1,3,5-triazine-2,4,6(1H,3H,5H)-trione, trisodium salt

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Effect on fertility: via oral route

Dose descriptor:

NOAEL

602.6 mg/kg bw/day

Additional information

Read-across:

Based on the experimental results obtained with the analogue monosodium salt of cyanuric acid (NOAEL: P male ca.  470 mg/kg bw/day, P female  ca. 950 mg/kg bw/day, F1 male  ca. 500 mg/kg bw/day, F1 female  ca. 910 mg/kg bw/day, F2 male  ca. 190 mg/kg bw/day and F2 female  ca. 970 mg/kg bw/day) the read-across approach is applied and the NOAEL for substance trisodium cyanurate are calculated to be 602.6, 1218, 641.1, 1166.8, 243.6 and 1243.7

mg/kg bw/day, respectively under test conditions.

Short description of key information:
Read-across from a 3-generation reproductive study using monosodium cyanurate (equivalent to EU Method B.35), showing no biologically detrimental effect on the reproductive potential of the parents or on the growth and development of the offspring. The same results can be extrapolated to trisodium cyanurate.

Effects on developmental toxicity

Description of key information

Two pre-natal developmental toxicity studies are available. One performed in rabbits (Rodwell 1990) in rabbits and another in rats  (Laughlin 1982)

Additional information

Read-across:

1. Based on the experimental results obtained with the analogue monosodium salt of cyanuric acid (NOEL maternal toxicity =  50 mg/kg bw/day and NOEL teratogenicity =  500 mg/kg bw/day) the read-across approach is applied and the NOEL for substance trisodium cyanurate are calculated to be 64.1 mg/kg bw/day (maternal) and 641 mg/kg bw/day (teratogenicity) respectively, under test conditions.

2. Based on the experimental results obtained with the analogue monosodium salt of cyanuric acid, monohydrate (NOAEL (maternal toxicity and teratogenicity) = 5000 mg/kg bw/day) the read-across approach is applied and the NOAEL for substance trisodium cyanurate are calculated to be 5732 mg/kg bw/day (maternal toxicity and teratogenicity).

Justification for classification or non-classification

In the rat teratogenicity study, monosodium cyanurate administered by gavage did not produce a teratogenic response at a dose of 5000 mg/kg bw/day or below. In the rabbit teratogenicity study, via oral exposure, the NO(A)EL maternal toxicity based on the statistical significance of the toxicological observations is 500 mg/kg bw/day. However, there was no evidence of developmental toxicity in any of the treated groups. Hence the NO(A)EL for developmental toxicity was assessed to be at least 500 mg/kg bw/day.

Oral exposure of monosodium cyanurate in the rat fertility study did not produce any consistent effects on reproductive parameters or offspring toxicity; therefore 5375 ppm (470 - 500 mg/kg bw/day for males and 910 - 970 mg/kg bw for females) is assessed as the NOEL for CYA for reproductive and offspring effects. Under the test conditions, the NO(A)EL for adult toxicity of the monosodium cyanurate is 5375 ppm (males = 470 mg/kg bw/day, females 910 mg/kg/day) with the exception of F₂males where the NOEL = 1200 ppm (190 mg/kg/day). This is based on the related incidence of calculi in the urinary bladders of high dose animals seen at the highest dose level. On this basis no classification is warranted for cyanuric acid.

The same results can be extrapolated to trisodium cyanurate.