Chronological Trend in Blood Lead Levels between 1976 and 1980

Abstract

Analysis of a chronological trend in data from the second National Health and Nutrition Examination Survey indicated that average blood lead levels in the United States dropped approximately 37 per cent (5.4 micrograms per deciliter) from February 1976 through February 1980. There was no evidence that this trend was due to errors in laboratory measurement or to the design of the survey. The trend was present even after accounting for differences in race, sex, age, region of the country, season, income, and degree of urbanization. Changes in exposure to lead in paint or in the diet are unlikely explanations of the trend. However, the correlation of blood lead levels with the lead level in gasoline was highly significant (P less than 0.001) overall and in population subgroups defined by race, sex, and age. Although strong correlation does not prove cause and effect, the most likely explanation for the fall in blood lead levels is a reduction in the lead content of gasoline during this period.

Health hazard evaluation report: HETA-91-0366-2453, Delaware County Resource Recovery Facility, Chester, Pennsylvania.

“…12 The mean blood lead level for U.S. men from 1976-1980 was 16 :g/dL. [13][14] With the implementation of lead-free gasoline and reduced lead in food, the 1991 average serum lead level of U.S. men was expected to drop below 9 :g/dL. 15 Recent epidemiological data indicate an overall mean blood lead for the U.S. population of 2.8 :g/dL and a mean adult blood lead level of <5 :g/dL.…”

Health hazard evaluation report: HETA-88-357-2042, A.W. Cash Valve Manufacturing Corp., Decatur, Illinois.

“…Adults not exposed to lead at work usually have a blood lead concentration less than 30 ug/dl; the average is less than 15 ug/dl. 7,8 In 1985, the Centers for Disease Control (CDC) recommended 25 ug/dl as the highest acceptable blood level for young children. 9 Since the blood lead concentration of a fetus is similar to that of its mother, and since the fetus' s brain is presumed to be at least as sensitive to the effect of lead as a child' s, the CDC advised that a pregnant woman' s blood lead level be below 25 ug/dl.…”

“…In their request, the AIWA expressed concern about potential employee exposures to lead from brass castings during use of the Dedicated Goss machines, crystalline silica (nuisance dust) during shot blasting, and Freon 113 during the reclamation process. Subsequently, NIOSH visited the plant on February 16 and August [8][9]1989.…”

“…On August [8][9]1989, NIOSH returned to administer questionnaires and to conduct biological (blood) monitoring and additional air sampling for lead. Twenty-seven out of thirty potentially exposed employees agreed to participate in the biological monitoring portion of this survey.…”

Health hazard evaluation report: HETA-87-410-1868, Klotz Brothers, Incorporated, Staunton, Virginia.

“…Adults not exposed to lead at work usually have a blood lead concentration less than 30 ug/dl; the average is less than 15 ug/dl (3,4). In 1985, the Centers for Disease Control (CDC) recommended 25 ug/dl as the highest acceptable blood level for young children (5).…”