Registration Dossier

Diss Factsheets

Administrative data

Description of key information

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:
adverse effect observed (irritating)

Additional information

Skin irritation

Reliable in vitro and in vivo skin irritation studies conducted on the three cobalt carboxylates (GLP compliant) are considered to be reliable without restrictions. As cobalt(2+) C2/C8/C20 carboxylates salts composition is a combination of the 3 cobalt carboxylates tested for skin, conclusions on skin irritation in the 3 compounds can thus be used to conclude in a similar way for the Cobalt(2 +) C2/C8/C20 carboxylates salts.

According to (EC) No. 1272/2008, and subsequent regulations, none of the 3 carboxylates is classified as skin irritant. As a consequence, cobalt(2 +) C2/C8/C20 carboxylates salts does not need to be classified as skin irritant as per Regulation

(EC) No. 1272/2008.

Eye irritation

Two reliable in vitro studies described by Heppenheimer conducted on cobalt bis(2 -ethylhexanoate) and cobalt diacetate carboxylates (OECD 437; GLP compliant) are considered to be reliable without restrictions. The threshold of the mean in vitro irritation score for corrosivity / severe irritancy is a score equal or higher than 55.1. The 2 eye irritation scores are clearly below this threshold.

Three reliable in vivo studies described by Mallaun, Pelcot and Sanders conducted on the three cobalt carboxylates (OECD 405; GLP compliant) are considered to be reliable without restrictions. cobalt bis(2-ethylhexanoate) and cobalt diacetate were determined to cause irritating effects on the eye. As a worst case approach, cobalt(2 +) C2/C8/C20 carboxylates salts can thus be considered as irritating to the eye.


Effects on eye irritation: irritating

Justification for classification or non-classification

Skin irritation

References Heppenheimer, Pelcot and Kukulinski are the key studies for skin irritation and will be used for classification. In the reference Pelcot (OECD 404), the cobalt resinate was irritant when applied topically to rabbits under experimental conditions.According to Regulation (EC) 1272/2008 and subsequent amendments and as a worst case approach, cobalt(2 +) C2/C8/C20 carboxylates salts does not need to be classified as skin irritant.

Eye irritation

According to Mallaun (2011) the overall irritation results 24, 48 and 72 hours after application of cobalt bis(2 -ethylhexanoate) per animal are as follows:

- Corneal opacity = 0.00, 1, 1

- Iris light reflex = 0.00 for all three animals

- Conjunctival redness = 1.00, 3.00, 2.33

- Conjunctival oedema = 0.00, 1.33, 1.33

According to Sanders (2013) the overall irritation results 24, 48 and 72 hours after application of cobalt diacetate per animal are as follows:

- Corneal opacity = 0 for both animals

- Iris light reflex = 0 and 0.33

- Conjunctival redness =2 for both animals

- Conjunctival oedema = 1.67 and 1.33

The classification criteria acc. to regulation (EC) 1272/2008 as irritating to eyes are met for both cobalt bis(2 -ethylhexanoate) and cobalt diacetate.

Thus, as a worst case approach, the Salt reaction of cobalt(2 +) and C2/C8/C20 carboxylates will be classified as eye irritant (Category 2; H319) according to regulation (EC) 1272/2008.