Reaction mass of Benzene sulfonic acid, hexadecyl(sulfophenoxy)-,disodium salt and Benzene sulfonic acid, - oxibis[hexadecyl]-, disodium salt

Repeated dose toxicity: oral

Administrative data

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1976

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted prior to GLP and test guidelines, but the report contains sufficient data for interpretation of study results.

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1976

Report date:

1976

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Male and female Sprague-Dawley rats were maintained for 90-91 days on diets containing sifficient DOWFAX surfactant XD-8390 to provide dose levels of 0, 50, 100, 200 or 600 mg/kg/day to assess the toxicological effects that might be associated with daily ingestion of this material by rats for that length of time. Determinations of body weight and food consumption were made throughout the study and the animals were examined frequently for overt signs of toxicity. Hematological and clinical chemistry parameters were monitored. Gross and microscopic pathological examinations were conducted at the termination of the study. The weights of the brain, heart, liver, kidney and testes were recorded and organ/body weight ratios were calculated.

GLP compliance:

no

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

405-430-6

EC Name:

-

Cas Number:

65143-89-7

Molecular formula:

UVCB

IUPAC Name:

Reaction mass of Benzene sulfonic acid, hexadecyl(sulfophenoxy)-,disodium salt and Benzene sulfonic acid, - oxibis[hexadecyl]-, disodium salt

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

Dowfax surfactant XD-8390
Reference: Lot # MM10154
Source: Functional Resins, The Dow Chemical Company
Purity: Sample met sales specifications for the material

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

Sprague-Dawley, Spartan substrain, specific pathogen free-derived rats, 6-7 weeks of age were placed randomly in individual suspended wire-bottom cages. Food and water were available free choice throughout the study.

Administration / exposure

Route of administration:

oral: feed

Vehicle:

other: none, undiluted, dried material

Details on oral exposure:

Attempts to incorporate the formulated 36% solution itself into ground laboratory chow were unsatisfactory. Therefore, the solution of XD-8390 was dried to a fine powder for incorporation in the diets. Since the dried powder was hygroscopic, it was kept in air-tight containers until it was used in the study.

Analytical verification of doses or concentrations:

no

Details on analytical verification of doses or concentrations:

Not applicable

Duration of treatment / exposure:

90 days for males and 91 days for females

Frequency of treatment:

Daily

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 50, 100, 200 or 600 mg/kg/day
Basis:
nominal in diet

No. of animals per sex per dose:

15

Control animals:

yes, plain diet

Details on study design:

Sprague-Dawley, Spartan substrain, specific pathogen free-derived rats, 6-7 weeks of age were placed randomly in individual suspended wire-bottom cages. Groups of rats, each consisting of 15 males and 15 females, were fed diets containing sufficient XD-8390 to provide dose levels of 0, 50, 100, 200 or 600 milligrams of powdered XD-8390/ kg/day. Food and water were available free choice throughout the study. A 5% premix of XD-8390 in ground laboratory chow (Ralston-Purina Company) was used to prepare the test diets, with the final concentration of test material adjusted weekly according to the mean food consumption and body weight of each group of rats to maintain the designated dose levels on a mg/kg/day basis.

Positive control:

None

Examinations

Observations and examinations performed and frequency:

Body weights and food consumption were recorded weekly throughout the study.The rats were observed at least twice weekly for alterations in demeanor or other signs of toxicity. Hematological evaluations and urinalyses were performed on 10 rats/sex of the control and 600 mg/kg/day groups during the final week of the study. The hematological parameters evaluated included packed cell volume (PCV), red blood cell count (RBC), hemoglobin concentration (Hgb), white blood cell count (WBC), and differential leucocyte count. The urinalyses included determination of pH, specific gravity, sugar, protein, ketones, occult blood and bilirubin. Clinical chemistry determinations were conducted at the termination of the study on serum samples from 10 rats/sex of the controls and each treatment level. These determinations included urea nitrogen concentration, alkaline phosphatase activity and serum glutamic pyruvic transaminase activity.

Sacrifice and pathology:

At the termination of the study (90 days for males, 91 days for females), the rats were starved overnight, weighed, killed by decapitation and a gross
pathological examination was performed. The weights of the brain, heart, liver, kidney and testes were recorded.

Tissues from heart, liver, kidney, thyroid, parathyroid, esophagus, lung, adrenal gland, spleen, pancreas, stomach, small intestine, trachea, gonads, uterus, urinary bladder, accessory sex glands, skeletal muscle, peripheral nerve, spinal cord, brain, pituitary gland, thymus, aorta, mesenteric and mediastinal lymph nodes were collected and preserved in buffered 10% formalin. Routine histologic procedures were used to prepare hematoxylin and
eosin stained sections of these tissues. Histopathologic examinations were conducted by a veterinary pathologist on all tissues from 10 rats/sex of the control and high dose level groups. Similar sections of liver and kidney were also prepared from 10 rats/sex of the group receiving 200 mg/kg/day. Sections of liver from 4-5 rats/sex of the high dose level and control groups were cut on a freezing microtome and were stained with red oil-0 to evaluate the lipid content by light microscopy.

Other examinations:

At necropsy, the eyes were examined by pressing a microscope slide gently on the cornea while viewing with the aide of a fluorescent lamp. The eyes from 10 rats/sex/dose level were preserved in Zenker's fixative. Eyes from the remaining rats were preserved in buffered 10% formalin. The eyes from 10 rats/sex of the control and high dose level groups were processed and examined histologically.

Statistics:

Analyses of body weights, food consumption, hematological and clinical chemistry parameters, organ weights and organ to body weight ratios were made by an analysis of variance and the treatment means were compared with control values by Dunnett's test . The level of significance chosen for all cases was p<0.05.

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

no effects observed

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

effects observed, treatment-related

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

effects observed, treatment-related

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Histopathological findings: neoplastic:

no effects observed

Details on results:

Appearance and Demeanor.
No alterations in appearance or demeanor or significant clinical signs were observed in any of the male or female rats at any dose level of XD-8390 or in the control groups.

Body Weights and Food Consumption.
No significant effect on body weights was observed in either sex at any dose level of test material. In all cases, the weight gained by test animals was comparable to that of control rats. Any alterations in food consumption occurred on a sporadic basis and were not considered to be related to ingestion of XD-8390 in the diet.

Hematology.
The mean hematologic values for rats of the high dose level and control groups on day 84 of the study were summarized. No parameters were significantly affected by ingestion of the test material in the diet.Since there was no effect on hematologic measures at the high dose level of test material i n either sex, these parameters were not measured on animals at the lower dose levels of XD-8390.

Clinical Chemistry.
The blood urea nitrogen concentration and alkaline phosphatase activity were not significantly different from that of the control group at any dose level of XD-8390 among either the males or the females. There was a marginal but statistically significant increase in serum glutamic pyruvic transaminase activity at all dose levels of test material in the male but not female rats. This apparent increase in the SGPT activity in male rats was not considered an indication of hepatotoxicity for a number of reasons - the response was not related to the dose level of test material in the diet, there was no histologic evidence of liver damage among the rats at any dose level, alkaline phosphatase activity was not increased in the same rats and the increase occurred only in the males, not among the females. The increase in SGPT activity could have reflected an effect on organ(s) other than the liver, most likely the kidney in these rats. This enzyme has been found in a number of tissues in other species of animals (Cornelius, et al., 1959) and elevated
blood levels of the enzyme may reflect an effect on these organs.

To further assess t h e meaning of this observation in rats, additional groups of rats (4/sex in each group) were given XD-8390 orally by gavage at dose levels of 0, 100, 300 or 1000 mg/kg for 2 consecutive days. Twenty-four hours after the second dose, the rats were killed and blood was collected for determination of SGPT and AP activitites. This schedule is optimal for detection of an elevation of these enzymes since they reach the highest serum levels during acute liver involvement. . The SGPT activity w a s significantly elevated among male and female rats dosed with 1000 mg XD-8390/kg but not 300 or 100 mg/kg. AP activity was not elevated in any test group of either sex. The liver of all rats dosed with XD-8390 was similar in gross appearance to that of the control rats. Thus, under test conditions optimal for detecting an effect indicative of hepatotoxicity, SGPT activity was moderately elevated in a dose-related manner in rats of both sexes. Thus, in the present 90-day study, it was not possible to unquestionably determine the source of the enzyme or if the elevated activity was in fact related to ingestion of XD-8390. In a concurrent 90-day dietary toxicity study of XD-8390 in beagle dogs, there was no effect observed on SGPT activity.

Urinalyses.
Among the male
rats, the specific gravity of urine was slightly higher than that of control rats at dose levels of 100 mg/kg/day and higher; the increase was statistically significant at the high dose level, 600 mg/kg/day. Among the female rats , the specific gravity of urine was slightly higher than that of control
rats at all dose levels of test material with the difference being statistically significant only at the lowest dose level, 50 mg/kg/day. No other differences were observed between any treatment group and the corresponding control group for any of the urinalysis parameters evaluated.

Pathology.
Both the absolute and the relative weights of the kidneys were statistically significantly increased among male and female rats at the high dose level, 600 mg/kg/day. Among the females, the absolute weight of the kidneys was also significantly higher than that of the control rats at 200 mg/kg/day. The weights of the other organs were not different from control values at any dose level of test material and the weights of the kidneys were comparable to control values at dose levels of 100 mg/kg/day and lower.

Discernible observations considered relatable to ingestion of XD-8390 in the diet were limited to the kidneys of rats at the two higher dose levels, 600 and 200 mg/kg/day. In the group of female rats at 600 mg/kg/day, gross examination revealed a slight degree of swelling of the kidneys; at 200
mg/kg/day, gross examination suggested an equivocal degree of swelling of the kidneys. These observations were substantiated by the statistically significant increase in the weights of the kidneys at these dose levels. The only observation made upon microscopic examination of the tissues was also in the kidneys - very slight dilatation of renal tubules among some of the female rats at the highest dose level of test material, 600 mg/kg/day. Gross and microscopic examination of other organs revealed no alterations that could be associated with ingestion of any of the dose levels of XD-
8390 used in this study.

The possibility that the sodium content of XD-8390 may have contributed to the effect observed in the kidneys was considered and subsequently discounted. The average sodium content of the basal ration used in this study is 0.45%. The maximum contribution of sodium to the diet of these animals from the added XD-8390 was in the range of 0.02-0.03%. An increment of this small extent is very likely less than the between-lot variation in sodium content of the ration and is easily within the limits of physiological adaptation by the body.

Effect levels

1

Dose descriptor:

NOAEL

Effect level:

100 mg/kg bw/day (nominal)

Sex:

female

Basis for effect level:

other: Based on morphological manifestations in the kidneys at the two highest doses.

2

Dose descriptor:

NOAEL

Effect level:

200 mg/kg bw/day (nominal)

Sex:

male

Basis for effect level:

other: Based on morphological manifestations in the kidneys at the highest dose.

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

None

Applicant's summary and conclusion

Conclusions:

Morphological manifestations which could be associated with ingestion of the test material were observed only at the two higher dose levels, 200 and 600 mg/kg/day and were limited to effects on the kidneys. The weights of the kidneys were significantly increased at the two higher dose levels among the female rats and at the highest dose level among the male rats. The kidneys of these groups of rats appeared swollen at the time of necropsy and among the females, a slight dilation in the renal tubules was observed microscopically at the highest dose level. The kidney morphology and function was not different from that of control rats at the two lower dose levels of the test material. The SGPT activity was increased at all dose levels in the male rats in the absence of any histological or other biochemical evidence of liver damage. Except for these changes no alterations in other parameters were observed at any dose level. Based on these findings the NOAEL in rats was 100 and 200 mg/kg/day for female and male rats, respectively.

Executive summary:

Male and female Sprague-Dawley rats were maintained for 90-91 days on diets containing sufficient DOWFAX surfactant XD-8390 to provide dose levels of 0, 50, 100, 200 or 600 mg/kg/day to assess the toxicological effects that might be associated with daily ingestion of this material by rats for that length of time. Determinations of body weight and food consumption were made throughout the study and the animals were examined frequently for overt signs of toxicity. Hematological and clinical chemistry parameters were monitored. Gross and microscopic pathological examinations were conducted at the termination of the study. The weights of the brain, heart, liver, kidney and testes were recorded and organ/body weight ratios were calculated.

Morphological manifestations which could be associated with ingestion of the test material were observed only at the two higher dose levels, 200 and 600 mg/kg/day and were limited to effects on the kidneys. The weights of the kidneys were significantly increased at the two higher dose levels among the female rats and at the highest dose level among the male rats. The kidneys of these groups of rats appeared swollen at the time of necropsy and among the females, a slight dilation in the renal tubules was observed microscopically at the highest dose level. The kidney morphology and function was not different from that of control rats at the two lower dose levels of the test material. The SGPT activity was increased at all dose levels in the male rats in the absence of any histological or other biochemical evidence of liver damage. Except for these changes no alterations in other parameters were observed at any dose level. Based on these findings the NOAEL in rats was 100 and 200 mg/kg/day for female and male rats, respectively.