The Occupational Lead Poisoning Prevention Program (OLPPP) of the California Department of Health Services and a county health department investigated cases of lead poisoning in six furniture workers and their families in 1998. The investigation, initiated after a blood test of a worker's child revealed an elevated blood lead level (BLL), found that lead remaining in previously painted or coated stripped wood was carried from the workplace on clothes and shoes and was the source of the child's lead exposure and subsequent poisoning. Employers in industries in which workers restore or build using stripped wood should assess lead exposure and, when necessary, should establish a comprehensive lead safety program.
During a routine medical examination, the 18-month-old child of a worker received a BLL test at his mother's request. The result, 26 µg/dL, met the CDC-recommended criterion for a lead poisoning case requiring clinical management (i.e., BLLs ≥20 µg/dL).1 A county public health nurse conducted a home visit and arranged blood testing of other family members. Laboratory tests revealed that the father, who worked for a company that refinished antique furniture, had a BLL of 46 µg/dL and his 4-month-old daughter a BLL of 24 µg/dL.
The nurse contacted OLPPP, the state program that provides follow-up for occupational lead poisoning cases. An OLPPP industrial hygienist interviewed the employer who described the process for repairing and restoring wood furniture. Before arriving at the shop, the furniture was chemically stripped of all paint or coatings and was believed to be free of lead. Four carpenters made necessary repairs using power tools such as saws and planers. In an adjacent outdoor courtyard, two refinishers smoothed the wood using manual and power sanders, washed the furniture, and applied wax. Workers routinely ate and drank in work areas, wore no protective equipment, and returned home in work clothes and shoes.
OLPPP instructed the employer to provide BLL and zinc protoporphyrin testing for the six workers and encouraged testing through the county of six family members who might have been affected by lead toxicity. All six workers had elevated BLLs: the two refinishers had BLLs of 29 and 54 µg/dL, and the four carpenters had BLLs of 46, 46, 47, and 56 µg/dL. The Occupational Safety and Health Administration lead regulation requires employees with BLLs ≥40 µg/dL to receive a medical examination, additional laboratory testing, and follow-up.2 Five of the six family members, aged 7-12 years, did not have elevated BLLs; however, a 7-month-old infant, whose father's BLL was >40 µg/dL, had a BLL of 16 µg/dL; it was 15 µg/dL on retesting 30 days later.
OLPPP recommended that the employer establish a comprehensive lead safety program that included exposure monitoring, good hygiene practices, medical examinations, protective clothing, respiratory protection, safe dust clean-up methods, and training. The employer arranged personal exposure monitoring and surface wipe sampling for lead and implemented workplace improvements, including a respiratory protection program; use of HEPA vacuum-attached power sanders; use of a high-efficiency toxic dust HEPA vacuum; daily clean uniforms; separate storage lockers, changing area with showers, and lunch room; warning signs; safety training addressing take-home lead; and a lead medical surveillance program. Workers' BLLs declined after these steps were taken, and the average BLL decreased 15 µg/dL in approximately 3 months.
The nurse advised the affected families on cleaning residences and vehicles. At the residence of the index case, a wipe sample taken on a carpet where the worker played with his children showed a lead surface concentration of 30 µg/ft2. After steam cleaning the carpet, the level was 14 µg/ft2. This lead level on interior floors is below 40 µg/ft2, the threshold level the Environmental Protection Agency has determined to be harmful.3 In addition to the take-home lead contamination, the investigation identified deteriorated lead paint, which the landlord remediated. When the 4-month-old infant's BLL remained elevated several months later, more thorough testing of painted surfaces was performed, and the landlord was required to remediate additional lead painted surfaces. The infant's BLL then decreased steadily.
B Materna, PhD, Occupational Lead Poisoning Prevention Program, California Dept of Health Svcs. Div of Surveillance, Hazard Evaluations, and Field Studies, National Institute for Occupational Safety and Health, CDC.
Exposure to lead in paints and coatings is a known health risk, and recommendations have been made to prevent exposure.4,5 This investigation revealed that wood chemically stripped of lead-containing coatings can retain harmful amounts of lead. The process of alkaline stripping can cause lead to migrate from the paint layer into the pores of the wood substrate.6 Although the wood appears uncoated, sufficient airborne lead dust is released while using power and hand tools to cause surface contamination and elevated BLLs in workers.7
Employers in industries that sand or otherwise disturb lead-impregnated stripped wood (e.g., furniture refinishing and construction) may be unaware of the risk for lead exposure and therefore may not be taking adequate precautions. Public health agencies that address lead issues should send hazard alerts to trade associations and employers in the affected industries. The incident in this report illustrates that industries that handle chemically stripped wood need to comply with lead safety measures, including exposure assessment and control, provision of work clothing and shoes, good hygiene and workplace housekeeping practices, employee training, and medical surveillance. This incident also underscores that a thorough investigation of a childhood lead poisoning case should consider the occupations of adults in the household. Where take-home lead is suspected, BLL tests of the adults can help to confirm workplace exposure. Follow-up at the work-site, including screening of other workers and their young children, can identify others at risk.
Occupational and Take-Home Lead Poisoning Associated With Restoring Chemically Stripped Furniture—California, 1998. JAMA. 2001;285(17):2187-2188. doi:10.1001/jama.285.17.2187-JWR0502-2-1