Benzenesulfonic acid, C10-13-alkyl derivs., sodium salts

Repeated dose toxicity: dermal

Administrative data

Endpoint:

sub-chronic toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1978

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Reference

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1978

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline followed

Principles of method if other than guideline:

The purpose of this study is to determine the sub-acute toxicity of C10-13 sodium linear alkyl benzene sulfonate (LAS-Na) in CRJ-SD rats. LAS-Na was orally administered at 0 (distilled water), 125, 250 and 500 mg/kg bw to male and females rats for 29 and 30 days, respectively. General symptoms of toxicity and the body weights were recorded daily while the food consumption was measured twice a week. Urinalysis was also performed during the study. At the end of study, blood was collected for estimation of haematological and clinical chemistry parameters. After collection of blood samples, the animals were humanely euthanized, gross necropsy was performed and organs weights were determined.

GLP compliance:

no

Remarks:

(pre-dates GLP)

Limit test:

no

Species:

rat

Strain:

other: CRJ-SD rats

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories Japan, Inc.
- Age at study initiation: 5 weeks
- Weight at study initiation: Not reported
- Fasting period before study: Not reported
- Housing: 3 male and 4 female animals per cage.
- Diet: Solid feed (CE-2, CLEA Japan, Inc.); ad libitum
- Water: Tap water; ad libitum
- Acclimation period: After 1 week pre-housing, the animals were used in the experiment.

ENVIRONMENTAL CONDITIONS
- Temperature: 23 ± 2°C
- Humidity: 55 ± 5%
- Air changes: Not reported
- Photoperiod: Not reported

EXPERIMENTAL START DATE: Not reported

Route of administration:

oral: gavage

Details on route of administration:

The test substance was administered orally through a metallic gastric sonde.

Vehicle:

other: Distilled water

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS: The test substance was suspended in distilled water prior to dosing.

- DOSE VOLUME: 5 mL/kg bw

- Concentration in vehicle: 0, 250, 500, and 1000 mg/mL respectively for administration of doses of 0, 125, 250 and 500 mg/kg bw.

Analytical verification of doses or concentrations:

no

Details on analytical verification of doses or concentrations:

29 days for males and 30 days for females

Duration of treatment / exposure:

29 days for males and 30 days for females

Frequency of treatment:

Once daily

Dose / conc.:

125 mg/kg bw/day (actual dose received)

Remarks:

In distilled water (corresponding to 250 mg/mL)

Dose / conc.:

250 mg/kg bw/day (actual dose received)

Remarks:

In distilled water (corresponding to 500 mg/mL)

Dose / conc.:

500 mg/kg bw/day (actual dose received)

Remarks:

In distilled water (corresponding to 1000 mg/mL)

No. of animals per sex per dose:

Test group: 12 animals/sex/dose group
Control group: 15 male/group and 16 female/group

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: The dose levels for this study were selected based on the results of acute toxicity study conducted with LAS-Na in rats. 1/3 of the LD50 levels of LAS-Na, i.e. 500 mg/kg bw, was selected as the highest dose. The other two doses were set at common ratios of 2, whereby the medium and low doses were 250 (1/6 LD50) and 125 (1/12 LD50) mg/kg bw, respectively.

Positive control:

No

Observations and examinations performed and frequency:

CLINICAL OBSERVATIONS: Yes
- Time schedule: Daily

BODY WEIGHT: Yes
- Time schedule for examinations: Daily

FOOD CONSUMPTION AND COMPOUND INTAKE:
- Food consumption: Yes
- Time schedule for examinations: Twice/week

FOOD EFFICIENCY: Yes

WATER CONSUMPTION AND COMPOUND INTAKE: No

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: After 1 month, blood was collected was collected from the carotid artery using a cannula.
- Anesthetic used for blood collection: Yes, light ether anesthesia was used.
- Animals fasted: Not reported
- How many animals: All surviving animals
- Parameters: Haemoglobin, haematocrit, red and white blood cell count were measured using an auto-analyzer SMA-4A.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: After 1 month, blood was collected from each animal and centrifuged (at 3000 rpm for 15 minutes) to obtain the serum samples for analysis.
- Animals fasted: No
- How many animals: All surviving animals
- Parameters: s-GOT, s-GPT, alkaline phosphatase, total protein, albumin, glucose, cholesterol, bilirubin, creatinine, urea nitrogen, inorganic phosphates and ions (Na+, K+, Ca2+, Mg2+ and Cl-)

URINALYSIS: Yes
- Time schedule: Not reported
- Metabolism cages used for collection of urine: No
- Animals fasted: No
- How many animals: All surviving animals
- Parameters: pH, proteins, sugar, ketone bodies and occult blood

NEUROBEHAVIOURAL EXAMINATION: No

IMMUNOLOGY: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes

ORGAN WEIGHTS: The wet weight of liver, kidneys, spleen, adrenal glands, lungs, heart, thymus, reproductive organ, pituitary and the brain were measured. Based on this, the relative weights were calculated.

HISTOPATHOLOGY: No

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

At 500 mg/kg bw, animals exhibited the action of wetting the area around the mouth and nose, and rubbing it against the cage. Many animals exhibited diarrhea from the start of dosing as well as a suppressed state, several hours after dosing. Soft stool was observed in some animals dosed at 125 and 250 mg/kg bw, however, the animals showed recovery at low and mid doses.

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Male animals of all dose groups and female animals of high dose group (i.e. 500 mg/kg bw) exhibit body weight suppression.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Animals showed a dose dependent decline in the feed consumption.

Food efficiency:

effects observed, treatment-related

Description (incidence and severity):

Decreased feed efficacy was observed for male animals at 500 mg/kg bw.

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

Effects at 125 mg/kg/bw: Decreased total proteins (only females), albumin (only females), Ca2+ levels (only males), and increased cholesterol (only males)
Effects at 250 mg/kg bw: Decreased s-GPT (both males and females), total proteins (only females), albumin (only females), Na+ (only males), K+ (only males), Ca2+ (both males and females), and Mg2+ (only males)
Effects at 500 mg/kg bw: Decreased s-GOT (only females), total proteins (only females), albumin (only females), glucose (only females), Ca2+ (both males and females), and increased alkaline phosphatase (only males) and urea nitrogen (only females).

Urinalysis findings:

no effects observed

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

The relative liver weight of female animals was significantly increased at 500 mg/kg bw (p<0.01). Apart from this, increase in relative weight of adrenal glands (p<0.05 for right side; p<0.01 for left side), testes (p<0.05) and brain (p<0.05) was also observed in male animals at 500 mg/kg bw. Decrease in the relative weight of liver (only females; at 125 mg/kg bw, p<0.05), right side kidney (only females; at 250 and 500 mg/kg bw, p<0.05), spleen (only males; at 500 mg/kg bw, p<0.05), heart (both males and females at 500 mg/kg bw, p<0.01; males at 250 mg/kg bw, p<0.05; females at 125 mg/kg bw, p<0.05) and thymus (only females; at 500 mg/kg bw, p<0.01) was also observed. Although, some significant effects were observed at the low and mid dose yet they were not dose-dependent.

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

At 500 mg/kg bw, the animals showed hypertrophy in the stomach wall of the proventriculus, as if the process of inflammation and recovery had repeated over and over. Therefore, formation of new capillaries was observed on the peritoneal side. There were no additional changes relative to the control group although, events of hydronephrosis, bleeding plaques on the thymus and pneumonia were observed including the control group.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Other effects:

not examined

Dose descriptor:

NOAEL

Effect level:

125 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

organ weights and organ / body weight ratios

Remarks on result:

other: Based on reduced body weight and changes in organ weight (without histopathological correlation), clinical chemistry. The LOAEL was 250 mg/kg bw/day.

Critical effects observed:

not specified

Table 1: Effect of LAS on average feed efficiency of rats after 1 month (po) exposure (Ito et al., 1978)

Sex	Doses	2 weeks			4 weeks
		Total intake (g)	Net gain (g)	Efficacy (%)	Total intake (g)	Net gain (g)	Efficacy (%)
Males	0	346.5	108.8	31.4	747.6	199.1	25.6
	125	322.7	97.5	30.2	692.3	183.2	25.4
	250	316.4	92.8	29.4	690.2	177.5	24.6
	500	284.2	76.5	27	633.5	152.4	22.7
Females	0	274.4	60.4	21.9	573.3	114.9	18.4
	125	236.6	53.7	22.6	513.1	105.4	19.5
	250	246.4	55.3	21.9	534.8	110.9	19.4
	500	231.7	49.6	21.4	486.5	97.8	18

Table 2: Effect of LAS on haematological parameters of rats after 1 month (po) exposure (Ito et al., 1978)

Sex	Doses	RBC (10^6/mm^3)	Hb (g/dL)	Ht (%)	WBC (10^3/mm^3)
Males	0	7.5 ± 0.11	16.5 ± 0.17	48.8 ± 0.63	16.5 ± 1.04
	125	7.4 ± 0.08	16.0 ± 0.13	47.4 ± 0.49	17.4 ± 1.12
	250	7.4 ± 0.17	15.9 ± 0.36	47.4 ± 1.13	17.8 ± 1.30
	500	7.5 ± 0.07	16.0 ± 0.12	48.1 ± 0.34	18.8 ± 1.41
Females	0	6.6 ± 0.15	15.2 ± 0.18	44.0 ± 0.65	12.1 ± 0.49
	125	6.6 ± 0.15	15.2 ± 0.15	44.4 ± 0.56	12.0 ± 0.87
	250	6.6 ± 0.11	15.2 ± 0.13	44.5 ± 0.51	13.5 ± 0.91
	500	6.8 ± 0.06	15.2 ± 0.10	44.2 ± 0.41	14.5 ± 1.31

Mean ± SE

* Significantly different from control (p<0.05)

** Significantly different from control (p<0.01)

Table 3a: Effect of LAS on biochemical parameters of rats after 1 month (po) exposure (Ito et al., 1978)

Sex	Dose (mg/kg)	sGOT	sGPT	ALP	TP	Alb	Glu	Chol
		mu/mL	mu/mL	mu/mL	mg%	mg%	mg%	mg%
Males	0	137.0± 5.4	44.5 ± 1.6	294.8 ± 11.6	5.4 ± 0.08	3.3 ± 0.05	228.7 ± 5.8	55.4 ± 1.27
	125	134.3 ± 8.4	39.5 ± 1.9	280.2 ± 17.5	5.1 ± 0.14	3.2 ± 0.08	228.9 ± 9.0	60.8* ± 2.38
	250	133.3 ± 7.3	39.3 ± 1.5*	311.8 ± 26.6	5.1 ± 0.27	3.1 ± 0.16	225.3 ± 11.5	54.5 ± 2.48
	500	145.4 ± 7.3	45.0 ± 2.1	374.0* ± 30.0	5.2 ± 0.07	3.3 ± 0.04	218.3 ± 3.5	53.4 ± 1.25
Females	0	130.3 ± 6.5	48.5 ± 1.1	184.9 ± 8.2	6.1 ± 0.08	3.8 ± 0.05	224.1 ± 5.7	67.7 ± 2.24
	125	141.0 ± 7.3	44.4 ± 1.1	205.2 ± 10.0	5.8** ± 0.7	3.7* ± 0.05	231.7 ± 8.4	63.9 ± 1.89
	250	134.5 ± 7.1	39.9 ± 0.8*	182.5 ± 11.5	5.7* ± 0.16	3.5** ± 0.09	216.2 ± 7.1	64.9 ± 2.81
	500	162.5* ± 10.7	44.1 ± 2.0	222.7 ± 17.9	5.7** ± 0.08	3.6** ± 0.05	207.8* ± 5.5	62.3 ± 2.30

Mean ± SE

* Significantly different from control (p<0.05)

** Significantly different from control (p<0.01)

Table 3b: Effect of LAS on biochemical parameters of rats after 1 month (po) exposure (Ito et al., 1978)

Sex	Dose (mg/kg)	T-Bili	Creat	BUN	InP	Na	K	Ca	Mg	Cl
		mg%	mg%	mg%	mg%	meg/L	meg/L	mg/dL	mg/dL	meg/L
Males	0	0.9 ± 0.03	0.5 ± 0.01	17.4 ± 0.99	6.8 ± 0.14	147.6 ± 1.7	5.0 ± 0.10	5.1 ± 0.07	2.5 ± 0.04	102.5 ± 0.62
	125	0.8 ± 0.04	0.5 ± 0.02	17.1 ± 1.32	6.8 ± 0.16	142.3 ± 2.0	4.8 ± 0.14	4.6* ± 0.14	2.5 ± 0.10	103.7 ± 0.65
	250	0.8 ± 0.04	0.4 ±0.03	17.0 ± 0.09	6.4 ± 0.26	135.8* ± 3.1	4.5** ± 0.11	4.6** ± 0.15	2.2** ± 0.05	104.6 ± 0.77
	500	0.9 ± 0.02	0.5 ± 0.02	19.3 ± 1.17	6.8 ± 0.10	141.5 ± 2.9	5.0 ± 0.17	4.8* ± 0.12	2.4 ± 0.06	104.4 ± 1.22
Females	0	0.9 ± 0.09	0.5 ± 0.02	17.9 ± 0.82	6.2 ± 0.14	143 ± 1.3	4.5 ± 0.09	5.2 ± 0.08	2.5 ± 0.07	105.4 ± 0.43
	125	0.8 ± 0.02	0.5 ± 0.01	17.9 ± 1.51	6.3 ± 0.23	143.4 ± 1.9	4.5 ± 0.08	5.0 ± 0.11	2.5 ± 0.07	106.8 ± 0.66
	250	0.8 ± 0.05	0.5 ± 0.01	18.7 ± 0.99	6.3 ± 0.22	145.3 ± 1.5	4.4 ± 0.15	4.9* ± 0.06	2.5 ± 0.06	106.8 ± 0.54
	500	0.9 ± 0.06	0.6 ± 0.02	24.0* ± 1.41	6.1 ± 0.21	142.6 ± 1.2	4.5 ± 0.08	4.9** ± 0.08	2.4 ± 50.0	106.6 ± 0.42

Mean ± SE

* Significantly different from control (p<0.05)

** Significantly different from control (p<0.01)

Table 4a: Effect of LAS on organ weight of rats after 1 month (po) exposure (Ito et al., 1978)

Sex

Dose (mg/kg)

Body weight (g)

Liver

Kidney

Spleen

Adrenal gland

Right

Left

Right

Left

wt (g)

%

wt (g)

%

wt (g)

%

wt (g)

%

wt (mg)

%

wt (mg)

%

Males

0

370.7± 6.0

14.60 ± 0.39

3.94 ± 0.08

1.38 ± 0.03

0.37 ± 0.01

1.38 ± 0.04

0.37 ± 0.01

0.70 ± 0.03

0.19 ± 0.01

25.6 ± 1.2

6.91 ± 0.32

25.8 ± 1.0

6.97 ± 0.26

125

355.1 ± 7.5

13.72±0.33

3.87 ± 0.06

1.36 ± 0.04

0.39 ± 0.01

1.33 ± 0.04

0.38 ± 0.01

0.68 ± 0.03

0.19 ± 0.01

24.4 ± 1.8

6.88 ± 0.48

25.3 ± 1.1

7.16 ± 0.37

250

349.8* ± 7.6

13.65 ± 0.42

3.90 ± 0.09

1.31 ± 0.03

0.38 ± 0.01

1.29 ± 0.03

0.37 ± 0.01

0.62 ± 0.03

0.18 ± 0.01

24.7 ± 1.4

7.06 ± 0.34

25.4 ± 1.5

7.24 ±0.35

500

324.4** ±9.0

13.37 ± 0.57

4.11 ± 0.11

1.21** ± 0.04

0.37 ± 0.01

1.20** ± 0.04

0.37 ± 0.01

0.53** ± 0.02

0.16* ± 0.01

26.2 ± 1.0

8.15* ± 0.40

28.5* ± 0.6

8.88** ± 0.36

Females

0

262.6± 8.0

10.84 ± 0.51

4.11 ± 0.08

1.09 ± 0.04

0.41 ± 0.01

1.08 ± 0.05

0.41 ± 0.2

0.55 ± 0.02

0.21 ± 0.01

34.0 ± 1.2

13.00 ± 0.38

35.8 ± 1.3

13.63 ± 0.30

125

258.0 ± 3.5

10.03 ± 0.22

3.89* ± 0.05

0.98* ± 0.03

0.38* ± 0.01

0.95* ± 0.02

0.37* ± 0.01

0.57 ± 0.02

0.22 ± 0.01

31.7 ± 1.1

12.27 ± 0.37

32.1 ± 1.5

12.43 ± 0.54

250

261.5 ± 4.5

10.56 ± 0.30

4.04 ± 0.08

1.00 ± 0.03

0.38* ± 0.01

0.96 ± 0.03

0.37* ± 0.01

0.56 ± 0.03

0.22 ± 0.01

31.0 ± 1.8

11.94 ± 0.84

33.4 ± 1.7

12.83 ± 0.76

500

249.7* ± 3.1

11.58 ± 0.21

4.64** ± 0.08

0.97** ± 0.02

0.39* ± 0.01

0.95* ± 0.02

0.38 ± 0.01

0.51 ± 0.01

0.21 ± 0.01

32.0 ± 1.9

12.79 ± 0.69

32.3 ± 2.0

12.89 ± 0.75

Mean ± SE

* Significantly different from control (p<0.05)

** Significantly different from control (p<0.01)

%: X10^-3

Table 4b: Effect of LAS on organ weights of rats after 1 month (po) exposure (Ito et al., 1978)

Sex

Dose (mg/kg)

Lung

Heart

Thymus

Testis/Ovarium

Pituitary

Brain

Right

Left

wt (g)

%

wt (g)

%

wt (g)

%

wt (mg)

%

wt (mg)

%

wt (mg)

%

wt (g)

%

Males

0

1.23± 0.02

0.33± 0.01

1.27 ± 0.05

0.34 ± 0.01

0.52 ± 0.02

0.14 ± 0.01

1.53 ± 0.03

0.41 ± 0.01

1.51 ± 0.03

0.41 ± 0.01

10.4 ± 0.4

2.81 ± 0.11

1.84 ± 0.03

0.50 ± 0.01

125

1.23 ± 0.03

0.35 ± 0.01

1.18 ± 0.03

0.33 ± 0.01

0.56 ± 0.05

0.16 ± 0.01

1.48 ± 0.03

0.42 ± 0.01

1.51 ± 0.03

0.43 ± 0.01

11.1 ± 1.1

3.14 ± 0.32

1.83 ± 0.03

0.52 ± 0.01

250

1.20 ± 0.03

0.35 ± 0.01

1.41 ± 0.03

0.33* ± 0.01

0.48 ± 0.02

0.14 ± 0.01

1.49 ± 0.04

0.43 ± 0.01

1.49 ± 0.03

0.43 ± 0.01

10.9 ± 0.7

3.10 ± 0.16

1.82 ± 0.02

0.52 ± 0.01

500

1.13* ± 0.03

0.35 ± 0.01

0.97** ± 0.03

0.30** ± 0.01

0.41** ± 0.03

0.13 ± 0.01

1.49 ± 0.04

0.46* ± 0.02

1.49 ± 0.04

0.46* ± 0.02

9.6 ± 0.4

2.99 ± 0.16

1.77* ± 0.02

0.55* ± 0.02

Females

0

1.07 ± 0.03

0.41 ± 0.01

0.96 ± 0.03

0.37 ± 0.01

0.59 ± 0.02

0.23 ± 0.01

44.8 ± 2.9

17.04 ± 0.95

47.8 ± 3.5

18.13 ± 1.07

11.8 ± 0.4

4.53 ± 0.18

1.80 ± 0.02

0.69 ± 0.02

125

1.10 ± 0.05

0.43 ± 0.02

0.88** ± 0.01

0.34* ± 0.01

0.54 ± 0.02

0.21 ± 0.01

46.2 ± 2.5

17.94 ± 1.04

43.7 ± 1.8

16.93 ± 0.64

12.3 ± 0.8

4.79 ± 0.30

1.78 ± 0.02

0.69 ± 0.01

250

1.11 ± 0.03

0.42 ± 0.01

0.92 ± 0.02

0.35 ± 0.01

0.55 ± 0.03

0.21 ± 0.01

46.5 ± 2.8

17.73 ± 0.94

47.6 ± 2.8

18.12 ± 0.91

11.8 ± 0.8

4.53 ± 0.30

1.76 ± 0.02

0.68 ± 0.01

500

1.01 ± 0.02

0.41 ± 0.01

0.79** ± 0.03

0.32** ±0.01

0.44** ± 0.04

0.18** ± 0.02

46.3 ± 3.5

18.51 ± 1.29

46.2 ± 2.7

18.44 ± 0.97

11.8 ± 0.9

4.71 ± 0.34

1.75* ± 0.01

0.70 ± 0.01

Mean ± SE

* Significantly different from control (p<0.05)

** Significantly different from control (p<0.01)

%: X10^-3

Conclusions:

Oral administration of C10-13 sodium linear alkylbenzene sulphonate (LAS-Na) to CRJ-SD rats at 0, 125, 250 and 500 mg/kg bw for 1 month resulted in a NOAEL of 250 mg/kg bw, based on reduced body weight, changes in organ weight (without histopathological correlation) and clinical chemistry at the mid and high doses. The LOAEL was 500 mg/kg bw.

Executive summary:

A short-term repeated dose toxicity study was conducted with C10-13 LAS, sodium salt in CRJ-SD rats. The test substance was administered via oral gavage to groups of male and female rats for 28 days at dose levels of 0, 125, 250 and 500 mg/kg/day. Clinical signs of toxicity and the body weights were recorded daily while the food consumption was measured twice a week. Urinalysis was also performed during the study. At the end of study, blood was collected for estimation of haematological and clinical chemistry parameters, following which the animals were humanely euthanized, gross necropsy was performed, the organs weights were determined and histopathological examination of the major organs were performed. Body weight gain was suppressed, some serum biochemical measures were different from the controls, and some organ weights were either decreased (spleen, heart, thymus) or increased (liver) at the high dose. No mortalities or histopathological abnormalities were observed. No adverse effects were up to 125 mg/kg bw/day mg/kg/day. Under the study conditions, the systemic toxicity NOAEL was determined to be 125 mg/kg/day based on reduced body weight, changes in organ weight (without histopathological correlation) and clinical chemistry at the mid and high doses (Ito, 1978a). 

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1978

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The purpose of this study is to determine the chronic toxicity (transdermal) of C10 - C13 linear alkylbenzene sulfonic acid magnesium salt (LAS-Mg) in CRJ-SD rats. Male and female rats were transdermally administered with 0 (water), 3% PEG, 0.5, 1.0 and 5.0% of test substance dissolved in 3% polyethyleneglycol (PEG, MW: 200) for 26 weeks. General symptoms and body weight of animals were recorded on a daily-basis and food intake were recorded weekly. Urinalysis and haematological examinations were performed in week 5 and 13 of the study. At the end of study, urinalysis, haematological and serum biochemistry were also done. All the surviving animals were humanely euthanized after 26 weeks and organs (liver, kidneys, spleen, adrenal glands, lungs, heart, thymus, reproductive organ, pituitary, brain and thyroid) were collected for recording absolute and relative organ weights. All the collected organs were examined under the microscope for histopthalogical changes.

GLP compliance:

no

Remarks:

(pre-dates GLP)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

C10-13 magnesium linear alkylbenzene sulphonate

Cas Number:

Not available

Molecular formula:

Not applicable as the substance is UVCB

IUPAC Name:

C10-13 magnesium linear alkylbenzene sulphonate

Test material form:

not specified

Test animals

Species:

rat

Strain:

other: CRJ-SD

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Male and female rats were obtained from Charles River Laboratories Japan, Inc.
- Age at study initiation: Approximately 4 weeks
- Weight at study initiation: Not reported
- Fasting period before study: Not reported
- Housing: Animals were housed in cages with 2 animals/cage.
- Diet: Solid feed (CE-2, CLEA Japan, Inc.); ad libitum
- Water: Tap water; ad libitum
- Acclimation period: 1 week

ENVIRONMENTAL CONDITIONS
- Temperature: 22 ± 1°C
- Humidity: 55 ± 5%
- Air changes: Not reported
- Photoperiod: Not reported

IN LIFE DATES: Not reported

Administration / exposure

Type of coverage:

not specified

Vehicle:

other: 3% polyethyleneglycol (PEG, MW: 200)

Details on exposure:

TEST SITE
- Area of exposure: Shaved backs of animals
- % coverage: 3 x 3 cm2 area in the middle of the backside
- Type of wrap if used: Not reported
- Time intervals for shavings or clippings: Weekly

REMOVAL OF TEST SUBSTANCE
- Washing: Not reported
- Time after start of exposure: Not reported

TEST MATERIAL
- Amount applied: 0.1 mL
- Concentration: 0.5, 1.0 and 5.0% of C10-C13 LAS-Mg in 3% polyethyleneglycol

VEHICLE
- 3% polyethyleneglycol (PEG, MW: 200)

USE OF RESTRAINERS FOR PREVENTING INGESTION: No

Analytical verification of doses or concentrations:

no

Duration of treatment / exposure:

26 weeks

Frequency of treatment:

Once daily for 26 weeks (excluding Sundays)

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

0.5 other: %

Doses / concentrations 2

Dose / conc.:

1 other: %

Doses / concentrations 3

Dose / conc.:

5 other: %

No. of animals per sex per dose:

20 animals/sex/dose group

Control animals:

other: 2 Control animals groups were applied with either PEG or distilled water.

Details on study design:

- Dose selection rationale: Not reported
- Rationale for animal assignment: Not reported
- Rationale for selecting satellite groups: No satellite groups were used in the study

Positive control:

Not included

Examinations

Observations and examinations performed and frequency:

CLINICAL OBSERVATIONS: Yes
- Time schedule: All animals were observed daily for general symptoms.

DERMAL IRRITAION: Yes

BODY WEIGHT: Yes
- Time schedule for examinations: All animals were weighed daily.

FOOD CONSUMPTION AND COMPOUND INTAKE: Yes
- Time schedule: Amount of food intake was measured once per week.

FOOD EFFICIENCY: Yes

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: During weeks 5, 11 and 26
- Anaesthetic used for blood collection: Yes. The animals were anesthetized with sodium pentobarbital
- Animals fasted: Not reported
- How many animals: During weeks 5 and 11, blood was collected from 10 animals/sex from PEG group, control group and 5.0% group and in week 26, blood was collected from all animals.
- Parameters checked: Red blood cell count, white blood cell count, haemoglobin level and haematocrit level were measured, and white blood cell fractions were calculated by Giemsa-staining the blood smear samples.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: At end of study i.e. 26 weeks
- Animals fasted: Not reported
- How many animals: All animals
- Parameters checked: s-GOT, s-GPT, alkaline phosphatase, total protein, albumin, glucose, cholesterol, bilirubin, creatinine, urea nitrogen, inorganic phosphates and Cl-, Na+, K+, Ca2+ and Mg2+

URINALYSIS: Yes
- Time schedule for collection of urine: During weeks 5, 11 and 26
- Metabolism cages used for collection of urine: No
- Animals fasted: Not reported
- How many animals: During weeks 5 and 11, urine was collected from 10 animals/sex from PEG group, control group and 5.0% group and in week 26, urine was collected from all animals.
- Method: Lab sticks, Urobilistix and iktstix method (Semi-quantitative investigation)
- Parameters: pH, protein, glucose, ketone bodies, occult blood, urobilinogen and bilirubin

NEUROBEHAVIOURAL EXAMINATION: No

IMMUNOLOGY: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
All animals were euthanized after blood sampling and organs were immediately collected.

TISSUE COLLECTED FOR ORGAN WEIGHTS AND HISTOPATHOLOGY: Liver, kidneys, spleen, adrenal glands, lungs, heart, thymus, reproductive organ, pituitary, brain and thyroid

HISTOPATHOLOGY: Above collected organs and stomach, duodenum, ileum, cecum, pancreas, bone marrow and skin were fixed in 10% formalin, embedded in paraffin and underwent H&E staining before being examined under the microscope

Results and discussion

Results of examinations

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

In half of the animals of highest tested dose, mild redness of test site was observed one week after starting to apply it, but this disappeared after one week with desquamation. This did not occur again thereafter. Among female animals, all animals in the 5.0% group and one animal from the 1.0% group developed mild redness after one month since the start of study, but these went away after one week. After two, three months, half the animals in the 5.0% group exhibited mild redness, and it was seen sporadically thereafter.

Mortality:

mortality observed, non-treatment-related

Description (incidence):

One male animal from the control group (Week 16) and one male animal from the 5.0% group (Week 23) died during the study, but the cause remains unknown after finding no abnormalities through the necropsies.

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

Male animals in the 0.5% group exhibited mild weight suppression from Week 11, but this had recovered by Week 16. At the end of the experiment, slight weight suppression was observed in male animals from the 0.5% group.

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

no effects observed

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, non-treatment-related

Description (incidence and severity):

5 weeks interim analysis: There were significant increase in segmented neutrophils and significant decrease in white blood cell count for male animals in PEG group and increase in hematocrit levels in male animals in 5.0% dose group
13 weeks interim analysis: level: Significant increase in red blood cells and hemoglobin levels were observed in males of 5.0% dose group and increased white blood cell count was also observed for male and female animals in the PEG and 5.0% groups. In white blood cell fractions, decrease in eosinophils was observed for female animals in the 5.0% group.
6 month analysis: Significant decrease in white blood cell count were observed for female animals in the 5.0% group, as well as for both male and female animals in the 1.0% group. Significant increase in lymphocytes for male animals in the PEG group and significant decrease in monocytes for male animals in the 5.0 and 0.5% groups were also observed.

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

PEG group: Significant decrease was observed in s-GOT levels for female animals and in sodium and s-GPT levels for all animals.
5.0% dose group: There was significant reduction in glucose in females, in calcium levels in males and sodium and s-GPT in all animals. Elevated levels of A/G ratio and cholesterol were also observed in females.
1.0% dose group: There is significant decrease in glucose in females and sodium levels in all animals and increase in urea nitrogen in females of this group.
0.5% dose group: There is significant decrease in sodium levels in all animals of this group and increase in urea nitrogen in females of this group.

Urinalysis findings:

no effects observed

Description (incidence and severity):

Similar levels of all tested parameters (protein, occult blood, Urobilinogen and pH) were observed in treated animals as compare to control animals in 13 as well as 26 weeks interim analysis.

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

There were decrease in actual and relative liver weights of 0.5% (low) dose group. No dose dependency was observed for this effect.

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

- Liver stasis was observed for one male animal in the 1.0% group, while blood spots and fading colour were observed for another male animal in the same group. Furthermore, white serpentine bulges were observed for three male animals each in the 5.0 and 0.5% groups, as well as in four male animals in 1.0% group and one male animal in the 0.5% group.
- Kidney oedema was observed for one female each in the control and 0.5% groups.
- Yellow discoloration was observed in pancreas for one male animal in the control group.
- Lungs stasis was observed for one male animal in the 1.0% group.
- Heart hypertrophy was observed for one male animal in the 1.0% group.
- Blood spots in thymus were observed for two male animals each in the control, PEG and 1.0% groups, as well as in four male animals in the 5.0 and 0.5% groups.
- Testicular atrophy was observed for one male in the 1.0% group, while ovarian oedema was observed for one female animal each in the control and 1.0% groups.
- Pituitary oedema was observed for one male animal in the 1.0% group.
- Stomach hematoma was observed in the cardia for one male animal in the 1.0% group, while an ulcer of 1 mm in diameter was observed for another male animal in the same group. Oedema was observed in the stomach for one male animal in the control group.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

effects observed, non-treatment-related

Description (incidence and severity):

Control group:
- Sinusoid bleeding was observed for one male and one female animal each, while focal necrosis was observed for one female animal.
- Renal tubular hyaline casts were observed for seven male animals and one female animal, while interstitial small round cell infiltration and renal tubular epithelial cell swelling were observed for two male and one female animals
- Fibrosis of islets of Langerhans observed for one male animal
- Interstitial myocarditis was observed for one male and one female animal each.
PEG group:
- Sinusoid bleeding was observed for three male animals, focal necrosis was observed in one male animal and Kupffer cell migration was observed for one female animal
- Renal tubular hyaline casts were observed for five male animals and one female animal, while interstitial small round cell infiltration and renal tubular epithelial cell swelling were observed for one male and one female animal each
- Adrenal gland: A hemorrhagic foci was observed in the stratum corneum for one male animal.
- Fibrosis of islets of Langerhans observed for one male animal.
5.0% dose group:
- Sinusoid bleeding was observed for five male animals, while focal necrosis was observed for two male animals. Kupffer cell migration was observed for one female animal.
- Renal tubular hyaline casts were observed for three male and female animals each, while interstitial small round cell infiltration was observed for two male animals. Renal tubular calcification was observed for another male animal.
- Fibrosis of islets of Langerhans observed for one male animal.
- Interstitial myocarditis was observed for two male animals and one female animal.
1.0% dose group:
- Sinusoid bleeding was observed for five male animals, while focal necrosis was observed for another male animal.
- Renal tubular hyaline casts were observed for five male and one female animals, interstitial small round cell infiltration was observed for one male and one female animal each, and renal tubular calcification was observed for two female animals
- Fibrosis of islets of Langerhans observed for four male animals
- Interstitial myocarditis was observed for one male animal.
- Decline in sperm production was observed for one male animal.
0.5% dose group:
- Sinusoid bleeding was observed for four male animals and one female animal, while large lipid droplets were observed for one male animal. Kupffer cell migration was observed for one female animal.
- Renal tubular hyaline casts were observed for five male and two female animals, interstitial small round cell infiltration was observed for one male animal and another male animal exhibited renal tubular epithelial cell swelling. Furthermore, renal tubular calcification was observed for one female animal.
- Fibrosis of islets of Langerhans observed for three male animals.
- Interstitial myocarditis was observed for three male animals.

Histopathological findings: neoplastic:

not examined

Effect levels

Key result

Dose descriptor:

NOAEL

Effect level:

2 500 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No significant adverse effect was seen at any dose level.

Remarks on result:

other: Based on no growth, functional and morphological abnormalities, other than the localized effects at any tested dose levels.

Target system / organ toxicity

Key result

Critical effects observed:

no

Applicant's summary and conclusion

Conclusions:

Transdermal administration of C10-13 magnesium linear alkylbenzene sulphonate (LAS-Mg; purity: 96.9%) to CRJ-SD rats at dose levels of 0 (water), 3% PEG, 0.5, 1.0 and 5.0% of test substance dissolved in 3% polyethyleneglycol (PEG, MW: 200) for 26 weeks revealed no observed adverse effect level (NOAEL) of 5.0%, based no toxicologically relevant changes at any dose level.

Executive summary:

A sub-chronic 26-week repeated dose toxicity study was conducted in male and female CRJ-SD rats to evaluate the effects of C10-13 LAS, magnesium salt. The test substance was applied daily on the shaved backs of animals at dose levels of 0, 0.5, 1.0 and 5.0% dissolved in 3% polyethylene glycol (PEG) for 26 weeks with 20 animals/sex/dose group. General symptoms and body weight of animals were recorded on a daily-basis and food intake were recorded weekly. Urinalysis and haematological examinations were performed on Weeks 5 and 13 and also at termination, along with clinical biochemical examination. All the surviving animals were humanely euthanized after 26 weeks and organs were collected for recording absolute and relative weights and histopathological observation. There was slight reduction of body weight in males at 0.5% at the end of the study. No toxicologically significant changes were observed in food consumption, urinalysis, haematological and serum biochemical findings. No changes were seen in the organ weights and gross pathology of the collected organs. Histopathological findings were non-specific and had no dose-dependency. Under the study conditions, the systemic toxicity NOAEL was established at 5.0% (equivalent to 2500 mg/kg bw/day), based no toxicologically relevant changes at any dose level (Ito, 1978d).