Work-Related Lung Disease (WoRLD) Surveillance System

Annual Survey of Occupational Injuries and Illnesses, BLS
After passage of the Occupational Safety and Health Act of 1970, the responsibility for collecting statistics on occupational injuries and illnesses was delegated to the Bureau of Labor Statistics (BLS).  The BLS Annual Survey of Occupational Injuries and Illnesses, done in cooperation with participating state agencies, involves data collection by mail from a sample of an average 174,000 private industry establishments each calendar year (1996–2004).  Nearly all industries in the private sector (employers covered by the Occupational Safety and Health Act of 1970) are included.  Annual BLS reports of these data incorporate corresponding data from mine operators, provided to BLS by the Mine Safety and Health Administration (MSHA), and from railroad transportation employers, provided to BLS by the Federal Railroad Administration.  National estimates of injury and illness incidence rates by industry are developed from the survey data.  Beginning in 1992, the survey was expanded to provide more information on illnesses resulting in days away from work, allowing for more detailed classification of respiratory system diseases.  The BLS reports the number and incidence rates of work-related injuries and illnesses in private industry each year.  For this report, annual summary data on respiratory illnesses were abstracted from BLS annual reports on occupational injuries and illnesses.

In contrast with injury data, illness data presented in the BLS annual reports are quite limited because employers typically do not recognize and report illnesses, particularly illnesses with a long latency.  Also, the survey does not cover all workers since it excludes the self-employed; farm operators with fewer than 11 employees; private households; employees in federal, state, and local government agencies; and independent mining contractors.

Since 2003, BLS has classified industry according to the 2002 North American Industry Classification System (NAICS). BLS stopped reporting ‘dust diseases of the lungs’ and ‘respiratory conditions due to toxic agents’ after 2001. Since 2002, BLS combined these conditions and reported them as a new category called ‘respiratory conditions.’ BLS defined these conditions as follows. ‘Dust diseases of the lungs’ (pneumoconioses) includes silicosis, asbestosis, coal workers’ pneumoconiosis, byssinosis, siderosis, and other pneumoconioses. ‘Respiratory condition due to toxic agents’ includes pneumonitis, pharyngitis, rhinitis or acute congestions due to chemicals, dusts, gases or fumes. ‘Respiratory conditions’ includes silicosis, asbestosis, pneumonitis, pharyngitis, farmer’s lung, beryllium disease, tuberculosis, occupational asthma, reactive airways dysfunction syndrome (RADS), chronic obstructive pulmonary disease (COPD), hypersensitivity pneumonitis, rhinitis or acute congestions due to chemicals, dusts, gases or fumes, siderosis, pneumonia, influenza, toxic inhalation injury such as metal fume fever, chronic obstructive bronchitis, other pneumoconioses, and other respiratory system diseases.

For more information: Office of Safety and Health Statistics, Bureau of Labor Statistics, U.S. Department of Labor, 2 Massachusetts Avenue, NE, Washington, DC 20212; and http://www.bls.gov/iif/home.htm and annual reports: Occupational Injuries and Illnesses: Counts, Rates, and Characteristics.

Black Lung Benefit Awards, SSA and DOL
Title IV of the Coal Mine Health and Safety Act of 1969 authorizes a benefits program, providing medical payments and cash stipends for miners totally disabled because of pneumoconiosis arising out of employment in underground coal mining, as well as for surviving spouses of coal miners whose death resulted from the disease or who were entitled to Black Lung benefits at the time of death.  The Social Security Administration (SSA) was assigned initial responsibility for operating the benefits program.  The Black Lung Benefits Act of 1972 continued SSA responsibility for payments to miners granted claims before July 1973, assigned the Department of Labor (DOL) responsibility for claims filed after July 1973, and extended eligibility for benefits to surface coal miners and to surviving children of miners.  This latter provision allowed children to receive benefits if both parents were deceased, or if a surviving spouse ceased to qualify for benefits through remarriage.  In September 1997, in an effort to enhance customer service to Black Lung program beneficiaries, the responsibility for managing all active SSA Black Lung claims was assigned to DOL.  This program change was made permanent in 2002 when the Black Lung Consolidation of Administrative Responsibility Act placed the administration of both programs with DOL. 

For more information: U.S. Department of Labor, Office of Workers’ Compensation Programs, 200 Constitution Avenue, NW, Washington, DC  20210 and annual reports: Social Security Bulletin, Annual Statistical Supplement, 2005; Annual Report to Congress FY2004: Office of Workers' Compensation Programs, U.S. Department of Labor, Employment Standards Administration; and Black Lung Home Page at http://www.dol.gov/esa/regs/compliance/owcp/ca_blba.htm.

Coal Workers’ X-ray Surveillance Program, NIOSH
The Coal Workers' X-ray Surveillance Program (CWXSP) is a NIOSH-administered occupational health program initially mandated by the Coal Mine Health and Safety Act of 1969.  The primary objective of the CWXSP is to screen miners for coal workers' pneumoconiosis (CWP).  Since 1970, coal mine operators have been required to offer a chest radiograph to all workers at U.S. underground coal mines at the time of hire and again three years later.  Subsequently, miners are offered radiographs at approximately five-year intervals.  The examinations are done at no cost to the miners.  In addition to the posterior-anterior chest x-ray, other information is collected, including miner identification, age, tenure, and specific job in the mine.  Beginning in September 2005, NIOSH, in collaboration with the MSHA, initiated an outreach component for the CWXSP, labeled the Enhanced Coal Workers’ Health Surveillance Program (ECWHSP).  The ECWHSP uses a mobile examination unit to provide chest x-ray examinations at easily accessible locations. 

The chest radiographs are read by physicians who have demonstrated proficiency to NIOSH in the use of the International Labour Office (ILO) system for classifying radiographs of the pneumoconioses.  Each chest image is read by at least two readers, and a consensus rule is used to reach a final determination.  The CWXSP defines radiographic evidence of CWP as a final determination of small opacity profusion category of at least 1/0 or large opacities (i.e., larger than one centimeter in diameter).  Any miner with CWP on his/her chest radiograph is offered the option to work in an area of the mine with a respirable coal mine dust level of 1 mg/m3 or less and have personal dust exposures monitored at frequent intervals.

The large numbers of chest x-ray examinations since 1970 provide a means of monitoring the prevalence of CWP among active coal miners at underground mines. Nearly all eligible miners participated during 1970–1974, while participation in the CWXSP was about 42% during the period 2000–2004. The proportion of mine operations that offered the required CWXSP radiographs increased from 90% in 2003 to 94% in 2007. Due to selective participation, the reported tenure-specific prevalence estimates may not be representative of the entire underground coal mine work force. Also, overall crude prevalence estimates may reflect over-representation of newly employed miners. Tabulations of CWXSP data presented in this report vary from those presented in some earlier editions of the Work-Related Lung Disease Surveillance Report due to revised criteria for categorizing tenure and time periods.

Miner employment figures are averages of the employment at all underground mines, as reported by mine operators once per quarter to MSHA.  These figures under-represent total employment (those ever employed during the period) due to continuous turnover in the workforce during each period. 

For more information: Coal Workers' Health Surveillance Program, Surveillance Branch, Division of Respiratory Disease Studies, NIOSH, 1095 Willowdale Road, Morgantown, WV 26505. Phone (304) 285-5724; and at http://www.cdc.gov/niosh/topics/surveillance/ORDS/CoalWorkersHealthSurvProgram.html.

Integrated Management Information System, OSHA
The Integrated Management Information System (IMIS) includes most of the industrial hygiene sample data from Occupational Safety and Health Administration (OSHA) compliance inspections and consultation surveys conducted since May 1979. The data are reported by OSHA compliance safety and health officers and OSHA state consultants. Each IMIS record includes sample date, substance code, airborne concentration, sample type and exposure type, occupation, OSHA permissible exposure limit (PEL), and Standard Industrial Classification codes. IMIS information is entered as events occur in the course of agency activities. Until cases are closed, IMIS entries concerning specific OSHA inspections are subject to continuing correction and updating. Therefore, numbers of samples reported for a given year, or period of years, may differ from those previously reported. NIOSH receives the data yearly from OSHA's IMIS Database.

For more information:  Directorate of Information Technology, Occupational Safety and Health Administration, 200 Constitution Avenue, NW, Washington, DC  20210.  Phone (202) 693-1700.

Metal/Nonmetal Mine Data, MSHA
The metal/nonmetal mine data (MNMD) are records of industrial hygiene samples collected by MSHA inspectors in non-coal surface and underground mines and mills since 1974. This report presents data since 1979, which represent both personal and area samples. Each MNMD record includes sample date, contaminant code, airborne concentration, occupation, MSHA PEL, percent silica and silica concentration where available, standard industrial classification, and the mine and/or mill at which the sample was obtained. In 1982, Congress temporarily removed the surface stone and sand and gravel industries from MSHA’s jurisdiction. During this year the number of respirable dust samples collected is fewer than in other years. The quartz reference standard used for MNMD samples changed in 1988. As a result, the reported percent quartz content, quartz concentrations, and the percentage of samples exceeding the PEL increased in 1988 from 1987. MSHA occasionally revises and updates MNMD files, so the number of records reported for a given year, or period of years, may differ from previous reports.

NIOSH receives the data yearly from MSHA’s TeraData Query System. It should be noted that MSHA changed the procedures used for entering data into the TeraData Query System from field entry with little or no quality assurance checks to computerized input from the Laboratory Information Management System (LIMS) with built-in quality assurance checks to minimize or eliminate data or coding errors. In short, it appears that MSHA’s asbestos data in their preamble and final rule conflicts with the MSHA asbestos data in this report because of the data or coding errors existing in TeraData.

For more information:  Metal and Nonmetal Health Division, Mine Safety and Health Administration, Room 2453, 1100 Wilson Boulevard, Arlington, VA  22209.  Phone (202) 693-9630.

For more information on the quartz reference standard used for the MNMD samples:  Dust Division, Pittsburgh Safety and Health Technology Center, Mine Safety and Health Administration, P.O. Box 18233, Pittsburgh, PA 15236.  Phone (412) 386-6858.

Multiple Cause-of-Death Data, NCHS
The National Center for Health Statistics (NCHS) has made available annual public-use multiple cause-of-death data files. These files contain records of all deaths in the U.S. since 1968 (approximately two million annually) that are reported to state vital statistics offices. Each death record includes codes for up to 20 conditions listed on the death certificate, including both underlying and contributing causes of death in two fields: the entity axis, which preserves diagnostic detail for all listed conditions and their placement on the death certificate; and the record axis, which reorders the codes, removes redundancies, and (infrequently) combines some associated conditions (see Detail Record Layout at http://www.cdc.gov/nchs/about/major/dvs/mcd/1998mcd.htm). Other data include age, race, sex, and state and county of residence at time of death. In addition, usual industry and occupation codes are available for decedents from some states, for certain years during 1985–1999 (see Appendix E). NCHS has determined that certain quality criteria were met by usual industry and occupation data from selected states in some years.

Potential limitations of multiple cause-of-death data include: under- or over-reporting of conditions on the death certificate by certifying physicians; incomplete or no reporting of usual industry and occupation; and non-specificity of some industry and occupation codes.

For more information: Mortality Statistics Branch, Division of Vital Statistics, National Center for Health Statistics, Centers for Disease Control and Prevention, 3111 Toledo Road, Floor 7, Hyattsville, MD 20782. Phone (301) 458-4666; and http://www.cdc.gov/nchs/products/elec_prods/subject/mortmcd.htm. Also refer to the annual reports: Vital Statistics of the United States, Vol. II Mortality (Parts A and B), Public Health Service, National Center for Health Statistics; and http://www.cdc.gov/nchs/products/pubs/pubd/vsus/vsus.htm and http://wonder.cdc.gov/wonder/sci_data/mort/mcmort/mcmort.asp.

For more information on usual industry and occupation codes: "Technical Appendix for 1995" at http://www.cdc.gov/nchs/about/major/dvs/mcd/1998mcd.htm.

The National Occupational Respiratory Mortality System (NORMS), available at http://webappa.cdc.gov/ords/norms.html, is a data-storage and interactive data-retrieval system developed and maintained by NIOSH. The system contains national census data (see Population Data Estimates, Bureau of the Census (BoC) and Centers for Disease Control (CDC), below) and national mortality data obtained annually from the NCHS public-use multiple cause-of-death data files (see above).  For the  pneumoconioses, malignant mesothelioma, and hypersensitivity pneumonitis, NORMS offers a range of search options for generating tables, charts, and maps of the number of deaths, crude death rates, age-adjusted death rates, and years of potential life lost at national, regional, state, and county levels for U.S. residents by age, race, sex, and Hispanic origin. For all of the respiratory conditions listed in Appendix C, NORMS users can tabulate deaths, years of potential life lost, and proportionate mortality ratios by usual industry and/or occupation for a subset of states and years (Appendix E), 1985–1999.

National Health Interview Survey, NCHS
The National Health Interview Survey (NHIS) is a multi-purpose health survey conducted by NCHS since 1957.  It provides information on the health of the civilian, noninstitutionalized population of the U.S.  NHIS data are collected annually through a personal household interview from approximately 40,000 households and include about 100,000 persons.  The households selected for interview in the NHIS are a probability sample representative of the target population.  The annual response rate of the NHIS is near 90% of the eligible households in the sample. For this report, the 1997–2004 NHIS adult (18 years and older) household interview data were used.

For more information:  Division of Health Interview Statistics, National Center for Health Statistics, 3311 Toledo Road, Hyattsville, MD 20782. Phone (800) 232-4636; and  http://www.cdc.gov/nchs/nhis.htm.

National Hospital Discharge Survey, NCHS
Estimated numbers of hospital discharges presented in this report have been abstracted from National Hospital Discharge Survey (NHDS) reports published by NCHS.  The NHDS, conducted yearly by NCHS, collects data on the use of short-stay non-Federal hospitals in the U.S.  Federal, military, and Department of Veterans Affairs hospitals were excluded in the survey.  In recent years, data have been abstracted from approximately 270,000 records from about 500 hospitals.  Each discharge record includes information on patient age, race, sex, ethnicity (since 1985), marital status, length of stay, source of payment (since 1977), diagnoses (principal and other diagnosis) and surgical procedures, hospital size, ownership, and region of the U.S.

Only hospitals with six or more beds for patient use and those in which the average length of stay for all patients is less than 30 days are included in the survey.  One limitation of NHDS data is that they represent number of discharges, not number of patients.  In addition, information is available only nationally and by region, but not by state.  The NHDS relies on the completeness of hospital medical records, and findings can be influenced by diagnostic practices.

For more information: Division of Health Care Statistics, National Center for Health Statistics, 3311 Toledo Road, Hyattsville, MD 20782, and www.cdc.gov/nchs/about/major/hdasd/nhds.htm.

Occupational and Environmental Disease Surveillance Database Case Reports, AOEC
The Association of Occupational and Environmental Clinics (AOEC) has maintained a database for occupational and environmental diseases and chronic injuries since 1991.  Data summarized and supplied by AOEC in three reports for 1994–1996, 1997–2000, and 2001–2004 are used in this report.  The summary reports provide descriptions of cases with diagnoses associated with occupational exposures other than asbestos, asbestos exposures, and environmental exposures.  They also provide description of cases with diagnoses that are probably associated with occupational or environmental exposures. For this report, diagnoses with probable associated exposures were not included in the total diagnoses. AOEC defines a case as one that must have at least one diagnosed condition that, in the physician’s judgment, is more likely than not to be related to occupational or environmental exposures.  A case can have up to three diagnosed conditions and each condition can have up to three hazards or exposures.

Sixteen AOEC member clinics contributed cases for the period 1994–2004; 4,720 cases had diagnoses associated with asbestos exposure and 5,280 cases had diagnoses associated with occupational exposures other than asbestos. Five clinics participated in at least nine years of the 11-year period and contributed 85% of the cases.  Four other clinics contributed over 150 cases each (13% of all cases).  While not necessarily representative of all patients with work-related conditions, these case reports provide insight into the types of occupational conditions being treated by occupational medicine specialists, as well as into the types of exposures that are causing or exacerbating these diseases.

For more information:  Association of Occupational and Environmental Clinics, 1010 Vermont Avenue, NW, #513, Washington, DC  20005.  Phone (202) 347-4976; and http://www.aoec.org.

Population Data Estimates, BoC and CDC
National population estimates are based on national, state, and county-level data from the BoC.  All population estimates used to compute death rates for 1968–1999 have been obtained through the Centers for Disease Control (CDC) computer system.   Estimates obtained from unmodified intercensal Demo-Detail files were used for 1970–1979 (http://wonder.cdc.gov/wonder/sci_data/census/inter/type_txt/inter708.asp) and for 1980–1989 (http://wonder.cdc.gov/wonder/sci_data/census/inter/type_txt/y8090bur.asp).  The unmodified 1970 intercensal population estimates were used for 1968–1969 because no other county-level population estimates were available.  Postcensal Demo-Detail estimates (http://wonder.cdc.gov/wonder/sci_data/census/post/type_txt/demo95.asp) were used for 1990–1995.   Comparable postcensal estimates prepared by the BoC (http://wonder.cdc.gov/wonder/sci_data/census/post/type_txt/cen9097.asp) were used for 1996–1999.  Since 2000, NCHS bridged-race estimates (http://www.cdc.gov/nchs/about/major/dvs/popbridge/popbridge.htm) have been used: for data years 2000–2002, the bridged-race vintage 2002 postcensal estimates of the resident population of the U.S. as of July 1, 2000, July 1, 2001, and July 1, 2002 (file name "pcenv2002.txt"); for data year 2003, the bridged-race vintage 2003 postcensal estimates of the resident population of the U.S. as of July 1, 2003 (file name "pcen_v2003_y03.txt"); and for data year 2004, the bridged-race vintage 2004 postcensal estimates of the resident population of the U.S. as of July 1, 2004 (file name "pcen_v2004_y04.txt").  [Note: Comparison of population statistics from Demo-Detail and BoC postcensal estimates for each year from 1990 through 1995, showed that there was a maximum annual difference of less than 0.05 percent, and a difference of 0.01 percent or less in a majority of years.  State-specific differences for the same years were less than one percent for individual states, with very rare exceptions.]

For more information: 1990 Census of the Population, General Population Characteristics, U.S. Bureau of the Census, Series 1900, CP-1; http://www.census.gov/main/www/cen1990.html;  http://www.census.gov/main/www/cen2000.html.  For more information on population estimates: http://www.census.gov/popest/estimates.php.

Respirable Coal Mine Dust Data, MSHA
The data consist of respirable coal mine dust measurements collected by MSHA inspectors and mine operators at surface and underground coal mines and facilities since 1970. Each record includes sample date, duration, and airborne concentration, as well as occupation and the mine or facility at which the sample was obtained. NIOSH receives the data yearly from MSHA's Laboratory Information Management System (LIMS) Database.

For more information: Information Resource Center, Mine Safety and Health Administration, P.O. Box 25367, Denver, CO  80225.  Phone (303) 231-5475.

Respirable Coal Mine Quartz Dust Data, MSHA
The data consist of respirable quartz measurements collected by MSHA inspectors and mine operators at surface and underground coal mines and facilities since 1982. Each record includes sample date, duration, percent quartz, and airborne concentration, as well as occupation and the mine or facility at which the sample was obtained. NIOSH receives the data yearly from MSHA's Pittsburgh Quartz Database.

For more information:  Dust Division, Pittsburgh Safety and Health Technology Center, Mine Safety and Health Administration, P.O. Box 18233, Pittsburgh, PA 15236.  Phone (412) 386-6858.

Sentinel Event Notification Systems for Occupational Risks (SENSOR), NIOSH
In 1987, the National Institute for Occupational Safety and Health (NIOSH) began the SENSOR program and awarded cooperative agreements to various state health departments and other state entities to develop models for state-based and condition-specific surveillance and preventive intervention. Two of the conditions for which states have been funded through this program were silicosis and work-related asthma (WRA). States and years funded for these two conditions are shown in Table A-1.

SENSOR Silicosis.  Three states (Michigan, New Jersey, and Ohio) maintained silicosis surveillance for the full 10-year period for which SENSOR silicosis data are presented in this report (1993–2002).  All three states identified potential cases using a variety of sources: review of state death certificate data, case reports from physicians, and review of hospital discharge data or direct hospital reporting to the state health department. In addition, Michigan and Ohio reviewed workers’ compensation records.

In all three states, demographic, work history, and medical information used for case confirmation and description was obtained through a combination of case report review from the initial case ascertainment source, review of medical records, and follow-up telephone interview with the reported cases or their surviving next-of-kin.

California maintained a NIOSH-funded silicosis surveillance program for the last three years (2000–2002) of the 10-year period for which SENSOR silicosis data are presented in this report.  California identified potential cases by reviewing data from DFR of Occupational Injury or Illness, a longstanding statewide physician reporting system linked to physician reimbursement for medical services, as well as data sources mentioned above.  Demographic, work history, and medical information used for case confirmation and description was obtained through a combination of case report review from the initial case ascertainment source, review of medical records, and follow-up telephone interview with the reported cases or their surviving next of kin.

For surveillance purposes, silicosis case confirmation requires a history of occupational exposure to airborne silica dust and either or both of the following: (a) a chest radiograph or other imaging technique interpreted as consistent with silicosis, or (b) lung histopathology characteristic of silicosis (see Appendix G).

For more information: Maxfield R, Alo C, Reilly MJ, et al. Surveillance for silicosis, 1993—Illinois, Michigan, New Jersey, North Carolina, Ohio, Texas, and Wisconsin. MMWR CDC Surveill Summ 1997 Jan 31;46:13-28 at http://www.cdc.gov/mmwr/preview/mmwrhtml/00046046.htm.

SENSOR WRA. A total of four states (California, Massachusetts, Michigan, and New Jersey) maintained WRA surveillance programs during the 10-year period for which SENSOR WRA data are presented in this report (1993–2002). Physician case reports were the primary ascertainment source in all four states. Massachusetts, Michigan, and New Jersey actively solicited physicians for case reports, whereas California identified potential cases by reviewing data from DFR of Occupational Injury or Illness, a longstanding statewide physician reporting system linked to physician reimbursement for medical services. In addition, Michigan and New Jersey actively solicited hospital reports and reviewed hospital discharge records for potential WRA cases. In 1993, Massachusetts began supplementing case ascertainment with review of state-wide hospital discharge data.  In 2002, Michigan began supplement case ascertainment with review of state poison control data.

In all four states, surveillance staff collected demographic data, work history, and medical information for surveillance case confirmation, classification, and description purposes through a combination of the initial case ascertainment source, a review of medical records, and follow-up telephone interview with reported cases. WRA case confirmation requires a healthcare professional’s diagnosis of asthma (or a related diagnosis consistent with asthma) and an association between symptoms of asthma and workplace exposures or conditions. Confirmed WRA cases are classified according to established criteria (see Appendix G). To facilitate consistency in agent coding across states, putative causes of WRA are coded using the AOEC exposure coding scheme (http://www.aoec.org/tools.htm), which flags “known asthma inducers.”

For more information: Jajosky RA, Harrison R, Reinisch F, et al. Surveillance of work-related asthma in selected U.S. states using surveillance guidelines for state health departments—California, Massachusetts, Michigan, and New Jersey, 1993–1995. MMWR CDC Surveill Summ 1999 Jun 25;48:1-20 at http://www.cdc.gov/mmwr/preview/mmwrhtml/ss4803a1.htm.