|
| Adult Occupational Exposure
to Lead
Inhalation of dust and
fume, and ingestion resulting from hand-to-mouth contact with lead-contaminated food,
cigarettes, clothing or other objects, are the major routes of worker exposure to lead.
Once absorbed, lead accumulates in the blood, soft tissues and bones, with the highest
accumulation initially in the liver and kidneys (NIOSH, 1991). Lead is stored in the bones
for decades, and may cause toxic effects in adults as it is slowly released over time.
Chronic overexposure to lead results in damage to the kidneys, gastro-intestinal tract,
peripheral and central nervous systems, reproductive system and the blood-forming organs
(bone marrow). The frequency and severity of symptoms of chronic lead exposure increase as
blood levels increase.
Overt symptoms of lead poisoning in adults generally begin at blood lead levels between 60 and 120 micrograms per deciliter (µg/dl). Neurologic, hematologic, and reproductive effects, however, may be detectable at much lower levels. OSHA recommends a blood lead level no greater than 30 µg/dl to prevent reproductive problems. OSHA Lead Standard In 1978, OSHA promulgated a final lead standard for general industry (29 CFR 1910.1025) This comprehensive standard established a Permissible Exposure Limit (PEL) of 50 micrograms of lead per cubic meter of air (50 µg/m3 )(8-hour time-weighted average), and included requirements for feasible engineering controls, appropriate personal protective equipment, air monitoring, medical surveillance and employee training. Medical removal, with economic protection of wages and benefits, was specified for employees with an average blood level at or above 50 µg/dl. Go to the following sites for more information: |