Water Resources of the United States
Chemical Mixtures Software
- The chemical mixtures software is a collection of computer programs for investigating the composition, occurrence, distribution, and potential toxicity of chemical mixtures. The software is designed to
assist with selecting specific mixtures for future research, identifying the causes for the occurrence of specific mixtures, and discovering the effects of mixtures.
- Version 1.0 -- 2013/07/01
Initial public release which includes four Perl programs: qwmixtures.pl, qwmixtrace.pl, qwmixbq.pl, and qwmixsort.pl, and published documentation.
- Version History
Four programs comprise the chemical-mixtures software. You may save each program individually from the 4 links below, or save all 4 at once with in a unix tar file.
The four programs are:
- qwmixtures.pl (vers 1.0) - is used to study mixture occurrence, and enumerates the mixtures in an analytical data file and sorts the mixtures by frequency of occurrence.
- qwmixtrace.pl (vers 1.0) - is used to study mixture distribution, and traces mixtures to the samples in which the mixtures were detected. These distributions may be spatial, temporal, or some other variable (such as chemical usage patterns).
- qwmixbq.pl (vers 1.0) - is used to study potential toxicity of mixtures, and prepares benchmark-normalized concentration sums for each sample.
- qwmixsort.pl (vers 1.0) - is used by the other programs for sorting files.
- qwmix_4scripts.tar Unix tar file containing all 4 programs.
Dependencies and installation procedures are described in the documentation.
The mixture software should be usable on a variety of computer systems. The programs were written in the Perl programming language (version 5.10.1) and were developed and tested on a 64-bit Sun V440 with 8-GB of memory running SunOS 5.10 (Sun1, in graph). The programs have also been run successfully using:
- a Lenovo with 64-bit Intel G630 processors and 6-GB of memory running Microsoft Windows 7,
- a 64-bit Sun V240 with 16-GB of memory running SunOS 5.10 (Sun2 in graph), and
- an IBM 3650 with 2 64-bit Intel E5640 processors and 48-GB of memory running RedHat Linux version 2.6.32.
The following data sets may be useful for verifying proper installation of the software and configuring run-time variables.
- 20.rdb -- an input data set with analytical results for single sample with 20 detected compounds. Output files: report.txt, mixtures.rdb.gz (2.5 MB), and raw.rdb.gz (2.4 MB).
- 26.rdb -- an input data set with analytical results for single sample with 26 detected compounds. Output files: report.txt, mixtures.rdb.gz (161 MB), and raw.rdb.gz (158 MB).
- gila.rdb -- an input data set retrieved from NWISWeb with trace-element results for groundwater samples from Gila county, Arizona. Output files: report.txt, mixtures.rdb.gz, raw.rdb.gz (2.4 MB), trace for a mixture of fluoride and aluminum in mt.gz, and potential toxicities in bq.rdb.gz.
- benchmarks.rdb -- a file containing benchmark data for contaminants in water, consisting of Maximum Contaminant Levels and Health-Based Screening Levels.
The purposes, installation, and usage of the software are
documented in U.S. Geological Survey Scientific Investigations Report 2013-5030:
Scott, J.C., Skach, K.A., and Toccalino, P.L. , 2013, Software for analysis of chemical mixtures - composition, occurrence, distribution, and possible toxicity: U.S. Geological Survey Scientific Investigations Report 2013-5030, 27 p., 2 apps.,
Level of support to expect:
Users are encouraged to report bugs and send ideas for future enhancements.
Example commands, appendices with software error and warning messages, and
installation tips are provided in the documentation.
Example datasets are provided on this web site.
Enhancements to add, and Bugs to fix... someday ...
|In date ||done in Version ||Suggestion From ||Description of Need |
|July 29, 2014 || ||Jeff Swartout, EPA, Cincinnati |
| Enhancement: Add a confidence interval around the expected occurrence percentage (of qwmixtures.pl) based on the sample size and the binomial distribution.|
Points of contact for the chemical mixtures software:
Laura Bexfield, firstname.lastname@example.org
USGS New Mexico Water Science Center
U.S. Geological Survey
Office of Water Quality
412 National Center
12201 Sunrise Valley Drive
Reston, VA 20192
The time required to run the programs may be hours or days, and will vary depending on the size of the problem and the computing hardware.
Use of trade names is for identification purposes and does not imply endorsement by the U.S. Geological Survey. Perl and applicable Perl packages are free software, made available under an Artistic License.
Although these programs have been used by the USGS, no warranty, expressed or implied, is made by the USGS or the United States Government as to the accuracy and functioning of the programs and related program materials nor shall the fact of distribution constitute any such warranty, and no responsibility is assumed by the USGS in connection therewith.