Formaldehyde Concentration Contained In The Paints For Auto-Vehicle

Sangjun CHOI, Catholic University of Daegu, South Korea
CHA W. 1 , SHIN J. 2 , CHOI B. 2

1 Department of Occupational Health, Catholic University of Daegu, Gyeongsangbukdo, Korea
2 Occupational Lung Diseases Institute, Korea Workers’ Compensation and Welfare Service, Incheon, Korea

This study was conducted to evaluate the formaldehyde concentrations in paints for auto-vehicle. A total of 21 paints for auto-vehicle, including nine oil-based paints and 12 water-based paints, were collected from 2 manufacturers in South Korea. Oil-based paints and water-based paints were diluted with toluene and de-ionized water, respectively. The DNPH derivative in the 2, 4-DNPH cartridge adsorbed diluted solution of paint was analyzed using high performance liquid chromatography. Airborne concentrations from paints were measured in two conditions of temperatures, 20 ℃ and 50 ℃, similar to painting booth and exit of dry oven in auto-vehicle manufacturing company. Emission ratio (ER) was calculated as a ratio between the airborne mass (mg) of formaldehyde and the mass (g) of paint used in experiment. A total number of 12 paints (an oil-based paint, 11 water-based paints) among 21 paints contained formaldehyde from 0.3% (wt/wt) to 1.25%. However, no paints provided the information of formaldehyde as an ingredient in material safety data sheet (MSDS). One oil-based paint with 0.3% of formaldehyde contained melamine-formaldehyde resin. The average formaldehyde contents of 0.74% in water-based paints showed significantly higher than 0.3% of oil-based paint (p<0.05). Airborne concentrations of formaldehyde ranged from 0.22 ppm to 6.72 ppm. For experiment condition, the average formaldehyde concentration, 2.76 ppm, measured in 50 ℃ showed significantly higher than 0.43 ppm of 20 ℃ (p<0.05). ER of formaldehyde ranged from 0.04 mg/g to 1.07 mg/g and the average value of 0.53 mg/g in 20 ℃ showed significantly higher than 0.093 mg/g of 50 ℃ (p<0.05). Based on the results of this study, we confirmed that paints for auto-vehicle contained formaldehyde over 0.1%, the listing criteria for carcinogen on the MSDS. In particular, the painters using water-based paints for auto-vehicle could be potentially exposed to formaldehyde at the painting booth.