Jump to main content.


CAS Number: 57-62-5
Synonyms: 7-chlorotetracycline, Aureomycin, CLTC, CTC, Chlorotetracyline, Chlortetracyclin
Contaminant Type: Chemical

Chlortetracycline, a member of tetracycline family, is a broad-spectrum antibiotic that is commonly given to poultry, swine, and livestock. Chlortetracycline may lead to the development of antibiotic resistance [1327]; other potential adverse effects are unknown.

Chlortetracycline can be used to prevent, control, and treat animal health problems as well as enhance growth rates in chickens, turkeys, ducks, swine, calves, beef cattle, and other animals [1326]. It has been in clinical use in 1948. [1348]

Chlortetracycline enters the environment primarily through the application of animal manure to fields. [1529] Chlortetracycline appears to be retained in the top soil layers after land application. [1350] The compound may also dissolve or associate with particles in surface runoff. The solubility of chlortetracycline is approximately 500 mg/L; values of soil/water partitioning depend on the type of soil and on the type of antibiotic formulation. [1326]

Chlortetracycline has been shown to be relatively persistent in soil. [1529] Primary attenuation mechanisms include hydrolysis, biodegradation and photolysis in sunlight-exposed soils. [1529, 1325] One study of chlortetracycline degradation from chicken feces over a 30-day period showed temperature dependence, with no significant degradation at 4 °C, 12% of the original concentration (5.6 mg/kg) degradation at 20 °C and 56% degradation at 30 °C. [1349]

The stability of chlortetracycline in water depends on pH, temperature, light, and other parameters. [1530] In a study of soil interstitial water and milliQ water, light appeared to generally accelerate chlortetracycline degradation, as did increasing the pH (from 3.0 to 9.0) and the temperature (from 6 °C to 20 °C). [1530] Half-lives of chlortetracycline at 20 °C and pH 8.5 were less than 10 days. [1530]

Chlortetracycline is not currently regulated in drinking water by U.S. Environmental Protection Agency. [1351] Toxicity information for chlortetracycline is limited, and whether it is carcinogenic or endocrine disruptive is unknown. [980]

Chlortetracycline is often analyzed by liquid chromatography (LC) combined with mass spectrometry (MS), such as LC/MS, LC-MS/MS, LC/ESI (electospray ionisation)-MS. [1527,1327, 1530, 1352]

Chlortetracycline is not often detected in water sources, perhaps due to its absorption to soil or bounding with other chemicals. [1354] Several studies focusing on the occurrence of antibiotics did not detect chlortetracycline in treated wastewater, surface water, and groundwater in the U.S., Canada, and Germany. [1352, 1353 and 1354]  However, one study detected chlortetracycline in 2.4% of 84 samples from streams in the U.S. using a LC/MS-ESI method developed by the U.S. Geological Survey (the method report limit was 0.10 µg/L). [1355] However, chlortetracycline was not detected using another LC/MS-ESI method in the same study (the method report limit was 0.05 µg/L). [1355] One study showed chlortetracycline detections in top soil (0 to 30 cm below ground surface) ranging from 4.6 – 7.3 µg/kg with no detections in soil layers below 30 cm. [1350]

Date of Literature Search: August 2009

980 Pesticide Action Network North America; 2009; Chlortetracycline - identification, toxicity, use, water pollution potential, ecological toxicity and regulatory information; http://www.pesticideinfo.org/Detail_Chemical.jsp?Rec_Id=PC33593; As posted on September 16, 2009. Pesticide Action Network North America
1326 Hoese, A., Clay, S.A., Clay, D.E., Oswald, J., Trooien, T., Thaler, R. and Carlson, C.G.; 2009; Chlortetracycline and tylosin runoff from soils treated with antimicrobial containing manure; J. Environ. Sci. & Health Part B; 44:4:371
1327 Davis, J.G., Truman, C.C., Kim, S.C., Ascough, J.C. II and Carlson, K.; 2006; Antibiotic transport via runoff and soil loss; J. Environ. Qual.; 35:66:2250
1348 Giguere, S.; 2007; Tetracyclines and Glycylcyclines; Antimicrobial Therapy in Veterinary Medicine, Fourth Edition; Chapter 14. pp. 231-233, Blackwell Publishing.
1349 Gavalchin, J. and Katz, S.E.; 1994; The persistence of fecal-borne antibiotics in soil; Journal of AOAC International; 77:2:481
1350 Hamscher, G., Sczesny, S., Hoper, H. and Nau, H.; 2002; Determination of persistent tetracycline residues in soil fertilized with liquid manure by high-performance liquid chromatography with electrospray ionization tandem mass spectrometry; Anal. Chem.; 74:7:1509
1351 USEPA; 2009; Drinking water contaminants; http://www.epa.gov/safewater/contaminants/index.html; As posted on August 10, 2009. USEPA Office of Ground Water and Drinking Water, Washington, D.C.
1352 Karthikeyan, K.G. and Meyer, M.T.; 2006; Occurrence of antibiotics in wastewater treatment facilities in Wisconsin, USA; Sci. of the Total Envir.; 361:1-3:196
1353 Miao, X.S., Bishay, F., Chen, M. and metcalfe, C.D.; 2004; Occurrence of antimicrobials in the final effluents of wastewater treatment plants in Canada; Env. Sci. & Tech.; 38:13:3533
1354 Hirsch, R., Ternes, T., Haberer, K. and Kratz, K.L.; 1999; Occurrence of antibiotics in the aquatic environment; Sci. of the Total Envir.; 225:1-2:109
1355 Kolpin, D.W., Furlong, E.T., Meyer, M.T., Thurman, E.M., Zaugg, S.D., Barber, L.B. and Buxton, H.T.; 2002; Pharmaceuticals, hormones, and other organic wastewater contaminants in U.S. streams, 1999-2000: a national reconnaissance; Env. Sci. & Tech.; 36:6:1202
1527 Choi, K.J., Son, H.J. and Kim, S.H.; 2007; Ionic treatment for removal of sulfonamide and tetracycline classes of antibiotic; Science of the Total Environment; 387:1-3:247
1529 Werner, J.J., McNeill, K. and Arnold, W.A.; 2009; Photolysis of chlortetracycline on a clay surface; J. Agric. Food Chem.; 57:15:6932
1530 Soeborg, T., Ingerslev, F. and Halling-Sorensen B.; 2004; Chemical stability of chlortetracycline and chlortetracycline degradation products and epimers in soil interstitial water; Chemosphere; 57:10:1515

Local Navigation

Jump to main content.