Lead Exposures from Varnished Floor Refinishing

Abstract

We evaluated the presence of lead in varnish and factors predicting lead exposure from floor refinishing and inexpensive dust suppression control methods. Lead in varnish, settled dust, and air were measured using XRF, laboratory analysis of scrape and wipe samples, and National Institute for Occupational Safety and Health (NIOSH) Method 7300, respectively, during refinishing (n = 35 homes). Data were analyzed using step-wise logistic regression. Compared with federal standards, no lead in varnish samples exceeded 1.0 mg/cm², but 52% exceeded 5000 ppm and 70% of settled dust samples after refinishing exceeded 40 μg/ft². Refinishing pre-1930 dwellings or stairs predicted high lead dust on floors. Laboratory analysis of lead in varnish was significantly correlated with airborne lead (r = 0.23, p = 0.014). Adding dust collection bags into drum sanders and HEPA vacuums to edgers and buffers reduced mean floor lead dust by 8293 μg Pb/ft² (p<0.05) on floors and reduced most airborne lead exposures to less than 50 μg/m³. Refinishing varnished surfaces in older housing produces high but controllable lead exposures.

[Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: a PDF file containing a table showing all raw data for all environmental measurements for each house in this study.]

Keywords:

• floor sanding
• housing
• intervention
• lead dust
• lead paint
• lead poisoning
• renovation

ACKNOWLEDGMENTS

We thank participating homeowners, the staff of the University of Wisconsin Occupational Health Laboratory, and Peter Ashley at the US Department of Housing and Urban Development, Office of Healthy Homes and Lead Hazard Control. This study was funded by the U.S. Department of Housing and Urban Development's Office of Healthy Homes and Lead Hazard Control (WILTS0084-00).