Fate of Radiocarbon in Beef Steers Implanted with 14C-Diethylstilbestrol

Rumsey, T. S.; Oltjen, R. R.; Kozak, Agnieszka; Daniels, F. L.; Aschbacher, P. W.

doi:10.2527/jas1975.403550x

Cited by 13 publications

(12 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In terms of the residue curve, figure 8 shows how the use of implants reduces residue load. The generalized curves are based on labeled metabolism studies of Rumsey et al (1975aRumsey et al ( , 1975b and Aschbacher et al (1975). The darker lines project unmeasurable residue at 120 d and show that if DES is fed during a 120-d period (90-d treatment and 30-d withdrawal), residue load before withdrawal in liver tissue is approximately 17 ppb.…”

Section: Residue Curvementioning

confidence: 99%

See 1 more Smart Citation

Experimental Approaches to Studying Metabolic Fate of Xenobiotics in Food Animals

Rumsey¹

1983

Journal of Animal Science

Self Cite

View full text Add to dashboard Cite

The use of agricultural chemicals is an important aspect of animal production. Animal scientists have played an active and varied role in the recent and rapidly developed use of these chemicals. Although approval to use agricultural chemicals has always been based on both efficacy and end point residues, increased consumer concerns during the past one and one-half decades about the safety of these chemicals have caused greater awareness for the latter. In this regard, emphasis on the total residue curve of an agricultural chemical should serve as a tool that will help optimize dose rate on one hand and minimize end point residues on the other hand. Selection against lipophilic materials has resulted in a marked reduction in residue load. However, problems with lipophilic residues still exist, and knowledge about how to prevent or manage these residues in animals as well as fundamental knowledge about their absorption is needed. Continued emphasis on reducing residue load of hydrophilic chemicals through the use of devices such as implants, boluses and ear tags should have high priority as should research on the absorption and excretion mechanisms of these chemicals. There are two important areas of research that are needed to help us deal with end point residues in the future. One is better understanding of the toxicology of end point residues so we can move away from the concept of zero tolerance toward basing all of our guidelines for the use of a chemical on biological principles. The other is better understanding of the specific mode of action of the chemicals we use, which will permit more refined management of agricultural chemicals and a further assurance of safety.

show abstract

Section: Residue Curvementioning

confidence: 99%

“…Comparison of residue curves for oral and implanted diethylstilbestrol. Oral curve is based on data of Rumsey et al (1975a) and the light (---) implant curve is based on data of Aschbacher et al (1975) and Rumsey et al (1975b). The dark (--) implant curve represents an idealized curve.…”

Section: Residue Curvementioning

confidence: 99%

Experimental Approaches to Studying Metabolic Fate of Xenobiotics in Food Animals

Rumsey¹

1983

Journal of Animal Science

Self Cite

View full text Add to dashboard Cite

show abstract

“…Investigators at the U.S. Department of Agriculture (USDA) laboratories in Fargo, North Dakota, and in Beltsville, Maryland, have reported (1)(2)(3)(4) the results of studies in cattle given -radioactively labeled diethylstilbestrol (DES) both orally and by implantation. In one of these studies (2) it was determined by isotope dilution that 5 percent or more of the total radioactivity recovered from the implants used was in the form of labeled impurities.…”

mentioning

confidence: 98%

“…We report here the isolation and characterization of the principal radioactive impurity in the formulated material used in one of the USDA studies with DES implants (4). The labeled DES contained 14C in the terminal position of one ethyl group.…”

mentioning

confidence: 99%

“…In one of these studies (2) it was determined by isotope dilution that 5 percent or more of the total radioactivity recovered from the implants used was in the form of labeled impurities. As the daily absorption of these impurities is sufficient to account many times over for the total radioactivity content in the beef livers, and as most of the radioactivity in the livers was not in the form of DES or DES conjugates (4), the presence of labeled impurities in the DES formulation used is a matter of concern. The likelihood that the, same impurities may follow nonradioactive carriers added during isola- tic pseudo-DES (+j-DES) obtained by using the following instrument settings: ionizing potential, 70 ev; trap current, 60 ,ua; accelerating potential, 3.5 kv; and source temperature, 2500C.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Impurities in Labeled Diethylstilbestrol: Identification of Pseudodiethylstilbestrol

Tennent

Kouba

Ray

et al. 1976

Science

View full text Add to dashboard Cite

show abstract

Exposure to diethylstilbestrol during sensitive life stages: A legacy of heritable health effects

Reed

Fenton

2013

Birth Defects Research Pt C

154

View full text Add to dashboard Cite

Diethylstilbestrol (DES) is a potent estrogen mimic that was predominantly used from the 1940s to 1970s in hopes of preventing miscarriage in pregnant women. Decades later, DES is known to enhance breast cancer risk in exposed women, and cause a variety of birth related adverse outcomes in their daughters such as spontaneous abortion, second trimester pregnancy loss, preterm delivery, stillbirth, and neonatal death. Additionally, children exposed to DES in utero suffer from sub/infertility and cancer of reproductive tissues. DES is a pinnacle compound which demonstrates the fetal basis of adult disease. The mechanisms of cancer and endocrine disruption induced by DES are not fully understood. Future studies should focus on common target tissue pathways affected and the health of the DES grandchildren.

show abstract

Fate of Radiocarbon in Beef Steers Implanted with 14C-Diethylstilbestrol

Cited by 13 publications

References 4 publications

Experimental Approaches to Studying Metabolic Fate of Xenobiotics in Food Animals

Experimental Approaches to Studying Metabolic Fate of Xenobiotics in Food Animals

Impurities in Labeled Diethylstilbestrol: Identification of Pseudodiethylstilbestrol

Exposure to diethylstilbestrol during sensitive life stages: A legacy of heritable health effects

Contact Info

Product

Resources

About