Lithium tetrafluoroborate, anhydrous

Toxicity to reproduction

Administrative data

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Lithium tetrafluoroborate, anhydrous

EC Number:

238-178-9

EC Name:

Lithium tetrafluoroborate, anhydrous

Cas Number:

14283-07-9

Molecular formula:

BF4.Li

IUPAC Name:

lithium tetrafluoroborate, anhydrous

Test material form:

solid: particulate/powder

Test animals

Species:

rat

Strain:

Wistar

Details on species / strain selection:

The study was designed to evaluate the potential toxic effect of the test itemLithium Tetrafluoroborate when administered to rats for a minimum of 28 days and to evaluate the potential of the test item to affect male and female reproductive performance such as gonadal function, mating behaviour, conception, parturition, and early postnatal development.

Sex:

male/female

Details on test animals or test system and environmental conditions:

All animals were observed twice daily for mortality and morbidity. Detailed clinical observations, body weights, and food consumption were recorded weekly. Functional Observational Battery (Open field test, Tail flick test and Grip-strength test) were recorded for 5males at the end of dosing, for 5females during the last week of lactation shortly before scheduled kill and in satellite animals at the end of in-life phase.
Females were allowed to deliver and rear their pups until lactation Day 13. Live pups were counted and sexed and litters weighed. The anogenital distance (AGD) of each pup was measured on Day 4 post-partum. Any abnormal behavior of the offspring was recorded. The number of nipples/areolae in male and female pups were counted on post-natal Day 13 (PND 13).
The urinalysis was performed in five randomly selected males of each group during the last week of the treatment and in satellite animals using urine volume collected from animals in metabolic cages during 6 hours.
Clinical pathology evaluations (haematology, coagulation, and clinical chemistry) were performed in half males and all females and in satellite animals at the end of in-life phase. Thyroxine level was assayed in parent rats and pups PND 13 and PND 4.
The pups were euthanized on PND 13 and examinated for gross abnormalities with particular attention to the the reproduction organs and the thyroid glands were preserved.From all adult males and females and one male and female pup Day 13 from each litter thyroid glands were preserved.The weight of thyroid glands in adults was determined.
Animals were subjected to gross necropsy. Complete necropsies were conducted on all animals and satellite animals, and selected organs were weighed.Selected tissues were examined microscopically from 5 males and 5 females in the vehicle control and high-dose groups from main subgroup; organs of the reproductive system in all males and females in the vehicle control and high-dose groups.

Administration / exposure

Route of administration:

oral: gavage

Remarks on MMAD:

The test item, Lithium Tetrafluoroboratein the vehicle aqua pro injection, was administered by gavage once daily to three groups ofWistar rats at the doses of 50, 150 and 250 mg/kg. A concurrent vehicle control group received the vehicle (aqua pro injection) on a comparable regimen and in the same volume of 2mL/kg. The females (13per group) were screened for normal oestrous cycles in a 2-week pre-treatment period.
Each group consisted of 10 males; all females were used for dosing and mating. After mating, 10 females, showing evidence copulation were used in each group.
Males were administrated 14 daily doses prior to mating and continuing throughout the mating period, for a total of 28 doses. Females received 14 daily doses prior to mating and were dosed through mating, gestation and lactation (13 days).
Satellite animals (five males and five females from control group and high dose group) were not mated, administrated for a total 28 doses, males and 54 doses, females, and euthanized after two-week recovery period.

Vehicle:

other: aqua pro injection

Details on exposure:

The test item, Lithium Tetrafluoroboratein the vehicle aqua pro injection, was administered by gavage once daily to three groups ofWistar rats at the doses of 50, 150 and 250 mg/kg. A concurrent vehicle control group received the vehicle (aqua pro injection) on a comparable regimen and in the same volume of 2mL/kg. The females (13per group) were screened for normal oestrous cycles in a 2-week pre-treatment period.
Each group consisted of 10 males; all females were used for dosing and mating. After mating, 10 females, showing evidence copulation were used in each group.
Males were administrated 14 daily doses prior to mating and continuing throughout the mating period, for a total of 28 doses. Females received 14 daily doses prior to mating and were dosed through mating, gestation and lactation (13 days).
Satellite animals (five males and five females from control group and high dose group) were not mated, administrated for a total 28 doses, males and 54 doses, females, and euthanized after two-week recovery period.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Each animal was marked with an ID number. Each cage was affixed with a cage card containing pertinent animal and study information. The animals in cages were marked by a line on the tail with an ink marker.
Number of animals in cage was according period of study:
• Pre-treatment period (14 days) – 5 animals per cage
• Pre-mating (14 days) –5 animals per cage
• Mating (maximum 14 days)- 1 male/1 female per cage
• Gestation (approximately 22 days) - 1 female per cage
• Post-partum (13 days) - 1 female with offspring per cage
Satellite animals – 5 animals per cage during all the study
The test item was administered in a single dose by gavage using a metal stomach tube.Administration volume was 2 mL/kg. For each animal the individual dosing volume was calculated on the basis of the actual body weight.

Duration of treatment / exposure:

The animals were dosed daily for 7 days a week.

Frequency of treatment:

daily

Control animals:

yes, concurrent vehicle

Examinations

Statistics:

Individual results (the body weight, food consumption, haematology, clinical chemistry, relative
weights of organs and reproduction parameters) obtained during the study were statistically
evaluated by statistical programme Statgraphics. Statistical evaluation was done separately for
males and females. Basic statistic (mean, sd) was made and Kruskal – Wallis test was applied. In
the case of statistically significant result the Kruskal Wallis test was followed by Mann Whitney W
test to determine which medians are significantly different from the one in control group.
Significance level of 0.05 was considered to make relevant statistical conclusions.

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

During the study mortality of animals was recorded. Two males of High dose, male ID43 died on Day 14 and male ID 39 on Day 15 of the treatment. Males of High dose satellite (ID 46, 47, 48 and 50) died between Day 16 and 23 of the treatment. Lethargy, piloerection and nose-bleed in males was registered before death.All other males at lower dosage levels survived without significant visible clinical signs.

Mortality:

no mortality observed

Description (incidence):

No mortality in females was registered. All females at all dosage levels survived to the scheduled necropsy without significant visible clinical signs.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

At the start of the study average body weights were 284.9 g males and 217.15 g females. The animals were divided into the groups according to the body weight. The variation of animal body weights no exceeded ± 5% of the mean weight for each sex.
No differences between body weight of control and dose groups were registered in males.
At the commencement of the study, the weight variation of animals in the dose groups was about 5%; after statistical evaluation significant differences were observed.Statistically significant differences between Control and Low andMid dose on Day 1 of treatment in females were observed.
Decrease of body weight of all dose group against Control was registered from Day 7 of the treatment. Decrease of the body weight of all dose groups continued up to the end of treatment (lactation Day 13).The body weight of High dose-satellite females was similar in comparison with recovery Control females during the whole study.

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

Food consumption of males and females of all dose groups was similar to thecontrol males during the whole study.Food consumption of satellite females was similar in comparison with Control.

Haematological findings:

no effects observed

Description (incidence and severity):

Only decreased value of prothrombin time (PT) of males of High dose against Control was recorded.
Statistically significant differences between Control and Mid dose of erythrocytes (RBC), haematocrit (HCT) and monocytes (Mon) in females of Low dose; in case of Mon also in females of High dose were registered. The changes were of small magnitude and was not considered as a toxicologically important.
No differences in satellite females were noticed.
During the study, haematology parameters in both sexes were within or close to the historical control data for this species. No test item related effects on the haematology parameters were observed in this study.

Clinical biochemistry findings:

no effects observed

Description (incidence and severity):

Statistically significant higher concentration of total cholesterol (CHOL) and triacylglycerol (TAG) and lower concentration of urea, calcium (Cal) and inorganic phosphorus (PHOS) were observed in males of High dose when compared to the Control group. Males of Mid dose had significant increase of concentration of urea and decrease concentration of Cal and PHOS against Control. Statistically significant decrease of CHOL and PHOS and increase of urea in males of Low dose against Control were registered.
No significant differences were observed in monitored parameters of female rats.
These sporadic changes had no dose relationship; they were considered to be a result of intra-individual and inter-individual variability for this species or they have only statistical character.
The average values of clinical chemistry parameters in all animals were within or slightly outside the serum historical control data.There were no findings in clinical chemistry parameters which could be definitively attributed to the treatment.

Urinalysis findings:

effects observed, treatment-related

Description (incidence and severity):

In the urine of some animals, small amounts of protein, ketones and presence of leukocytes were observed. There are no differences between Control and the dose groups and these findings can be consideredclose to normal (7).In males of Mid and High dose groups the increased diuresis was observed. The volume of urine, collected during 6 hours, was about 3 times higher than in males of Control group.

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Description (incidence and severity):

Incidental finding of lymphoepithelioid granuloma (37 M/HD) in CE (caecum) is supposed to be induced by stress factors. Psychological stress may increase gastrointestinal permeability allowing luminal constituents access to the mucosal immune system (9). We have found lymphoepitheliod granulomas also in earlier examined toxicological studies in control rats (non-published). Lesions are not related with the test item administration.

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

no effects observed

Effect levels (P0)

Dose descriptor:

NOAEL

Effect level:

ca. 50 mg/kg bw/day (nominal)

Sex:

male/female

Basis for effect level:

body weight and weight gain

Results: F1 generation

General toxicity (F1)

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Effect levels (F1)

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

< 50 mg/kg bw/day (nominal)

Sex:

male/female

Basis for effect level:

clinical signs

Overall reproductive toxicity

Reproductive effects observed:

no

Lowest effective dose / conc.:

50 mg/kg bw/day (nominal)

Treatment related:

no

Any other information on results incl. tables

After consideration of the study results following conclusions were maderegarding the test itemLithium Tetrafluoroborate.

The test item administration

-      had no visible toxic effect on females and male of Low and Mid dose

-      had no impact on body weight and food intake in males and females

-      had no influence on monitored haematological and clinical chemistry parameters males and females

-      had no influence on the reaction time males and females and grip strength in males

-      did not cause histopathological changes on the examined organs

The test item administration

-      caused mortalityand had toxic effecton males of High dose (250 mg/kg/bw)

-      caused increase of diuresis in males of Mid (150 mg/kg/bw) and High dose (250 mg/kg/bw)

-      caused decreaseof muscle strength infemales of Mid (150 mg/kg/bw) and High dose (250 mg/kg/bw)

-      caused depress oflocomotor activity males of High dose (250 mg/kg/bw), females of Mid (150 mg/kg/bw) and High dose (250 mg/kg/bw)

-      caused increase relative weight adrenal, prostate and thyroid in males of Mid dose (150mg/kg/bw) and increase relative weight of kidney, adrenal, prostate and thyroid in males of  High dose (250 mg/kg/bw)

-      caused increase relative weight of thyroid in females of High dose (250 mg/kg/bw)

The test item administration

-      caused decrease number of implants in High dose (250 mg/kg/bw)

-      caused decrease oflive pups at Day 1 and Day 4 post-partum in Mid (150 mg/kg/bw) and High  dose (250 mg/kg/bw)

-      caused decrease oflitter weight at Day 1 post- and at Day 4 PP in High dose (250 mg/kg/bw)

-      impacted the length of pregnancy in all doses

-      caused decrease bodyweight of mothers at birth in all doses

-      caused increase post-implantation losses in High dose (250 mg/kg/bw)

-      caused increase concentration T4 in F1 offspring at Day 13 post-partum; male pups of Mid (150mg/kg/bw) and High dose (250 mg/kg/bw) and female pups of all doses

Applicant's summary and conclusion

Conclusions:

Based on these results of this study
- the no-observed-adverse-effect-level (NOAEL) of Lithium Tetrafluoroboratein the systemic toxicity for Wistar rats was concluded to be 50 mg/kg/body weight
- the NOAEL of Lithium Tetrafluoroborate in the reproduction toxicityforWistar rats was concluded to be less than 50 mg/kg/body weight