Aluminum, dross

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Additional information

A study on the effects of Aluminium dross on reproduction in terms of fertility, as is normally investigated by means of a standard two-generation toxicity study, is not justified on the following scientific grounds .

·        No fertility tests have been performed with aluminium dross. Therefore a read-across approach was utilized, based on its constituents. The main constituents of aluminium dross are metallic Aluminium, Aluminium oxide and Aluminium nitride, which degrades into Aluminium hydroxide and ammonia.Effects on the endpoints measured in these studies are typically the results of systemic exposure. The endpoints, as they may occur in the endocrine glands involved in the regulation of pregnancy, the placenta, the uterus, and the embryo can only be reached by test compounds via the blood, at least when normal, non-invasive exposure routes are applied.

-Effects on the endpoints measured in these studies are typically the results of systemic exposure. The endpoints, as they may occur in the endocrine glands involved in the regulation of pregnancy, the placenta, the uterus, and the embryo can only be reached by test compounds via the blood, at least when normal, non-invasive exposure routes are applied.

-All the tests performed on Aluminium dross for the purposes of Chemical Safety Assessment for REACH showed no effects of toxicological activity. More specifically, the following tests produced no adverse toxicological effects, either local or systemic:

1.     Acute Oral toxicity. No mortalities were observed at the highest dose and no systemic effects were observed after sacrifice and dissection of the rats.

2.     Acute Skin Irritation/Corrosion in vivo. No signs of irritation were observed on the animals.

3.     Acute Eye Irritation/Corrosion in vivo. No signs of irritation were observed on the animals.

4.     Skin sensitization: Local lymph node assay (LLNA). No sensitisation effects were observed on the animals.

5.     Bacterial reverse mutation assay and in vitro micronucleus test in mammalian cells. No effects were observed in the in vitro test suggestive of relevant effects in vivo.

-Based on the toxicokinetic data for aluminium there is a rapid elimination of absorbed percentage via urine whereas the remaining fraction is mainly stored in bones(Priest, 2004).Furthermore, on toxicological tests that were performed on aluminium dross or its constituents/degradation products (Aluminium metal, Aluminium oxide, Ammonia), no systemic effects were observed. Sub-chronic inhalation exposure studies on aluminium and aluminium oxide in concentrations of up to 75mg/m³for 6 months did not produce adverse systemic effects (see also Gross et al, 1973).Aluminium hydroxide(alumina hydrate) is an inert dust which is extensively used in pharmaceuticals, personal care products and foodstuffs, thus its safety has been verified. It is also used as an adjuvant to the diphtheria and pertussis toxoid for infant immunization. Ammonia is mainly characterised by its irritant properties to the upper respiratory tract and no systemic effects related to the reproductive system were observed in both acute and chronic toxicity studies.

-Exposure to aluminium dross can occur only in the occupational environment. Due to its handling in operations closed to the environment no relevant exposure is expected. Additionally its use takes place only in industrial settings with the material being loaded in closed metal drums (See Endpoint 13 Assessment Reports: CSR, Exposure scenarios) hence no general public exposure is expected. Relevant routes of exposure are inhalation and ingestion. Absorption through the skin is unlikely due to the low solubility of the substance's components. Furthermore, worker exposure via ingestion is considered unlikely based on the fact that the workers do not eat in proximity to where aluminium dross is handled. Proper personal protective equipment are used by the workers who handle the material in the areas where dust may be generated (See Endpoint 13 Assessment Reports: CSR, Exposure scenarios).

Granulometry testing has concluded that Aluminium dross is a coarse material, with only 37.6% of its mass passing through a sieve with mesh size 1000μm. About 30% of this fraction's mass was measured to have a particle size smaller than 100μm. In total, the inhalable fraction of the material (<100μm) consists only the 10% of its mass. This reduces significantly the exposure by inhalation to aluminium dross dust.

-Based on the above information, the substance is known to have no toxicological activity, while also no human exposure occurs. Additionally, relevant human exposure, based on toxicokinetic and other toxicological data, can be ruled out. This agrees with the specific rules for adaptation from Column 1 stated in Column 2 of Annexes VII, VIII and IX of REACH Regulation for Data requirements 8.7.1 (Reproductive Toxicity), and 8.7.2 (Developmental Toxicity). Therefore, no need to perform this test arises.

Short description of key information:
The following information is taken into account for any hazard/risk assessment
Studies of effect of aluminium dross on fertility are waived on the grounds that these effects depend entirely on systemic exposure. Systemic exposure can be ruled out owning to the negligible solubility of the compound in water and water based solutions. Systemic exposure was also not an issue in actual experiments with the compound. There is no significant systemic exposure after inhalation or dermal contact, the relevant exposure routes in the present content: Exposure scenarios, protective measures used and physical data of the compound (granulometry) deter from absorption towards systemic circulation. Furthermore, experimental data show that when this contact is possible, effects are negligible and/or local but not systemic

Effects on developmental toxicity

Description of key information

The following information is taken into account for any hazard/risk assessment
Studies of effect of aluminium dross on fertility are waived on the grounds that these effects depend entirely on systemic exposure. Systemic exposure can be ruled out owning to the negligible solubility of the compound in water and water based solutions. Systemic exposure was also not an issue in actual experiments with the compound. There is no significant systemic exposure after inhalation or dermal contact, the relevant exposure routes in the present content: Exposure scenarios, protective measures used and physical data of the compound (granulometry) deter from absorption towards systemic circulation. Furthermore, experimental data show that when this contact is possible, effects are negligible and/or local but not systemic

Additional information

See above

Justification for classification or non-classification

No classification justified because possible endpoints require systemic exposure which will be negligible after inhalation or dermal exposure. Oral exposure only occurs on purpose and is not relevant in industrial settings