Potassium sulfate

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

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. No further studies with potassium sulphate were present.

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.

In a one-generation study in female mice, sodium sulphate 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.

No further studies are considered necessary. Potassium sulphate dissociates into K+ and sulphate ions. Sulphate is a normal body and nutritional component and is regulated within the body. K+ is also a necessary element of which the ADI is 2000 -4000 mg/day (Dutch Voedingscentrum). Together with the available data showing no effects, an additional 2 -generation reproduction study is not considered necessary.

Short description of key information:
In a reliable OECD screening study in rats with potassium sulphate no effects were found up to the highest dose tested (1500 mg/kg bw/d). No further studies with potassium sulphate itself were present. 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 addition, potassium sulfate dissociates into K+ and sulfate ions which are nutritional components regulated within the body. The overall conclusion for potassium sulphate is that the substance may present a hazard to fertility but only at parentally toxic doses.

Effects on developmental toxicity

Description of key information

In a reliable OECD screening study in rats with potassium sulphate no effects were found up to the highest dose tested (1500 mg/kg bw/d).  No further studies with potassium sulphate itself were present. 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 addition, potassium sulfate dissociates into K+  and sulfate ions which are nutritional components regulated within the body. The overall conclusion for potassium sulphate is that there is no evidence that the substance may present a risk for developmental toxicity.

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. No further studies with potassium sulphate were present. With other sulphate compounds also no studies are available relating to developmental toxicity. No further studies with potassium sulphate itself were present. 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.

No further studies are considered necessary. Potassium sulphate dissociates into K+ and sulphate ions. Sulphate is a normal body and nutritional component and is regulated within the body. K+ is also a necessary element of which the ADI is 2000 -4000 mg/day (Dutch Voedingscentrum). Together with the available data showing no effects, a developmental toxicity is not considered necessary.

Justification for classification or non-classification

The results of the OECD screening study (a very high NOAEL) and data with other sulphate compounds do indicate that no classification is required for potassium sulphate according to Directive 67/548/EC and the CLP directive.