Kaolin, calcined

Endpoint summary

Description of key information

Skin:
Not irritating to skin (RA Kaolin clay polydimethylsiloxane; rabbit, semiocclusive 4 h)
Eye:
Not irritating to eye (RA Kaolin; rabbit, 0.1 mL)

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

Skin irritation

There is only a short abstract available for the skin irritating potential of Kaolin, calcined (KPC Europe 2005, RL4). Therefore read-across was conducted from the structurally related substances Kaolin clay polydimethylsiloxane, silicic acid, aluminium salt (in vitro test) and the FCC catalysts CCZ-44 and FCC CBZ-1 (catalysts contain up to 45% Kaolin, calcined).

 

In vivo

In an acute skin irritation/corrosion test with three New Zealand White rabbits according to GLP-guideline 404 no effects on skin (edema or erythema, respectively) were detected after 4 hours semiocclusive treatment with Kaolin, calcined (KPC Europe, 2005, RL4).

 

Kaolin clay polydimethylsiloxane was tested for acute dermal irritation/corrosion in a GLP-guideline study according to OECD Guideline 404 (Engelhard Corp., 1997, RL2).

0.5 gram of the test substance, as 50% (w/w) mixture in distilled water was applied semiocclusive in a single dose to the skin of six New Zealand White rabbits for 4 hours. The observation period was terminated at 72 hours instead of 14 days, since no signs for dermal irritation (edema or erythema, respectively) were noted at any reading time point after patch removal. Furthermore, there were no sign of gross toxicity.

 

The skin irritating potential of the FCC catalysts CCZ-44 and CBZ-1 were determined in a non-GLP study (Calkins and Ward, 1976, RL2). The test substances were applied at 2000 mg/kg bw to the intact skin of 5 rabbits each for 24 hours under occlusive conditions. No signs of erythema or edema were noted at the treatment sites in any animal during the 48 hour observation period.

 

In vitro

The skin irritation potential of silicic acid, aluminium salt was determined (Paulus, 2010; RL2) according to OECD guideline (Draft proposal for a new guideline. In vitro skin irritation: human skin model test, Dezember, 2007). Approx. 25 mg of the test item were applied to EpiDermTM tissues. After 35 minutes incubation tissues were rinsed and incubated for further 42 hours. The cell viability was measured photometric by dehydrogenase conversion of MTT. No decrease of cell viability was detected compared to the negative control. Under these test conditions the substance has no skin irritation potential.

Eye irritation

Except of one short abstract (KPC Europe 2005, RL4), no data were located for Kaolin, calcined regarding eye irritation/corrosion. Therefore the structurally-related compounds Kaolin and the FCC catalysts CCZ-44 and CBZ-1 (catalysts contain up to 45% Kaolin, calcined) were taken into account.

In vivo

In an acute eye irritation/corrosion test with three New Zealand White rabbits according to GLP-guideline 404, available as short abstract only, an average grade for redness (conjuntivae) of 0.4 was recorded after treatment with Kaolin, calcined (KPC Europe, 2005, RL4). Other ocular reactions could not be detected.

 

The acute eye irritation of the read-across substance Kaolin was investigated in a GLP-guideline study (EPA OPPTS 870.2400) in rabbits (Engelhard Corp., 2000, RL2). 0.1 mL (0.04-0.05 g) of the test substance was instilled into the right eye of one male and two female New Zealand White strain rabbits (no washout). The left eye, which remarks untreated, served as control. The resulting ocular reaction to the substance was evaluated by the method of Draize 1, 24, 48 and 72 hours after treatment. One hour following test substance installation, all three treated eyes exhibited conjunctivitis. The overall incidence and severity decreased thereafter. By 48 hours all animals were free of ocular irritation. There were no other signs of gross toxicity.

 

FCC catalysts CCZ-44 and FCC CBZ-1 were tested in eye irritation studies in rabbits according to the guideline of the Department of Transportation, Code of Federal Regulations, Title 49, Part 173 (Calkins and Ward, 1976, RL2). 100 mg of the test substances were instilled into the conjunctival sac of the right eye of six New Zealand White rabbits each without washing off. The untreated eye of the same animal served as control. The FCC catalysts CCZ-44 and CBZ-1 are not considered as ocular irritant since no eye effects were noted up to 72 hours.

 

 

Respiratory irritation

No data available.

Justification for classification or non-classification

Based on the results obtained, Kaolin, calcined does not fulfill the criteria to be classified for eye or skin irritation/corrosion according to DSD (67/548/EEC) or CLP (1272/2008/EC).