Registration Dossier

Administrative data

Description of key information

Oral: OECD 425, LD50 female rats, no adverse effects observed. Not classified as acutely toxic by the oral route. Reliability = 1.
Dermal: OECD 402. LD50, rat. No adverse effects observed. Not classified as acutely toxic by the dermal route. Reliability = 1.
Inhalation: 47 mg a.i./m3 bw. Lethality, pulmonary edema. Aqueous dispersion of TNS administered, Determination of threshold for lethality, Classification for acute toxicity by inhalation is proposed. Reliability = 2

Key value for chemical safety assessment

Acute toxicity: via inhalation route

Endpoint conclusion
Dose descriptor:
discriminating conc.
47 mg/m³

Additional information

The Notified Substance (TNS) was tested for acute oral, dermal and inhalation toxicity. The aqueous dispersion of TNS (~20% solids and ~80% water) was administered directly without correction for active ingredient since the product does not exist as TNS alone and is always transported and used as the aqueous dispersion. The material was not toxic via the oral or dermal routes of exposure as evidenced by LD50 values of > 5000 mg/kg. This is equivalent to an approximate LD50 > 1000 mg a. i. / kg or TNS, as the aqueous dispersion was administered in this study.  An acute inhalation toxicity study was conducted on this multi-constituent substance. The Approximate Lethal Concentration (ALC) or threshold for lethality was the resulting endpoint from this study and was determined to be 47 mg a. i. /m3 (respirable particulate), indicating the material may be toxic upon inhalation of respirable particulate (aerosol). TNS is not expected to be present in the vapour form, therefore it would not pose the same hazard. A full LC50 evaluation has not been conducted on this material nor any similar substance. However, an acute toxicity estimation (ATE) can be used to determine a classification category. Therefore, the ATE is 0.005 mg/L and this value will be used to make an acute inhalation classification.

Justification for classification or non-classification

The TNS is not classified for acute oral toxicity as the LD50 was determined to be > 1000 mg a. i. /kg and the LD50 for Zonyl was > 25,000 mg/kg. Similarly, it is not classified for dermal toxicity as the LD50 for this route of exposure was also > 1000 mg a. i. /kg and given the very low bioavailability as evidenced by a lack of toxic effects in the Zonyl acute and subchronic exposure studies. TNS does not need to be classified for acute oral or dermal toxicity according to EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008. A full LC50 determination has not been made for this substance nor for any similar substance, however, the ATE of 0.005 mg/L, indicates the CLP classification of Cat. 1 should be used for classification of this material.