Bone Lead Testing Facility

Publications

Clinical Case Conference: Neuropsychiatric Implications of Lead Toxicity.
Cassleman KL, Capaldi VF, Dorrance KA, Todd AC. Mil. Med. 2019. PMID 31670374 doi: 10.1093/milmed/usz362. 
This study describes the case of a 42-year-old active duty officer with a history of anxiety, cognitive impairment and paroxysmal hypertensive episodes who, while yielding low or unremarkable blood-lead levels, was nonetheless found to have elevated body burdens of lead, as measured in bone.

Cocaine addiction severity exacerbates the negative association of life-time lead exposure with blood pressure levels.
Colicino E, Hazeltine DB, Schneider KM, Zilverstand A, Bachi K, Alia-Klein N, Goldstein RZ, Todd AC, Horton MK. Environmental Disease 4 (3) 75-80, 2019. doi: 10.4103/ed.ed_21_19
Cumulative lead exposure and cocaine use have been independently associated with increased blood pressure. Individuals with cocaine use disorder (CUD) and healthy (non-cocaine using) controls were measured via KXRF to compare bone lead levels with blood pressure. Bone lead levels were found to be elevated in users and were associated with higher blood pressure for both groups.

Bone lead associations with blood lead, kidney function and blood pressure among US, lead-exposed workers in a surveillance programme.
Barry V, Todd AC, Steenland K. Occup Environ Med. 2019 Jan 19. pii: oemed-2018-105505. doi: 10.1136/oemed-2018-105505. [Epub ahead of print]
Bone and blood lead, blood pressure and estimated glomerular filtration rate levels were collected from adult men in a lead surveillance program. Regression models were used to determine the associations of blood lead, kidney function and blood pressure with bone lead.

A cohort mortality study of lead-exposed workers in the USA, Finland and the UK.
Steenland K, Barry V, Anttila A, Sallmén M, McElvenny D, Todd AC, Straif K. Occup Environ Med. 2017 Nov;74(11):785-791. doi: 10.1136/oemed-2017-104311. Epub 2017 May 25
Mortality in three cohorts of lead-exposed workers was analyzed via Cox regression to determine whether inorganic lead is a carcinogen among adults or is associated with increased blood pressure and kidney damage.

Associations of multiple metals with kidney outcomes in lead workers: author response.
Shelley R, Kim NS, Parsons PJ, Lee BK, Jaar BG, Fadrowski J, Agnew J, Matanoski G, Schwartz BS, Steuerwald AJ, Todd AC, Simon D, Weaver VM. Occup Environ Med. 2014 Feb;71(2):154. doi: 10.1136/oemed-2013-101809. Epub 2013 Nov 28.
No abstract available.

Uranium associations with kidney outcomes vary by urine concentration adjustment method.
Shelley R, Kim NS, Parsons PJ, Lee BK, Agnew J, Jaar BG, Steuerwald AJ, Matanoski G, Fadrowski J, Schwartz BS, Todd AC, Simon D, Weaver VM. J Expo Sci Environ Epidemiol. 2014 Jan-Feb;24(1):58-64. doi: 10.1038/jes.2013.18. Epub 2013 Apr 17
Creatinine clearance, serum creatinine- and cystatin-C-based estimated glomerular filtration rates, and N-acetyl-β-D-glucosaminidase (NAG) in lead workers were collected during a 4-hour urine collection to determine the nephrotoxic effects of uranium.

Tibial bone lead, but not serum polychlorinated biphenyl, concentrations are associated with neurocognitive deficits in former capacitor workers.
Seegal RF, Fitzgerald EF, McCaffrey RJ, Shrestha S, Hills EA, Wolff MS, Haase RF, Todd AC, Parsons PJ, Molho ES, Higgins DS, Factor SA, Seibyl JP. J Occup Environ Med. 2013 May;55(5):552-62. doi: 10.1097/JOM.0b013e318285f3fd
To determine the relationships between tibia lead and serum polychlorinated biphenyl concentrations and neurocognitive function, regression analyses were performed to evaluate the association between neurocognitive function and lipid-adjusted serum polychlorinated biphenyl and tibia lead concentrations in former capacitor workers.

Associations of multiple metals with kidney outcomes in lead workers.
Shelley R, Kim NS, Parsons P, Lee BK, Jaar B, Fadrowski J, Agnew J, Matanoski GM, Schwartz BS, Steuerwald A, Todd A, Simon D, Weaver VM. Occup Environ Med. 2012 Oct;69(10):727-35. doi: 10.1136/oemed-2012-100765. Epub 2012 Jul 26
Using multiple linear regressions, the authors evaluated the associations of antimony and thallium with kidney outcomes and assessed the impact of cadmium exposure on those associations in lead workers.

An interlaboratory comparison of bone lead measurements via K-shell X-ray fluorescence spectrometry: validation against inductively coupled plasma mass spectrometry.
Bellis DJ, Todd AC, Parsons PJ. J Anal At Spectrom. 2012;27(4):595-603. Epub 2012 Feb 7
In this validation study to standardize X-ray fluorescence bone lead measurements, a set of nine goat tibiæ were circulated to eleven laboratories where the lead values were measured using X-ray fluorescence to standardize the method.

Increased lead biomarker levels are associated with changes in hormonal response to stress in occupationally exposed male participants.
Fortin MC, Cory-Slechta DA, Ohman-Strickland P, Nwankwo C, Yanger TS, Todd AC, Moynihan J, Walton J, Brooks A, Fiedler N. Environ Health Perspect. 2012 Feb;120(2):278-83. doi: 10.1289/ehp.1103873. Epub 2011 Nov 23
To determine the effects of lead on responses of the HPA axis to a psychosocial laboratory stressor, the serum cortisol and plasma adrenocorticotropic hormone were assessed in seventy lead-exposed male participants during and after administration of the Trier Social Stress Test. Lead in blood (recent exposure marker) and lead in tibia bone (chronic exposure marker) via K XRF were measured.

Differences in urine cadmium associations with kidney outcomes based on serum creatinine and cystatin C.
Weaver VM, Kim NS, Lee BK, Parsons PJ, Spector J, Fadrowski J, Jaar BG, Steuerwald AJ, Todd AC, Simon D, Schwartz BS. Environ Res. 2011 Nov;111(8):1236-42. doi: 10.1016/j.envres.2011.07.012. Epub 2011 Aug 25
Comparison between the associations of urine cadmium with kidney function measures, based on serum cystatin C to those with serum creatinine in lead workers.

Estimating the half-lives of PCB congeners in former capacitor workers measured over a 28-year interval.
Seegal RF, Fitzgerald EF, Hills EA, Wolff MS, Haase RF, Todd AC, Parsons P, Molho ES, Higgins DS, Factor SA, Marek KL, Seibyl JP, Jennings DL, McCaffrey RJ. J Expo Sci Environ Epidemiol. 2011 May-Jun;21(3):234-46. doi: 10.1038/jes.2010.3. Epub 2010 Mar 10
To address the fact that most estimates of the half-life of polychlorinated biphenyls in humans have been based on relatively short follow-up periods, the authors reviewed the PCB congener analysis of archived blood from former capacitor workers approximately 28 years after their last occupational exposure. Bone lead was measured as a confounder.

Associations of low-level urine cadmium with kidney function in lead workers.
Weaver VM, Kim NS, Jaar BG, Schwartz BS, Parsons PJ, Steuerwald AJ, Todd AC, Simon D, Lee BK. Occup Environ Med. 2011 Apr;68(4):250-6. doi: 10.1136/oem.2010.056077. Epub 2010 Oct 25
Urine cadmium with four glomerular filtration measures and N-acetyl-β-D-glucosaminidase in lead workers were evaluated to understand the impact of low-level cadmium exposure in workers who are occupationally exposed to other nephrotoxicants such as lead. Recent and cumulative lead doses were assessed via blood and tibia lead, respectively.

Occupational exposure to PCBs reduces striatal dopamine transporter densities only in women: a beta-CIT imaging study.
Seegal RF, Marek KL, Seibyl JP, Jennings DL, Molho ES, Higgins DS, Factor SA, Fitzgerald EF, Hills EA, Korrick SA, Wolff MS, Haase RF, Todd AC, Parsons P, McCaffrey RJ. Neurobiol Dis. 2010 May;38(2):219-25. doi: 10.1016/j.nbd.2010.01.009. Epub 2010 Jan 20
To test the hypothesis that occupational exposure to PCBs is associated with a reduction in central dopamine, the authors used [(123)I]beta-CIT SPECT imaging to estimate basal ganglia DA transporter density in former capacitor workers. Bone lead was measured as a confounder.

Cumulative lead dose and cognitive function in older adults.
Bandeen-Roche K, Glass TA, Bolla KI, Todd AC, Schwartz BS. Epidemiology. 2009 Nov;20(6):831-9. doi: 10.1097/EDE.0b013e3181b5f100
Six summary measures of cognitive function were created from standard tests in the following domains: language, processing speed, hand-eye coordination, executive functioning, verbal memory and learning, and visual memory. Longitudinal linear modeling was then performed to evaluate associations of tibia lead concentration with cognitive function and decline, and whether such cognitive effects are persistent, reversible or progressive.

Neighborhood psychosocial hazards and the association of cumulative lead dose with cognitive function in older adults.
Glass TA, Bandeen-Roche K, McAtee M, Bolla K, Todd AC, Schwartz BS. Am J Epidemiol. 2009 Mar 15;169(6):683-92. doi: 10.1093/aje/kwn390. Epub 2009 Jan 20
An evaluation of whether cross-sectional associations of tibia lead with cognitive function are modified by neighborhood psychosocial hazards in the Baltimore Memory Study, a longitudinal cohort study of determinants of cognitive decline.

Longitudinal associations between lead dose and renal function in lead workers.
Weaver VM, Griswold M, Todd AC, Jaar BG, Ahn KD, Thompson CB, Lee BK. Environ Res. 2009 Jan;109(1):101-7. doi: 10.1016/j.envres.2008.09.005. Epub 2008 Nov 26
Generalized estimating equations were used to model change in renal function, lead dose and renal outcomes in lead workers to determine if lead dose predicts change in renal function.

Relationship between lead exposure, cognitive function, and drug addiction: pilot study and research agenda.
Fishbein DH, Todd AC, Ricketts EP, Semba RD. Environ Res. 2008 Nov;108(3):315-9. doi: 10.1016/j.envres.2008.07.012. Epub 2008 Aug 27
The tibial lead concentrations in 26 female injection heroin users were measured via 109Cd-based K-shell X-ray fluorescence to determine whether these users have high tibial lead concentrations compared with the standard reference populations, and whether cognitive deficits potentiated the relationship between lead exposure and frequency of heroin use.

Development of candidate reference materials for the measurement of lead in bone.
Hetter KM, Bellis DJ, Geraghty C, Todd AC, Parsons PJ. Anal Bioanal Chem. 2008 Jul;391(6):2011-21. doi: 10.1007/s00216-008-2085-x. Epub 2008 Apr 18
To develop reference materials, long-bones obtained from Pb-dosed and undosed animals were ground in an ultra-centrifugal mill, resulting in finely powdered bone material that was homogenized and then sample-scooped into vials. The homogenized bones were then tested for contamination and homogeneity, performed via instrumental methods of analysis.

Gender and race/ethnicity differences in lead dose biomarkers.
Theppeang K, Glass TA, Bandeen-Roche K, Todd AC, Rohde CA, Schwartz BS. Am J Public Health. 2008 Jul;98(7):1248-55. doi: 10.2105/AJPH.2007.118505. Epub 2008 May 29
Participants were randomly identified from selected neighborhoods in Baltimore, Maryland, and lead concentrations were measured by anodic stripping voltammetry (in blood) and 109Cd-based K-shell x-ray fluorescence (in bone). Multiple linear regressions were then used to identify predictors of lead concentrations in the blood, tibiae and patellae of older adults, and to describe differences by gender, race/ethnicity and other factors that modify health effects.

Associations of bone mineral density and lead levels in blood, tibia, and patella in urban-dwelling women.
Theppeang K, Glass TA, Bandeen-Roche K, Todd AC, Rohde CA, Links JM, Schwartz BS. Environ Health Perspect. 2008 Jun;116(6):784-90. doi: 10.1289/ehp.10977
Measurements of the lumbar spine bone mineral density in 112 women were performed to evaluate the relations between bone mineral density and lead in the blood, tibia and the patella to investigate how bone mineral density modifies these lead biomarkers in older women.

Associations between patella lead and blood pressure in lead workers.
Weaver VM, Ellis LR, Lee BK, Todd AC, Shi W, Ahn KD, Schwartz BS. Am J Ind Med. 2008 May;51(5):336-43. doi: 10.1002/ajim.20573
Cross-sectional data from lead workers were analyzed to compare the associations of patella lead with blood lead in models of blood pressure and hypertension.

Parathyroid hormone status does not influence blood and bone lead levels in dialysis patients.
Ghosh-Narang J, Jones TM, Menke A, Todd AC, Muntner P, Batuman V. Am J Med Sci. 2007 Dec;334(6):415-20
Serum parathyroid hormone, calcium and phosphorus levels, in addition to a tibia lead measurement collected via 109Cd-based x-ray fluorescence, were obtained from fifty-one African-American patients with end-stage renal disease to evaluate whether higher blood lead levels are due to a release of lead from the skeleton as a result of uremic bone disease.

Association of tibia lead and blood lead with end-stage renal disease: a pilot study of African-Americans.
Muntner P, Menke A, Batuman V, Rabito FA, He J, Todd AC. Environ Res. 2007 Jul;104(3): 396-401. Epub 2007 May 18
Two cohorts of African Americans, one with and one without end-stage renal disease, were followed to determine the association between body lead levels (blood and bone) and the burden of kidney disease.

Environmental lead exposure and cognitive function in community-dwelling older adults.
Shih RA, Glass TA, Bandeen-Roche K, Carlson MC, Bolla KI, Todd AC, Schwartz BS. Neurology. 2006 Nov 14;67(9):1556-62. Epub 2006 Sep 13
Using multiple linear regressions, a cross-sectional analysis was performed to evaluate associations of recent (blood) and cumulative (bone) lead dose with cognitive function and to determine if long-term exposure to high levels of lead in the environment is associated with decrements in cognitive ability in older Americans.

Changes in systolic blood pressure associated with lead in blood and bone.
Glenn BS, Bandeen-Roche K, Lee BK, Weaver VM, Todd AC, Schwartz BS. Epidemiology. 2006 Sep;17(5):538-44
Followed a cohort of 575 Korean lead-exposed workers to evaluate blood pressure change between study visits in relation to tibia lead concentrations at each prior visit and concurrent changes in blood lead. The modeling strategy summarized the longitudinal association of blood pressure with cumulative lead dose or changes in recent lead dose.

Effect modification by delta-aminolevulinic acid dehydratase, vitamin D receptor, and nitric oxide synthase gene polymorphisms on associations between patella lead and renal function in lead workers.
Weaver VM, Lee BK, Todd AC, Ahn KD, Shi W, Jaar BG, Kelsey KT, Lustberg ME, Silbergeld EK, Parsons PJ, Wen J, Schwartz BS. Environ Res. 2006 Sep;102(1):61-9. Epub 2006 Feb 17
An assessment of the effect modification by polymorphisms in the genes on the associations of higher patella lead and adverse renal outcomes in Korean lead workers.

Comparison of patella lead with blood lead and tibia lead and their associations with neurobehavioral test scores.
Dorsey CD, Lee BK, Bolla KI, Weaver VM, Lee SS, Lee GS, Todd AC, Shi W, Schwartz BS. J Occup Environ Med. 2006 May;48(5):489-96
The associations of depreciated cognitive function and lead exposure in lead workers were explored by performing a cross-sectional analysis of the relations of patella lead and other lead biomarkers with measures of neurobehavioral and peripheral nervous system function.

Past adult lead exposure is linked to neurodegeneration measured by brain MRI.
Stewart WF, Schwartz BS, Davatzikos C, Shen D, Liu D, Wu X, Todd AC, Shi W, Bassett S, Youssem D. Neurology. 2006 May 23;66(10):1476-84
The associations of persistent brain lesions and the accumulation of lead in organolead workers was assessed via MRI measures of white matter lesions and cumulative lead dose via tibia lead. 

Association of blood lead and tibia lead with blood pressure and hypertension in a community sample of older adults.
Martin D, Glass TA, Bandeen-Roche K, Todd AC, Shi W, Schwartz BS. Am J Epidemiol. 2006 Mar 1;163(5):467-78. Epub 2006 Jan 18
An analysis of the associations of blood lead, tibia lead, systolic and diastolic blood pressure, and hypertension in a community-based cohort of men and women 50-70 years of age in Baltimore, Maryland.

Associations of uric acid with polymorphisms in the delta-aminolevulinic acid dehydratase, vitamin D receptor, and nitric oxide synthase genes in Korean lead workers.
Weaver VM, Schwartz BS, Jaar BG, Ahn KD, Todd AC, Lee SS, Kelsey KT, Silbergeld EK, Lustberg ME, Parsons PJ, Wen J, Lee BK. Environ Health Perspect. 2005 Nov;113(11):1509-15
Data were analyzed on these three genetic polymorphisms to understand the mechanisms for lead-related nephrotoxicity and patella lead burden.

Associations of patella lead and other lead biomarkers with renal function in lead workers.
Weaver VM, Lee BK, Todd AC, Jaar BG, Ahn KD, Wen J, Shi W, Parsons PJ, Schwartz BS. J Occup Environ Med. 2005 Mar;47(3):235-43
Levels of the blood urea nitrogen, serum creatinine, creatinine clearances and other biomarkers of lead workers were captured to compare the associations of patella lead with other lead measures in models of renal function.

Associations among lead dose biomarkers, uric acid, and renal function in Korean lead workers.
Weaver VM, Jaar BG, Schwartz BS, Todd AC, Ahn KD, Lee SS, Wen J, Parsons PJ, Lee BK. Environ Health Perspect. 2005 Jan;113(1):36-42
Data from lead workers were collected and analyzed to determine whether lead biomarkers were associated with uric acid. Additional analyses were conducted to understand if the previously reported associations between lead and renal outcomes were altered after adjustments for uric acid were made.

Prospective study of blood and tibia lead in women undergoing surgical menopause.
Berkowitz GS, Wolff MS, Lapinski RH, Todd AC. Environ Health Perspect. 2004 Dec;112(17):1673-8
Women over 30 years of age were followed during October 1994 through April 1999 to determine the mobilization of bone lead stores during surgical menopause.

The G(894)-T(894) polymorphism in the gene for endothelial nitric oxide synthase and blood pressure in lead-exposed workers from Korea.
Lustberg ME, Schwartz BS, Lee BK, Todd AC, Silbergeld EK. J Occup Environ Med. 2004 Jun;46(6):584-90
An evaluation of a potential association of the G -T polymorphism in exon 7 of the endothelial nitric oxide synthase gene blood pressure or the modification of the relation between bone lead concentration and blood pressure.

Associations of patella lead with polymorphisms in the vitamin D receptor, delta-aminolevulinic acid dehydratase and endothelial nitric oxide synthase genes.
Theppeang K, Schwartz BS, Lee BK, Lustberg ME, Silbergeld EK, Kelsey KT, Parsons PJ, Todd AC. J Occup Environ Med. 2004 Jun;46(6):528-37
A cross-sectional analysis evaluated associations of polymorphisms in the vitamin D receptor and endothelial nitric oxide synthase genes with patella lead concentrations in lead workers.

Change in blood lead concentration up to 1 year after a gunshot wound with a retained bullet.
McQuirter JL, Rothenberg SJ, Dinkins GA, Kondrashov V, Manalo M, Todd AC. Am J Epidemiol. 2004 Apr 1;159(7):683-92
The time course and prevalence of elevated blood lead concentrations, bone lead concentration, associated injuries and patient-specific factors were examined during the first year following a gunshot injury. 

Associations of renal function with polymorphisms in the delta-aminolevulinic acid dehydratase, vitamin D receptor, and nitric oxide synthase genes in Korean lead workers.
Weaver VM, Schwartz BS, Ahn KD, Stewart WF, Kelsey KT, Todd AC, Wen J, Simon DJ, Lustberg ME, Parsons PJ, Silbergeld EK, Lee BK. Environ Health Perspect. 2003 Oct;111(13):1613-9
Samples collected from lead workers were analyzed to determine whether specific biomarkers including the vitamin D receptor and nitric oxide synthase, are associated with or modified by relations of lead exposure, as measured by K XRF, and renal outcomes.

Associations of lead biomarkers with renal function in Korean lead workers.
Weaver VM, Lee BK, Ahn KD, Lee GS, Todd AC, Stewart WF, Wen J, Simon DJ, Parsons PJ, Schwartz BS. Occup Environ Med. 2003 Aug;60(8):551-62
Clinical renal function in lead workers was assessed by measuring blood urea nitrogen, serum creatinine, and the retinol-binding protein, to determine associations of lead biomarkers, as measured by K XRF, with renal function.

Calculating the uncertainty in lead concentration for in vivo bone lead x-ray fluorescence.
Todd AC, Chettle DR. Phys Med Biol. 2003 Jul 7;48(13):2033-9
A revised mathematical treatment of the calibration line intercept for in vivo bone lead measurements obtained via 109Cd-based K-shell x-ray fluorescence.

Elevated blood lead resulting from maxillofacial gunshot injuries with lead ingestion.
McQuirter JL, Rothenberg SJ, Dinkins GA, Norris K, Kondrashov V, Manalo M, Todd AC. J Oral Maxillofac Surg. 2003 May;61(5):593-603
X-ray fluorescence measurements were performed on patients who had suffered gunshot wounds to the face, possibly causing the ingestion of lead particles from a retained bullet.

An agreed statement on calculating lead concentration and uncertainty in XRF in vivo bone lead analysis.
Chettle DR, Arnold ML, Aro AC, Fleming DE, Kondrashov VS, McNeill FE, Moshier EL, Nie H, Rothenberg SJ, Stronach IM, Todd AC. Appl Radiat Isot. 2003 May;58(5):603-5. No abstract available
Contributors to the development and use of x-ray fluorescence from various institutions lay out the equations and calculations they agree on for concentration calculation.

The relationship between blood lead, bone lead and child intelligence.
Wasserman GA, Factor-Litvak P, Liu X, Todd AC, Kline JK, Slavkovich V, Popovac D, Graziano JH. Child Neuropsychol. 2003 Mar;9(1):22-34
Blood-lead-IQ associations were compared with bone-lead measurement results in children 10-12 years of age.

Corrections to “How to calculate lead concentration and concentration uncertainty in XRF in vivo bone lead analysis” by Kondrashov and Rothenberg.
Todd AC, Moshier EL, Arnold M, Aro A, Chettle DR, McNeill FE, Nie H, Flemming DE, Stronach IM. Appl Radiat Isot. 2003 Jan;58(1):41-50; author reply 51-4
Compares and contrasts various approaches to calculating lead concentrations and uncertainties.

The longitudinal association of lead with blood pressure.
Glenn BS, Stewart WF, Links JM, Todd AC, Schwartz BS. Epidemiology. 2003 Jan;14(1):30-6
Blood, bone lead measurements and blood pressure were taken in a group of current and former chemical-manufacturing employees. Results were analyzed to assess a possible interaction with blood pressure changes.

Increases in hypertension and blood pressure during pregnancy with increased bone lead levels.
Rothenberg SJ, Kondrashov V, Manalo M, Jiang J, Cuellar R, Garcia M, Reynoso B, Reyes S, Diaz M, Todd AC. Am J Epidemiol. 2002 Dec 15;156(12):1079-87. Erratum in: Am J Epidemiol. 2007 Jul 15;166(2):241
Lead exposure (current and past) has been considered to increase hypertension and blood pressure. To examine the association, a group of women were measured prenatal and postnatal, and the lead levels were analyzed for their potential influence on blood pressure.

ApoE genotype, past adult lead exposure, and neurobehavioral function.
Stewart WF, Schwartz BS, Simon D, Kelsey K, Todd AC. Environ Health Perspect. 2002 May;110(5):501-5
Bone lead measurements were made in a group of former organolead workers and, using a linear regression model, the relationship of the lead levels, neurobehavioral test scores, ApoE genotype and an interaction of the gene with lead were assessed.

L-shell x-ray fluorescence measurements of lead in bone: accuracy and precision.
Todd AC, Carroll S, Geraghty C, Khan FA, Moshier EL, Tang S, Parsons PJ. Phys Med Biol. 2002 Apr 21;47(8):1399-419
Using the L-shell XRF method, measurements were made of bare bones and intact legs and compared to measurements made via electrothermal atomic absorption spectrometry (AAS). Variability and uncertainty were of concern.

Measurements of lead in human tibiae. A comparison between K-shell x-ray fluorescence and electrothermal atomic absorption spectrometry.
Todd AC, Parsons PJ, Carroll S, Geraghty C, Khan FA, Tang S, Moshier EL. Phys Med Biol. 2002 Feb 21;47(4):673-87
The difference in concentrations of lead measurements in human tibiae assessed via K-shell XRF and electrothermal AAS were compared. Effects on the concentration ranges of different regions of the bone were also considered.

L-shell x-ray fluorescence measurements of lead in bone: system development.
Todd AC. Phys Med Biol. 2002 Feb 7;47(3):507-22
Development of the L-shell XRF technique assessed whether there was an advantage to additional fluorescing photons from a secondary target. However, the signal-to-background ratio posed a disadvantage. This paper describes the calibration and sample measurements made.

L-shell x-ray fluorescence measurements of lead in bone: theoretical considerations.
Todd AC. Phys Med Biol. 2002 Feb 7;47(3):491-505 
Assumptions in the reported measurement accuracy and methodological uncertainty are assessed. Corrections to coefficients are debated, and calculations compare the signal strength for the L-shell and K-shell techniques.

Associations of Lead Exposure and Dose Measures with Erythrocyte Protein Kinase C Activity in 212 Current Korean Lead Workers.
Hwang KY, Schwartz BS, Lee BK, Strickland PT, Todd AC, Bressler JP. Toxicol Sci 62 (2) 280-288, 2001 PMID 11452141 doi: 10.1093/toxsci/62.2.280
The protein kinase C in human erythrocytes can be activated by lead after exposure. Lead workers underwent blood and bone lead measurements and those results were compared to the level of activation of isolated protein kinase C.

Associations of lead biomarkers and delta-aminolevulinic acid dehydratase and vitamin D receptor genotypes with hematopoietic outcomes in Korean lead workers.
Lee SS, Lee BK, Lee GS, Stewart WF, Simon D, Kelsey K, Todd AC, Schwartz BS. Scand J Work Environ Health. 2001 Dec;27(6):402-11
This study compares and contrasts associations of dimercaptosuccinic acid (DMSA)-chelatable lead, tibia lead and blood lead with five hematopoietic outcomes and evaluates the effect modification of these relations by polymorphisms in the delta-aminolevulinic acid dehydratase and vitamin D receptor genes.

Patella lead x-ray fluorescence measurements are independent of sample orientation.
Todd AC, Godbold JH, Moshier EL, Khan FA. Med Phys. 2001 Aug;28(8):1806-10
Tibia, calcaneus and patella are the three principal bones for XRF measurements. Patella measurements can also sample lead from the distal femur, proximal tibia and synovium. This study determines the dependence of the concentration and measurement uncertainty on the orientation of the patella to the measurement system.

A pilot evaluation of tibia lead concentrations in Taiwan.
Todd AC, Ginde NR, Ho CK, Luo JC, Tolman J, Tsai JL, Wu TN, Liou SH. Am J Ind Med. 2001 Aug;40(2):127-32
Bone and blood lead were measured in a group of Taiwanese lead workers and compared to workers from other countries.

Tibia lead levels and methodological uncertainty in 12-year-old children.
Todd AC, Buchanan R, Carroll S, Moshier EL, Popovac D, Slavkovich V, Graziano JH. Environ Res. 2001 May;86(1):60-5. Erratum in: Environ Res 2001 Oct;87(2):119
Children 11-12 years old who live in a lead smelter town were measured and compared to a group of control children. The measurements of the children were also compared to measurements of adults to determine sensitivity and statistical uncertainty in the XRF method.

The effects of retained lead bullets on body lead burden.
McQuirter JL, Rothenberg SJ, Dinkins GA, Manalo M, Kondrashov V, Todd AC. J Trauma. 2001 May;50(5):892-9
A group of gunshot victims was studied for the long-term health effects of retained bullets. Bone lead was measured to assess previous lead history, and blood lead was used to assess the contribution from the bullets, both from the time of injury and subsequently. 

Associations of blood pressure and hypertension with lead dose measures and polymorphisms in the vitamin D receptor and delta-aminolevulinic acid dehydratase genes.
Lee BK, Lee GS, Stewart WF, Ahn KD, Simon D, Kelsey KT, Todd AC, Schwartz BS. Environ Health Perspect. 2001 Apr;109(4):383-9
Lead workers and controls had their blood, bone and DMSA-chelatable lead levels measured to examine any association between the effects of lead on blood pressure, hypertension and genes known to modify the toxicokinetics of lead.

Associations of blood lead, dimercaptosuccinic acid-chelatable lead, and tibia lead with neurobehavioral test scores in South Korean lead workers.
Schwartz BS, Lee BK, Lee GS, Stewart WF, Lee SS, Hwang KY, Ahn KD, Kim YB, Bolla KI, Simon D, Parsons PJ, Todd AC. Am J Epidemiol. 2001 Mar 1;153(5):453-64
Nervous system functions, including grip strength and peripheral vibration thresholds, were measured in a group of South Korean lead workers and their associations with the three lead biomarkers were examined.

Seasonal variation in bone lead contribution to blood lead during pregnancy.
Rothenberg SJ, Kondrashov V, Manalo M, Manton WI, Khan F, Todd AC, Johnson C. Environ Res. 2001 Mar;85(3):191-4
Blood lead levels, like vitamin D metabolites, have been seen to fluctuate from summer to winter. Blood lead measurements were made on a group of immigrant women during their third trimester and post-delivery. Bone lead was also measured post-delivery. Lead measurements were analyzed at each stage for the potential influence of seasonal changes.

Associations of tibia lead, DMSA-chelatable lead, and blood lead with measures of peripheral nervous system function in former organolead manufacturing workers.
Tassler PL, Schwartz BS, Coresh J, Stewart WF, Todd AC. Am J Ind Med. 2001 Mar;39(3):254-61
A group of former organolead workers was measured for the three lead biomarkers and sensory pressure thresholds, to see whether there was an association between higher lead levels and peripheral nervous system functions.

Predictors of DMSA chelatable lead, tibial lead, and blood lead in 802 Korean lead workers.
Todd AC, Lee BK, Lee GS, Ahn KD, Moshier EL, Schwartz BS. Occup Environ Med. 2001 Feb;58(2):73-80
The three lead biomarkers were measured to examine their relationship to occupational and environmental exposures. Factors such as age, duration of exposure, education, smoking history etc. were also analyzed in regression models.

The effect of measurement location on tibia lead XRF measurement results and uncertainty.
Todd AC, Carroll S, Godbold JH, Moshier EL, Khan FA. Phys Med Biol. 2001 Jan;46(1):29-40
XRF measurements were made at multiple locations of ten adult cadaver legs and on nine removed tibia bones to determine the optimal location(s) to measure.

Chronic Lead Nephropathy with Excessive Body Lead Burden.
Ahn HC, Hwang KY,  Hong SY, Yang DH, Lee BK, Todd AC. J Occup Health. 42 (5) 2610-262, 2000 doi: 10.1539/joh.42.260
Two patients with occupational lead exposure were assessed for lead-related health effects. Blood, bone and chelatable lead were all measured.

Variability in XRF-measured tibia lead levels.
Todd AC, Carroll S, Godbold JH, Moshier EL, Khan FA. Phys Med Biol. 2000 Dec;45(12):3737-48
The variability of 109Cd-based K-shell XRF lead measurements was evaluated. Replicate measurements were taken multiple times on 10 intact cadaver leg bones, and monthly measurements were made on four in vivo volunteers for one year. Measurement uncertainty and standard deviation of repeated measurements were compared.

Repeatability of tibia lead measurement by X-Ray fluorescence in a battery-making workforce.
Todd AC, Ehrlich RI, Selby P, Jordaan E. Environ Res. 2000 Nov;84(3):282-9
Lead-acid battery manufacturers, who were previously measured in a study for bone lead levels via K-shell x-ray fluorescence, were measured again to assess variability and repeatability. The levels were also linked to duration of exposure; results reinforced the importance of avoiding contamination when performing measurements on active lead workers.

Past adult lead exposure is associated with longitudinal decline in cognitive function.
Schwartz BS, Stewart WF, Bolla KI, Simon PD, Bandeen-Roche K, Gordon PB, Links JM, Todd AC. Neurology. 2000 Oct 24;55(8):1144-50. Erratum in: Neurology 2001 Jan 23;56(2):283
To assess the effects of lead exposure on cognitive function, a group of former organolead manufacturing workers underwent a bone lead measurement. Factoring years of exposure, the workers also took neurobehavioral tests that were compared to a group of control subjects.

Lactation and lead body burden turnover: a pilot study in Mexico.
Moline JM, Lopez Carrillo L, Tores Sanchez L, Godbold JH, Todd AC. J Occup Environ Med. 42 (11) 1070-1075, 2000 PMID 11094785
Lead levels were measured in women of childbearing age at three bone sites, two primarily trabecular (calcaneus and patella) and one primarily cortical (tibia), to determine if there is an association between lead levels and months of lactation. Demographic, reproductive characteristics and potential sources of exposure were also analyzed.

Associations of blood lead, dimercaptosuccinic acid-chelatable lead, and tibia lead with polymorphisms in the vitamin D receptor and [delta]-aminolevulinic acid dehydratase genes.
Schwartz BS, Lee BK, Lee GS, Stewart WF, Simon D, Kelsey K, Todd AC. Environ Health Perspect. 2000 Oct;108(10):949-54
Groups of occupationally exposed lead workers and non-occupationally exposed workers were measured for bone lead, via x-ray fluorescence, and blood lead. These data were used to determine if the delta-aminolevulinic acid dehydratase and vitamin D receptor genes play a role in modifying lead levels in the human body.

Coherent scattering and matrix correction in bone-lead measurements.
Todd AC. Phys Med Biol. 2000 Jul;45(7):1953-63 
X-ray fluorescence used to determine bone lead has been an important technique for studies determining the health effects of lead in those exposed. For this technique, the calibration standard matrix needs a coherent scatter conversion factor in order to be compared to human bone. The impurities that can cause measurement inaccuracy are evaluated and found to be negligible.

Calculating bone-lead measurement variance.
Todd AC. Environ Health Perspect. 2000 May;108(5):383-6. Erratum in: Environ Health Perspect 2000 Jul;108(7):A298
As an extension to the previous papers on the development of the x-ray fluorescence bone-lead measurement technique, this paper corrects typographical errors in the methods published. Measurement uncertainty contributed from computational peak fitting and the importance of covariance are discussed.

Associations of tibial lead levels with BsmI polymorphisms in the vitamin D receptor in former organolead manufacturing workers.
Schwartz BS, Stewart WF, Kelsey KT, Simon D, Park S, Links JM, Todd AC. Environ Health Perspect. 2000 Mar;108(3):199-203
Bone lead x-ray fluorescence measurements were performed on a group of former workers with exposure to lead. The effects of various vitamin D genotypes were analyzed for their influence on bone lead and calcium content. 

Different associations of blood lead, meso 2,3-dimercaptosuccinic acid (DMSA)-chelatable lead, and tibial lead levels with blood pressure in 543 former organolead manufacturing workers.
Schwartz BS, Stewart WF, Todd AC, Simon DS, Links JM. Arch Environ Health 55 (2) 85-92, 2000 PMID 10821507c
In a group of workers, all three lead levels were measured and their influence on blood pressure and hypertension status was assessed.

Contamination of in vivo bone-lead measurements.
Todd AC. Phys Med Biol. 2000 Jan;45(1):229-40
XRF calibration standards constructed from plaster-of-Paris can underestimate in vivo measurements by a small amount. Lead and non-lead contamination may therefore require statistical treatment determined by the calibration line intercept. Calibration refinements are addressed and recommended.

Maternal bone lead contribution to blood lead during and after pregnancy.
Rothenberg SJ, Khan F, Manalo M, Jiang J, Cuellar R, Reyes S, Acosta S, Jauregui M, Diaz M, Sanchez M, Todd AC, Johnson C. Environ Res. 2000 Jan;82(1):81-90
The effects of lead stored in bone on lead in blood during and after pregnancy were determined in a group of women primarily from Latin America. The women were measured during their third trimester and again 1-2 months after delivery. Factors such as years in the United States and sources of exposure were also considered.

Neurobehavioral function and tibial and chelatable lead levels in 543 former organolead workers.
Stewart WF, Schwartz BS, Simon D, Bolla KI, Todd AC, Links J. Neurology. 1999 May 12;52(8):1610-7
An evaluation was made of the associations between tibia lead, dimercaptosuccinic acid (DMSA)-chelatable lead, and neurobehavioral function in former organolead manufacturing workers with past exposure to organic and inorganic lead. Years-since-last-exposure to lead and x-ray fluorescence bone lead measurements were analyzed for their potential influence on neurobehavioral test scores.

Predictors of dimercaptosuccinic acid chelatable lead and tibial lead in former organolead manufacturing workers.
Schwartz BS, Stewart WF, Todd AC, Links JM. Occup Environ Med. 1999 Jan;56(1):22-9
A statistical analysis determined predictors of high tibia lead (cumulative lead absorption) and DMSA chelatable lead (bioavailable lead). Various factors such as age, race, tobacco and alcohol use, height, weight and exposure were compared to tibia lead concentrations and the effects of DMSA chelation therapy on lead levels.

Lead absorption and renal dysfunction in a South African battery factory.
Ehrlich RI, Robins T, Jordaan E, Miller S, Mbuli S, Selby P, Wynchank S, Cantrell A, De Broe ME, D’Haese PC, Todd AC, Landrigan PJ. Occup Environ Med. 55 453-460, 1998 PMID 9816378
Blood lead, years of work exposure and other factors were used to evaluate inorganic lead exposure and its effects on blood pressure and renal function.

Geriatric bone lead metabolism in a female nonhuman primate population.
McNeill FE, Laughlin NK, Todd AC, Sonawane BR, Van de Wal KM, Fowler BA. Environ Res. 1997 Feb;72(2):131-9
In order to compare the metabolism of lead in bone between monkeys and humans, bone lead measurements of geriatric, exposed and non-exposed monkeys were performed, to quantify both the accumulation rate and assess the half-life of lead in bone.

Unraveling the chronic toxicity of lead: an essential priority for environmental health.
Todd AC, Wetmur JG, Moline JM, Godbold JH, Levin SM, Landrigan PJ. Environ Health Perspect. 1996 Mar;104 Suppl 1:141-6. Review
As a prevalent problem in the United States, a study was proposed to expand knowledge of the health effects, causes and treatment of chronic lead toxicity. The study would have assessed bone lead, susceptibility and damage caused to the body.

Improvements in the calibration of 109Cd K x-ray fluorescence systems for measuring bone lead in vivo.
Aro AC, Todd AC, Amarasiriwardena C, Hu H. Phys Med Biol. 1994 Dec;39(12):2263-71
Calibration standards of plaster-of-Paris with known concentrations of lead were measured using K XRF as well as ICPMS to validate the known concentrations.

A pilot study using 99mTc to measure lead and platinum in the human kidney.
Todd AC, Chettle DR, Scott MC, Somervaille LJ, Braithwaite RA, Beaney RP, Buxton EJ. Nucl Med Biol. 1993 Jul;20(5):589-95
Cisplatin(um), a chemotherapy drug, was reported to have mobilized skeletal lead in patients. Using x-ray fluorescence, measurements of lead and platinum in the kidney of chemotherapy patients were made.

In vivo measurements of lead in bone using a 109Cd ‘spot’ source.
Todd AC, McNeill FE. Basic Life Sci. 1993;60:299-302
To further the development of using x-ray fluorescence, the use of 109Cd as a source not only fluoresces lead but also provides a convenient, backscatter geometry. The authors’ method is described in full in this paper.

In vivo measurements of lead in bone in long-term exposed lead smelter workers.
Gerhardsson L, Attewell R, Chettle DR, Englyst V, Lundström NG, Nordberg GF, Nyhlin H, Scott MC, Todd AC. Arch Environ Health. 1993 May-Jun;48(3):147-56
Active and retired lead smelter workers were compared to workers with no lead exposure. Tibia lead measurements were shown to be more precise than calcaneus lead measurements.

The in vivo measurement of bone lead stores by 109Cd K X-ray fluorescence in a non-human primate (Macaca mulatta).
McNeill FE, Todd AC, Fowler BA, Laughlin NK. Basic Life Sci. 1993;60:315-8
Blood lead and bone lead levels were measured and compared in adult and geriatric monkeys with pre-natal lead exposure, post-natal lead exposure and no exposure, to study the effects of low-level lead exposure during infancy, pregnancy and aging.

In vivo X-ray fluorescence of lead in bone.
Todd AC, McNeill FE, Fowler BA. Environ Res. 1992 Dec;59(2):326-35
The three XRF techniques used to perform in vivo measurements (57Co/90o, 109Cd/backscatter K-shell fluorescence and the 125I L-shell fluorescing) were compared. The 109Cd/backscatter technique has been adopted by the majority of groups using the techniques because of the advantages of 1) robust measurements with lower radiation dose to the subject and 2) a lower detection limit.

In vivo X-ray fluorescence of lead in bone using K X-ray excitation with 109Cd sources: radiation dosimetry studies.
Todd AC, McNeill FE, Palethorpe JE, Peach DE, Chettle DR, Tobin MJ, Strosko SJ, Rosen JC. Environ Res. 1992 Apr;57(2):117-32
The effective dose of radiation delivered to a subject during a 30-minute 109Cd-based K XRF bone lead measurement was shown to be of limited concern for in vivo subjects.

Kidney effects in long term exposed lead smelter workers.
Gerhardsson L, Chettle DR, Englyst V, Nordberg GF, Nyhlin H, Scott MC, Todd AC, Vesterberg O. Br J Ind Med. 1992 Mar;49(3):186-92
Kidney function and renal impairment were studied to determine the effects of moderate-to-heavy occupational lead exposure. Lead concentrations in blood and urine were measured in retired and active lead workers with occupational exposure and compared to a control group. 

Monte Carlo modelling of in vivo x-ray fluorescence of lead in the kidney. 
Todd AC, Chettle DR, Scott MC, Somervaille LJ. Phys Med Biol. 1991 Apr;36(4):439-48
The Monte Carlo computational method was used to model the fluorescence of lead in human kidney. Four different combinations of fluorescing sources and measurement geometry were modeled. 

Measurements of trace elements in vivo.
Chettle DR, Armstrong R, Todd AC, Franklin DM, Scott MC, Somervaille LJ. Basic Life Sci. 1990;55:247-57
The ability to detect quantities of trace elements, such as lead, in human bone while administering the lowest radiation dose possible was explored. Results and measurement performances of various techniques to measure these elements, including L and K X-ray fluorescence and neutron activation, are reviewed.