The Physical Properties Database (PHYSPROP)

The Physical Properties Database (PHYSPROP) contains chemical structures, names and physical properties for over 25,250 chemicals. Physical properties are collected from a wide variety of sources, and include experimental, extrapolated, and estimated values for melting point, boiling point, water solubility, octanol-water partition coefficient, vapor pressure, pKa, Henry's law constant, and OH rate constant in the atmosphere.

This file has been actively built by SRC over the last two decades. It started as a database of physical properties for chemicals being evaluated by SRC for the Hazardous Substances Data Bank (HSDB), available from the National Library of Medicine (NLM). Since then, it has also been used as a repository for physical and chemical property data that were used to develop estimation methods for the EPI Suite™ software (owned by the US EPA; for more information and free download see http://www.epa.gov/oppt/exposure/docs/episuite.htm). Initially data were entered by junior and senior scientists using many sources for which the data had already been carefully evaluated (see Boethling RS, PH Howard and W Meylan. 2004.  Finding and estimating chemical property data for environmental assessment. Environ. Toxicol. Chem. 23: 2290-3308). Data were then checked by senior scientists as described for CHEMFATE. Additional quality control was performed by comparing measured values to estimated values from structure/property relationships (as a possible means of identifying outlying observations); and/or by comparing the values for one property (e.g. Henry’s Law constant) to estimates derived from other properties (e.g., the ratio of vapor pressure and water solubility in the case of Henry’s law constant - discussed in the preceding reference). This file is continually updated.

Try our On-Line Interactive Demo Version of PHYSPROP which retrieves data from the database of 25,000 compounds.

Currently, PHYSPROP contains the following number of experimental records: Melting Point (10120), Boiling Point (6629), Water Solubility (6340), Octanol-Water Partition Coefficient (13250), Vapor Pressure (2837), pKa (1652), Henry's Law Constant (1713), OH Rate (500).

PHYSPROP is available in ISISBase format (MDL Information Systems, Inc.). This program allows PHYSPROP to be searched by substructure, name fragment, or any of the physical properties. This is an excellent starter database for ISISBase users who need a base set of chemical structures and physical properties. PHYSPROP is also available in other formats (SD File, MS-Excel97, MS-Access, etc.).