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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Key value for chemical safety assessment

Effects on fertility

Additional information

Reproductive toxicity studies of acetone cyanohydrin, sodium cyanide and potassium cyanide are all informative toward understanding the reproductive effects of hydrogen cyanide. Regardless of whether the exposure is to gaseous HCN or ACH, or via a soluble cyanide salt, it is HCN which is absorbed into the blood after oral, dermal or inhalation exposure. The form of cyanide to which exposure takes place, i.e. a simple salt or the free acid, does not influence the distribution, metabolism or excretion from the body. 

 

There is limited information available from the report of a 13-week subchronic study of NaCN in the drinking water of F344 rats and B6C3F1 mice at doses of up to 12.5 and 26.5 mg CN ion/kg bw/d, respectively (Hebert, 1993). While minor effects were seen in cauda epididymal weight, sperm motility and sperm head counts, the effects are likely related to water restriction, dehydration and resultant stress.  Water restriction was also observed in a 13-week subchronic study of KCN in CD rats at significantly higher doses (up to 160 mg KCN/kg bw/day).  An additional control group of animals which received equivalent amounts of water as the high dose KCN group demonstrated comparable decreases in body and organ weights (including testes), indicating that cyanide was not the causative agent in the organ weight changes. The NOAEL for testes effects was 80 mg/kg bw/d, equivalent to 32 mg CN-/kg bw/d.

 

The only studies that give a clear indication of the relative sensitivity of the reproductive system are those that have used ACH. ACH showed no evidence of teratogenic effects following gavage dosing in rats up to and including doses that produced maternal toxicity. In male and female fertility studies in rats, inhaled ACH showed no reproductive effects up to concentrations that were limited by the threshold to acute toxicity, equivalent to 56 mg CN-/m3 or 160 mg KCN/m3.


Short description of key information:
Fertility studies on acetone cyanohydrin provide a clear indication of the relative sensitivity of the reproductive system compared to systemic toxicity. ACH showed no evidence of teratogenic effects following gavage dosing in rats up to and including doses that produced maternal toxicity. In male and female fertility studies in rats, inhaled ACH showed no reproductive effects up to concentrations that were limited by the threshold to acute toxicity, equivalent to 56 mg CN-/m3 or 160 mg KCN/m3. In teratology studies, no malformations were noted in offspring of rats exposed to oral concentrations of KCN.

Effects on developmental toxicity

Description of key information
A standard teratology protocol was used in an oral study of acetone cyanohydrin at concentrations of 0, 1, 3 and 10 mg/kg bw/day .    The incidence of fetal malformations and developmental variations was comparable between test and control groups.   Acetone cyanohydrin did not elicit a teratogenic response when administered by the oral route to Charles River rats at  10 mg/kg/day. 

Toxicity to reproduction: other studies

Additional information

There are two fertility studies with acetone cyanohydrin (ACH), one for male and one for female fertility. There were no effects on fertility observed when ACH was exposed by inhalation up to concentrations, limited by the threshold of acute lethality, to male or female rats. In a teratology study of ACH in rats, there were no differences in the incidence of fetal malformations and developmental variations between fetuses of treated rats and controls. Subchronic studies of sodium cyanide or potassium cyanide which have suggested minor effects on male reproduction have been confounded by fluid restriction and stress, as evidenced by similar findings in controls provided comparable water supplies.

Justification for classification or non-classification

Potassium cyanide does not cause adverse effects to the reproductive system or to developing organisms at concentrations below those causing adult systemic toxicity.

Additional information