HDI oligomers, biuret

Exposure related observations in humans: other data

Administrative data

Endpoint:

exposure-related observations in humans: other data

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: reliable experimental method and documentation

Data source

Reference

Reference Type:

publication

Title:

Biomonitoring and examinations on the kinetics of isocyanates amongst spray painters

Author:

Yu F et. al.

Year:

2005

Bibliographic source:

Zbl Arbeitsmed 55: 23-25

Materials and methods

Type of study / information:

Monitoring of occupational exposure

Endpoint addressed:

other: Biomonituring

Principles of method if other than guideline:

Development of method, no guideline available

Test material

Test material information

Constituent 1

Reference substance name:

Reference substance 001

Cas Number:

28182-81-2

Molecular formula:

Unspecified (UVCB substance)

Details on test material:

HDI, oligomers (biuret type) as an ingredient of hardeners of 2-component paints. The name of the substances, the workers were exposed to, are not specified.

Method

Details on study design:

From different working groups urine was sampled prior and after isocyanate-exposure, for instance at the end of the shift.
Samples were treated with acid, and the so released diamines (= biomarker) were converted into the corresponding amids or into the carbamates. These derivates could be quantified via GC-MS. Results were given as µg amine per gram creatinine (µg/g crea).

Exposure assessment:

measured

Results and discussion

Any other information on results incl. tables

HDI-Biuret:

air concentrations: 5ppb

no data concerning HDI-biuret composition.

3 human workers

The initial half-life was identified as 1.3 -3.9 h.

Peak concentration was identified at the end of exposure (20 -31 µg/g crea).

24h after exposure no HDA can be measured in urine.

HDI-Isocyanurate:

unknown air concentration

It is stated, that these workers were exposed to HDI Trimer (no data concerning source).

5 Human workers, exposition 8h,

The half life for the biomarker for HDI Trimer was determined to be 4.9 -8.6 h. The maximum concentration was achieved 5h after the end of exposure. 24h after exposure the biomarker could still be detected in urine.

The HDI isocyanurate trimer biomarker apparently has a longer half life, compared to other aliphatic diisocyanate biomarkers (biomarker of HDI monomer, HDI biuret or IPDI).

28 Spray painters:

The biomarker HDA could be detected in urine in 54% with a concentration between 0.5 to 380 µg/g crea. The mean was 63 +/-100.5 µg/g crea.

62 office workers:

only in one sample the biomarker could be detected.

14 Polishers:

36% were detected as HDA biomarker positive (concentration between 4 to 130 µg/g crea, mean: 48.6 +/-49.5 µg/g crea), corresponding to the high content of HDI/hexamethylene diamine detected in the dust of the working places (242 µg/g dust).

-> The composition of the Varnish is not given for the above cited spray painters and polishers.

It was not investigated during the study weather the route of absorption was inhalative, despite respiratory protective equipment, or dermal.

Applicant's summary and conclusion

Executive summary:

A biomarker study of the exposure with HDI Trimer revealed a half life for the biomarker for HDI Trimer (biuret) of 1.3 - 3.9 h. The maximum concentration of the biomarker was measured at the end of exposure (5ppb). 24 h after exposure the biomarker could not be detected in urine.

Unfortunately no details on test substance composititon were indicated in the report.