S. Sperber, University of Delaware, Newark, DE.
This presentation will discuss the occupational health and safety challenges of removing several layers of lead-based paint from a historic, century old building that is being adapted for use as an art gallery.
This facility, Mechanical Hall, located on the University of Delaware Campus in Newark, was built in 1898 to house the Mechanical and Electrical Engineering Departments and, later, the campus’s Army ROTC. In 2001, the University decided to renovate the building as the permanent home of the Paul R. Jones Collection of African-American Art. The building will also provide research and office spaces for the gallery staff members.
One of the chief elements of the architect’s vision for the renovation involved revealing and restoring the building’s original heavy timber support structure, wooden deck, and brick walls to their original condition. Unfortunately, the interior painted surfaces contained many layers of paint with high percentages of lead. The University’s Department of Occupational Health and Safety was challenged with preparing specifications for the safe removal of the lead-based paint—one that would guarantee minimal damage to the wooden surfaces.
The traditional paint removal technique (chemical paint strippers) was not effective in removing all of the layers of paint, and its use would have been too time consuming to meet time constraints for the project. The University’s OHS Department determined that this would be the perfect opportunity to be unorthodox and sandblast the interior painted surfaces of the building. The building was unoccupied due to the renovation, so the entire building could be sealed and maintained under negative pressure. Through sample testing it was determined that sandblasting off the paint would meet the stringent restoration requirements of the project.
This presentation will discuss the criteria used in contractor selection, health and safety measures, area/personal air sampling, and management of waste during the project.
K. Ashley, M. Boeniger, CDC/NIOSH, Cincinnati, OH; E. Esswein, CDC/NIOSH, Denver, CO.
A new National Institute for Occupational Safety and Health method for detecting lead contamination on surfaces is described. A wetted wipe is used to collect dust on surfaces that potentially contain lead. Lead in dust collected on the wipe is extracted using an aqueous acidic solution, such as diluted acetic acid (vinegar) or highly diluted nitric acid. The wipe is then treated with an aqueous solution of rhodizonic acid in order to test for the presence of lead. A characteristic color of pink or red is indicative of a positive test for lead. The procedure is best performed using spray bottles containing extraction solution and indicator solution, respectively; a fine spray is preferred. The estimated identification limit of the method, when using vinegar for extraction, is about 10–15 micrograms of lead per wipe sample. Matrix effects and potential interferences must be taken into consideration when using the procedure. As a screening technique, the method is suitable for testing surfaces such as floors, walls, window sills, car interiors, and skin. The method is especially useful for detecting the presence of lead on skin and assessing the effectiveness of hand washing in removing lead from the hands of exposed individuals. Also, the method is particularly useful in field evaluation for the presence of lead in dust, and the effectiveness of its subsequent removal in the workplace, home, school, or other environments.
W. Rossiter, Jr., B. Toman, M. McKnight, I. Emenanjo, M. Baghai Anaraki, NIST, Gaithersburg, MD.
WITHDRAWN
M. Tortora, Hartford Hospital, Hartford, CT.
Many different metal parts are fabricated in an RO fabrication lab. This manufacturing process involves the melting, drilling, and reforming of parts used in radiation treatments. The metal alloys that are used in this process contain several metals, including lead and cadmium. A by-product of the manufacturing process is the contamination of environmental surfaces (e.g. floors, counter tops), particularly with lead and cadmium. This causes a potental occupational hazard as exposure to these metals becomes a possibility for workers in the lab. Although air monitoring demonstrates that there are no airborne hazards, routine dust wipes sampling indicates an aggressive build up of both lead and cadmium levels on lab surfaces. Regular cleaning of these surfaces is unsuccessful in removing the contamination, so a special cleaning agent is used to acheive this. Sampling immediately before, immediately after, and several days after the cleaning procedure demonstrates that the procedure is successful in decontaminating surfaces in the lab, thus controlling the build up of lead and cadmium dust and possible employee exposure.
C. Clark, R. Clark, University of Cincinnati, Cincinnati, OH; V. Thuppil, G. Menezes, H. D’Souza, St. John’s Medical College, Bangalore, India; S. Sinha, Awengaia Environmental Consultants, Bangalore, India; N. Nayak, A. Kuruvilla, Kasturba Medical College, Mangalore, India; P. Dave, S. Shah, Sardar Patel University, Vallabh Vidyanagar, India.
In a 1999 blood lead survey of 23,000 children and adults in 7 cities in India, 53% of children under 10 years of age were found to have levels of 10 µg/dl or higher, the current U.S CDC limit. In a recent report on sources of childhood lead poisoning in countries such as India, the nine major sources listed: lead gasoline, lead-glazed ceramics, mining and smelting, battery repair and recycling, cottage industries, flour mills, medication and cosmetics, and consumer products. It did not include lead in paint. A recent report, however, indicates that an estimated 10% of the lead in India is reported to be used in making paint. In 1999, an examination of a selection of 24 new paints available for purchase in India found that four had lead concentrations exceeding 0.5% lead by weight (the U.S. limit for paint in housing) and one contained more than 10% lead. Information could not be located on the lead content of paint in housing in India. The availability of field portable X-Ray fluorescence analyzers with a Cd109 source provided an opportunity to examine the residential environments of 10 children with blood lead levels of 40 µg/dl and higher, and to again measure the content of new paints. In one half of the residential environments, three or more locations measured had lead levels of 1.0 mg/cm2 or higher, levels considered “lead-based paint” in the U.S. Overall, about 10% of the surfaces tested had levels of 1.0 mg/sq cm or higher. Other sources of lead exposure observed were lead storage batteries and traditional medicine. In new paints tested, almost one-third measured 1.0 mg/sq cm or higher after the application of three coats. Similar surveys would be useful elsewhere in India and in other developing countries.
E. Babayan, R. Hovanesyan, A. Aleksandryan, G. Aleksandryan, V. Kafyan, Institute of General Hygiene and Occupational Diseases, Yerevan, Armenia; L. Saryan, Aurora Consolidated Laboratories, West Allis, WI.
Aim: To develop a plan to prevent lead poisoning.
Materials and Methods: Atomic absorption spectrophotometry was applied to analyze samples of air, soil, dust settled on internal surfaces, and working clothes. “Stata” program was applied for quantitative analysis.
Results: Research carried out at two manufacturers of lead crystal and crystal products showed that the industrial ambient environment is polluted with lead. In the majority of cases lead exceeded permissible levels. Blood lead analyses of 259 children and 47 adult inhabitants at the polluted sites, and also 143 workers from crystal factories, revealed that at one settlement the blood lead level of 18.7% of children achieved 10–20 mcg/dL. At the other locality this level exceeded 43.7% of the children surveyed, and in 3.7% the level exceed 20 mcg/dL. Blood lead level in workers ranged 15–89 mcg /dL (in 21% above 60 mcg/dL). In children the level of protoporphyrin was normal, but in the majority of workers it reached 220–529 mcg/dL. Questionnaires and interviews administered to assess the level of knowledge of parents of children, workers exposed to lead, teachers, and neighborhood medical personnel about lead indicated a low degree of awareness. The analysis of this data by “Stata” program showed a positive correlation between the presence of a factory worker in a family and the level of lead in blood of children (OR = 13). Correlation (OR = 3; P =0.014) of socioeconomic status and level of knowledge about lead was revealed. To reduce the impact of lead and to prevent lead poisoning in children, an educational program for parents and personnel at schools and polyclinics was developed. A special program for worker training, covering technical and hygienic actions at lead-using enterprises for the prevention of harmful influence of lead, was developed.
Posted May 30, 2004