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The Carcinogenic Potency Project

N-Methyl-N′-nitro-N-nitrosoguanidine (CAS 70-25-7)
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
eso smi sto smi sto no test smi 0.803m,v 2.03

Monkeys: Cancer Test Summary
Monkey Target Sites TD50
Rhesus Cynomulgus Rhesus Cynomulgus
no positive no test no positive no test

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:   eso = esophagus. smi = small intestine. sto = stomach. 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. v = Variation is greater than ten-fold among statistically significant (two-tailed p<0.1) TD50 values from different positive experiments.

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.

N-Methyl-N′-nitro-N-nitrosoguanidine: 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

N-METHYL-N'-NITRO-N-NITROSOGUANIDINE (MNNG) 70-25-7 3811 M f cb6 wat 27w52 2226m 0 10.4mg Ho;clet,91,177-183;1995/pers.comm. smi adc e 2.03mg P<.004 + .841mg 12.1mg 0/7 7/12 3812 M f cb6 wat 52w52 2226n 0 10.0mg smi adc e no dre P=1. 6.70mg n.s.s. 0/7 0/13 3813 P b rhe eat 23y23 2004 : 0 .964mg Adamson;ossc,129-156;1982/Thorgeirsson 1994/Dalgard 1997/ Thorgeirsson&Seiber pers.comm. liv hpa jw 3.03mg P<.06 .493mg n.s.s. 0/23 1/4 tba ben Wjw no dre P=1. 1.07mg n.s.s. 8/108 1/18 3814 R b alb wat 78w78 1571 0 13.2mg Tsung-Hsien;jnci,70,1067-1069;1983 for pam r 22.9mg P<.02 7.87mg n.s.s. 0/23 4/20 stg adc r 22.9mg P<.02 7.87mg n.s.s. 0/23 4/20 3815 R m alb wat 34w52 1778 0 2.83mg Gurkalo;bexb,101,833-837;1986 gam adc er .403mg P<.003 + .160mg 1.90mg 0/6 7/10 3816 R m bfm wat 52w52 196 0 4.15mg Bralow;onco,27,168-180;1973 stg ivc er no dre P=1. - 10.7mg n.s.s. 0/20 0/50 stg pvc er no dre P=1. - 10.7mg n.s.s. 0/20 0/50 3817 R f f34 eat 24m24 1954 0 1.00mg 2.00mg 4.00mg Fears;txih,4,221-255;1988 sto car es 1.44mg * P<.0005 + .961mg 2.25mg 1/119 8/24 16/24 20/24 liv hpc es 17.8mg * P<.0005 7.25mg 64.3mg 0/120 0/24 3/24 3/24 3818 R m f34 wat 12m29 1611m 0 .857mg Lijinsky;canr,44,447-449;1984 stg mix 1.42mg P<.0005 + .658mg 4.00mg 0/20 9/20 stg ade 2.38mg P<.003 + .963mg 12.4mg 0/20 6/20 stg adc 5.22mg P<.04 + 1.58mg n.s.s. 0/20 3/20 stg sar 16.5mg P<.3 + 2.69mg n.s.s. 0/20 1/20 liv nnd no dre P=1. 3.94mg n.s.s. 5/20 1/20 3819 R m f34 wat 12m24 1611n 0 1.02mg stg mix .592mg P<.0005 + .302mg 1.33mg 0/20 14/20 stg ade 1.65mg P<.002 + .708mg 6.27mg 0/20 7/20 stg sar 2.48mg P<.007 + .936mg 28.6mg 0/20 5/20 stg adc 3.19mg P<.02 + 1.10mg n.s.s. 0/20 4/20 liv nnd no dre P=1. 3.31mg n.s.s. 5/20 1/20 3820 R m f34 eat 24m24 1954 0 .800mg 1.60mg 3.20mg Fears;txih,4,221-255;1988 sto car es .724mg * P<.0005 + .486mg 1.11mg 0/119 14/24 18/23 22/24 liv hpc es no dre P=1. 2.19mg n.s.s. 1/120 0/24 0/23 0/24 3821 R m f3d wat 30w70 2278 0 2.14mg Tatematsu;jnci,78,771-777;1987/pers.comm. sto ade er 1.37mg P<.02 + .661mg n.s.s. 0/8 10/26 sto adc er 1.81mg P<.03 + .814mg n.s.s. 0/8 8/26 3822 R m sda wat 30w52 2141m 0 3.46mg Basso;zkko,118,441-446;1992 stg adc er 1.61mg P<.03 + .551mg n.s.s. 0/10 4/13 3823 R m sda wat 52w52 2141n 0 6.00mg stg adc er 1.12mg P<.0005 + .508mg 3.53mg 0/10 9/15 3824 R f wis wat 35w60 1105 0 2.33mg Tahara;zkko,100,1-12;1981 bil cye er .178mg P<.0005 73.1ug .411mg 0/5 19/20 stg cnd er 2.38mg P<.2 + .821mg n.s.s. 0/5 4/20 3825 R f wis wat 32w57 1726 0 1.59mg Yasui;canr,45,4763-4767;1985 duo adc r 6.38mg P<.5 + 1.04mg n.s.s. 0/5 1/20 stg adc r 6.38mg P<.5 + 1.04mg n.s.s. 0/5 1/20 3826 R m wis wat 77w77 199 0 3.30mg Sugimura;canr,30,455-465;1970 stg mix e .693mg P<.0005 + .289mg 2.05mg 0/6 10/12 stg ade e 1.13mg P<.003 + .480mg 5.31mg 0/6 8/12 stg adc e 3.06mg P<.06 + 1.04mg n.s.s. 0/6 4/12 liv hpa e 14.3mg P<.4 2.32mg n.s.s. 0/6 1/12 3827 R m wis wat 30w65 435 0 1.92mg Matsukura;jnci,61,141-143;1978 stg adc er .523mg P<.002 + .186mg 2.54mg 0/10 5/8 3828 R m wis wat 35w60 1105 0 2.04mg Tahara;zkko,100,1-12;1981 stg cnd er 2.09mg P<.2 + .510mg n.s.s. 0/5 2/10 bil cye er no dre P=1. 1.40mg n.s.s. 0/5 0/10 3829 R m wis wat 32w87 1475 0 .366mg 1.52mg Arffmann;jnci,67,1071-1075;1981 git mix e .581mg * P<.0005 + .366mg 1.00mg 0/30 10/30 20/30 liv tum e no dre P=1. 1.28mg n.s.s. 0/30 0/30 0/30 3830 R m wis wat 28w58 1678 0 2.90mg Domellof;ajsu,142,551-554;1981 git adc r .810mg P<.0005 + .444mg 1.92mg 0/12 16/30 smi adc r 1.21mg P<.003 .617mg 4.60mg 0/12 12/30 stg adc r 4.31mg P<.1 1.49mg n.s.s. 0/12 4/30 3831 R m wis wat 30w54 1724m 0 4.68mg Morishita;clet,17,347-352;1983/pers.comm. duo tum er 3.44mg P<.1 + .839mg n.s.s. 0/8 2/9 3832 R m wis wat 26w52 1724n 0 2.50mg git mix er 1.60mg P<.04 + .549mg n.s.s. 0/12 4/17 duo tum er 2.21mg P<.07 .665mg n.s.s. 0/12 3/17 stg tum er 7.06mg P<.3 + 1.15mg n.s.s. 0/12 1/17 3833 R m wis wat 26w52 1724o 0 2.50mg git mix er 1.92mg P<.04 + .827mg n.s.s. 0/12 7/35 stg mix er 2.28mg P<.06 + .927mg n.s.s. 0/12 6/35 duo tum er 7.28mg P<.3 1.79mg n.s.s. 0/12 2/35 3834 R m wis wat 32w57 1726 0 1.39mg Yasui;canr,45,4763-4767;1985 duo adc r 2.72mg P<.4 + .668mg n.s.s. 0/5 2/20 3835 R m wis wat 75w75 1822 0 2.13mg Fujii;nutc,9,185-193;1987 duo adc e .910mg P<.0005 + .505mg 1.85mg 0/30 17/30 gam adc e 5.31mg P<.02 + 1.83mg n.s.s. 0/30 4/30 eso sqc e 11.0mg P<.1 + 2.71mg n.s.s. 0/30 2/30 liv tum e no dre P=1. 6.86mg n.s.s. 0/30 0/30 tba mix e no dre P=1. .764mg n.s.s. 20/30 20/30 3836 R m wis wat 28w52 2124 0 1.08mg 2.15mg 2.77mg Zaidi;carc,14,1561-1567;1993 pyl mix sv .284mg * P<.0005 + .195mg .709mg 0/10 16/25 20/24 13/22 pyl mal sv .410mg * P<.0005 + .274mg .955mg 0/10 10/25 18/24 11/22 pyl adc sv .428mg * P<.0005 + .285mg 1.06mg 0/10 10/25 17/24 11/22 duo mal sv .516mg * P<.01 + .339mg 33.9mg 0/10 11/25 15/24 8/22 duo adc sv .584mg * P<.007 + .376mg 8.58mg 0/10 9/25 15/24 7/22 liv ccy sv 4.58mg * P<.2 1.74mg n.s.s. 0/10 1/25 1/24 3/22 for mix sv 5.79mg * P<.3 2.00mg n.s.s. 0/10 1/25 1/24 2/22 duo lei sv 22.8mg * P<.8 2.92mg n.s.s. 0/10 1/25 0/24 1/22 duo ade sv 23.7mg * P<.4 3.85mg n.s.s. 0/10 0/25 0/24 1/22 duo cas sv no dre P=1. 4.27mg n.s.s. 0/10 1/25 0/24 0/22 pyl ade sv no dre P=1. 1.29mg n.s.s. 0/10 6/25 2/24 2/22 3837 R m wky wat 30w60 2122 0 1.25mg Tatematsu;carc,14,1415-1419;1993 gam adc er .895mg P<.04 + .268mg n.s.s. 0/10 3/11 3838 R m wmf wat 52w52 196 0 4.15mg Bralow;onco,27,168-180;1973 stg ivc er 6.75mg P<.2 1.66mg n.s.s. 0/16 2/20 3839 R m wsr wat 52w52 196 0 4.15mg stg ivc er 1.03mg P<.0005 + .684mg 1.63mg 0/40 37/74 stg pvc er 2.72mg P<.0005 + 1.54mg 5.91mg 0/40 17/74

Mutagenicity in Salmonella: positive
SMILES Code for N-Methyl-N′-nitro-N-nitrosoguanidine: N=C(N(N=O)C)N[N+](=O)[O-]
InChI Code for N-Methyl-N′-nitro-N-nitrosoguanidine: InChI=1/C2H5N5O3/c1-6(5-8)2(3)4-7(9)10/h1H3,(H2,3,4)
Source for SMILES and InChI: USEPA Distributed Structure-Searchable Toxicity (DSSTox) Database
Chemical Structure for N-Methyl-N′-nitro-N-nitrosoguanidine: 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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