Zinc nitrate

Endpoint summary

Description of key information

Assessment of the acute oral toxicity of zinc nitrate was studied in Wistar CRL/WI rats according to OECD guideline no 423 (Acute toxic Class Method) .The LD50 value was established to be greater than 300 mg/kg bw but less than 2000 mg/kg bw.
There are no specific data for zinc nitrate available on which to evaluate for acute inhalation and dermal toxicity. Read-across towards soluble zinc chloride and zinc sulphate, indicates that zinc nitrate is of very low acute inhalation and dermal toxicity not requiring a classification according to the EC criteria.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Version / remarks:

December 17, 2001

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Chemetall GmbH, lot/batch: n°14069326
- Expiration date of the lot/batch: N.I.
- Purity test date: >99.0%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: hygroscopic; keep away from sunligth, stable at room temperature

OTHER SPECIFICS:
homogeneous

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Ace Animals, Boyertown, PA
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation:
- Weight at study initiation: 206-241 g for males, 176-200 g for females
- Fasting period before study: yes: 16-20 hours prior to dosing
- Housing: in suspended wire cages
- Diet: fresh PMI Rat chow ad libitum exept for 16-20 hours prior to dosing
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): N.I, but mentioned temperature controlled
- Humidity (%): N.I.
- Air changes (per hr): N.I.
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

DOSAGE PREPARATION : the test article was mixed with distilled water to make a 20% solution (clear liquid) and to make dosing by gavage possible. The dose was based on the dry weigth of the test article.

Doses:

300 mg/kg and 2000 mg/kg

No. of animals per sex per dose:

3 males and 3 females at a dose level of 300 mg/kg
3 females at a dose level of 2000 mg/kg

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
in vivo: animals were observed 1/2, 1, 2, 3 and 4 hours postdose and once daily for 14 days for mortality, toxicity and pharmacological effects. Body weights were recorded immediately pretest, weekly, at death and at termination in the survivors
post mortem: all animals were humanely sacrificed using CO2 and were examined for gross pathology following study termination. Abnormal tissues were preserved in 10% neutral buffered formalin for possible future histological examination

Statistics:

N.I.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 300 mg/kg bw

Based on:

test mat.

Remarks on result:

other: all six animals survived at 300mg/kg bw

Sex:

female

Dose descriptor:

LD50

Effect level:

< 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: 2 of 3 females died at 2000 mg/kg bw; 1 animal was sacrificed due to moribund condition within 5 hours following gavage

Mortality:

2 of 3 females at a dose level of 2000 mg/kg/bw
no mortality at a dose level of 300 mg/kg/bw

Clinical signs:

other: at 300 mg/kg bw: no abnormal physical signs at 2000 mg/kg bw: abnormal physical signs of lethargy, piloerection, prostration, soiling/wetness of the anogenictal area and lacrimation

Gross pathology:

at 300 mg/kg bw: all necropsy results were normal
at 2000 mg/kg bw: necropsy results revealed opaqueness of the eyes, wetness/staining of the anogenital area and abnormalities of the gastrointestinal tract (pale/hardened stomach and red/yellow areas in the intestines)

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

LD50 is greater then 300mg/kg bw but less than 2000 mg/kg bw in rats and therefore considered to be in acute toxic category 4

Executive summary:

The potential for oral toxicity was determined using the acute toxic class determination (OECD guideline no. 423).

3 healthy male and 3 healty female Sprague Dawley rats were dosed orally with zinc nitrate hexahydrate at 300 mg/kg. Since there was no oral toxicity, and addition three female Sprague Dawley rats were dosed at 2000 mg/kg.

At 300 mg/kg: all 6 animals survived the single 300 mg/kg oral dose. At 2000 mg/kg: 2 of 3 females died.

The LD50 is greater than 300 mg/kg but less than 2000 mg/kg bw in rats

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

300 mg/kg bw

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Used in EU risk assessment report for zinc sulphate

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Type of coverage:

semiocclusive

Vehicle:

not specified

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

Details on study design:

observation period of 15 days

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

none

Clinical signs:

other: no effects

Gross pathology:

no effects

Interpretation of results:

GHS criteria not met

Conclusions:

LD50 dermal is >2000 mg/kg bwZinc sulphate is not harmful or toxic via the dermal route

Executive summary:

In this study zinc sulphate heptahydrate was administered to the skin of five Wistar rats of each sex at 2000 mg/kg bw for 24 hours. Animals were observed for 15 days. Clinical signs of toxicity consisted of erythema (grade 1 and 2, of maximum grade 4), scales and/or scabs (scale 1 and 2, of maximum scale 3) in the treated skin area between observation days 2-8.

Zinc sulphate is not harmful or toxic via the dermal route.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

Zinc chloride demonstrated acute toxicity via the inhalation route (LC₅₀≤ 1,975 mg/m³). However, since the exposure of the animals to the size of the particles is not truly representative of exposure to humans under normal conditions, it is difficult to assess whether or not, zinc chloride is acutely toxic since a four hour LC₅₀value could not be derived and a clear dose-response relationhip coud not be established. Airway irritation has been observed both in animals and in humans, zinc chloride has the potential to be a respiratory tract irritant.

Zinc sulphate is not acutely toxic via the dermal route (LD50 >2,000 mg/kg bw). Effects of inhalation exposure to zinc sulphate were limited to pulmonary effects only.

Justification for classification or non-classification

Soluble zinc nitrate is harmful following acute oral exposure (300 > LD50 < 2000 mg/kg bw) and meets the classification criteria for harmful if swallowed: Acute Tox. Cat. 4: H332.

There are no specific data for zinc nitrate available on which to evaluate for acute inhalation and dermal toxicity. Read-across towards soluble zinc chloride and zinc sulphate, indicates that zinc nitrate is of very low acute inhalation and dermal toxicity not requiring a classification according to the EC criteria.