Occupational Lead Poisoning in the United States: Clinical and Biochemical Findings Related to Blood Lead Levels.
Baker-EL Jr.; Landrigan-PJ; Barbour-AG; Cox-DH; Folland-DS; Ligo-RN; Throckmorton-J
Bureau of Epidemiology, Center for Disease Control, Atlanta, Georgia :32 pages
A study was made of 160 lead (7439921) exposed workers at a secondary lead smelter, a small scrap smelter, and a lead chemicals facility to investigate dose response relationships between blood lead levels and toxic effects. The levels of blood lead ranged from percent of the total number, clinical evidence of toxic exposure was detected including colic in 33, wrist or ankle extensor muscle weakness in 12, anemia in 27, elevated blood urea nitrogen (BUN) in 28, and possible encephalopathy in two. At blood lead levels below 1.93micromol/l no toxicity was detected. However, 13 percent of those workers with blood lead levels of 1.93 to 3.81micromol/l had extensor muscle weakness or gastrointestinal symptoms. In 5 percent of the workers with lead levels of 1.93 to 2.85micromol/l, anemia was noted. Anemia was also noted in 14 percent with levels between 2.90 and 3.81micromol/l and in 36 percent with levels over 3.86micromol/l. In long term lead workers elevated BUN occurred. All but three workers with elevated BUN had at least 4 years of occupational lead exposure, and nine had received oral chelation therapy. Eight of this group had reduced creatinine clearance and eight had decreased renal concentrating ability. These findings supported the establishment of a permissible biological limit for blood lead at a level between 1.93 and 2.90micromol/l.
Blood-analysis; Lead-poisoning; Lead-smelting; Muscle-function; Neuromuscular-system-disorders; Heavy-metals; Gastrointestinal-system-disorders; Occupational-exposure;
NTIS Accession No.
Bureau of Epidemiology, Center for Disease Control, Atlanta, Georgia, 32 pages, 45 references