Handbook of Solvents - George Wypych - ChemTech - Ventech!

1248 Tilman Hahn, Konrad Botzenhart, Fritz Schweinsberg, Gerhard Volland
18.3.5 METHODS FOR THE EXAMINATION OF SOLVENTS IN PAINTS AND
VARNISHES
18.3.5.1 Environmental monitoring
There are several test procedures generally used in Europe. Procedures are still being developed
to determine the presence of solvents in paints and varnishes.
18.3.5.1.1 Solvents in products
Officially approved test procedures are:
• Gravimetry: Determination of volatile organic compounds (DIN ISO 11 890-1 7 -
VOCs > 15 %).
• Gas chromatography: Determination of volatile organic compounds (DIN ISO 11
890-2 7 - VOCs 0,1 % -15 %).
18.3.5.1.2 Emission of solvents
Test chamber 7,92,93 (volume 1 m 3 , defined conditions: temperature, humidity, air changing
rates, air velocity). This is usually carried out 3 days after application of paints or varnishes
by placing the products into a test chamber. The test series starts with sampling emissions of
the products on defined absorption materials (Tenax, charcoal filters, activated charcoal),
reconditioning and finally identification and classification of VOCs with gas chromatography.
The test methods are repeated after 14 and 28 days. These test criteria permit determination
of the behavior of emissions from finished products under defined conditions.
Emission test cells. 7,92,93 The product under investigation is hermetically sealed into
the emission test cells. The emitted compounds are sampled by absorption materials and analyzed.
This method can be used under laboratory conditions or in situ.
18.3.5.2 Biological monitoring of solvents in human body fluids
18.3.5.2.1 Solvents and metabolites in human body fluids and tissues
The biological monitoring of solvents emitted from paints or varnishes on humans is not
well developed. In two studies, 94,95 solvents from paints and varnishes were determined in
blood, urine and internal breath. Blood and urine analysis is less sensitive than internal
breath measurements. This was carried out in a study on exposure to paints in aircraft maintenance.
94
Kramer et al. 95 found xylenes during paint production and paint-spraying in ambient
air and in the blood and urine of workers. Threshold limit values (TLV) and biological exposure
indices (BEI) were not exceeded. 22,23
18.3.5.2.2 Biomarkers
Even low air concentrations of solvents emitted from paints have an influence on the human
organism, e.g. the induction of hepatic enzymes. This effect was shown in workers exposed
to butyl glycol from paints in an electrophoresis painting plant where the exposure value
was shown to be less than 0.3 times of the average limit. In these cases D-glucaric acid in
urine, which reflects the D-glucarid acid enzyme pathway, was increased. 96
In some studies the genetic effects on paint industry workers could not be detected
when chromosomal aberrations and sister chromatid exchanges were studied. 86,87 In other
studies 94,95 it was shown that the frequency of micronuclei and sister chromatid exchanges
increased.