Reaction mass of calcium sulfate and potassium sulfate and sodium sulphate

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Effect on fertility: via oral route

Dose descriptor:

NOAEL

1 500 mg/kg bw/day

Additional information

No data with potassic extracts are available. However, an OECD 422 study with rats shows no effects at all up to doses of 1500 mg/kg bw/day of potassium sulfate. No effects were found on reproduction parameters, neither embryotoxic or developmental effects were seen.

In a reproduction/developmental toxicity screening test (OECD guideline 422), male and female rats, were dosed with calcium sulfate, dihydrate for 35 days and 41 - 45 days respectively and the pre-mating exposure period was 14 days. No adverse effects were observed in terms of fertility, delivery and nursing in parent animals during the test period. There were no signs of reproduction/developmental toxicity on the body weight, gestation index, sex ratio, clinicals or viability up to 1,000 mg/kg/day (highest dose tested).

In a one-generation study in female mice (Andres and Cline, 1989), sodium sulfate was given in drinking water at levels up to 5000 mg/L (ca. 1790 -6560 mg/kg bw/day), beginning one week prior to breeding and up to 14 days during lactation. No differences were found in litter size, litter weaning weights or gestational or lactational weight gain of the dams among sulphate treatements. No toxicity to the dams was found. Litters were not examined histopathologically and fertility indices were not measured. Only females were treated.

In addition, in a 90 - day repeate dose toxicity study with ammonium sulfate no histological changes of testes were observed up to 1792 mg/kg bw/day. The ovaries were not examined.

No further studies are considered necessary. Potassium sulfate, calcium sulfate, dihydrate and sodium sulfate dissociates into K⁺, Ca²⁺, Na⁺ and sulphate ions. Sulfate is a normal body and nutritional component and is regulated within the body. K⁺,Ca²⁺ and Na⁺ are necessary element. Together with the available data showing no effects, an additional 2 -generation reproduction study is not considered necessary.

Short description of key information:
Potassium sulphate: no effects were found up to the highest dose tested (1500 mg/kg bw/d) (according to OECD 422).
Calcium sulfate, dihydrate: no effects in rats (according to OECD 422).
Sodium sulfate: no effects in mice.
Ammonium sulfate: no effects on reproduction organs were found and in addition in a limited one-generation study where only females were treated no effects were found.

Effects on developmental toxicity

Description of key information

Potassium sulphate: no effects were found up to the highest dose tested (1500 mg/kg bw/d) (OECD 422).  
Sodium sulfate: no visible abnormalities in litter (2800 mg/kg bw/day, days 8 through 12 of gestation, mice)
Ammonium sulphate: no effects on reproduction organs were found and in addition in a limited one-generation study where only females were treated no effects were found. 

Effect on developmental toxicity: via oral route

Dose descriptor:

NOAEL

1 500 mg/kg bw/day

Additional information

An OECD 422 study with rats shows no effects at all up to doses of 1500 mg/kg bw/day of potassium sulphate. No effects were found on reproduction parameters, neither embryotoxic or developmental effects were seen. With other sulphate compounds few studies are available relating to developmental toxicity. However, in repeated dose studies with ammonium sulphate no effects on reproduction organs were found and in addition in a limited one-generation study where only females were treated no effects were found.

In Seidenberg et al. (1986) the developmental effects of sodium sulfate in the mouse were examined as part of a validation effort of a developmental screening test. The test substance was administered (2800 mg/kg/day) by gavage on gestation days 8 through 12. No mortality, an unchanged average weight gain, and normal numbers of litters and neonates/litter were found. A 100 % perinatal survival was found, with an increased postnatal weight on day 1, normal weight at day 3 in the absence of externally visible abnormalities.

No further studies are considered necessary. Potassium sulfate, calcium sulfate, dihydrate and sodium sulfate dissociates into K⁺, Ca²⁺, Na⁺and sulphate ions. Sulfate is a normal body and nutritional component and is regulated within the body. K⁺,Ca²⁺and Na⁺are necessary element. Together with the available data showing no effects, an additional 2 -generation reproduction study is not considered necessary.

Justification for classification or non-classification

The results of the OECD screening studies with calcium sulfate, dihydrate and potassium sulfate (very high NOAEL) and data with other sulfate compounds do indicate that no classification is required for potassium sulphate according to Directive 67/548/EC and the CLP Regulation.