A study to determine the doses for a subsequent 2-year study was conducted, in which groups of 10 male and 10-female B6C3F1 mice were provided with tap-water containing phenol (No. 690) at a concentration of 0, 100, 300, 1000, 3000,.or 10 000 mg/L for 13 weeks. The concentrations were calculated (Food & Drug Administration, 1993) to provide average intakes of 0, 25, 75, 250, 750, and 2500 mg/kg bw per day. All the mice survived to the end of the study: The mean body-weight gain of animals at the highest dose was depressed; animals in this group rejected the treated water. Microscopic examination revealed no treatment-related differences between treated and control mice. The NOELwas 750 mg/kg bw per day (National Toxicology Program, 1980).
Groups of 10 male and 10 female Fischer 344/N rats were given resorcinol (No 712) at a dose 0, 32, 65, 130, 260, or 520 mg/kg bw per day by oral gavage for 13 weeks. Eight males and 10 females at the highest dose died within the first 4 weeks; the deaths of two males and four females in the group at 260 mg/kg by per day dose during the first week were attributed to accidental administration o 520 mg/kg bw per day. The final mean body weights of the treated animals were comparable to those of controls. At necropsy, statistically significant increases it the absolute and relative weights of the liver were reported for males receiving 130 or 260 mg/kg bw per day and females receiving 65, 130, or 260 mg/kg bw per day of resorcinol. Significantly increased absolute and relative adrenal gland weights were also reported in all surviving treated males. Haematology, clinical chemistry, and gross and microscopic examination revealed no findings related to treatment (National Toxicology Program, 1992b).
Williamson Synthesis Lab Report | Ether | Chemical …
Groups of five male and five female Fischer 344/N rats were given resorcinol (No. 712) at a dose of 0, 27.5, 55, 110, 220, or 450 mg/kg bw per day by oral gavage on 5 days/week for 17 days. Males at the two higher doses and females at the four higher doses showed clinical signs including hyperexcitability and tachypnoea lasting up to 2 h. None of the rats died. The final mean body weights of the treated animals were comparable to those of controls. Females at the highest dose had significantly decreased absolute and relative thymus weights, but no other significant changes in organ weights were reported. Microscopic examination of the tissues revealed no abnormalities attributable to treatment (National Toxicology Program, 1992b).
Williamson ether synthesis phenol - Universo Online
A 13-week study was conducted in which groups of 30 male and 30 female Sprague-Dawley rats were given -cresol at a dose of 0, 50, 175, or 600 mg/kg bw per day by oral gavage. At the end of the study, the mean body weights of males and females at the highest dose were significantly lower than those of controls. Females at the intermediate and high doses showed statistically significant reductions in erythrocyte count, haemoglobin, and haematocrit, but compensatory responses to the anaemic state were not observed. Females at the highest dose also had elevated liver transaminase activity, but this finding was attributed to large increases in 4/10 animals, including two with chronic hepatic inflammation. Statistically significant increases in serum cholesterol were reported in females at the highest dose and in total protein in males at the two higher doses. Necropsy revealed significantly increased relative kidney weights in males at the intermediate dose and in males and females at the highest dose. Significantly increased relative weights of the liver, heart, testis, and brain were noted in males at the highest dose, while females at the lowest dose showed significantly increased relative spleen weights. Gross examination showed no treatment-related lesions. Histological evaluation revealed a significantly increased incidence of chronic nephropathy in males at the lowest and highest doses. A significantly increased incidence of epithelial metaplasia of the trachea was observed in animals at the highest dose than in controls, but no other treatment-related histological findings were reported. The NOEL was 50 mg/kg bw per day (Environmental Protection Agency, 1988b).
Williamson ether synthesis phenol: ..
Groups of 20 Fischer 344 rats of each sex were fed diets containing -cresol or -cresol (60%/40%) at a concentration of 0, 1900, 3800, 7500, 15 000, or 30 000 mg/kg for 13 weeks, providing average intakes of 0, 130, 250, 500, 1000, and 2000 mg/kg bw per day. All rats lived to the end of the study except for one female receiving the highest dose of -cresol. At the end of the study, the body weights of males and females at the two higher doses of both substances were significantly lower than those of. controls, except for males given 15 000 mg/kg of diet of -cresol. The relative weights of the liver were increased in males and females at the three higher doses of both isomers. The relative weights of the kidney were increased in animals at the two higher doses of -cresol and in males at the three higher doses and females at the highest dose of -cresol. The relative weights of the testes were increased in males at the highest dose of -cresol and at the two higherdoses of -cresol. Substantially increased concentrations of serum bile salts were reported in male and female rats given either isomer, particularly at the two highest doses, throughout the study. Consistent decreases in the activity of 5'-nucleotidase in serum were seen in rats given -cresol. Mild uterine atrophy was observed at the two higher doses of -cresol. Minimal to mild hypocellularity of the bone marrow was reported in males. and females at the two higher doses of both isomers, except in males at 15 000 mg/kg of diet of -cresol. All animals receiving -cresol showed hyperplasia of the olfactory and respiratory epithelium. Both isomers lengthened the estrus cycle of females treated at 7500 or 30 000 mg/kg of diet. The NOEL for both -cresol and cresol was 250 mg/kg bw per day (National Toxicology Program, 1992a).