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Administrative data

Link to relevant study record(s)

Description of key information

The available studies show a very low dermal penetration rate of the test item.

Key value for chemical safety assessment

Additional information

To date, three different studies (two in-vitro; 1 in-vivo) describing dermal absorption of the test item butyl methoxydibenzoylmethane (BMDBM) are available:

Darragh 1980: Radioactivity from radio-labelled BMDBM was detected only on skin surface. Minor proportions (<1%) were adsorbed in the stratum corneum. In plasma and feces no radioactivity and in urine a very low percentage (<0.1%) could be recovered.

Kleczak 1982: Results showed that almost the whole part of topically applied BMDBM (95%) remained on the skin surface. 1.0 -1.7% were adsorbed on the stratum corneum, 0.9-3.4% absorbed in the skin and only a minimum (<=0.5%) was found to pass the skin. Skin absorption/penetration was not affected by the different vehicles.

Stuttgen 1982: After dermal application of BMDBM, no penetration into the receptor fluid was observed. Dermal absorption increased with exposure time. From this it follows that more than 84% of the applied dose remained on the skin surface.

 

In these three studies only minimal dermal penetration of BMDBM after topical administration was observed. In all studies, the majority of the applied dose remained on the skin surface and only a minor percentage was absorbed into epidermis or dermis. Systemic uptake and excretion of BMDBM in the body was only evaluated by Darragh et al. (1980). They found a minor proportion in urine but no BMDBM in plasma or feces.

Edwards 2009: in this key study was discussed, that the molecular weight of BMDBM is in the range (MW<500 D) were skin penetration can occur but the log Pow is slightly above the range favoring penetration (log Pow in range -1 to +4), i.e. 4.5 as calculated by EPIWIN. Meanwhile, a log Pow value of 6.1 was determined experimentally for BMDBM (Weissenfeld, 2010), but this result does not change the interpretation of percutaneous absorption since the value is above of the optimal penetration range. This finding could be confirmed the in vitro study results where majority of the applied dose remained on the skin surface.