Massachusetts Department of Public Health Data Highlights
Lead – A Toxic Metal Lead is a heavy metal that can cause health problems in children and adults. Adults who inhale or ingest lead can experience anemia, nervous system dysfunction, kidney problems, hypertension, infertility, and miscarriage. Children exposed to low levels of lead may suffer neurological damage including learning disabilities and short attention spans. Lead is also a probable carcinogen.1,2 The average blood lead level (BLL) in the general population is less than three micrograms per deciliter of blood (µg/dl). BLLs of 10 µg/dl or greater are considered abnormally high in both adults and children.3 BLLs in the 14-30 µg/dl range may cause small increases in blood pressure. BLLs as low as 30 µg/dl may cause nervous system dysfunction. Abdominal pain may occur in some adults at BLLs of about 40 µg/dl. Abnormal sperm and decreased sperm counts have been observed in men with BLLs of approximately 40 µg/dl. The workplace is the primary source of lead exposures for adults. Workers in many industries, including bridge and house painting, deleading, battery manufacturing, and radiator repair are exposed to potentially dangerous levels of lead. Lead is also found in work processes such as welding, smelting, and soldering. Workers can bring lead home on their clothes, shoes, or tools and expose their families. The Massachusetts Occupational Lead Poisoning Registry The purpose of the Lead Registry, located in the Massachusetts Division of Occupational Safety, is to reduce lead poisoning among Massachusetts workers and their families by identifying workers and workplaces with overexposures to lead. Since 1991, clinical laboratories in Massachusetts have been required by state law to report blood lead levels of 15 µg/dl or greater in individuals age 15 or older to the Lead Registry. Lead Registry staff enter all reports into a computerized database and follow up reports of elevated BLLs with interviews and education of workers and physicians, workplace investigations, and employer education and technical assistance. Lead Registry staff interview individuals with BLLs of 40 µg/dl or greater, as well as their health care providers, to learn more about the sources of lead exposure and employer lead poisoning prevention practices. These individuals and their physicians receive educational materials. If a child under six lives in the home, the Lead Registry sends information on free blood lead testing programs. If deemed appropriate, inspectors conduct worksite investigations. For every report of a BLL of 60 µg/dl or greater, the Lead Registry’s medical consultant contacts the physician who ordered the blood test to provide them with information on treatment of lead poisoning and Occupational Safety and Health Administration (OSHA) requirements for medical monitoring of lead exposed workers. The Massachusetts Occupational Lead Poisoning Registry participates in a nationwide adult lead surveillance program known as ABLES (Adult Blood Lead Epidemiology and Surveillance), maintained by the National Institute for Occupational Safety and Health. ABLES tracks BLLs of 25 µg/dl or greater in adults using data from clinical laboratory tests collected by states throughout the country. In 2002, ABLES identified 10,658 adults with BLLs 25 µg/dl or greater in 35 states.4 Terms and Methods Used in This Report This report describes cases of elevated BLLs reported to the Lead Registry from 1996 through 2001. A “case” is an individual 15 years or older with a reported BLL greater or equal to 25 µg/dl for whom there were no reports of elevated BLLs in the previous calendar year. The same individual can be counted as a case more than once during the six-year surveillance period. For example, an individual who was in the Lead Registry in 1996, did not appear in the Lead Registry in 1997, but reappeared in 1998 is counted as two cases. The “annual incidence rate” of elevated BLLs is the number of new cases of elevated BLLs per 100,000 employed workers per year. Information on the number of Massachusetts workers employed each year was obtained from the Current Population Survey conducted by the US Bureau of Labor Statistics. The frequencies and rates in this report are based on the highest BLL reported for each case during the surveillance period. Limitations of the Surveillance Data Given resource limitations, detailed information about cases with BLLs less than 40 µg/dl was not collected by the Registry until 2001. Therefore, there is no information on the sources of lead exposure or employer lead poisoning prevention practices for these cases. It is important to note that many individuals are never tested for lead exposure, even if they work in industries in which workers are known to be exposed to lead. This is especially true of workers in small establishments. Cases of Blood Lead Levels 25 µg/dl or Greater Magnitude of the Problem
Sources of Exposure
Work-Related Cases of BLLs 40 µg/dl or Greater Industries
Information from Worker Interviews* Follow-up interviews were completed with 193 (64%) of the cases with BLLs of 40 µg/dl or greater who had occupational exposures. The main reason for failure to interview was inability to contact the individual by phone. Bridge painters, many of whom come from out of state, were much less likely to complete interviews (7, 33%) than cases employed in other industries.Race and Ethnicity
*Not all interviewed cases answer all questions. Percentages in this
section are based on numbers responding to the specific questions.
Training on Lead Hazards at the Workplace
Medical Removal of Cases with Very High Blood Lead Levels
The OSHA Lead Standards OSHA has legal standards for protecting employees from lead exposure in both general industry and the construction industry (Code of Federal Regulations 1910.1025 and 1926.62). These standards require blood lead testing for employees who perform jobs that may expose them to certain levels of lead. The general industry standard requires medical removal from work with payment of wages (Medical Removal Protection) for employees with a single and confirmatory BLL of ≥60 µg/dl, or average BLLs ≥50 µg/dl based on the last three BLLs or all BLLs over the previous six months (whichever covers a longer time period). The construction industry standard requires Medical Removal Protection for employees with BLLs ≥50 µg/dl. These standards require employers to train all employees who may be occupationally exposed to lead about lead hazards, preventing lead exposure, and using respirators. Changes over Time: 1991–1995 vs. 1996–2001 The Occupational Lead Registry began collecting data in April 19915. Findings from 1996–2001 were compared to findings from the 1991–1995 surveillance period. Magnitude
Conclusions & Recommendations The US Public Health Service has called for eliminating cases of BLLs of ≥25 µg/dl due to occupational exposures by the year 2010.6 While occupational lead poisoning in Massachusetts declined steadily from 1991 to 2001, a trend similar to declines seen in other states, several hundred cases of elevated BLLs continued to be reported each year. Lead exposures can result in short-term and long-term health problems for the exposed workers and potentially other members of their households. Continued efforts are needed to prevent occupational lead exposures in Massachusetts. The findings in this report highlight the problem of lead exposure in the Massachusetts construction industry, especially in painting and deleading. Workers in these two industries accounted for 65% of the cases with BLLs of 40 µg/dl or greater. The continued presence of deleaders and bridge painters in the Lead Registry, even though they reported being trained about lead, underscores the hazardous nature of these industries and the need to be vigilant in implementing exposure control measures. House painters accounted for an increasing proportion of the cases reported over time and had some of the highest blood lead levels. They also appeared much less likely than either bridge painters or deleaders to have participated in employer medical monitoring programs or to have been trained about lead hazards. Innovative strategies are needed to reach the house painting industry to promote compliance with lead standards, including required blood lead testing and training as well as measures to prevent exposures. The finding that Hispanic workers appear to be disproportionately exposed to lead is consistent with Lead Registry findings reported by other states and with evidence that minority workers are more likely than other workers to be employed in high-risk job categories. It highlights the need for culturally and linguistically appropriate interventions targeting Hispanic workers, particularly in construction. Resources Massachusetts Division of Occupational Safety Occupational Lead Poisoning Registry 617–969–7177 Asbestos and Lead Program (deleading certification) 617–727–7047 US Occupational Safety and Health Administration (OSHA) Region I, 617–565–9860 Massachusetts Coalition for Occupational Safety and Health 617–825–7233 Massachusetts Department of Public Health Childhood Lead Poisoning Prevention Program 617–624–5757 Occupational Health Surveillance Program 617-624-5632 References 1 International Agency for Research on Carcinogens. Inorganic and Organic Compounds. IARC 2004; 87 (February 10-17). 2 National Toxicology Program, US Department of Health and Human Services. Report on Carcinogens, 11th Edition, 2004. 3 Centers for Disease Control and Prevention, Morbidity and Mortality Weekly Report, Blood Lead Levels–United States, 1999- 2002.Vol. 54, No 20, May 27, 2005. 4 Centers for Disease Control and Prevention, Morbidity and Mortality Weekly Report,Vol. 53, No 26, July 9, 2004. 5 Massachusetts Departments of Labor and Workforce Development and Public Health, Lead at Work: Elevated Blood Lead Levels in Massachusetts Workers,April 1991–December 1995, 1998. 6 US Department of Health and Human Services. Healthy People 2010,Washington DC: January 2000. Acknowledgements The Lead Registry would like to thank Rokho Kim, MD, DrPH, and Olivier Humblet, MS, who assisted in the development of this report. The Massachusetts Occupational Lead Poisoning Registry is supported in part by funds from the National Institute for Occupational Safety and Health. This paper appears in the eLCOSH website with the permission of the author and/or copyright holder and may not be reproduced without their consent. eLCOSH is an information clearinghouse. eLCOSH and its sponsors are not responsible for the accuracy of information provided on this web site, nor for its use or misuse. eLCOSH | CDC | NIOSH | Site Map | Search | Links | Help | Contact Us | Privacy Policy |