Aluminium sulphate

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation

Remarks:

in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Reliable without restrictions. Well-presented study, with relevant measurement of chemical concentrations

Qualifier:

according to guideline

Guideline:

other: skin prick test

Principles of method if other than guideline:

Methods: The authors employed a novel in vivo approach to examine the possibility of using aluminum sulfate to control environmental allergens.
Fifty skin test reactive patients were simultaneously skin tested with conventional test materials and the actions of the protein/glycoprotein modifier, aluminum sulfate. Common allergens, dog, cat, dust mite, Alternaria, and cockroach were used in the study.
Toxicity tests were performed using cultured human endothelial cells (obtained from ATCC, Rockville, MD; CRL 1730) and the trypan blue dye exclusion test to evaluate the safety of using Aluminium sulphate,in human applications.
Cells were incubated for 24 h with 1:10, 1:20, or 1:30 dilutions of Aluminium sulphate, collected and examined microscopically for dye uptake. A hemocytometer was used for quantitation. Three separate tests were performed

GLP compliance:

not specified

Type of study:

other: skin prick test

Species:

human

Strain:

other:

Sex:

male/female

Details on test animals and environmental conditions:

Patient selection:
Individuals were recruited from a large private allergy practice in Louisville, KY, between 1999 and 2005. The age range was from 10 to 66 yrs. These patients had clinical symptoms of rhinitis, asthma, conjunctivitis, chronic sinusitis or a combination of 2 or more of the manifestations of Type I hypersensitivity reactions. The protocol to be used in the study was explained in detail to the patients and they were given the option of participating in the study, informed consent was granted. If their prescribed routine allergy skin test produced a high level of reactivity to one of the selected test antigens they were included in the study groups. No volunteer was compensated monetarily or otherwise for his or her participation and no funding for the study came from outside sources.

Route:

epicutaneous, open

Vehicle:

other: saline

Concentration / amount:

Aluminum sulfate, Al2(SO4)3, (Sigma/Aldrich, St. Louis) was prepared by dissolving proper aliquots in sterile water. Using the same diluent as for the allergens (normal saline), 8.75% (ASα) and 34.2% (ASβ) solutions of the chemical were prepared. Prior to use, they were filtered using a micropore filter #4, placed in sterile containers, and stored at 4°C until used in skin test.

Route:

epicutaneous, open

Vehicle:

other: saline

Concentration / amount:

Aluminum sulfate, Al2(SO4)3, (Sigma/Aldrich, St. Louis) was prepared by dissolving proper aliquots in sterile water. Using the same diluent as for the allergens (normal saline), 8.75% (ASα) and 34.2% (ASβ) solutions of the chemical were prepared. Prior to use, they were filtered using a micropore filter #4, placed in sterile containers, and stored at 4°C until used in skin test.

No. of animals per dose:

In this experiment, a group of 50 patients were used. They were selected for testing with the AS-allergen mixtures based on their level of sensitivity to routine allergy skin tests. For this purpose, only those allergens that had induced a +4 reaction (10 mm or greater) were mixed with AS for further skin testing.

Details on study design:

Patient selection
Individuals were recruited from a large private allergy practice in Louisville, KY, between 1999 and 2005. The age range was from 10 to 66 yrs. These patients had clinical symptoms of rhinitis, asthma, conjunctivitis, chronic sinusitis or a combination of 2 or more of the manifestations of Type I hypersensitivity reactions. The protocol to be used in the study was explained in detail to the patients and they were given the option of participating in the study, informed consent was granted. If their prescribed routine allergy skin test produced a high level of reactivity to one of the selected test antigens they were included in the study groups. No volunteer was compensated monetarily or otherwise for his or her participation and no funding for the study came from outside sources.

Aluminum sulfate solution preparations
Aluminum sulfate, Al2(SO4)3, (Sigma/Aldrich, St. Louis) was prepared by dissolving proper aliquots in sterile water. Using the same diluent as for the allergens (normal saline), 8.75% (ASα) and 34.2% (ASβ) solutions of the chemical were prepared. Prior to use, they were filtered using a micropore filter #4, placed in sterile containers, and stored at 4°C until used in skin test.

Toxicity testing
Toxicity tests were performed using cultured human endothelial cells (obtained from ATCC, Rockville, MD; CRL 1730) and the trypan blue dye exclusion test to evaluate the safety of using AS in human applications . Cells were incubated for 24 h with 1:10, 1:20, or 1:30 dilutions of ASβ, collected and examined microscopically for dye uptake. A hemocytometer was used for quantitation. Three separate tests were performed.

Allergens used
Initial screening of patients involved only routine inhalant skin test with the following allergens: animal danders, cockroach, dust mite, mold spores and pollens of grasses, weeds and trees prevalent in the Ohio River Valley. They were obtained from Greer Labs (Lenoir, NC) and used at a standard prick test concentration. Those patients who produced high skin reactions (when compared to the diluent control, normal saline) to cat, dog, Alternaria, dust mites, cockroach or multiples there of were selected to undergo additional skin tests with these same allergens mixed with AS. AS-allergen preparations were created by mixing 0.1 ml ASα (8.75%) to 0.9 ml of the skin test dose allergen or 0.1 ml ASβ (34.2%) to 0.9 ml of the skin test dose allergen. No precipitate was observed upon mixing of the allergen and AS. All skin reactions were read 20 min after the prick test was applied.

Skin test evaluation
The diameter of the patients' skin test responses to allergens or allergens mixed with AS were measured using skin test calipers and recorded in terms of size in mm of induration (wheal size) at the largest diameter. Clinical score: a conventional grading system of + to 4+ was also used as determined by these parameters: (+) = 3 to 5 mm wheal; (++) = 5 to 7 mm wheal; (+++) = 7 to 10 mm wheal; (++++) = 10 mm or greater wheal; erythema (E) and pseudopod (P) were also observed and recorded. P-values were determined using an unpaired two-tailed Student's t-test (< 0.05 was considered statistically significant).

Histamine
Histamine base solution (1.8 mg/ml and 50% glycerol wt/vol), obtained from Allermed Labs (SanDiego, CA), was injected intradermally alone and mixed with AS (at a concentration of 0.9% and 9.0%). Controls included 0.9% NaCl, 0.4% phenol. After 20 min, lesion diameters were measured as before using skin test calipers. In some cases, reactive sites that had previously been injected with only histamine, received a second injection with just AS. As before, responses were read 20 min later.

Sample dialysis
Lyophilized cat dander was purchased from Greer Labs (Lenoir, NC) and suspended in 100 microliters of sterile water to a concentration of 29 mg/ml. Next, 15 microliters was added to either 1 ml sterile water (sample 1) or 1 ml 9% AS (samples 2 & 3). Sample 1 was then dialyzed for 6 h against 1 liter of sterile water, sample 2 was dialyzed for 6 h against 1 liter of 9% AS, and sample 3 was dialyzed for 6 h against 1 liter of sterile water. Final allergen concentration was estimated to be approximately 50,000 BAU. Samples were then used for skin testing in three patients sensitized to cat allergen with inclusion of proper controls, sterile water as sample 4 and 9% AS solution as sample 5. The experiment was repeated using Centricon ultrafiltration devises (Millipore, 3K MW cutoff) as a different means to dialyze the samples. Dialysis was accomplished by addition of 2 ml of either 9% AS or water following complete concentration of the samples, this was repeated four times to ensure complete dialysis of the samples was accomplished.

Challenge controls:

99.9%

Positive control substance(s):

no

Remarks:

Aluminum sulfate significantly reduces the allergen-induced skin prick response. Aluminum sulfate exhibited no toxicity.

Concentration:

AS-allergen preparations were created by mixing 0.1 ml ASα (8.75%) to 0.9 ml of the skin test dose allergen or 0.1 ml ASβ (34.2%) to 0.9 ml of the skin test dose allergen. No precipitate was observed upon mixing of the allergen and AS. All skin reactions were read 20 min after the prick test was applied.

No. of animals per dose:

Fifty skin test reactive patients were simultaneously skin tested with conventional test materials and the actions of the protein/glycoprotein modifier, aluminum sulfate.
Patient selection
Individuals were recruited from a large private allergy practice in Louisville, KY, between 1999 and 2005. The age range was from 10 to 66 yrs

Positive control substance(s):

other: Aluminum sulfate exhibited no toxicity

Statistics:

Aluminum sulfate exhibited no toxicity,
Aluminum sulfate significantly reduces the allergen-induced skin prick response,
Aluminum sulfate does not block histamine effects,
Exposure to aluminum sulfate alters the allergen.

Positive control results:

Aluminium sulphate (AS) was found to significantly reduce the skin test response in sensitized patients to each of the allergens tested: dust mite, Alternaria, dog, cat, and cockroach. The exact mechanism in which aluminium sulphate (AS) produces this effect is not known. However, the results demonstrate that aluminium sulphate (AS) does not block the effects of histamine, and produces its effect without being present in the skin test sample. It appears that aluminium sulphate (AS) alters the allergen, changing its epitopes, thus reducing the ability of specific IgE to bind and ultimately mast cell degranulation.
Aluminium sulphate (AS) does not stain, is cheap, nontoxic, is stable in solution, and appears to have long acting affects, making it a great candidate for use as an environmental control agent.

Reading:

rechallenge

Hours after challenge:

24

Group:

negative control

Dose level:

Aluminium sulphate (AS)-allergen preparations were created by mixing 0.1 ml ASα (8.75%) to 0.9 ml of the skin test dose allergen or 0.1 ml ASβ (34.2%) to 0.9 ml of the skin test dose allergen.

No. with + reactions:

50

Total no. in group:

5

Clinical observations:

Aluminum sulfate exhibited no toxicity, Aluminum sulfate significantly reduces the allergen-induced skin prick response, Aluminum sulfate does not block histamine effects, Exposure to aluminum sulfate alters the allergen

Remarks on result:

other: see Remark

Remarks:

Reading: rechallenge. . Hours after challenge: 24.0. Group: negative control. Dose level: Aluminium sulphate (AS)-allergen preparations were created by mixing 0.1 ml ASα (8.75%) to 0.9 ml of the skin test dose allergen or 0.1 ml ASβ (34.2%) to 0.9 ml of the skin test dose allergen.. No with. + reactions: 50.0. Total no. in groups: 5.0. Clinical observations: Aluminum sulfate exhibited no toxicity, Aluminum sulfate significantly reduces the allergen-induced skin prick response, Aluminum sulfate does not block histamine effects, Exposure to aluminum sulfate alters the allergen.

Fig.1 (see attachments) 

Selected patients were skin tested with allergens mixed with AS. Controls included allergens alone and saline. Means and standard deviations, as well as P-values, of data (clinical scores, see Methods) collected from the 50 patients are presented. P-values were determined using an unpaired two-tailed Student's t-test. A P-value of < 0.05 was considered statistically significant. Notice that AS markedly reduced skin test reactions to the allergens tested.

Fig.2 (see attachments) 

Wheal and flare responses in a patient skin tested with the cat allergen and cat allergen mixed with AS, as in Figure 1. Histamine and saline were included as controls. Reactions were read with no testing (A), 5 min (B), 15 min (C), and 30 min (D). Within each panel, skin prick responses are shown to: histamine (1), saline (2), 10% saline + 90% cat allergen (3), cat allergen (4), and 10% ASβ+ 90% cat allergen (5). Wheals were measure by the aid of skin test calipers.

Fig.3 (see attachments)  

Aluminum sulfate does not block histamine. Skin reactions at 15 min are shown in panel (A). Skin reactions at 30 min are shown in panel (B). Within panels A and B, skin prick responses are shown to: saline (1), histamine (2), 0.9% AS (3), 9.0% AS (4), 0.9% AS + histamine (1.8 mg/ml) mixed at 1:10 (AS:histamine) (5), and 9.0% AS + histamine (1.8 mg/ml) mixed at 1:10 (AS:histamine) (6). Skin reaction to 0.1 cc AS ID at 15 min is shown in panel (C) (site 7). Skin reaction 15 min following overlay of site 7 in panel C with histamine (1.8 mg/ml) is shown in panel (D). Notice that AS did not inhibit the histamine induced skin reaction

Fig.4 (see attachments) 

Exposure to aluminum sulfate alters the allergen. Skin test results of three patients after 30 min are shown. Sample 1 contains cat allergen and water which was dialyzed against water and thus acts as a positive control. Sample 2 includes cat allergen and AS which was dialyzed against AS, thus the test sample contains AS. Sample 3 is cat allergen and AS which was dialyzed against water, therefore the test sample does not contain AS. Water and AS controls are also shown (samples 4 and 5 respectively). Representative photograph (patient 3) of skin test response after 30 min is also shown.

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Aluminium sulphate (AS) was found to significantly reduce the skin test response in sensitized patients to each of the allergens tested: dust mite, Alternaria, dog, cat, and cockroach. The exact mechanism in which aluminium sulphate (AS) produces this effect is not known. However, the results demonstrate that aluminium sulphate (AS) does not block the effects of histamine, and produces its effect without being present in the skin test sample. It appears that aluminium sulphate (AS) alters the allergen, changing its epitopes, thus reducing the ability of specific IgE to bind and ultimately mast cell degranulation.
Aluminium sulphate (AS) does not stain, is cheap, nontoxic, is stable in solution, and appears to have long acting affects, making it a great candidate for use as an environmental control agent.

Executive summary:

Background Avoidance of allergens is still recommended as the first and best way to prevent allergic illnesses and their comorbid diseases. Despite a variety of attempts there has been very limited success in the area of environmental control of allergic disease. Our objective was to identify a non-invasive, non-pharmacological method to reduce indoor allergen loads in atopic persons' homes and public environments. We employed a novelin vivoapproach to examine the possibility of using aluminum sulfate to control environmental allergens. Methods Fifty skin test reactive patients were simultaneously skin tested with conventional test materials and the actions of the protein/glycoprotein modifier, aluminum sulfate. Common allergens, dog, cat, dust mite, Alternaria, and cockroach were used in the study. Results Skin test reactivity was significantly reduced by the modifier aluminum sulfate. Our studies demonstrate that the effects of histamine were not affected by the presence of aluminum sulfate. In fact, skin test reactivity was reduced independent of whether aluminum sulfate was present in the allergen test material or removed prior to testing, indicating that the allergens had in some way been inactivated. Conclusion Aluminum sulfate was found to reduce the in vivo allergic reaction cascade induced by skin testing with common allergens. The exact mechanism is not clear but appears to involve the alteration of IgE-binding epitopes on the allergen. Our results indicate that it may be possible to diminish the allergenicity of an environment by application of the active agent aluminum sulfate, thus producing environmental control without complete removal of the allergen.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Skin sensitisation

No evidence of sensitisation in the study of of C Steven Smith et al 2006.The results demonstrate that aluminium sulphate (AS) does not block the effects of histamine, and produces its effect without being present in the skin test sample. It appears that aluminium sulphate (AS) alters the allergen, changing its epitopes, thus reducing the ability of specific IgE to bind and ultimately mast cell degranulation. Aluminium sulphate (AS) does not stain, is cheap, nont oxic, is stable in solution, and appears to have long acting affects, making it a great candidate for use as an environmental control agent.

 

Synopsis

Not sensitising

Migrated from Short description of key information:
No evidence of skin sensitisation. It is concluded that the substance Aluminum sulphate does not meet the criteria to be classified for human health hazards for skin sensitisation - local effect: skin sensitisation.

Respiratory sensitisation

Link to relevant study records

Reference

Endpoint:

respiratory sensitisation: in vivo

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Study period:

2008

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Basic data given

Qualifier:

no guideline available

Principles of method if other than guideline:

Examination of the absolute and relative numbers of different cell types and specific biochemical parameters in fluid obtained from bronchoalveolar lavage of animal lungs (BALF) following either intratracheal or inhalation exposure to a substance can provide information on the nature of the reaction of the tissue, i.e the mechanism of action. This information is useful to support and interpret histopathological observations and/or external observations of respiratory symptoms or changes in lung function. In this study, histopathology and BALF analyses were done in the the presence and absence of ovalbumin, a known inducer of eosinophilic inflammation, in order to provide further information on the nature of the mechanism of action (allergenic versus non-specific irritative).

GLP compliance:

no

Species:

mouse

Strain:

ICR

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Japan, Inc. (Kanagawa, Japan)
- Age at study initiation: 5 weeks at arrival; 6 weeks at testing
- Weight at study initiation: 307-315 g
- Housing: Plastic cages placed in a “conventional” room. Bedding with soft wood chips not otherwise specified.
- Diet: commercial diet CE-2 obtained from CLEA Japan Inc., Tokyo, Japan.
- Water: ad libitum
- Acclimation period: 1 week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 23 °C
- Humidity (%): 55-70%
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): Artificial light 12 hours daily from 6 a.m. to 6 p.m.

Justification of species and strain: ICR mice were chosen based on the results of an earlier study (Ichinose T et al., 2003; Toxicol Appl Pharmacol 187: 29-37) that showed that this species is “moderately” responsive to airway inflammation on exposure to OVA by intratracheal instillation (IT).

Route of induction exposure:

other: Intratracheal instillation

Route of challenge exposure:

other: not applicable

Vehicle:

other: Normal saline

Concentration:

Negative vehicle control (saline),
OVA alone,
Asian SD alone,
Arizona SD alone,
SiO2 alone,
Al2O3 alone,
Asian SD + OVA,
Arizona SD + OVA,
SiO2 + OVA,
Al2O3 + OVA.

Concentration: 0.1 mg per mouse

Deposition efficiencies were calculated using a tidal volume of 0.15 mL/mouse and a breathing rate of 200 breaths per minute. 0.1 mg/mouse was reported to be 111 times the weekly amount of particulate matter that would be deposited in the alveoli assuming 3% deposition (based on the ICRP model at 5.5 micron particle size) at an exposure level of 0.1 mg/m3.

No. of animals per dose:

16 animals/group
- 8 animals used for pathology and 8 animals for BALF analyses.

Details on study design:

Preparation of Test Solution:
In the absence of OVA, 5 mg of particulate was suspended in 2.5 or 5 mL of vehicle and sonicated for 5 minutes while being cooled (temperature not specified)
For the combined OVA and particulate exposure, the OVA (100µg) was dissolved in 10 mL or 5 mL of saline vehicle. 2.5 mL of the OVA solution was then mixed with 2.5 mL of the particle suspension.

Administration of Test Solution:
Volume: 0.1 mL
Method: The suspension was intratracheally administered under anaesthesia (4% halothane, Takeda Chemical, Osaka, Japan) using a polyethylene tube.
The animals were dosed 4 times in total. The interval between doses was 2 weeks.

Further Study details:
The animals were killed by exsanguination one day after the last intratracheal instillation when anaesthetised using an i.p. injection of pentobarbital. At this time, the animals were approximately 12 weeks of age.

Observations:
Pathology of Lung Tissue:
Pathologic examinations were done on the lung tissue from 8 out of 16 mice/group. The lungs were fixed with 10% neutral phosphate-buffered formalin, stained with haematoxylin and eosin (H&E) to assess infiltration of eosinophils and lymphocytes and also, to assess proliferation of goblet cells, periodic acid-shiff (PAS). The evaluation was done by two pathologists independently.

Bronchoalveolar fluid (BALF) analyses:
Cell counts:
The BALF of the remaining 8 mice was evaluated for cell counts. Slides were prepared using a Cytopsin (Sakura Co., Ltd., Tokyo, Japan) and were stained with Diff-Quik. 300 cells were counted.

Levels of cytokines:
The cytokines interleukin-5 (IL-5), IL-12, interferon-gamma (IFN-γ), tumour necrosis factor-alpha (TNF-α), macrophage inflammatory protein-1alpha (MIP-1α), IL-13, and eotaxin were measured using ELISA.

Levels of lactate dehydrogenase (LDH):
Measured using a lactate dehydrogenase C II-Test Wako from Wako Chemicals Ltd. (Osaka, Japan).

Antigen (OVA)-specific and total IgE and IgG1 antibodies:
The antibodies were measured using commercial ELISA kits.

Statistical Analyses:
Group differences were assessed using ANOVA and the Fisher’s projected least significant differences (P/SD) test.

Challenge controls:

Not applicable.

Positive control substance(s):

none

Negative control substance(s):

not specified

Results:

Pathology of Lung Tissue:
Al2O3:
The animals treated with aluminium oxide did not show a significantly increased proliferation of goblet cells or infiltration of lymphocytes when compared with the saline control.

OVA + Al2O3:
Lymphocyte infiltration was higher in the OVA+Al2O3 group compared with the control (p<0.001), and also when compared with OVA alone (p<0.01) and with Al2O3 alone (p<0.001).

Eosinophil infiltration was higher in the OVA+Al2O3 group compared with the control (p<0.01) and also OVA+Al2O3 compared with Al2O3 alone (p<0.01).

Goblet cell proliferation was higher in the OVA+Al2O3 group compared with the control (p<0.001), OVA+Al2O3 compared with OVA alone (p<0.05) and also when compared with Al2O3 alone (p<0.001).

Among the groups exposed to the particulates alone, the greatest changes were observed in the SiO2-treated group. Among the groups treated with OVA+particulates, the greatest changes were observed in the OVA+SiO2 group followed by the OVA+Arizona SD group, the OVA+Asian SD group and last the OVA+Al2O3 group.

Bronchoalveolar Lavage Fluid (BALF):
Cell counts
Total cells:
Among the groups exposed to particulates alone, only the SiO2-treated group had levels significantly greater than the control.
In the combined exposure groups, OVA+Asian SD, OVA+Arizona SD, and OVA+SiO2 had levels greater than the control (p<0.001). Total cells in the OVA + Al2O3 group were also significantly greater than the control but not to the same extent (p<0.05). No groups had cell counts greater than that observed in the group with OVA alone. The highest numbers were observed in the OVA+SiO2 group.

Macrophages:
Among the groups exposed to particulates alone, only Arizona SD and SiO2 caused significant increases in macrophages compared with the control (p<0.01 and p<0.001, respectively).
Among the combined exposure groups, OVA + Asian SD, OVA + Arizona SD, and OVA + SiO2 showed levels greater than the control. Numbers of macrophages in the OVA + Al2O3 group were greater than the control but not to the same extent (p<0.01). Only OVA+Arizona SD and OVA+SiO2 had greater numbers of macrophages than the OVA alone group (p<0.05 and p<0.001, respectively).

Eosinophils:
Particulates alone:
No effects observed.
Combined exposures:
OVA+Al2O3Numbers of eosinophils in the OVA+Asian SD (p<0.05), the OVA+Arizona SD (p<0.001) and the OVA+SiO2 (p<0.001) were greater than in the controls. None showed levels greater than OVA alone.

Neutrophils:
Particulates alone:
The SiO2 group was significantly greater than the controls (p<0.001)

Combined exposures:
OVA+Al2O3
Lymphocytes:
Levels in the Arizona SD group were significantly greater than the controls (p<0.01).
OVA+Asian SD (p<0.05) and OVA+Arizona SD (p<0.001) were significantly greater than the OVA only group.

Cytokines
IL-5
Significant elevations were observed for OVA+Arizona SD and OVA+SiO2 compared to the control and compared to OVA alone.

IL-6
A significant elevation was observed for OVA+SiO2 compared to OVA alone.

IL-12
The SiO2 group had significantly higher levels than the control (p<0.001). The OVA+SiO2 group had significantly higher levels than the control (p<0.001), the OVA alone group (p<0.001), and the SiO2 alone group (p<0.001). Levels in the OVA+Arizona SD group were marginally significantly greater than the control group (p<0.05).

IL-13
The OVA+SiO2 group had significantly higher levels than the control (p<0.001), OVA alone (p<0.001), and SiO2 alone groups.

IFN-γ
Asian SD alone (p<0.01), Arizona SD alone (p<0.01), SiO2 alone (p<0.01) and Al2O3 alone (p<0.05) had significantly higher levels than the control.

TNF-α
The Asian SD group (p<0.01), the SiO2 group (p<0.01) and the Al2O3 group (p<0.05) had significantly higher levels than the control. In the combined exposures, OVA+Asian SD and OVA+Arizona SD had higher levels than the controls. None of the particulate-treated groups had levels significantly higher than the OVA alone group.

Levels of lactate dehydrogenase (LDH):
Control: 8.48±1.38 IU/L
Asian SD: 5.56±0.26 IU/L
Arizona SD: 8.19±1.05 IU/L
SiO2: 9.99±0.75 IU/L
Al2O3: 6.17±0.77 IU/L
OVA: 5.09±0.67 IU/L
OVA+Asian SD: 5.98±0.65 IU/L
OVA+Arizona SD: 7.35±1.11 IU/L
OVA+SiO2: 31.18±8.97 IU/L
OVA+Al2O3: 6.37±0.42 IU/L

For the chemokine eotaxin, significant elevations were observed only in the OVA+SiO2 group. KC (keratinocyte chemoattractant) was significantly elevated relative to the control in the Arizona SD (p<0.01) and SiO2 (p<0.001) groups. In the combined exposure groups, the OVA+Arizona SD and OVA+SiO2 groups were significantly elevated relative to both the controls and the OVA alone groups. Levels of monocyte chemotactic protein-3 (MCP-3) in the OVA+Arizona SD and OVA+SiO2 groups were also significantly elevated relative to the control and the OVA alone group. Macrophage inflammatory protein-1α was significantly elevated in the Arizona SD and SiO2 groups relative to the controls and in the OVA+SiO2 group relative to the OVA alone group. OVA+Asian SD, OVA+Arizona SD and OVA+SiO2 had levels significantly greater than the control.

Antigen (OVA)-specific and total IgE and IgG1 antibodies:
Serum levels of OVA specific IgG1 antibodies were significantly elevated relative to levels in the OVA group alone in animals treated with OVA+Arizona SD and OVA+SiO2 (p<0.001). No OVA-specific IgE antibodies were detected. Levels of total IgE in serum in the particulate-treated groups did not differ significantly from levels in the group treated with OVA alone.

Positive control results:

Not applicable.

Negative control results:

Not applicable.

Interpretation of results:

not sensitising

Conclusions:

When co-administered with OVA, all the tested materials showed an increase in eosinophils on H&E stained slides (OVA+SiO2>OVA+Arizona SD>OVA+Asian SD>OVA+Al2O3). Considering the results for Al2O3, specifically, in BALF, Al2O3 alone did not lead to significant increases in total cells, macrophages, eosinophils, neutrophils or lymphocytes. When Al2O3 was administered with OVA, small but statistically significant increases in total cells (p<0.05), macrophages (p<0.01) and lymphocytes (p<0.05) were observed relative to the control but not relative to the OVA alone group. Significant (p<0.05) increases in IFN-γ and TNF-α relative to the saline control were observed in BALF of Al2O3 treated animals. IL-5, IL-6, IL-12 and IL-13 did not show significant increases in the Al2O3-treated animals. In exposures combined with OVA, the only significantly elevated cytokine was IFN-γ.

Overall, the results from the study showed that allergic inflammatory effects of atmospheric dusts are likely due to SiO2. Al2O3 was the least inflammatory material tested and led to only weak effects on the mouse lung.

Executive summary:

Ichinose et al. (2008) studied allergic inflammation after intratracheal instillation of Asian sand dust,sand dust, amorphous silica and Al2O3in 6-week old male ICR mice. Four instillations were performed at 2-week intervals. There were ten groups of animals (n=16 in each). One of these groups received Al2O3(particle size 1 ~ 5 µm), a dose of 0.1 mg suspended in saline. The control group received saline only (0.1 mL). The animals were killed one day after the last instillation. Eight out of 16 animals in each group were used for pathologic examination. The lung samples were stained with haematoxylin and eosin to evaluate the degree of infiltration of eosinophils or lymphocytes in the airways, and with periodic acid-shiff to evaluate the degree of proliferation of goblet cells in the bronchial epithelium. The other 8 mice were used for examination of free cell counts (total and differential), determination of levels of lactate dehydrogenase (LDH), cytokines (Interleukins – IL-5, IL-6, IL-12, IL-13, interferon-IFN- g and tumor necrosis factor- TNF- a ) and chemokines in bronchoalveolar lavage fluids (BALF), and also total IgE in serum using enzyme-linked immunosorbent assays (ELISA). In the group of mice exposed to Al2O3, the levels of eosinophil and lymphocyte infiltration in the submucosa and proliferation of goblet cells in the airways, the level of LDH, chemokines and interleukins, number of cells in BALF and the level of IgE in serum were not significantly different from those in the control mice. The results suggest that intratracheal administration of Al2O3does not produce allergic inflammatory effects in the lungs of mice.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Respiratory sensitisation.

Ichinose et al. (2008) studied allergic inflammation after intratracheal instillation of Asian sand dust,sand dust, amorphous silica and Al2O3in 6-week old male ICR mice. Four instillations were performed at 2-week intervals. There were ten groups of animals (n=16 in each). One of these groups received Al2O3(particle size 1 ~ 5 µm), a dose of 0.1 mg suspended in saline. The control group received saline only (0.1 mL). The animals were killed one day after the last instillation. Eight out of 16 animals in each group were used for pathologic examination. The lung samples were stained with haematoxylin and eosin to evaluate the degree of infiltration of eosinophils or lymphocytes in the airways, and with periodic acid-shiff to evaluate the degree of proliferation of goblet cells in the bronchial epithelium. The other 8 mice were used for examination of free cell counts (total and differential), determination of levels of lactate dehydrogenase (LDH), cytokines (Interleukins – IL-5, IL-6, IL-12, IL-13, interferon-IFN- g and tumor necrosis factor- TNF- a ) and chemokines in bronchoalveolar lavage fluids (BALF), and also total IgE in serum using enzyme-linked immunosorbent assays (ELISA). In the group of mice exposed to Al2O3, the levels of eosinophil and lymphocyte infiltration in the submucosa and proliferation of goblet cells in the airways, the level of LDH, chemokines and interleukins, number of cells in BALF and the level of IgE in serum were not significantly different from those in the control mice.

Based on the results of the study ofIchinose et al.2008 it was concluded that the test compound Aluminum sulfate,(the result was read across from aluminium oxide) does not produce allergic inflammatory effects in the lungs of mice.

Synopsis

Not Sensitising

Migrated from Short description of key information:
No evidence of respiratory sensitisation. It is concluded that the substance Aluminum sulphate does not meet the criteria to be classified for human health hazards for Inhalation - local effect: respiratory sensitisation.

Justification for classification or non-classification

Based on the hazard assessment of aluminium sulphate in section 2.1 and 2.2.in IUCLID 5.4., available data for the substance and following the “Guidance on Information Requirement and Chemical Safety Assessment R.8. Characterisation of dose [concentration]- response for human health” andaccording to the criteria described in Directive 67/548 and in the CLP Regulation:

 

 

Directive 67/548	Respiratory Sensitisation Xn R42 May cause sensitization by inhalation Respiratory Irritation Xi R37 irritating to respiratory system SkinSensitisation  R43 May cause sensitization by skin contact
CLP	H317 Skin Sens. 1 May cause an allergic skin reaction Respiratory Sensitisation  H334 Resp. Sens. 1 May cause allergy or asthma symptoms or breath-ing difficulties if inhaled Respiratory Irritation H335 STOT SE 3 May cause respiratory irritation SkinSensitisation  H317 Skin Sens. 1 May cause an allergic skin reaction

 

It is concluded that the substance aluminium sulphate does not meet the criteria to be classified for human health hazards for Inhalation - local effect: respiratory sensitisation and  Skin Sensitisation 

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