Implants carcinogenicity

The main disadvantages of induced tumours for detecting antitumour activity are the difficulties involved in obtaining sufficient numbers of animals for testing at the same time, and the removal of the implanted carcinogen after tumour induction. 

In summary, preliminary results from two animal models (rabbit and mouse) indicate that poly(N-palmitoylhydroxyproline ester) elicits a very mild, local tissue response that compares favorably with the responses observed for established biomaterials such as medical grade stainless steel or poly(lactic acid)/poly(glycolic acid) implants. At this point, additional assays need to be performed to evaluate possible allergic responses, as well as systemic toxic effects, carcinogenic, teratogenic, or mutagenic activity, and adaptive responses. 

Bonser GM, Bradshaw L, Clayson DB et al (1956) A further study on the carcinogenic properties of ortho-hydroxyamines and related compounds by bladder implantation in the mouse. Br J Cancer 10 539-546... 

Diethylstilbestrol, mentioned in Chapters 5 and 9 as a synthetic estrogen that is also a human carcinogen, was used in the United States from the 1950s until 1979 as a growth promoter in sheep and cattle. Small amounts of this drug, added to animal feed or implanted in the flesh of animals ears, increase feed efficiency, and it was very widely used for this purpose. 

Zeranol does not appear to have carcinogenic activity (5). It is licensed for use as an implant pellet in beef cattle and lambs (Table II) where it has about 30 to 50 percent of the activity of diethylstibestrol (6). 

Chromite ore roast mixed with sheep fat implanted intrapleurally in rats produced sarcomas coexisting with squamous cell carcinomas of the lungs the same material implanted in the thigh of rats produced fibrosarcomas/ However, the lARC concluded that these studies were inadequate to fully evaluate the carcinogenicity of this compound/ Other animal studies have found no increase in the incidence of tumors with chromium metal and chromite ore/ The lARC has determined that there is inadequate evidence in humans and animals for the carcinogenicity of metallic chromium and chromium(III) compounds. 

Chronic animal studies have also yielded varying results. Intratracheal implantation of lead chromates in rats failed to significantly increase the carcinogenic response after 2 years. Intrapleural administration caused a 9% incidence of lung tumors in rats within 19-21 months. Intramuscular injection resulted in lymphomas, renal tumors, fibrosarcomas, and rhabdomyosarcomas at the site of injection in rats. ... 

PTFE implanted subcutaneously in animals has induced local sarcomas, suggesting a foreign body reaction rather than chemical carcinogenesis the lARC has determined that there is insufficient evidence to assess the carcinogenic risk, especially with regard to occupational exposure in humans. ... 

K. -W. Naujack, U. Mohr, and H. Ernst, Contribution of Polycyclic Aromatic Hydrocarbons and Nitro-Derivatives to the Carcinogenic Impact of Diesel Engine Exhaust Condensate Evaluated by Implantation into the Lungs of Rats, Cancer Lett., 37, 173-180 0 987). 

SAFETY PROFILE Confirmed human carcinogen with experimental tumorigenic and carcinogenic data. Poison by ingestion and implant routes. Mutation data reported. A powerful oxidizer. See also CHROMIUM COMPOUNDS and CALCIUM COMPOUNDS. 

SAFETY PROFILE Questionable carcinogen with experimental tumorigenic data by implant. See also POLYMERS. When heated to decomposition it emits acrid smoke and irritadng fumes. 

SAFETY PROFILE Confirmed carcinogen with experimental carcinogenic, neoplastigenic, tumorigenic, and teratogenic data. A poison by intraperitoneal and subcutaneous routes. Human reproductive effects by implantation spermatogenesis and impotence. Mutation data reported. A steroid dmg for the treatment of menopause and ovariectomy symptoms. When heated to decomposition it emits acrid smoke and irritating fumes. 

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