Troclosene sodium

Endpoint summary

Description of key information

Acute toxicity studies are available for the oral, dermal and inhalation routes. Troclosene sodium is considered harmful via the oral route but not via the dermal or inhalation route. 

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

1 671 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Value:

mg/m³ air

Acute toxicity: via dermal route

Endpoint conclusion

Value:

mg/kg bw

Additional information

The acute oral and dermal toxicity studies were performed with sodium dichloroisocyanurate dihydrate.

Justification for read across for studies with sodium dichloroisocyanurate dihydrate to troclosene sodium:

The chlorinated isocyanurates (sodium dichloroisocyanurate and sodium dichloroisocyanurate dihydrate) produce free available chlorine, in the form of hypochlorous acid (HOCl) as they dissolve in water. As the equilibria involve all of the possible chlorinated isocyanurates, the toxicity of sodium dichloroisocyanurate (NaDCC) and sodium dichloroisocyanurate dihydrate (NaDCC.2H2O) will be virtually equivalent at the same available chlorine concentration. The parent compound for all chlorinated isocyanurates is isocyanuric acid (cyanuric acid). All of the chlorinated isocyanurates are essentially equivalent, once they are dissolved in water at the low concentrations at which they are used. Therefore read across from sodium dichloroisocyanurate dihydrate is justified.

Acute toxicity: Oral route

In a acute oral toxicity study (Gargus 1985) NaDCC dihydrate was administered by gavage at 1500, 2000, 2500, 3000 and 4000 mg/kg bw to 5 male and 5 female rats. Rats were observed for clinical signs and mortality for 14 days. The acute oral LD50 value was 2094 mg/kg bw for male rats and 1671 mg/kg bw for female rats.

Acute toxicity: Dermal route

An acute dermal study is available (Gargus 1984) with NaDCC dihydrate. 5 female and 5 male rats were exposed to a limit dose of 5000 mg/kg. No deaths occurred and the LD50 was considered to be > 5000 mg/kg.

Acute toxicity: Inhalation route.

In the acute inhalation study (Dudek 1985) 5 female and 5 male rats were exposed to a whole body dust exposure of 0.27 mg/L and 1.17 mg/L of sodium dichloroisocyanurate. Six out of ten animals died when exposed to 1.17 mg/L, while none of the test animals died when exposed to test material atmosphere of 0.27 mg/L. The LD50 was therefore considered to be >0.27 < 1.17 mg/L (>270 - <1170 mg/m3) . The test material was ground to form a respirable powder. However, only a small percentage of the active material in commerce is respirable or inhalable, as most of the commercial product is marketed in granular or tableted forms which have much larger particle sizes.Therefore, the result from the inhalation study is not applicable for classification and labelling and due to the minimal potential for inhalation presented by the marketed active substance, the inhalation route will not be considered for hazard identification.

Justification for classification or non-classification

Acute toxicity oral route: In the acute toxicity study the LD50 for female rats was 1671 mg/kg. This study was considered applicable for read across to troclosene sodium which warrants a classification of acute tox cat 4 with the hazard statement: H302: Harmful if swallowed according to EU CLP regulation 1272/2008.

Acute toxicity dermal route: In the acute toxicity study the LD50 was > 5000 mg/kg. The study was considered applicable for troclosene sodium.The limit for classification for dermal toxicity is 2000 mg/kg and therefore no classification is warranted.

Acute toxicity inhalation route:

In the acute inhalation study the LD50 was considered to be >0.27 < 1.17 mg/L (equivalent to >270 - < 1170 mg/m3).

The decision for a correct classification and label also has to take into consideration whether the artificially generated conditions in the inhalation testing are relevant to characterize the hazard profile of the active substance. The Guidance to the new EU CLP regulation (1272/2008) clearly establishes that the “form or physical shape” and “reasonably expected use” of a substance is relevant for classification. Article 5(1) of 1.2 of the Guidance to the CLP establishes that “The information shall relate to the forms or physical states in which the substance is placed

on the market and in which it can reasonably be expected to be used” Furthermore, Article 8 of 1.2 defines for generating new information for substances and mixtures: “Tests that are carried out for the purposes of this Regulation shall be carried out on the substance or on the mixture in the form(s) or physical state(s) in which the substance or mixture is placed on the market and in which it can reasonably be expected to be used”.

In the study the test material was ground to form a respirable powder. However, only a small percentage of the active material in commerce is respirable (<0.06% or inhalable (<0.2%) as most of the commercial product is marketed in granular or tableted forms which have much larger particle sizes. Therefore, the result from the inhalation study is not considered to be applicable for classification and labelling and due to the minimal potential for inhalation.