info below to receive notifications when quarterly updates are available. Reproductive toxicity is an important regulatory endpoint.
It has been used synonymously with developmental toxicity. Other tests are usually required for substances produced or imported in quantities greater than or equal to tons per year.
Structures were available for of the compounds of which were considered to be toxic. The bioconcentration factor, BCF, has been defined as the ratio of the chemical concentration in biota to that in water at steady state, as a result of absorption via the respiratory surface Hamelink; Environmentally, the BCF describes the accumulation of pollutants partitioning from the aqueous phase into an organic phase typically fish and does not include uptake due to diet.
The BCF has no units, as seen by the equation below:. Here, the BCF and steady-state BCF are synonymous with steady-state occurring after the organism has been exposed for a sufficient length of time such that the ratio does not change substantially. Environmentally, there may be concern if a significant amount of a substance is concentrated in a local environment through dumping, spillage, production, etc.
In particular it has been suggested that the BCF could be used in a first tier risk assessment of secondary poisoning in wildlife and humans though dietary exposure. The number of fish suggested for the test ranges from to with each test being performed from 44 to days.
A literature data set of substances with experimentally measured data points was compiled and logBCF was modeled using ANNE methodology. Understanding biodegradation of chemicals in the environment is becoming an increasing concern. There are several assays available to classify if a compound is biodegradable. The compound of interest is mixed with sludge from several different geographical locations and then oxygen consumption is measured for the period of time based on the protocol.
Biological oxygen demand BOD and percent biodegradation are calculated via the following equations, where ThOD represents the theoretical oxygen demand. After removing all metal containing compounds and maintaining only a single stereoisomer or tautomer of duplicated compounds, compounds remained.
Beginning in , the Mid-Continent Ecology Division of the US Environmental Protection Agency tested a set of industrial compounds for lethal effects on Pimephales promelas, the fathead minnow.
Although relatively few pharmaceutical compounds appeared in the training set of this model, those molecules that do fall into its chemical space still have a high predictive confidence.
The model is best suited to aromatic, amine-rich, halogenated, or non-polar compounds. Another toxicity assay has been developed at the College of Veterinary Medicine at the University of Tennessee in the laboratory of Prof. Schultz Schultz Publicly available data from this assay was employed in a recent publication to assess various QSAR modeling approaches by different research groups Zhu et al, In that study, the dataset was partitioned into a training set provided to each of the modeling groups and two test sets the second test set being discovered after the study was initiated.
Using the same partitioning, we matched the best level of performance in both test sets as reported among individual models of that study. Hamelink JL. Toxicity Module What is the Toxicity Module? Chromosomal Abberations Another aspect of related toxicity are chromosomal aberrations CA — such a test is frequently used for the assessment of the in vitro genotoxic potential of chemicals and drugs.
Phospholipidosis Phospholipidosis is a lysosomal storage disorder characterized by the accumulation of phospholipids in the tissues of the body. Skin and Respiratory Sensitization A skin sensitizer is a compound or substance that induces cutaneous allergic reactions. In general, LR performs much better than LDA and seems to be more attractive for the prediction of the more toxic compounds, i.
In addition, model fit and regression diagnostics was done through the influence plot which reflects the hat-values, studentized residuals, and Cook's distance statistics of each sample. Overdispersion was also checked for the LR model.
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