Tosyl chloride

Endpoint summary

Description of key information

Testing in OECD 422 for up to 51 days (in females) resulted to limited local effects in the stomach following treatment of a corrosive substance, which recovered during a 14-day recovery period at the lowest dose level of 150 mg/kgbw/day. No systemic toxicity was observed at this level. The hydrolysis product p-toluenesulphonic acid is the substance that will become systemically available.  A GLP guideline study with p-toluenesulphonic acid reported no adverse effects to male and female rats exposed orally for 28 days. The highest dose was 500 mg/kg bw/day. Evaluations from cross-reading involving longer duration studies of 90-days do not result to lower NOAELs. Based on this information it is justified to take 150 mg/kg bw as NOAEL for systemic toxicity.

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

repeated dose toxicity: oral, other

Remarks:

combined repeated dose and reproduction / developmental screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2003

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP study according to guideline. Although only summary available it has been peer internationally reviewed within OECD and assigned reliability 1.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

Deviations:

no

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

- male/female
- Age of animals at study: 9 weeks old for males and females
- Weight at study repeated dose toxicity: 325.8 - 363.1 g for males and 198.5 - 229.3 g for females
- Number of test animals: 60 animals for each sex

Route of administration:

oral: gavage

Vehicle:

not specified

Details on oral exposure:

According to the preliminary test (Report No. P104), dose level was set to 0, 150, 350 and 750 mg/kg/day.

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

Exposure period : 34, 36 - 45, and 51 days for male, copulated female and not copulated female animals, respectively.

Frequency of treatment:

Daily

Remarks:

Doses / Concentrations:
0, 150, 350 and 750 mg/kg/day
Basis:

No. of animals per sex per dose:

12 animals/sex/dose, plus 6 in 14-day recovery group/sex for control and high dose

Control animals:

yes, concurrent vehicle

Details on study design:

Including 14 day recovery groups for control and high dose

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily; mortality: twice/day
- Cage side observations checked in table [No.?] were included.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Weekly

BODY WEIGHT: Yes
- Time schedule for examinations: once a week and just before the necropsy, but in case of pregnant females, it was measured on the day 0, 7, 14, 20 of the gestation period, date of delivery, and 4 days of the lactation day.

FOOD CONSUMPTION:
- Food consumption: Yes: once a week except mating period

WATER CONSUMPTION: No

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes / No / No data
- Time schedule for collection of blood:
- Anaesthetic used for blood collection: Yes (identity) / No / No data
- Animals fasted: Yes / No / No data
- How many animals:
- Parameters checked in table [No.?] were examined.

HAEMATOLOGY and CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at moment of necropsy
- Animals fasted: Yes
- How many animals: randomly selected 5 male and female rats from each test group
- Parameters examined:
Haematocrit, hemoglobin concentration, erythrocyte count, total and different leucocyte count, platelet count, prothrombin time, and active partial thromboplastin time.
Biochemical test: sodium, potassium, chloride, glucose, total cholesterol, blood urea nitrogen, creatinine, total protein, albumin, alanine aminotransferase, aspartate aminotransferase, and total bilirubin.

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: before necropsy and during lactation for males and females, respectively
- Dose groups that were examined: 5 animals were randomly selected from each test group
- Battery of functions tested: Behaviour, grip strength, prayer reflex test and corneal reflex

Sacrifice and pathology:

GROSS PATHOLOGY: Yes

ORGAN WEIGHT: testes, epididymider (all males) liver, kidney, adrenals, thymus, spleen, brain and heart (5 male and female rats from each test group).

HISTOPATHOLOGY: Yes
22 tissues were fixed to perform histopathological evaluations including: testes, epididymides, ovaries, accessory sex organs for all animals, brain (including cerebrum, cerebellum and pons), spinal cord, stomach, small and large intestines (including Peyer’s patches), liver, kidneys, adrenals, spleen, heart, thymus, thyroid, trachea, lungs, uterus, urinary bladder, lymph nodes (cervical mesenteric), peripheral nerve (sciatic or tibial), and bone marrow.

Statistics:

Statistical decision tree, but in case of recovery group, either two-side Student’s t-test or two-side Aspin-Welch t-test was used. In case of categorical data, two-sided Fisher’s exact test was used.

Clinical signs:

effects observed, treatment-related

Mortality:

mortality observed, treatment-related

Body weight and weight changes:

effects observed, treatment-related

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Gross pathological findings:

not specified

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Details on results:

CLINICAL SIGNS AND MORTALITY
No mortality males; in females 350 mg/kg: 2/12 and at 750 mg/kg: 4/18
In the control groups, there were no specific clinical symptoms during test period.
150 mg: Intermittent (blood-like) salivation and staining around mouth (3/18 males, 6/18 females), and in females at delivery: difficult delivery, poor nursing, irregular respiration, uterus introsusception and piloerection.
350 mg: Intermittent (blood-like) salivation and staining around mouth were observed after day 15 and (blood-like) staining around nose (7/12 males, 4/12 females). Iintermittent soft stool and staining around anorectal region were observed for the most male animals and in 2 females. One female showed difficult delivery, lacrimation, and irregular respiration from day 4.
750 mg: soft stool and staining around anorectal region for most males and all females; and 5 cases of loss of hair around tail region were observed. Intermittent (blood-like) salivation and 9 cases of staining around mouth and 9 cases of (blood-like) staining around nose. Soft stool and staining around anorectal region for all animals; some cases of intermittent diarrhea were observed. Some animals with found dead and in dying condition had symptoms such as irregular respiration, crawing position, hypoactivity, and abdominal swelling.
In the 750 mg/kg/day recovery group, salivation, staining around mouth, soft stool and staining around anorectal region were not observed during the recovery period.

BODY WEIGHT AND WEIGHT GAIN
From start of dosing BW gain at 750 mg/kg group a bit lower resulting to a lower BW of 8% in males and 5.5% in females compared to controls during first week of recovery which partly recovered during the second week of the recovery period.

FOOD CONSUMPTION:
Only during the first week food consumption some somewhat lower in the 750 mg group.

HAEMATOLOGY
No major changes were seen compared to control, although the reported that dose related decrease in RBC and HCT and an increase in platelet counts were observed in males (see table)

CLINICAL CHEMISTRY
In males and females BUN is decreased compared to control at 750 mg/kg but not in the recovery groups. Total cholesterol was decreased in the recovery groups. In females chloride is decreased at 750 mg/kg (See table)

NEUROBEHAVIOUR
No significant effects were found.

ORGAN WEIGHTS
No effects were seen in sex-organ weights. Weight of the spleen was increased in treatment groups compared to controls for both males and females, although in females not relative weight. No differences in spleen weights were seen in recovery groups. In males the absolute, but not the relative, weight of the heart was decreased in the 750 mg/kg group. In the female recovery group the weights for adrenal and the brain were increased. (See table)

GROSS PATHOLOGY
No information provided

HISTOPATHOLOGY: NON-NEOPLASTIC
See table.

Key result

Dose descriptor:

LOAEL

Effect level:

150 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Based on salivation and effects of irritation in nongranular stomach in males and females, and difficulty delivery and poor nursing in females.

Critical effects observed:

not specified

Hematology of males (group mean)
Group	WBC (103/mm3)	RBC (106/mm3)	HGB (g/dl)	HCT (%)	PLT (103/mm3)
C	11.2	8	15.4	43.2	910.6
T1	13.6	7.7	15.3	41.7	999.2
T2	13.7	7.3	14.7	40.3	1,092
T3	13.1	7.3	14.7	41	1,100
Recovery (group mean)
C	13.2	7.8	15.1	41.4	917
T3	13.7	7.8	15.4	42.9	915.2

 

 

Clinical Biochemistry of males (group mean)
Treatment	TP	ALB	AST	ALT	BUN	CREA	TCHO	GLU	Na	K	Cl
(mg/kg/day)	g/dL	g/dL	IU/L	IU/L	mg/dL	mg/dL	mg/dL	mg/dL	mmol/L	mmol/L	mmol/L
0	6	2.3	148.3	46.5	11.3	0.6	98.8	69	147.2	4.6	104
150	5.8	2.2	132.5	28.6	10.7	0.5	114.2	64.4	143.8	4.6	102
350	5.8	2.3	122.8	31.3	9.6	0.5	102.8	66	145.4	4.9	102.4
750	5.6	2.2	127.2	41.3	7.8	0.5	102.8	58.6	145.6	4.4	102.6
Recovery
0	5.8	2.3	103.9	32.7	11.7	0.6	116	67.2	143.2	4.7	104.8
750	5	1.9	93	31.4	12.8	0.5	105.2	46.4	128.8	4.1	94.2
Clinical Biochemistry of females (group mean)
0	5	2	102.5	59.9	14.1	0.7	105.6	85	140.4	4.1	100.4
150	5.1	2.1	101.6	54.1	13.6	0.7	112.2	70.6	144	4.5	102.6
350	5.4	2.2	94.3	61.1	13.3	0.7	102.8	73	139.4	4.6	100.8
750	5.2	2.1	107.2	63.4	11.4	0.6	121.4	79.6	142.2	4.9	99.6
Recovery
0	6.7	3.1	125.4	38.8	12.1	0.6	140.6	96.8	145	4.3	107.2
750	6.6	2.9	103.9	30.6	15.3	0.6	128	86.6	144.4	4.2	103.6

 

Dose (mg/kg)	0	150	350	750	satellite
					0	750
Absolute (sex) organ weight of males
Testes(g)	3.04	3.285	3.332	3.203	3.337	3.208
Epididymis(g)	1.258	1.29	1.37	1.3	1.388	1.335
Liver (g)	10.698	11.142	10.698	10.01	11.139	10.736
Thymus(g)	0.355	0.307	0.356	0.32	0.31	0.297
Kidneys(g)	2.364	2.272	2.502	2.385	2.397	2.474
Adrenals(g)	0.061	0.064	0.062	0.068	0.053	0.055
Spleen(g)	0.632	0.725	0.783	0.794	0.844	0.716
Brain(g)	1.985	1.947	2.022	1.91	2.064	2.018
Heart(g)	1.325	1.244	1.282	1.182	1.411	1.382
Absolute organ weight of females
Liver (g)	6.947	6.886	7.298	7.431	6.855	6.621
Kidneys(g)	1.46	1.451	1.433	1.5	1.523	1.509
Adrenals(g)	0.071	0.073	0.073	0.072	0.057	0.066
Thymus(g)	0.106	0.14	0.161	0.096	0.298	0.291
Brain(g)	1.884	1.885	1.883	1.855	1.742	1.87
Spleen(g)	0.397	0.419	0.494	0.476	0.477	0.472
Heart(g)	0.818	0.809	0.853	0.767	0.876	0.829

 

Histopathological findings of males (Group)
Dose level (mg/kg/day)	0	150	350	700
No. of animals examined	5	5	5	5
Observation(s)	No. of animals observed
No significant findings	2	4	4	3
Liver: focal necrosis
Minimal	0	0	0	1
Nonglandular stomach: epithelial proliferation and vacuolation
Minimal	0	2	0	0
Moderate	0	3	0	0
Marked	0	0	5	5
Nonglandular stomach: hyperkeratosis
Minimal	0	3	0	0
Slight	0	2	5	5
Nonglandular stomach: submucosal edema
Minimal	0	0	0	1
Slight	0	0	4	4
Moderate	0	3	1	0
Nonglandular stomach: inflammation
Slight	0	3	5	5
No. of animals examined (reproductive organs)	12	12	12	12
Observation(s)	No. of animals observed
No significant findings	10	12	12	10
Testes: atrophy and degeneration of seminiferous tubules
Minimal	0	0	0	1
Moderate	2	0	0	0
Marked	0	0	0	1
Epididymides: oligospermia
Minimal	1	0	0	0
Marked	1	0	0	1

 

Histopathological findings of females (Group)
Dose level (mg/kg/day)	0	150	350	700
No. of animals examined	5	0	0	0
Observation(s)	No. of animals observed
No significant findings	5	1	0	0
Liver: focal necrosis
Minimal	0	0	0	0
Heart: inflammatorycell foci
Minimal	1	0	0	0
Nonglandular stomach: epithelial proliferation and vacuolation
Minimal	0	1	1	1
Slight	0	2	3	3
Marked	0	0	1	1
Nonglandular stomach: hyperkeratosis
Minimal	0	1	3	1
Slight	0	0	2	3
Moderate	0	0	0	1
Nonglandular stomach: submucosal edema
Slight	0	1	1	1
Nonglandular stomach: inflammation
Minimal	0	1	2	3
No. of animals examined (reproductive organs)	12	12	10	9
Observation(s)	No. of animals observed
No significant findings	12	12	10	9

Conclusions:

LOAEL = 150 mg/kg bw based on salivation and effects of irritation in nongranular stomach in males and females at this dose level.

Executive summary:

Tosyl chloride was dose by gavage to groups of 12 Sprague-Dawley rats/sex/dose level at levels of 0, 150, 350 and 750 mg/kg/day for 35 days and 36 - 51 days for male and female rats, respectively. A separate group of 6 animals/sex were added for a 14-day recovery group to the control and the high dose groups. Some clinical signs were observed at the dose level of 150 mg/kg/day for males animals such as intermittent (blood-like) salivation and staining around mouth; and for female animals such as intermittent (blood-like) salivation, staining around mouth, difficulty delivery, poor nursing, and irregular respiration. Moreover, at the dose level of 150 mg/kg/day, the digestive system and nonglanular stomach were also affected.

No effects were observed in the animals of the recovery groups.

Consequently the reporting concludes of a NOAEL < 150 mg/kg bw/day.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LOAEL

150 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

More and longer studies are available on the hydrolysis product of Tosyl chloride, that all indicate a lower toxicity level than suggested with this selected key study.

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Tosyl chloride has been evaluated in a Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screening Test according to OECD 422 and in compliance to GLP. The results are reported in the OECD SIDS dossier on 4-methylbenzenesulfonyl chloride. Although only summary available it has been internationally peer reviewed within OECD and was assigned reliability 1.

Tosyl chloride was dosed by gavage to groups of 12 Sprague-Dawley rats/sex/dose level at levels of 0, 150, 350 and 750 mg/kg/day for 35 days and 36 - 51 days for male and female rats, respectively. A separate group of 6 animals/sex were added for a 14-day recovery group to the control and the high dose groups.

Results: No mortality males; in females 350 mg/kg: 2/12 and at 750 mg/kg: 4/18

Some clinical signs were observed at the dose level of 150 mg/kg/day in both male and females such as intermittent (blood-like) salivation and staining around mouth. Effects were more severe at 350 mg/kg and at 750 mg/kg reported clinical signs were soft stool and staining around anorectal region for most males and all females; and 5 cases of loss of hair around tail region were observed. Intermittent (blood-like) salivation and 9 cases of staining around mouth and 9 cases of (blood-like) staining around nose. Soft stool and staining around anorectal region for all animals; some cases of intermittent diarrhea were observed. A decreased BW gain was observed in the 750 mg group resulting to a lower BW that was maximal 8% lower in males and 5.5% in females compared to controls. Food consumption was a bit lower during the first week in the 750 mg group. Histopathology showed dose related effects of epithelial proliferation and inflammation of the forestomach already visible in animals treated at 150 mg.

There were no further major changes observed in other parameters (haematology, biochemistry, neurobehavioral functions, organ weights)

In the 750 mg/kg/day recovery group, salivation, staining around mouth, soft stool and staining around anorectal region were not observed during the recovery period.

Consequently the reporting concludes of a NOAEL < 150 mg/kg bw/day.

 

 

Tosyl chloride rapidly hydrolyses into Toluene-4-sulphonic acid and HCl, both strong acids. Systemic exposures will therefore actually be on Toluene-4-sulphonic acid. Consequently, cross-reading from Toluene-4-sulphonic acid for longer term repeated dose studies can be applied. The following data is available on Toluene-4-sulphonic acid (p-toluenesulphonic acid, CAS 104-15-4):

 

Toluene-4-sulphonic acid was evaluated for repeated dose toxicity in an 28-day study according to OECD 407 and in compliance to GLP. Groups of 10 male and female Wistar rats for dosed 4, 20, 100 and 500 mg/kg bw/d by gavage. The selection of dose levels was based on a preliminary study in which a single dose of 1250 mg.kg bw of the test substance resulted in 40% mortality of female rats.

Results: In the highest dose group (500 mg/kg bw/day) urine was acidic in both males and females. Also at the highest dose, some of the males had higher salivation production which was considered an irritation reaction. Neither the acidic urine nor salivation were considered significant adverse effects (i.e., toxicologically relevant) in this study. The therefore was established at NOAEL 500 mg/kg bw/d.

Further data based on read-across is included to view a derived NOAEL for a related substance. Hydrotropes are the salt form of the sulphonic acids. The studies with the salts (hydrotropes) provide valid read-across for the acids. The specific cation is not expected to have an appreciable effect on fate, ecotoxicity or mammalian toxicity and therefore the dataset for the entire hydrotropes category can be applied broadly. 

The aromatic sulphonic acids are almost completely ionized in watery environments even at low pH. The salts of these acids are the hydrotropes (or “sulphonates”) which include ammonium, calcium, potassium and sodium cations. In principle the salts get dissociated when in contact with water, so forming back to the acids. Because of their close chemical similarities and because much of the production of the aromatic sulphonic acids goes to manufacturing the salts, the extensive dataset for the hydrotropes can also be used as a source of read-across for endpoints in an aromatic sulphonic acid dossier. This is particularly relevant for studies that are conducted in water (e.g., ecotoxicity and biodegradation) as well as for mammalian toxicity studies where the relatively high acidity of the acid form has an immediate and harsh local effect, whereas the salt form provides an indication of potential systemic toxicity beyond the site of application or initial contact.

 

There are a total of 6 oral repeated dose studies for the hydrotrope sodium xylene sulphonate (CAS No. 1300-72-7). The key study is a 90-day oral study, conducted in 1968, is generally comparable to the OECD 408 guideline study. In that study, the highest dose for female rats - 4092 mg active ingredient (a.i.) per kilogram body weight - resulted in a loss in relative weight of the spleen. The 2nd highest dose for females - 763 mg a.i. per kilogram body weight - had no measureable adverse effects and therefore establishes the repeat dose oral NOAEL for the test substance. The highest oral dose for male rats - 3534 mg a.i. per kilogram body weight - had no measurable adverse effects. No adverse effects were reported in a 90 day mouse study with the same substance.

 

 

Evaluation: As result of the rapid hydrolysis into Toluene-4-sulphonic acid and HCl, both strong acids, the most important and dose limiting effect is local irritation in the stomach, resulting a LOAEL of 150 mg/kg bw in a subacute study. At this level however, no systemic effects occurred. This is supported by information on the hydrolysis product Toluene-4-sulphonic, where a 28-day study resulted to a NOAEL of 500 mg/kg bw. Evaluation from cross-reading involving longer duration studies of 90-days (but also 2 year studies) show a comparable low toxicity and high NOAEL.

Therefore, it seems reasonable to take 150 mg/kg bw/day as a NOAEL for systemic toxicity.

Justification for selection of repeated dose toxicity via oral route - systemic effects endpoint:

Most relevant study resulting to the lowest NOAEL based on local effects.

Justification for selection of repeated dose toxicity inhalation - systemic effects endpoint:

Exposures by inhalation are unlikely in view of the low vp of 0.13 Pa at 20°C, its low dustiness (the respirable fraction (≤ 4 µm) of the hygroscopic, crystalline solid is below 0,04%) and low likelihood of exposures by aerosols with uses limited to chemical intermediate in industrial settings. Furthermore Tosyl chloride readily hydrolyses to toluene sulfonic acid and HCL which are both corrosive acids. Inhalation of dust particles will therefore lead to respiratory irritation/corrosion rather than expected to result in systemic toxicity.

Justification for selection of repeated dose toxicity inhalation - local effects endpoint:

Exposures by inhalation are unlikely in view of the low vp of 0.13 Pa at 20°C, its low dustiness (the respirable fraction (≤ 4 µm) of the hygroscopic, crystalline solid is below 0,04%) and low likelihood of exposures by aerosols with uses limited to chemical intermediate in industrial settings. Additionally it would technically be difficult to perform inhalation studies with Tosyl chloride dust in view of its hygroscopic properties.

Justification for selection of repeated dose toxicity dermal - systemic effects endpoint:

Tosyl chloride is used as a chemical intermediate in industrial or professional setting, where due to its corrosive/irritant and sensitising properties adequate protection is applied. Exposures are consequently limited.

Justification for selection of repeated dose toxicity dermal - local effects endpoint:

Tosyl chloride is used as a chemical intermediate in industrial or professional setting, where due to its corrosive/irritant and sensitising properties adequate protection is applied. Exposures are consequently limited.

Repeated dose toxicity: via oral route - systemic effects (target organ) digestive: stomach

Justification for classification or non-classification

Classification for STOT is relevant where significant toxic effects are seen from repeated dose studies.The available OECD 422 study indicated that no systemic toxicity was seen at levels that do lead to overt corrosive effects on the stomach. The dose level of 350 mg/kg bwclearly resulted to local effects in the stomach, but no further systemic effects were observed. Considering the rapid hydrolysis to Toluene-4-sulphonic acid, available information on this substance is highly relevant for Tosyl chloride. The NOAEL of 500 mg/kg for Toluene-4-sulphonic acid from a 28-day study also indicated that no classification for STOT is required.