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Administrative data

Description of key information

Assessment of the acute oral toxicity of zinc sulphate was studied in Sprague-Dawley or Wistar rats and Swiss mouse according to OECD guideline no 401 or 423. Soluble zinc sulphate (monohydrate, hexahydrate and heptahydrate) has LD50 oral values ranging from 574 to 2,949 mg/kg bw, 862 to 4,429 mg/kg bw and 920 to 4,725 mg/kg bw, respectively for the three forms of zinc sulphate. Effects of inhalation exposure to zinc sulphate were limited to pulmonary effects only. Assessment of acute dermal toxicity was studied on the skin of Wistar rats  at 2000 mg/kg bw  for 24 hours (OECD guideline no 402) demonstrating zinc sulphate is not acutely toxic via the dermal route (LD50 >2,000 mg/kg bw)

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:
supporting study
Study period:
Not reported
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Used in EU risk assessment for zinc sulphate, Study well documented, meets generally accepted scientific principles, acceptable for assessment
Reason / purpose:
reference to same study
Qualifier:
according to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
yes
Remarks:
(No data about doses, controls, observation frequency, fasting period before study, age at study initiation, housing of animals)
Principles of method if other than guideline:
Not applicable
GLP compliance:
no
Test type:
standard acute method
Limit test:
no
Species:
rat
Strain:
Sprague-Dawley
Sex:
male
Details on test animals and environmental conditions:
for more information refer to reference
Route of administration:
oral: gavage
Vehicle:
other: suspended in 0.85% saline
Details on oral exposure:
animals were observed for 10 days


DOSAGE PREPARATION: Solutions were administered at pH between 6.0 and 7.0. Sodium bicarbonate was used to adjust the pH when necessary.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: A preliminary screening with small groups of 3 animals was carried out The LD50 values were then calculated according to the Litchfield and Wilcoxon method.
Doses:
50 , 100, 500, 1000 and 3000 mg/kg
No. of animals per sex per dose:
5 animals per dose
Control animals:
not specified
Details on study design:
see reference
Statistics:
No data
Sex:
male
Dose descriptor:
LD50
Effect level:
920 mg/kg bw
Mortality:
no information
Clinical signs:
see reference
Body weight:
see reference
Gross pathology:
reddened stomach and intestinal mucosa
Other findings:
No data
Interpretation of results:
harmful
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
LD50 is 920 mg/kg bw
Executive summary:

In an acute oral study zinc sulphate (type not specified, only “Zinc sulphate, Rayon”) was suspended in 0.85% saline and administered to male Sprague Dawley rats by intubation. Dose levels were 50, 100, 500, 1000 and 3000 mg/kg (5 animals per dose). Animals were observed for ten days. Toxicity signs were reddened stomach and intestinal mucosa. The LD50value was determined as 920 mg/kg bw zinc sulphate.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed
Dose descriptor:
LD50
574 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:
other: Used in EU risk assessment report for zinc sulphate, meets generally accepted scientific principles, acceptable for assessment
Qualifier:
according to
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:
no effects
Body weight:
no effects
Gross pathology:
no effects
Interpretation of results:
practically nontoxic
Remarks:
Migrated information Criteria used for interpretation of results: EU
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
2 000 mg/kg bw

Additional information

Soluble zinc chloride is harmful following acute oral exposure (LD50range 1,100 to 1,260 mg/kg bw). Zinc chloride has also 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.

Soluble zinc sulphate (monohydrate, hexahydrate and heptahydrate) has LD50oral values ranging from 574 to 2,949 mg/kg bw, 862 to 4,429 mg/kg bw and 920 to 4,725 mg/kg bw, respectively for the three forms of zinc sulphate. 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.

Soluble zinc bis(dihydrogen phosphate) is also harmful following acute oral exposure (LD50 range >300 to <2000 mg/kg bw).

While no specific acute toxicity data were identified for diammonium tetrachlorozincate and triammonium pentachlorozincate, it is (due to its similar solubility characteristics) likely to display a toxicity profile similar to that of zinc chloride, zinc sulphate or zinc bis(dihydrogen phosphate).


Justification for selection of acute toxicity – oral endpoint
Lowest LD50 value.
zinc sulphate (monohydrate, hexahydrate and heptahydrate) has LD50oral values ranging from 574 to 2,949 mg/kg bw, 862 to 4,429 mg/kg bw and920 to 4,725 mg/kg bw, respectively for the three forms of zinc sulphate

Justification for classification or non-classification

Soluble zinc sulphate (monohydrate, hexahydrate and heptahydrate) has LD50oral values ranging from 574 to 2,949 mg/kg bw, 862 to 4,429 mg/kg bw and 920 to 4,725 mg/kg bw, respectively for the three forms of zinc sulphate and is classified as harmful if swallowed (Xn; R22 or Acute Tox.Cat.4: H302 ) according EC criteria. 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.