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Exposure related observations in humans: other data

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Administrative data

Endpoint:
exposure-related observations in humans: other data
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Information published in peer reveiwed journal
Cross-reference
Reason / purpose:
reference to same study

Data source

Reference
Reference Type:
publication
Title:
Exposure assessment and sensitization in workers exposed to organic acid anhydrides
Author:
Drexler, H. et.al.
Year:
2000
Bibliographic source:
Int. Arch. Environ. Health, (2000) 73 228-234

Materials and methods

Type of study / information:
Biomonitoring (Human urine)
Endpoint addressed:
respiratory sensitisation
Test guideline
Qualifier:
no guideline available
Principles of method if other than guideline:
No information
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): MTHPA
- Molecular formula (if other than submission substance): C9 H10 O3
- Molecular weight (if other than submission substance): 166.18
- Smiles notation (if other than submission substance): O=C(OC(=O)C1CC=C(C2)C)C12
- InChl (if other than submission substance): 1/C9H10O3/c1-5-2-3-6-7(4-5)9(11)12-8(6)10/h2,6-7H,3-4H2,1H3
- Structural formula attached as image file (if other than submission substance): see Fig. (11070-44-3 structure.jpg)

Method

Ethical approval:
not specified
Details on study design:
no details given
Exposure assessment:
measured
Details on exposure:
TYPE OF EXPOSURE: inhalation at the factory
TYPE OF EXPOSURE MEASUREMENT: Biomonitoring (urine)

Results and discussion

Results:
Two hundred and nineteen workers form three plant exposed  tetrahydromethyl-1,3-isobenzofuranedione (MTHPA) used as a hardener in an  epoxy resin system were reported. The exposure assessment included stationary and ambient air monitoring and biological monitoring  (metabolites in urine). In plant A 20, in plant B 86 and in plant C 113 workers were examined by a physician. The ambient air concentration of MTHPA were 37.2 and 58.5  ug/m3 in plant A (n=2), ranged from <0.5-26.2 in plant B (n=5) and from  2.1-57.9 in plant C with stationary collecting, and from 8-45 (n=6), from  <4.7-35.7 (n=3), and from 2-37.8 (n=3) with personal air collection. The  metabolites of MTHPA in urine (in nmol/nmol creatinine) ranged from  5.7-645 in plant A, from <1-213 in plant B and from 0.1-830 in plant C.  The prevalence of sensitization was 35% in plant A, 21% in plant B and  29% in plant C. Comparing the prevalence of sensitization and the results  of biological monitoring, between the three plants, it is found that  sensitization increased with increasing exposure. Therefore, biological  monitoring is a useful tool in the exposure assessment of MTHPA.

Applicant's summary and conclusion

Conclusions:
Comparing the prevalence of sensitization and the results  of biological monitoring, between the three plants, it is found that sensitization increased with increasing exposure. Therefore, biological  monitoring is a useful tool in the exposure assessment of MTHPA.
Executive summary:

Two hundred and nineteen workers form three plant exposed tetrahydromethylphthalic anhydride (MTHPA) used as a hardener in an epoxy resin system were reported. The exposure assessment included stationary and ambient air monitoring and biological monitoring (metabolites in urine).
In plant A 20, in plant B 86 and in plant C 113 workers were examined by a physician. The ambient air concentration of MTHPA were 37.2 and 58.5 ug/m3 in plant A (n=2), ranged from <0.5-26.2 in plant B (n=5) and from 2.1-57.9 in plant C with stationary collecting, and from 8-45 (n=6), from <4.7-35.7 (n=3), and from 2-37.8 (n=3) with personal air collection. The metabolites of MTHPA in urine (in nmol/nmol creatinine) ranged from 5.7-645 in plant A, from <1-213 in plant B and from 0.1-830 in plant C. The prevalence of sensitization was 35% in plant A, 21% in plant B and 29% in plant C. Comparing the prevalence of sensitization and the results of biological monitoring, between the three plants, it is found that sensitization increased with increasing exposure. Therefore, biological monitoring is a useful tool in the exposure assessment of MTHPA.