1-(3-sulphonatopropyl)pyridinium

Endpoint summary

Description of key information

No mortality and clinical signs were detected in treated animals. Body weight, food consumption, haematology and blood chemistry parameters were comparable to controls. Behavioural parameters, functional performance and sensor reactivity were not affected. There were no treatment-related effects on mating, fertility and gestation lenghts for treated animals. No clinically observable signs of toxicity were detected for offspring from all treatment groups. Litters size, sex ratio, body weight development and surface righting reflex were not affected. No findings at necropsy were detected in adults and offspring. NOAEL of 1000 mg/kg bw, the highest dose level tested, was established for systemic toxicity and for reproductive performance. 

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: oral

Remarks:

combined repeated dose and reproduction / developmental screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013-03-05 to 2013-10-18

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline 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 (incl. QA statement)

Remarks:

The Department of Health of the Government of the United Kingdom

Limit test:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Strain: Han™:RccHan™:WIST.
- Source: Harlan Laboratories U.K. Ltd., Blackthorn, Bicester, Oxon, UK.
- Age at study initiation: 12 weeks.
- Weight at study initiation: 295 to 356 g (males), 188 to 217 g (females).
- Fasting period before study: no.
- Housing: Initially, all animals were housed in groups of four in solid floor polypropylene cages with stainless steel mesh lids and softwood flake bedding (Datesand Ltd., Cheshire, UK). During the pairing phase, animals were transferred to polypropylene grid floor cages suspended over trays lined with absorbent paper on a one male: one female basis within each dose group. Following evidence of successful mating, the males were returned to their original cages. Mated females were housed individually during gestation and lactation in solid floor polypropylene cages with stainless steel mesh lids and softwood flakes.
The animals were housed in a single air-conditioned room within the testing facility.
- Diet (e.g. ad libitum): ad libitum (Rodent 2018C Teklad Global Certified Diet, Harlan Laboratories U.K. Ltd., Oxon, UK).
- Water (e.g. ad libitum): ad libitum.
- Acclimation period: 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 ± 2
- Humidity (%): 55 ± 15
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 2013-04-10 To: 2013-06-05

Route of administration:

oral: gavage

Vehicle:

water

Remarks:

distilled

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
For the purpose of this study the test item was prepared at the appropriate concentrations as a suspension in Distilled water. The stability and homogeneity of the test item formulations were determined by Harlan Laboratories Ltd., Shardlow, UK, Analytical Services. Results show the formulations to be stable for at least twenty two days. Formulations were therefore prepared fortnightly and stored at approximately 4 °C in the dark.

VEHICLE
- Concentration in vehicle: 0, 20, 60 and 200 mg/mL for dose levels of 0, 100, 300 and 1000 mg/kg bw, respectively.
- Amount of vehicle (if gavage): 5 mL/kg bw. The volume of test and control item administered to each animal was based on the most recent scheduled body weight and was adjusted at weekly intervals.
- Lot/batch no. (if required):
- Purity: distilled water

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Samples of the test item formulation were taken and analysed for concentration of 1-(3- sulphonatopropyl)pyridinium at Harlan Laboratories Ltd., Shardlow, UK, Analytical Services. The methods used for analysis of formulations was HPLC/UV. The results indicate that the prepared formulations were within ± 6% of the nominal concentration.

Duration of treatment / exposure:

up to 8 weeks ((including a two week pre-pairing phase, pairing, gestation and early lactation for females).

Frequency of treatment:

once daily

Remarks:

Doses / Concentrations:
0, 100, 300 and 1000 mg/kg bw
Basis:
actual ingested

No. of animals per sex per dose:

12

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:
The dose levels were chosen based on the results of previous toxicity work (Harlan Laboratories Ltd., Project Number 41300261).
- Rationale for animal assignment: The animals were randomly allocated to treatment groups using a stratified body weight randomisation procedure and the group mean body weights were then determined to ensure similarity between the treatment groups. The cage distribution within the holding rack was also randomised.

Chronological Sequence of Study
i. Groups of twelve male and twelve female animals were treated daily at the appropriate
dose level throughout the study (except for females during parturition where applicable).
The first day of dosing was designated as Day 1 of the study.
ii. Prior to the start of treatment and once weekly thereafter, all animals were observed for
signs of functional/behavioural toxicity.
iii. On Day 15, animals were paired on a 1 male: 1 female basis within each dose group for a
maximum of fourteen days.
iv. Following evidence of mating (designated as Day 0 post coitum) the males were returned
to their original cages and females were transferred to individual cages.
v. On completion of the pairing phase (during Week 6), five selected males per dose group
were evaluated for functional/sensory responses to various stimuli.
vi. Pregnant females were allowed to give birth and maintain their offspring until Day 5 post
partum. Litter size, offspring weight and sex, surface righting and clinical signs were
also recorded during this period.
vii. At Day 4 post partum, five selected females per dose group were evaluated for
functional/sensory responses to various stimuli.
viii. Blood samples were taken from five males from each dose group for haematological and
blood chemical assessments on Day 42. The male dose groups were killed and examined
macroscopically on Day 43.
ix. Blood samples were taken from five randomly selected females from each dose group for
haematological and blood chemical assessment on Day 4 post partum. At Day 5 post
partum, all females and surviving offspring were killed and examined macroscopically.
Any female which did not show positive evidence of mating or produce a pregnancy was
also killed and examined macroscopically.

Positive control:

None.

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: All animals were examined for overt signs of toxicity, ill-health and behavioural change immediately before dosing, soon after dosing, and one hour and five hours after dosing during the working week. Animals were observed immediately before dosing, soon after dosing and
one hour after dosing at weekends and public holidays (except for females during parturition where applicable). All observations were recorded.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Prior to the start of treatment and at weekly intervals thereafter, all animals were observed for signs of functional/behavioural toxicity. Detailed individual clinical observations were performed for each animal using a purpose built arena. The following parameters were observed: Gait, Hyper/Hypothermia, Tremors, Skin colour, Twitches, Respiration, Convulsions, Palpebral closure, Bizarre/Abnormal/Stereotypic behaviour, Urination, Salivation Defecation, Pilo-erection, Transfer arousal, Exophthalmia, Tail elevation, Lachrymation.

BODY WEIGHT: Yes
- Time schedule for examinations: Individual body weights were recorded on Day 1 (prior to dosing) and then weekly for males until termination and weekly for females until mating was evident. Body weights were then recorded for females on Days 0, 7, 14 and 20 post coitum, and on Days 1 and 4 post partum. Body weights were also recorded at terminal kill.

FOOD CONSUMPTION AND COMPOUND INTAKE:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
During the pre-pairing period, weekly food consumption was recorded for each cage of adults. This was continued for males after the mating phase. For females showing evidence of mating, food consumption was recorded for the periods covering post coitum Days 0-7, 7-14 and 14-20.
For females with live litters, food consumption was recorded on Days 1 and 4 post partum.

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: Yes
Food efficiency (the ratio of body weight change/dietary intake) was calculated retrospectively for males throughout the study period (with the exception of the mating phase) and for females during the pre-pairing phase. Due to offspring growth and milk production, food efficiency could not be accurately calculated for females during gestation and lactation.

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Yes
Water intake was observed daily by visual inspection of water bottles for any overt changes.

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: prior to termination (Day 42 for males and Day 4 post partum for females).
- Anaesthetic used for blood collection: Yes (identity) / No / No data
- Animals fasted: No
- How many animals: five males and five females selected from each test and control group
- Parameters checked in table [No.1] were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: prior to termination (Day 42 for males and Day 4 post partum for females).
- Animals fasted: No
- How many animals: five males and five females selected from each test and control group.
- Parameters checked in table [No.1] were examined.

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: prior to termination
- Dose groups that were examined: Functional performance tests were also performed on five selected males and females from each dose level, prior to termination, together with an assessment of sensory reactivity to various stimuli.
- Battery of functions tested: sensory activity / grip strength / motor activity

Motor Activity:
Purpose-built 44 infra-red beam automated activity monitors were used to assess motor activity. Animals were randomly allocated to the activity monitors. The tests were performed at approximately the same time on each occasion (at least two hours after dosing), under similar laboratory conditions. The evaluation period was thirty minutes for each animal. The percentage of time each animal was active and mobile was recorded for the overall thirty minute period and also during the final 20% of the period (considered to be the asymptotic period, Reiter and Macphail, 1979).

Forelimb/Hindlimb Grip Strength:
An automated meter was used. Each animal was allowed to grip the proximal metal bar of the meter with its forepaws. The animal was pulled by the base of the tail until its grip was broken. The animal was drawn along the trough of the meter by the tail until its hind paws gripped the distal metal bar. The animal was pulled by the base of the tail until its grip was broken. A record of the force required to break the grip for each animal was made. Three consecutive trials were performed for each animal. The assessment was developed from the method employed by Meyer et al (1979).

Sensor reactivity:
Each animal was individually assessed for sensory reactivity to auditory, visual and proprioceptive stimuli. The following parameters were observed: Grasp response, Vocalisation, Toe pinch, Tail pinch, Finger approach, Touch escape, Pupil reflex, Blink reflex, Startle reflex.

OTHER:
Reproductive Performance (see section 7.8.1.)

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
Adult males were killed by intravenous overdose of sodium pentobarbitone followed by exsanguination on Day 43. Adult females were killed by intravenous overdose of sodium pentobarbitone followed by exsanguination on Day 5 post partum. Surviving offspring were terminated via intracardiac overdose of sodium pentobarbitone. Any females which failed to achieve pregnancy or produce a litter were killed on or after Day 25 post coitum. Any female which failed to mate was terminated on Day 57.

The following organs were dissected free from fat and weighed before fixation from five selected males and five selected females from each dose group: Adrenals, Brain, Epididymides, Heart, Kidneys, Liver, Ovaries, Pituitary (post fixation), Prostate, Seminal vesicles, Spleen, Testes, Thymus, Thyroid (weighed post-fixation with Parathyroid), Uterus (weighed with Cervix). The following tissues were weighed from all remaining animals: Epididymides, Ovaries, Pituitary (post fixation), Prostate, Seminal vesicles, Testes, Uterus (weighed with Cervix).

HISTOPATHOLOGY: Yes (see table 2)
Samples of the tissues mentioned in table 2 were removed from five selected males and five selected females from each dose group and preserved in buffered 10% formalin.
The following tissues were preserved from all remaining animals: Coagulating gland, Epididymides, Gross lesions, Mammary gland, Ovaries, Pituitary, Prostate, Seminal vesicles, Testes, Uterus/Cervix, Vagina.

Other examinations:

For all females, the uterus was examined for signs of implantation and the number of uterine implantations in each horn was recorded. This procedure was enhanced; as necessary, by staining the uteri with a 0.5% ammonium polysulphide solution (Salewski 1964). The corpora lutea were also counted.
All adult animals and offspring, including those dying during the study, were subjected to a full external and internal examination, and any macroscopic abnormalities were recorded.

Statistics:

See "Any other information on materials and methods incl.tables".

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:

no effects observed

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

no effects observed

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Details on results:

CLINICAL SIGNS AND MORTALITY
There were no treatment-related deaths. One female treated with 100 mg/kg bw/day died during the bleeding procedure on Day 4 post partum. This death was considered procedure related and therefore is of no toxicological significance.

There were no toxicologically significant clinical signs detected in treated animals. One male treated with 300 mg/kg bw/day had generalised scab formation between Days 19 and 23. Observations of this nature are commonly observed in group housed animals and is considered not to be of toxicological significance.

BODY WEIGHT AND WEIGHT GAIN
There were no toxicologically significant effects detected in body weight development. Males treated with 1000 and 300 mg/kg bw/day showed a statistically significant increase in body weight gain during Weeks 2 and 4 (p<0.05). Males treated with 100 mg/kg bw/day also showed a statistically significant increase in body weight gain during Week 4 (p<0.05). An increase in body weight gain is considered not to represent an adverse effect of treatment therefore the intergroup differences are of no toxicological importance.

FOOD CONSUMPTION AND FOOD EFFICIENCY
No adverse effect on food consumption or food efficiency was detected in treated animals when compared to control animals.

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study)
Daily visual inspection of water bottles did not reveal any significant intergroup differences.

HAEMATOLOGY
No toxicologically significant effects were detected in the haematological parameters examined.
Males from all treatment groups showed a statistically significant increase in neutrophil count when compared to controls. The majority of individual values were within normal ranges for rats of the strain and age used, and in the absence of true dose related response the intergroup differences were considered not to be of toxicological importance.
Males treated with 1000 mg/kg bw/day also showed a statistically significant increase in total leucocyte count. All of the individual values were within normal range for rats of the strain and age used, therefore the intergroup difference was considered not to be of toxicological importance.

CLINICAL CHEMISTRY
No toxicologically significant effects were detected in the blood chemical parameters examined. Males from all treatment groups showed a statistically significant increase (p<0.05 - p<0.01) in total protein, calcium concentration and cholesterol. Males treated with 1000 and 300 mg/kg bw/day also showed a statistically significant increase (p<0.05) in albumin. Males treated with 1000 mg/kg bw/day showed a statistically significant reduction (p<0.01) in albumin/globulin ratio. Females from all treatment groups showed a statistically significant increase (p<0.05) in glucose. The majority of individual values were within the normal ranges for rats of the strain and age used. In the case of total protein, albumin and calcium concentration a true dose related response was not evident and also in the absence of any associated histology correlates the intergroup differences were considered not to be of toxicological importance.

NEUROBEHAVIOUR
Weekly open field arena observations did not reveal any treatment-related effects for treated animals when compared to controls. All inter and intra group differences in behavioural scores were considered to be a result of normal variation for rats of the strain and age used, and the differences were of no toxicological importance.
Functional Performance Tests
There were no treatment related changes in functional performance.
Statistical analysis of the data did not reveal any significant intergroup differences.
Sensory Reactivity Assessments
There were no treatment-related changes in sensory reactivity.

ORGAN WEIGHTS
No toxicologically significant effects were detected in the organ weights measured. Males treated with 1000 and 300 mg/kg bw/day showed a statistically significant reduction in thyroid weight both absolute and relative to terminal body weight. The majority of individual values were within normal range for rats of the strain and age used and in the absence of any histology correlates the intergroup differences were considered not to be of toxicological importance.

GROSS PATHOLOGY
No toxicologically significant macroscopic abnormalities were detected. One male treated with 100 mg/kg bw/day had small testes and one male treated with 300 mg/kg bw/day also had small and flaccid testes and small epididymides. Microscopic examinations revealed tubular atrophy in the testes and intratubular cellular debris and reduced sperm in the epididymides. In the absence of a similar effect at 1000 mg/kg bw/day the intergroup differences were considered not to be of toxicological importance. One female treated with 1000 mg/kg bw/day had dark kidneys at necropsy. In the absence of any histology correlates the intergroup difference was considered not to be of toxicological importance. One control male had a small and flaccid left testis and a small left epididymis. A further control male had reddened lungs. In the absence of treatment these were considered to be incidental findings.

HISTOPATHOLOGY: NON-NEOPLASTIC
There were no treatment related microscopic abnormalities detected.
The findings recorded were within the range of normal background lesions which may be recorded in rats of the strain and age used.

OTHER FINDINGS
Reproductive performance (see section 7.8.1. for further details):
There were no treatment-related effects on mating performance and fertility. There were no differences in gestation lengths. The distribution for treated females was comparable to controls.

Litter responses (see section 7.8.2. for further details):
In total eleven females from the control, 100, and 300 mg/kg bw/day dose groups and all females from the 1000 mg/kg bw/day dose group gave birth to a live litter and successfully reared young to Day 5 of age. The following assessment of litter response is based on all litters reared to termination on Day 5 of lactation/age.
No significant differences were detected for corpora lutea, implantation counts, implantation losses, litter size or litter viability for treated animals when compared to controls. Statistical analysis of the data did not reveal any significant intergroup differences. There were no intergroup differences in sex ratio (percentage male offspring) for litters from treated groups compared to controls. Statistical analysis of the data did not reveal any significant intergroup differences.There were no toxicologically significant effects detected in offspring's growth and development.

Dose descriptor:

NOAEL

Remarks:

systemic toxicity

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No toxicologically significant findings were observed in the treated animals.

Dose descriptor:

NOAEL

Remarks:

reproductive toxicity

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No effects on reproductive performance were observed.

Critical effects observed:

not specified

Conclusions:

The oral administration of 1-(3-sulphonatopropyl)pyridinium to rats by gavage, at dose levels of 100, 300 and 1000 mg/kg bw/day, did not result in any toxicologically significant effects. The "No Observed Adverse Effect Level" (NOAEL) for systemic toxicity was therefore considered to be 1000 mg/kg bw/day.
The "No Observed Effect Level" (NOEL) for reproductive toxicity was considered to be 1000 mg/kg bw/day.

Executive summary:

Introduction

The study was designed to investigate the systemic toxicity and potential adverse effects of the test item on reproduction (including offspring development) and is designed to be compatible with the requirements of the OECD Guidelines for Testing of Chemicals No. 422 “Combined Repeated Dose Toxicity Study with the Reproduction/ Developmental Toxicity Screening Test” (adopted 22 March 1996).

This study was also designed to be compatible with Commission Regulation (EC) No 440/2008 of 30 May 2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH).

Methods

The test item was administered by gavage to three groups, each of twelve male and twelve female Wistar Han™:RccHan™:WIST strain rats, for up to eight weeks (including a two week pre-pairing phase, pairing, gestation and early lactation for females), at dose levels of 100, 300 and 1000 mg/kg bw/day. A control group of twelve males and twelve females was dosed with vehicle alone (Distilled water).

Clinical signs, behavioural assessments, body weight change and food and water consumption were monitored during the study.

Pairing of animals within each dose group was undertaken on a one male: one female basis within each treatment group on Day 15 of the study, with females subsequently being allowed to litter and rear their offspring to Day 5 of lactation.

During the lactation phase, daily clinical observations were performed on all surviving offspring, together with litter size and offspring weights and assessment of surface righting reflex.

Extensive functional observations were performed on five selected males from each dose group after the completion of the pairing phase, and for five selected parental females from each dose group on Day 4 post partum. Haematology and blood chemistry were evaluated prior to termination on five selected males and females from each dose group.

Adult males were terminated on Day 43, followed by the termination of all females and offspring on Day 5 post partum. Any female which did not produce a pregnancy was terminated on or after Day 25 post coitum. Any female which did not show positive evidence of mating and did not produce a pregnancy was terminated on Day 57. All animals were subjected to a gross necropsy examination and histopathological evaluation of selected tissues was performed.

Results

Adult Responses:

Mortality

There were no treatment-related deaths.

Clinical Observations

No toxicologically significant clinical observations were detected.

Behavioural Assessment

There were no treatment-related changes in the behavioural parameters measured.

Functional Performance Tests

There were no treatment-related changes in functional performance.

Sensory Reactivity Assessments

There were no treatment-related changes in sensory reactivity.

Body Weight

There were no toxicologically significant effects in body weight development.

Food Consumption

No adverse effect on food consumption or food efficiency was detected in treated animals.

Water Consumption

No adverse effect on water consumption was detected.

Reproductive Performance

Mating:

There were no treatment-related effects on mating for treated animals.

Fertility:

There were no treatment-related effects in conception rates for treated animals.

Gestation Lengths:

There were no differences in gestation lengths. The distribution for treated females was comparable to controls.

Litter Responses:

Offspring Litter Size, Sex Ratio and Viability:

Of the litters born, litter size at birth and subsequently on Day 1 and 4 post partum was comparable to controls. Sex ratio and surface righting were also comparable to controls.

Offspring Growth and Development

Offspring bodyweight gain and litter weights at birth and subsequently on Day 1 and 4 post partum were comparable to controls. No clinically observable signs of toxicity were detected for offspring from all treatment groups.

Laboratory Investigations

Haematology:

There were no toxicologically significant effects detected in the haematological parameters examined.

Blood Chemistry:

There were no toxicologically significant effects detected in the blood chemical parameters examined.

Pathology

Necropsy

No toxicologically significant macroscopic abnormalities were detected.

Organ Weights

There were no toxicologically significant effects detected in the organ weights measured.

Histopathology

There were no treatment related microscopic abnormalities detected.

Conclusion

The oral administration of 1-(3-sulphonatopropyl)pyridinium to rats by gavage, at dose levels of 100, 300 and 1000 mg/kg bw/day, did not result in any toxicologically significant effects. The “No Observed Adverse Effect Level” (NOAEL) for systemic toxicity was therefore considered to be 1000 mg/kg bw/day. The “No Observed Effect Level” (NOEL) for reproductive toxicity was considered to be 1000 mg/kg bw/day.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 000 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

The key study is GLP compliant and is of high quality.

Additional information

The study was designed to investigate the systemic toxicity and potential adverse effects of the test item on reproduction (including offspring development) and is designed to be compatible with the requirements of the OECD Guidelines for Testing of Chemicals No. 422 “Combined Repeated Dose Toxicity Study with the Reproduction/ Developmental Toxicity Screening Test” (adopted 22 March 1996; Dunster, 2013; Report No. 41300260).

This study was also designed to be compatible with Commission Regulation (EC) No 440/2008 of 30 May 2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH).

The test item was administered by gavage to three groups, each of twelve male and twelve female Wistar Han™:RccHan™: WIST strain rats, for up to eight weeks (including a two week pre-pairing phase, pairing, gestation and early lactation for females), at dose levels of 100, 300 and 1000 mg/kg bw/day. A control group of twelve males and twelve females was dosed with vehicle alone (Distilled water).

Clinical signs, behavioural assessments, body weight change and food and water consumption were monitored during the study.

Pairing of animals within each dose group was undertaken on a one male: one female basis within each treatment group on Day 15 of the study, with females subsequently being allowed to litter and rear their offspring to Day 5 of lactation.

During the lactation phase, daily clinical observations were performed on all surviving offspring, together with litter size and offspring weights and assessment of surface righting reflex.

Extensive functional observations were performed on five selected males from each dose group after the completion of the pairing phase, and for five selected parental females from each dose group on Day 4 post partum. Haematology and blood chemistry were evaluated prior to termination on five selected males and females from each dose group.

Adult males were terminated on Day 43, followed by the termination of all females and offspring on Day 5 post partum. Any female which did not produce a pregnancy was terminated on or after Day 25 post coitum. Any female which did not show positive evidence of mating and did not produce a pregnancy was terminated on Day 57. All animals were subjected to a gross necropsy examination and histopathological evaluation of selected tissues was performed.

There were no treatment-related deaths. No toxicologically significant clinical observations were detected. There were no treatment-related changes in functional performance, sensory reactivity and in the behavioural parameters measured. There were no toxicologically significant effects in body weight development. No adverse effects on water consumption, food consumption or food efficiency were detected in treated animals.

There were no treatment-related effects on mating, fertility and gestation lenghts for treated animals. The distribution for treated females was comparable to controls. Of the litters born, litter size at birth and subsequently on Day 1 and 4 post partum was comparable to controls. Sex ratio and surface righting were also comparable to controls. Offspring bodyweight gain and litter weights at birth and subsequently on Day 1 and 4 post partum were comparable to controls. No clinically observable signs of toxicity were detected for offspring from all treatment groups.

There were no toxicologically significant effects detected in the haematological and blood chemical parameters examined. No toxicologically significant macroscopic abnormalities were detected at necropsy. Organ weights of treated groups were similar to those of controls. There were no treatment related microscopic abnormalities detected.

In conclusion, the oral administration of 1-(3-sulphonatopropyl)pyridinium to rats by gavage, at dose levels of 100, 300 and 1000 mg/kg bw/day, did not result in any toxicologically significant effects. The “No Observed Adverse Effect Level” (NOAEL) for systemic toxicity was therefore considered to be 1000 mg/kg bw/day. The “No Observed Effect Level” (NOEL) for reproductive toxicity was considered to be 1000 mg/kg bw/day.

Justification for selection of repeated dose toxicity via oral route - systemic effects endpoint:
Only one long-term study is available.

Justification for classification or non-classification

The target substance 1-(3-sulphonatopropyl)pyridinium did not cause relevant significant toxicological effects after repeated oral exposure at the highest dose level tested. Therefore, it does not meet the criteria for classification and will not require labelling, according to the European Regulation (EC) No. 1272/2008.