Blood lead level measuring

Children with elevated PbB (12-120 pg/dL) were found to have significantly lower serum concentrations of the vitamin D metabolite 1,25-dihydroxy vitamin D compared with age-matched controls (p<0.001), and showed a negative correlation of serum 1,25-dihydroxyvitamin D with lead over the range of blood lead levels measured (Mahaffey et al. 1982 Rosen et al. 1980). 

Blood lead levels measured as a part of the National Health and Nutrition Examination Surveys (NHANES) revealed that between 1976 and 1991, the mean PbB levels of the U.S. population aged from 1 to 74 years dropped 78%, from 12.8 to 2.8 pg/dL. The prevalence of PbB levels 10 pg/dL also decreased sharply from 77.8% to 4.3%. The major cause of the observed decline in PbB levels is most likely... 

Borja-Aburto VH, Hertz-Picdotto I, Rojas LM, Farias P, Rios C, Blanco J (1999) Blood lead levels measured prospectively and risk of spontaneous abortion. Am J Epidemiol, 150 590-597. 

Under this program, the blood lead level (BLL) of all employees who are exposed to lead above 30 g/m for more than 30 days per year or whose blood lead is above 40 ig/dl but exposed for no more than 30 days per year Is to be determined at least every two months for the first six months of exposure and every six months thereafter. The frequency is increased to every two months for employees whose last blood lead level was 40 ig/dl or above. For employees who are removed from exposure to lead due to an elevated blood lead, a new blood lead level must be measured monthly. A zinc protoporphyrin (ZPP) measurement is strongly recommended on each occasion that a blood lead level measurement is made. 

Borja-Aburto, V. H., I. Hertz-Picciotto, M. Rojas Lopez, et al. 1999. Blood Lead Levels Measure Prospectively and Risk of Spontaneous Abortion. American Journal of Epidemiology 150 590-597. 

Preventive Measures. The intake uptake biokinetic model (lUBK) projects the impact of lead in the environment on blood lead. This model assumes conservatively high levels of intake and cannot account for chemical speciation, thus over-predictions of blood lead levels often occur. Nonetheless, because of the allegations of the impact of blood lead and neurobehavioral development, blood lead levels in children are being reduced adrninistratively to below 10 //g/dL. In order to do so, soil leads are being reduced to a level of between 500—1000 ppm where remediation is required. 

Background measurements, soil samples, 119-20 Blood-lead levels In preschool... 

The amount of total lead in the blood can be measured to determine if exposure to lead has occurred. This test can tell if you have been recently exposed to lead. Lead can be measured lead in teeth or bones by X-ray techniques, but these methods are not widely available. These tests tell about long-term exposures to lead. Exposure to lead can be evaluated by measuring erythrocyte protoporphyrin (EP) in blood samples. EP is a part of red blood cells known to increase when the amount of lead in the blood is high. However, the EP level is not sensitive enough to identify children with elevated blood lead levels below about 25 micrograms per deciliter ( ig/dL). For this reason, the primary screening method is measurement of blood lead. For more information on tests to measure lead in the body, see Chapters 2 and 6. 

NS (chronic) (general population) Other No association between blood lead levels and growth in children 10-47 (levels measured) Greene and Emhart 1991 Sachs and Moel 1989... 

NS (general population) Developmental No association between blood lead levels and birth weight, gestational age, or other neonatal size measures 3-55 Factor-Litvak et al. 1991 Greene and Ernhart 1991... 

Blood lead levels, urinary lead levels, serum creatinine, blood urea nitrogen (BUN), creatinine clearance (CCT), and NAG were measured in 158 male and 51 female workers in a lead battery factory or a lead smelting plant in Japan (Ong et al. 1987). Controls consisted of 30 professional and laboratory staff members with no history of renal disease or lead exposure. The length of exposure to lead averaged 10.8 8.0 years with a range of 1-36 years. Exposure levels were not available, but indicators of lead body burden in the exposed workers were PbB level = 3.0-80.0 pg/dL and urinary lead level =... 

Analysis of the unadjusted data showed that all postnatal blood lead levels were inversely associated with Full Scale IQ measured at age 10 however, only the associations involving PbB level at ages 10 years,... 

A later analysis (Emhart et al. 1987) related PbB levels obtained at delivery (maternal and cord blood) and at 6 months, 2 years, and 3 years of age to developmental tests (MDI, PDI, Kent Infant Development Scale [KID], and Stanford-Binet IQ) administered at 6 months, 1 year, 2 years, and 3 years of age, as appropriate. After controlling for covariates and confounding risk factors, the only significant associations of blood lead with concurrent or later development were an inverse association between maternal (but not cord) blood lead and MDI, PDI, and KID at 6 months, and a positive association between 6-month PbB and 6-month KID. The investigators concluded that, taken as a whole, the results of the 21 analyses of correlation between blood lead and developmental test scores were "reasonably consistent with what might be expected on the basis of sampling variability," that any association of blood lead level with measures of development was likely to be due to the dependence of both PbB and... 

An adverse effect of lead on pregnancy rate has been noted in some animal studies (Kennedy et al. 1975). Acute-duration gavage administration of 390 mg lead/kg/day as lead acetate to rats resulted in a sharp decrease in pregnancy rates. This effect was not noted at 39 mg lead/kg/day. The study limitations include a lack of measurement of blood lead levels and lack of statistical analysis of pregnancy incidence. A decrease in the number of implantations was noted in untreated female mice that were mated to males that had been treated with 141 mg/kg/day lead chloride in the drinking water for 3 months... 

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