Tetrahydro-4-methylphthalic anhydride

Exposure related observations in humans: other data

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)

Cross-reference

Reason / purpose for cross-reference:

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 on guideline. For details on method please refer to IUCLID5 dossier.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Tetrahydromethylphthalic anhydride

EC Number:

234-290-7

EC Name:

Tetrahydromethylphthalic anhydride

Cas Number:

11070-44-3

IUPAC Name:

3a-methyl-3a,4,5,6-tetrahydro-2-benzofuran-1,3-dione

Details on test material:

- Name of test material (as cited in study report): MTHPA

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.