The Subchronic Oral Toxicity of Ethane, 1,2-Bis(pentabromophenyl) (Saytex 8010) in Rats

2002 ◽  
Vol 21 (3) ◽  
pp. 165-170 ◽  
Author(s):  
M. L. Hardy ◽  
D. Margitich ◽  
L. Ackerman ◽  
R. L. Smith

Ethane, 1,2-bis(pentabromophenyl) (EBP; CAS no. 8452–53–9) dose levels of 0, 100, 320 and 1000 mg/kg/day administered to rats by gavage in corn oil for 90 consecutive days produced no compound-related clinical signs of systemic toxicity, ocular lesions, or alterations in urinalysis, clinical chemistry, and hematology values in the treated or recovery groups. No biologically or toxicologically significant differences were observed in body weights, body weight gains, and food consumption. Statistically significant differences were found between control and high-dose animals in mean absolute or relative liver weights. Histomorphological evaluation showed in male rats low-grade liver changes consisting of minimal to slight hepatocellular vacuolation (high-dose males) and minimal to slight centrilobular hepatocytomegaly (high- and possibly mid-dose males). These changes had resolved by the end of the 28-day recovery period. No treatment-related changes were found in the livers of female rats. No treatment-related histomorphologic changes were present in any of the other tissues examined in either sex, except for evidence of aspirated test article in individual rats. The 90-day EBP no-adverse-effect level in the rat was 1000 mg/kg/day, and was consistent with that of the preceding 28-day study (no-effect level 1250 mg/kg/day). EBP's lack of toxicity is likely related to poor bioavailability due to its high molecular weight and low solubility.

2008 ◽  
Vol 27 (3_suppl) ◽  
pp. 101-118 ◽  
Author(s):  
Eri Watanabe ◽  
Terutaka Kodama ◽  
Takeshi Masuyama ◽  
Shoji Tsubuku ◽  
Akira Otabe ◽  
...  

Dihydrocapsiate, (4-hydroxy-3-methoxybenzyl 8-methylnonanoate; CAS No. 205687-03-2) is a naturally occurring capsinoid compound found in nonpungent chili peppers. Although the safety of synthetically produced dihydrocapsiate has been previously evaluated, the purpose of this 13-week gavage toxicity study is to evaluate dihydrocapsiate produced with a slightly modified manufacturing process. Sprague-Dawley rats, 10 rats/sex/group, 6 weeks of age at study initiation, were administered the dihydrocapsiate daily by gavage at dose levels of 0 (vehicle), 100,300, or 1000 mg/kg/day. The rats were observed for antimortem and postmortem signs of toxicity, including changes in clinical signs, body weights, food consumption, water intake, ophthalmology, clinical pathology (clinical chemistry, hematology, urinalysis), tissue findings (macroscopic and microscopic examination), as well as organ weights. There were no changes observed in clinical signs, body weight, food consumption, water intake, ophthalmology, urinalysis, hematology, or blood chemistry that were attributable to the administration of dihydrocapsiate. The only change observed attributable to the dihydrocapsiate administration involved the liver and that change occurred only at the high dose (1000 mg/kg). Both sexes had an increase in organ weights, but this increase correlated with a change in histopathology (i.e., hepatocyte hypertrophy) only in the males. No dihydrocapsiate-related histopathological changes were observed in males at doses ≤300 mg/kg or in females at any of the doses tested (≤1000 mg/kg). It was concluded that the no observed adverse effect level (NOAEL) of dihydrocapsiate was 300 mg/kg/day for male rats and 1000 mg/kg/day for female rats in this 13 week gavage study.


2019 ◽  
Vol 8 (5) ◽  
pp. 686-695 ◽  
Author(s):  
Wenlong Xiao ◽  
Xiaoyang Wang ◽  
Chunmei Wang ◽  
Mi Wang ◽  
Chenzhong Fei ◽  
...  

Abstract Ethanamizuril is a novel triazine compound that exhibits remarkable anticoccidial activity. Owing to its pharmacological properties, this study was conducted to evaluate the acute and 30-day oral toxicity of ethanamizuril. In the acute study, ethanamizuril was administered once by oral gavage to mice and rats. The calculated LD50 values for mice and rats were 5776 and 4743 mg per kg b.w, respectively, but the LD50 value for male rats was higher than that of female rats. In the subchronic study, male and female rats were fed with diets supplemented with 0, 20, 60 or 120 mg kg−1 ethanamizuril for 30 days. Treatment related clinical signs of alopecia on the back and neck of the animals were observed in the 60 and 120 mg kg−1 dose groups from the third week of treatment. Significant differences in haematological and biochemical parameters as well as organ-to-body weight ratios were detected between the 60 and 120 mg kg−1 groups. Histopathological observations revealed that 60 and 120 mg kg−1 ethanamizuril could induce focal hepatocellular necrosis and split phase. Slight renal tubule protein casts in the kidneys and alveolar wall thickening in the lungs were also observed in the high dose groups of both genders. The dietary no-observed-adverse-effect level (NOAEL) of ethanamizuril for 30 days was 20 mg kg−1 feed.


1999 ◽  
Vol 18 (3) ◽  
pp. 173-176 ◽  
Author(s):  
Ralph I. Freudenthal ◽  
Richard T. Henrich

Fyrol PCF is a flame retardant chemical widely used to control the flam mability of rigid polyurethane foams and polyester foam systems. It has moderate acute toxicity and was shown to lack mu-tagenic activity. The present study was conducted to determine the toxicity of Fyrol PCF after repeated dietary exposure. Five groups, each consisting of 20 male and 20 female Sprague-Dawley rats, a diet containing either 0, 800, 2500, 7500, or 20,000 ppm Fyrol PCF for 90 days. Data collected include clinical observations, food consumption, body weights, organ weights, urinalysis, hematology, clinical chemistry, brain cholinesterase activity, and gross and microscopic pathology. The mean body weight of animals receiving 20,000 ppm was significantly lower than control values for most study weeks. No clinical signs were noted during cage-side observations. Liver weights were increased in male rats in all treatment groups, and in female rats in both the mid-and high-dose groups. No treatment-related histopathologic changes were observed in the livers of animals that 800, 2500, or 7500 ppm Fyrol PCF; however very mild periportal hepato-cellular swelling was seen in certain of the 20,000 ppm animals. Mean kidney weights were significantly greater in the male animals given 2500, 7500, and 20,000 ppm. Very mild cortical tubular degenerative changes were found in kidneys of male rats that 7500 ppm or 20,000 ppm and in female animals that ingested 20,000 ppm Fyrol PCF. An increase in the incidence of very mild thyroid follicular changes was found in the two highest dose groups. Fyrol PCF did not affect hematology or clinical chemistry parameters, nor did it significantly inhibit brain cholinesterase activity. None of the observed minimal treatment-related changes appear to have human relevance, because they occurred only at the highest doses used in the study. The no observable effect level in this study is 2500 ppm. Fyrol PCF demonstrated low subchronic toxicity in this study.


2016 ◽  
Vol 35 (5) ◽  
pp. 558-567 ◽  
Author(s):  
D. Schmitt ◽  
R. Levy ◽  
B. Carroll

In a subchronic toxicity study, administration of β-caryophyllene (BCP) oil by oral gavage to Wistar rats at dosages of 0, 150, 450, or 700 mg/kg/d for 90 days, including a 21-day recovery period, did not produce any significant toxicologic manifestations. The study design also included a 28-day interim sacrifice in the control and high-dose groups. The BCP oil test article was well tolerated as evidenced by the absence of major treatment-related changes in the general condition and appearance of the rats, neurobehavioral end points, growth, feed and water intake, ophthalmoscopic examinations, routine hematology and clinical chemistry parameters, urinalysis, and necropsy findings. The no observed adverse effect level was the highest dosage level administered of 700 mg/kg body weight/d for both male and female rats. The study was conducted as part of an investigation to examine the safety of BCP oil for its proposed use in medical food products.


2021 ◽  
Vol 12 ◽  
Author(s):  
John Turner ◽  
Albert Licollari ◽  
Emil Mihalcea ◽  
Aimin Tan

NAD+ is an abundant molecule in the body and vital to all living cells. NAD+ levels decline with age, and this decline correlates with age-related diseases. Therefore, sustaining NAD+ levels offers potential benefits to healthspan and longevity. Here we conducted toxicity studies to evaluate the safety of Restorin® NMN, a high purity form of the direct NAD+ precursor, β-nicotinamide mononucleotide (NMN). Based on the preliminary toxicity study and a 14-days repeated dose toxicity study at a higher dose level exposure, Restorin® NMN was administered orally to Sprague-Dawley rats for 91 days followed by a 14-days recovery period. The oral doses of 500, 1,000, and 2000 mg/kg/day were compared. There were no test item-related findings that could be considered adverse events in animals dosed at 500 mg/kg/day. The findings in the Restorin® NMN high dose group (2000 mg/kg/day) were similar to the reference item (Nicotinamide Riboside Chloride) dosed at 1740 mg/kg/day: reduced body weight, reductions in body weight gains, and diminished food consumption. In conclusion, the No-Observed-Adverse-Effect-Level (NOAEL) for Restorin® NMN is 1,000 mg/kg/day in female rats and 500 mg/kg/day in male rats, and the Low-Observed-Adverse-Effect-Level (LOAEL) for Resotrin® NMN is 2000 mg/kg/day.


2020 ◽  
Vol 36 (7) ◽  
pp. 502-513
Author(s):  
Işil Aydemir ◽  
Caner Özbey ◽  
Oktay Özkan ◽  
Şadiye Kum ◽  
Mehmet İbrahim Tuğlu

Bisphenol-A (BPA) used in the production of plastic materials is a temperature-soluble agent. It also has a steroid hormone-like activity; therefore, it poses a danger to human health. In our study, we aimed to investigate the effects of BPA on lymph node and spleen in male rats exposed to this agent during prenatal stage. The pregnant female rats were divided into four groups: control, sham, low dose (300 µg/kg BPA), and high dose (900 µg/kg BPA). BPA was dissolved in 1 mL of corn oil and administered to the pregnant rats every day during pregnancy. On the 21st and 45th day after the birth, male rats’ lymph node and spleen samples were taken and histopathological examination was performed. Samples were stained with hematoxylin and eosin to determine the general histological appearance, and with CD3 and CD20 immunohistochemically. The results of staining were evaluated by H-score, and statistical analysis was performed. In the samples, BPA applications were not found to cause significant tissue damage. But there was a significant decrease in the immunoreactivities of CD3 and CD20 after BPA applications in both 21st and 45th day samples. After high dose BPA administration, decreased CD3 immunoreactivity was statistically significant. It is thought that BPA does not cause histologically significant tissue damage, but it may impair organ function at cellular level. The investigation of molecules involved in organ function will be useful in revealing the mechanisms that will cause dysfunction.


1999 ◽  
Vol 18 (5) ◽  
pp. 337-352 ◽  
Author(s):  
Steve K. Teo ◽  
Nancy J. Trigg ◽  
Mary E. Shaw ◽  
J. Michael Morgan ◽  
Steve D. Thomas

The subchronic toxicology of thalidomide was determined in CD-1 mice and F344 rats. Animals (10/sex/dose) were orally dosed at 30,300, and 3000 mg/kg/day over 13 weeks. Control animals were given 1% carboxymethylcellulose. No thalidomide-related mortality occurred throughout the study. Some species and sex differences were seen. In mice, thalidomide had no effect on body weight, food consumption, ophthalmic function or clinical chemistry/hematology, but a dose-dependent orange-pink urine was observed in both sexes. The discoloration was probably due to chromogenic breakdown products of thalidomide. The only significant finding in the mouse study was dose-related hepatic centrilobular hypertrophy in the males. This appeared only at the highest dose in the females. The hypertrophy was correlated with increased liver weight for the high dose of both sexes suggesting enzyme induction. In rats, thalidomide produced lower body weights in both sexes compared to control with a dose-response more evident in males. Male rats dosed at 30, 300, and 3000 mg/kg had body weights that were 8, 11, and 19% below control weight just before necropsy. Corresponding female rats were only 6–7% below control weights at all dose levels. Lower food consumption was observed in male rats and varied between 6–13% below control with no dose-response. Decreased forelimb strength was noted in males and could be due to the lower body weights. Functional observational battery tests and histopathology of the sural nerve and lumbar spinal cord sections suggested that the rat did not develop thalidomide-induced peripheral neuropathy. Mild anemia and leukopenia were seen only in some treated males. A decrease in total and free T4 was more consistent in females. Both sexes had lower thymus weights with no histological correlate compared to control. The no-observed-adverse-effect level for mice and female rats were 3000 mg/kg and 30 mg/kg for male rats.


1992 ◽  
Vol 8 (6) ◽  
pp. 353-367 ◽  
Author(s):  
Christopher Bevan ◽  
William M. Snellings ◽  
Darol E. Dodd ◽  
Gerard F. Egan

Fischer 344 rats were exposed by inhalation to 0, 1, 5 or 50 ppm dicyclopentadiene (DCPD) vapor 6 hr/day, 5 days/week for 13 weeks, followed by a 13-week recovery period. Animals were euthanized following completion of exposure at 2, 6, or 13 weeks and at postexposure weeks 4 or 13. No mortality, overt signs, body weight changes, hematologic or clinical chemistry values were related to DCPD exposure. In the high-exposure male rats, relative liver weights were significantly increased but with no accompanying histopathologic changes. Exposure to DCPD produced adverse kidney effects in male, but not female, rats as evidenced by the excretion of epithelial cells in the urine. Histologic changes were localized to the proximal tubules of the kidney and included increased accumulation of protein droplets, regenerative epithelium, and the presence of intraluminal proteinaceous material. In addition, several alterations in renal function were observed. Urinary Na+ excretion rates were decreased and urinary K+ excretion rates were increased throughout the exposure period; however, glucose was not present in the urine, and creatinine clearance was normal. The ability of the kidney to concentrate urine was also impaired. After the recovery period, many of the treatment-related kidney effects were not observed, including the presence of hyaline droplets in the proximal tubules and epithelial cells in the urine. These findings indicate an overall low degree of systemic toxicity following sub-chronic inhalation exposure of dicyclopentadiene at exposure levels up to 50 ppm. The only effect that was observed was a male rat-specific nephropathy that is characteristic of the hyaline droplet nephropathy produced by a diverse group of compounds.


2020 ◽  
Vol 7 ◽  
Author(s):  
Zhen Dong ◽  
Shou-ye Xing ◽  
Ji-yu Zhang ◽  
Xu-zheng Zhou

To evaluate the safety of ivermectin microemulsion injection, 100 Wistar rats were injected intraperitoneally at 0.38 g/kg, 0.19 g/kg, and 0.1 g/kg for 14 days. The 14-day repeated toxicity test of ivermectin microemulsion injection was systematically evaluated by clinical observation, organ coefficient, hematological examination, clinical chemistry examination, and histopathological examination. The results showed that no rats died during the test. At the initial stage of treatment, the rats in the high dose group had mild clinical reaction, which disappeared after 4 days. Clinical chemistry showed that the high dose of ivermectin microemulsion could cause significant changes in ALT and LDH parameters in male rats; high and medium doses could increase the liver coefficients of male and female rats. The toxic target organ may be the liver as indicated by histopathological findings. No significant toxic injury was found in the heart, liver, spleen, lung, kidney, brain, ovary, and testes of all groups of rats. No drug-related toxic effects were found at low doses, and thus the NOVEL of ivermectin microemulsion injection was 0.19 g/kg.


2018 ◽  
Vol 2 ◽  
pp. 239784731877306 ◽  
Author(s):  
Torbjørn Rage Paulsen ◽  
Sebastian Stiller ◽  
Klaus Weber ◽  
Claudia Donath ◽  
Gudrun Schreiband ◽  
...  

To evaluate the safety of the synthetic capsaicin analogue phenylcapsaicin (PheCap; 7-phenylhept-6-yne-acid-hydroxy-3-mathoxylbenzylamide, CAS no 848127-67-3), a 90-day repeated dose oral gavage of 0, 30, 100 or 250 mg/kg body weight (bw)/day toxicity study with a 28-day recovery period was conducted using Wistar rats. Examinations of clinical signs, body and organ weight, haematology, urinalysis, clinical chemistry, food consumption and macroscopic, as well as histopathological tissue examinations were carried out for signs of toxicity. Degenerative, but reversible changes in the liver at 250 mg/kg bw/day, and local irritating effects in the stomach at 100 and 250 mg/kg bw/day were found. These findings were associated with test item-related clinical symptoms, that is, diarrhoea, salivation and moving of bedding material. PheCap did neither cause gene mutations by base pair changes or frame shifts in the genome of the tester stains Salmonella typhimurium TA 98, TA 100, TA 1535, TA 1537 or TA 102 nor induce structural and/or numerical chromosomal damage in human lymphocytes. Therefore, it can be concluded that PheCap is not genotoxic. The No Observed Adverse Effect Level (NOAEL) of PheCap for systemic toxicity is considered to be at 100 mg/kg bw/day which is based on degenerative changes in the liver. Due to irritating effects in the stomach, the NOAEL for local effects was established at 30 mg/kg bw/day.


Sign in / Sign up

Export Citation Format

Share Document