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The Carcinogenic Potency Project

Atrazine (CAS 1912-24-9)
SMILES, InChI and Structure are below.
Rats and Mice: Cancer Test Summary
Rat Target Sites Mouse Target Sites TD50 (mg/kg/day)
Male Female Male Female Rat Mouse
mgl hmo mgl ute no positive no positive 36.6m no positive

Key to the Table Above

Positivity: For each chemical with a positive (carcinogenic) experiment in the Carcinogenic Potency Database (CPDB), results are included on carcinogenic potency (TD50) in each species and target sites in males and females. Positivity is determined by an author’s opinion in a published paper. If all experimental results in the CDPB are negative in a sex-species group, “no positive” appears. If the CPDB has no experiments in the sex-species group, “no test” appears. The summary presents the strongest evidence of carcinogenicity in each group. If there are both positive and negative experiments in a sex-species, the negative results are ignored in this Summary Table.
Target Site Codes:   hmo = hematopoietic system. mgl = mammary gland. ute = uterus. Target sites are listed if any author of published experimental results concluded that tumors were induced in that organ by the test agent. If there is more than one positive experiment in a sex-species, target sites listed may be from more than one experiment, e.g. if liver and lung are both listed, then liver may have been a target in one experiment and lung in another.
TD50: Our standardized measure of carcinogenic potency, TD50, is the daily dose rate in mg/kg body weight/day to induce tumors in half of test animals that would have remained tumor-free at zero dose. Whenever there is more than one positive experiment in a species, the reported TD50 value is a Harmonic Mean calculated using the TD50 value from the most potent target site in each positive experiment.
Superscripts:   m = There is more than one positive experiment in the species, and TD50 values from each positive experiment are used in the calculation of the reported Harmonic mean of TD50.

The Carcinogenic Potency Database (CPDB) is a unique and widely used international resource of the results of 6540 chronic, long-term animal cancer tests on 1547 chemicals. The CPDB provides easy access to the bioassay literature, with qualitative and quantitative analyses of both positive and negative experiments that have been published over the past 50 years in the general literature through 2001 and by the National Cancer Institute/National Toxicology Program through 2004. The CPDB standardizes the diverse literature of cancer bioassays that vary widely in protocol, histopathological examination and nomenclature, and in the published author’s choices of what information to provide in their papers. Results are reported in the CPDB for tests in rats, mice, hamsters, dogs, and nonhuman primates.

For each experiment, information is included on species, strain, and sex of test animal; features of experimental protocol such as route of administration, duration of dosing, dose level(s) in mg/kg body weight/day, and duration of experiment; experimental results are provided on target organ, tumor type, and tumor incidence; carcinogenic potency (TD50) and its statistical significance; shape of the dose-response, author’s opinion as to carcinogenicity, and literature citation.

Only tests with dosing for at least ¼ the standard lifespan of the species and experiment length at least ½ the lifespan are included in the CPDB. Only routes of administration with whole body exposure are included. Doses are standardized, average dose rates in mg/kg/day. A description of methods used in the CPDB to standardize the diverse literature of animal cancer tests is presented for: 1) Criteria for inclusion of experiments 2) Standardization of average daily dose levels and 3) TD50 estimation for a standard lifespan. See Methods for other details.

TD50 provides a standardized quantitative measure that can be used for comparisons and analyses of many issues in carcinogenesis. The range of TD50 values across chemicals that are rodent carcinogens is more than 100 million-fold. More than half the chemicals tested are positive in at least one experiment.

A plot of all results on each experiment in the CPDB for this chemical is presented below. These results are the source information for the Cancer Test Summary table above.

Atrazine: All Experiments and Citations in CPDB

The definition of each code in the plot below will appear in a pop-up window when the field name in the header line is clicked, e.g., Strain, Site, Path. Each numbered line starts a new experiment and reports protocol information in black. Average daily dose-rates per kg body weight per day are in green. Remaining lines report experimental results in blue.

Abbreviations of fields in header line: # = the line number in the plot of all CPDB chemicals; Xpo = duration of dosing; Xpt = duration of experiment; Site = tissue; Path = tumor type; DR = dose-response; AuOp = author’s opinion about carcinogenicity; LoConf, UpConf = confidence limits (99%) on TD50; Inc = tumor incidence for each dose group.

See Guide to reading the plot for details on each field, using an example of one experiment.

See Help to improve readability, or to fit the plot onto the screen or a printed page.

Chemical (Synonym) CAS
# Species Sex Strain Route Xpo+Xpt PaperNum        0 Dose  1 Dose 2 Dose  3 Dose          Literature Reference or NCI/NTP:Site Path
Site Path Notes   TD50  DR Pval    AuOp LoConf UpConf   Cntrl   1 Inc  2 Inc   3 Inc                                                        Brkly Code

ATRAZINE 1912-24-9 503 M f b6a orl 76w76 1244 0 11.1mg Innes;ntis,1968/1969 lun ade evx no dre P=1. - 12.4mg n.s.s. 1/17 1/17 liv hpt evx no dre P=1. - 20.7mg n.s.s. 0/17 0/17 tba mix evx 58.8mg P<.7 - 7.41mg n.s.s. 2/17 3/17 504 M m b6a orl 76w76 1244 0 10.3mg lun ade evx 28.2mg P<.4 - 5.90mg n.s.s. 2/18 4/18 liv hpt evx no dre P=1. - 20.4mg n.s.s. 1/18 0/18 tba mix evx 54.6mg P<.7 - 6.40mg n.s.s. 3/18 4/18 505 M f b6c orl 76w76 1244 0 11.1mg liv hpt evx no dre P=1. - 22.0mg n.s.s. 0/16 0/18 lun mix evx no dre P=1. - 22.0mg n.s.s. 0/16 0/18 tba mix evx 71.0mg P<.3 - 11.6mg n.s.s. 0/16 1/18 506 M m b6c orl 76w76 1244 0 10.3mg liv hpt evx 15.0mg P<.02 - 5.16mg n.s.s. 0/16 4/18 lun mix evx no dre P=1. - 20.4mg n.s.s. 0/16 0/18 tba mix evx 9.29mg P<.004 - 3.75mg 56.8mg 0/16 6/18 507 M f cd1 eat 78w78 2364m 0 1.30mg 39.0mg Stevens;jtxe,56,69-109;1999 lun mix es * P<.4 - n.s.s. 2/55 3/58 8/60 5/59 liv mix es no dre P=1. - 8.39mg n.s.s. 0/55 0/58 0/60 0/59 508 M f cd1 eat 78w78 2364n 0 1.30mg 39.0mg lun mix es 7.55gm * P<.6 - 1.15gm n.s.s. 2/60 1/59 2/60 4/60 2/60 liv hpa es no dre P=1. - 8.53mg n.s.s. 1/60 0/59 0/60 0/60 0/60 509 M m cd1 eat 78w78 2364m 0 1.20mg 36.0mg lun mix e 1.16gm Z P<.9 - 59.3mg n.s.s. 6/60 12/57 9/56 (3/55) liv mix e no dre P=1. - n.s.s. 1/60 2/57 3/56 0/55 510 M m cd1 eat 78w78 2364n 0 1.20mg 36.0mg lun mix e 1.99gm * P<.3 - n.s.s. 10/59 5/60 7/60 8/60 11/58 liv mix e no dre P=1. - 67.5mg n.s.s. 15/59 16/60 13/60 (4/60 2/58) 511 R f f34 eat 24m24 2362 0 .500mg 3.50mg 10.0mg 20.0mg Stevens;jtxe,56,69-109;1999/Wetzel 1994/ Thakur 1998 mgl mix e * P<.2 - 48.9mg n.s.s. 4/60 5/60 7/60 10/60 8/59 --- mnl e * P<.8 - 52.3mg n.s.s. 8/60 18/60 14/60 11/60 15/60 liv hpa e 1.14gm * P<.5 - n.s.s. 0/60 1/60 0/60 1/60 1/60 liv hpc e 3.71gm * P<.9 - n.s.s. 0/60 1/60 1/60 0/60 1/60 512 R f f34 eat 52w52 2363m 0 3.50mg 20.0mg mgl mix ekr no dre P=1. - 1.53mg n.s.s. 0/10 0/10 0/10 513 R f f34 eat 65w65 2363n 0 3.50mg 20.0mg mgl mix ekr no dre P=1. - 2.40mg n.s.s. 0/10 0/10 0/10 514 R f f34 eat 78w78 2363o 0 3.50mg 20.0mg mgl mix ekr no dre P=1. - 3.45mg n.s.s. 0/10 0/10 0/10 515 R f f34 eat 24m24 2363r 0 3.50mg 20.0mg mgl mix er no dre P=1. - 40.5mg n.s.s. 3/10 2/10 0/10 516 R m f34 eat 24m24 2362 0 .400mg 2.80mg 8.00mg 16.0mg liv hpa e * P<.2 - 72.3mg n.s.s. 3/60 1/60 2/60 2/60 5/60 liv hpc e no dre P=1. - n.s.s. 0/60 0/60 1/60 0/60 0/60 517 R f f3l eat 28m29 1957 0 19.2mg 38.2mg Pinter;nplm,35,533-544;1990/pers.comm. ute mal ae * P<.09 + 77.3mg n.s.s. 7/45 10/52 14/45 --- mix ae * P<.2 + 60.4mg n.s.s. 12/44 16/52 22/51 --- leu ae * P<.2 87.9mg n.s.s. 8/44 10/52 15/51 --- lym ae * P<.5 n.s.s. 4/44 6/52 7/51 tba mal ae 30.0mg * P<.0005 + 18.0mg 77.1mg 21/50 40/53 44/55 518 R m f3l eat 29m29 1957 0 15.3mg 30.6mg --- mix ae 68.2mg * P<.06 28.6mg n.s.s. 22/47 26/47 32/48 --- leu ae * P<.1 42.4mg n.s.s. 13/47 21/47 21/48 mgl mix ae * P<.02 + n.s.s. 1/45 1/52 8/45 mgl ben ae * P<.03 + n.s.s. 1/45 1/52 7/45 --- lym ae * P<.7 n.s.s. 9/47 5/47 11/48 mgl mal ae 2.17gm * P<.3 n.s.s. 0/45 0/52 1/45 liv hpc ae 2.19gm * P<.3 n.s.s. 0/47 0/47 1/48 tba mal ae 33.6mg * P<.0005 + 19.5mg 96.2mg 24/56 30/55 43/53 519 R f sda eat 52w52 2360m 0 3.50mg 20.0mg Stevens;jtxe,56,69-109;1999/Wetzel 1994 mgl mix ekr no dre P=1. 6.04mg n.s.s. 1/10 1/9 1/10 520 R f sda eat 65w65 2360n 0 3.50mg 20.0mg mgl mix ekr no dre P=1. 11.1mg n.s.s. 4/10 5/10 1/10 521 R f sda eat 78w78 2360o 0 3.50mg 20.0mg mgl mix ekr 46.4mg * P<.8 4.26mg n.s.s. 5/10 6/10 6/10 522 R f sda eat 24m24 2360r 0 3.50mg 20.0mg mgl mix er 34.6mg * P<.5 6.26mg n.s.s. 6/10 4/9 7/10 523 R f sda eat 24m24 2361 0 3.50mg 20.0mg mgl mix ers 29.8mg * P<.2 - 10.4mg n.s.s. 46/60 34/59 49/60 mgl car ers 88.3mg * P<.2 - 28.3mg n.s.s. 17/60 13/59 22/60 524 R f sda eat 52w54 2646m 0 48.0mg Stevens;jtxe,56,69-109;1999/1994/Ciba-Geigy 1986 mgl adc ek 24.9mg P<.003 10.1mg 0/20 6/20 mgl mix ek 24.9mg P<.003 10.1mg 0/20 6/20 mgl fba ek 84.2mg P<.1 20.7mg n.s.s. 0/20 2/20 liv tum ek no dre P=1. 53.3mg n.s.s. 0/20 0/20 525 R f sda eat 25m25 2646n 0 .500mg 3.50mg 25.0mg 50.0mg mgl mix es 37.9mg * P<.0005 + 21.6mg 35/68 39/69 47/69 47/70 59/69 mgl adc es 79.2mg * P<.0005 + 44.4mg 15/68 16/69 27/69 27/70 37/69 mgl fba es 88.3mg * P<.009 + 41.7mg 3.54gm 29/68 29/69 36/69 39/70 43/69 mgl cas es 1.93gm * P<.04 n.s.s. 0/68 0/69 0/69 0/70 2/69 mgl ade es 1.93gm * P<.3 n.s.s. 1/68 0/69 1/69 1/70 2/69 liv hpc es no dre P=1. 1.04gm n.s.s. 0/70 1/70 1/70 0/70 0/70 liv hpa es no dre P=1. n.s.s. 1/70 1/70 2/70 1/70 0/70 526 R f sda eat 24m24 2647 0 1.25mg 2.50mg 3.50mg 20.0mg Stevens;jtxe,56,69-109;1999/Environmental Protection Agency 2000 mgl car rs 50.4mg * P<.02 + 21.5mg n.s.s. 11/60 18/60 20/60 12/60 25/60 mgl fba rs * P<.8 31.0mg n.s.s. 16/60 24/60 31/60 27/60 24/60 527 R m sda eat 52w54 2646m 0 38.4mg Stevens;jtxe,56,69-109;1999/1994/Ciba-Geigy 1986 liv tum ek no dre P=1. 42.7mg n.s.s. 0/19 0/20 528 R m sda eat 25m25 2646n 0 .400mg 2.80mg 20.0mg 40.0mg tes ict e * P<.04 n.s.s. 1/71 3/70 2/70 2/70 7/70 liv hpa e * P<.02 n.s.s. 0/71 0/70 1/70 2/70 3/70 liv hpc e no dre P=1. n.s.s. 3/71 2/70 0/70 1/70 2/70

Mutagenicity in Salmonella: negative
SMILES Code for Atrazine: ClC1=NC(=NC(=N1)NC(C)C)NCC
InChI Code for Atrazine: InChI=1/C8H14ClN5/c1-4-10-7-12-6(9)13-8(14-7)11-5(2)3/h5H,4H2,1-3H3,(H2,10,11,12,13,14)
Source for SMILES and InChI: USEPA Distributed Structure-Searchable Toxicity (DSSTox) Database
Chemical Structure for Atrazine: Chemical Structure
Source for structure: National Library of Medicine ChemIDPlus

See full CPDB Summary Table on 1547 chemicals. See Full CPDB for all results on 6540 experiments of 1547 chemicals.

A complete list of CPDB chemicals, which is searchable by name or by CAS number, is available here.

For a compendium of CPDB results organized by target organ, which lists all chemicals in each species that induced tumors in each of 35 organs, see Summary Table by Target Organ.

The CPDB is available in several formats that permit printing and downloading into spreadsheets and statistical databases.

  1. A plot of the CPDB presents results of 1547 experiments on 6540 chemicals in an easily readable format that has been used in publications of the CPDB.
  2. A Screen version plot for use on a single computer screen, with the same data.
  3. Excel version of the same data.
  4. Tab-separated versions of the same data, which can be easily read into databases.

A Supplementary Dataset gives details on dosing and survival for each experiment.

Relatively precise estimates of the lower confidence limit on the TD10 (LTD10) are readily calculated from the TD50 and its lower confidence limit, which are reported in the CPDB. For researchers and regulatory agencies interested in LTD10 values, we provide them in an Excel spreadsheet.

PDF versions of our publications of analyses using the CPDB are available, organized by year and by research topic.

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Last updated: October 3, 2007

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