Registration Dossier

Toxicological information

Epidemiological data

Currently viewing:

Administrative data

Endpoint:
epidemiological data
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Conducted to a reasonable scientific standard.

Data source

Reference
Reference Type:
publication
Title:
Are Current Biomarkers Suitable for the Assessment of Manganese Exposure in Individual Workers
Author:
Apostoli P, Lucchini R & Alessio L
Year:
2000
Bibliographic source:
American Journal of Industrial Medicine, 37: 283-290

Materials and methods

Study type:
cross sectional study
Endpoint addressed:
neurotoxicity
Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Environmental and biological monitoring (blood and urine) of 94 employees in a ferroalloy production exposed to Mn oxides (MnO2 and Mn3O4). Results compared to control group not exposed to Mn.
GLP compliance:
no

Test material

Constituent 1
Chemical structure
Reference substance name:
Trimanganese tetraoxide
EC Number:
215-266-5
EC Name:
Trimanganese tetraoxide
Cas Number:
1317-35-7
Molecular formula:
Mn3O4
IUPAC Name:
dimanganese(3+) manganese(2+) tetraoxidandiide

Method

Details on study design:
METHOD OF DATA COLLECTION
- Type: Clinical tests
- Details: Venous blood sample of 5 ml and a spot urine sample collected at the end of the shift.

STUDY POPULATION
- Selection criteria: exposed to Mn oxides or not during typical working shift
- Total number of subjects participating in study:
- Sex/age/race: male, age = 40.2 ± 8.3 years

COMPARISON POPULATION
- Type:Control or reference group
- Details: Maintenance workers with comparable habits but no Mn exposure


HEALTH EFFECTS STUDIED
- Disease(s): not reported

Exposure assessment:
measured

Results and discussion

Results:
FINDINGS
Urinary Mn (MnU) concentrations in the exposed group exhibited a five-fold increase over the controls. Blood Mn (MnB) levels were found to be twice as high in the exposed than in the controls.

Significant differences were observed between all three subgroups and the controls for MnU and MnB levels. Significant differences were also observed between all the three subgroups considered.

Confounding factors:
Smoke, alcohol, tea and coffee consumers. MnO2 in same facility.
Strengths and weaknesses:
Not reported

Any other information on results incl. tables

TABLE 1: Mean MnB Values (in µg/L) in the different Subgroups Based on MnA Levels: F-value: 37.94, P < 0.0001

Subgroup

N

Mean MnB

S.D.

Low exposure

34

8.65

3.18

Mid exposure

29

10.93

3.25

High exposure

31

11.39

4.61

Controls

89

5.99

1.73

Table 2: Mean MnU Values (in µg/L) in the Different Subgroups Based on MnA Levels: F-value: 46.26, P < 0.0001

Subgroup

N

Mean MnU

S.D.

Low exposure

34

3.12

1.48

Mid exposure

29

4.79

2.87

High exposure

31

7.04

4.72

Controls

89

1.19

1.41

Applicant's summary and conclusion

Conclusions:
These results confirm that MnB and MnU can discriminate groups of occupationally exposed workers from groups of none exposed subjects. MnB is also related to the intensity of external exposure on a linear relationship, but given a high variability, it is not suitable for individual biological monitoring. Therefore, further research should focus on more accurate biomarkers of Mn exposure.