Page 78 - JSOM Spring 2018

Blood Lead Toxicity Analysis of
Multipurpose Canines and Military Working Dogs

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1*
2*
Paul R. Reid ; Clinton George, DVM, DACVPM ; Christopher M. Byrd, PhD ;
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Laura Miller, LVT ; Stephen J. Lee, PhD ; Alison Motsinger-Reif, PhD ;
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Matthew Breen, PhD, CBiol, FRSB ; Daniel W. Hayduk 8
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ABSTRACT
Special Operations Forces and their accompanying tactical are attributed to lead vaporization from primers containing
multipurpose canines (MPCs) who are involved in repeated lead styphnate and lead-particle generation from jacketed bul-
live-fire exercises and military operations have the potential lets with a soft lead core. Although lead poisoning in humans
for increased blood lead levels and toxicity due to aerosol- is typically defined as having blood lead levels of at least 40μg/
ized and environmental lead debris. Clinical lead-toxicity dL, symptoms are generally more likely to appear only at levels
symptoms can mimic other medical disorders, rendering ac- higher than 50μg/dL to 60μg/dL, with more drastic indications
curate diagnosis more challenging. The objective of this study or permanent damage at levels above 100μg/dL. 3
was to examine baseline lead levels of MPCs exposed to in-
door firing ranges compared with those of nontactical mili- Several studies have sought to identify the levels of lead con-
tary working dogs (MWDs) with limited or no exposure to sidered toxic in canines. Blood lead concentrations above
4–7
the same environment. In the second part of the study, results 40μg/dL can be considered as a marker of lead poisoning in
of a commercially available, human-blood lead testing system dogs. However, blood lead concentrations are not necessarily
were compared with those of a benchtop inductively coupled correlated with severity of the poisoning and we could not
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plasma–mass spectrometry (ICP-MS) analysis technique. find any studies in which clinical symptoms of lead toxicity
Blood samples from 18 MPCs were tested during routine clini- had been reported in animals having levels below 35μg/dL.
cal blood draws, and six samples from a canine group with lim-
ited exposure to environmental lead (nontactical MWDs) were Most civilian-reported cases of elevated lead levels in canines
tested for comparison. There was a high correlation between are from environments in which the local soil and dust contain
results of the commercial blood-testing system compared with unusually high quantities of lead, or from situational circum-
ICP-MS when blood lead levels were higher than 4.0μg/dL. stances such as home renovations or paint removal. 6,7,10 Like
Both testing methods recorded higher blood lead levels in the humans, canines suffering from lead poisoning may exhibit
MPC blood samples than in those of the nontactical MWDs, symptoms such as neurologic abnormalities, muscular convul-
although none of the MPC samples tested contained lead lev- sions, gastrointestinal distress, or death. 7–9
els approaching those at which symptoms of lead toxicity have
previously been reported in animals (i.e., 35μg/dL). Military working dogs (MWDs) are commonly used in patrol
and explosive detection missions and are not persistently ex-
Keywords: heavy metal toxicity; aerosolization; lead, blood posed to training environments in which high levels of lead ex-
toxicity analysis; canines, multipurpose; dogs, military posure may result in toxicity. Conversely, multipurpose canines
working (MPCs) used by SOF personnel supplement the tactical capabil-
ities of the Operators in training and operational environments.
For that reason, MPCs accompany Operators for extensive pe-
riods training at firing ranges and in clearing exercises.
Introduction
One of the primary occupational health risks to Special Op- Materials and Methods
erations Forces (SOF) personnel involved in repeated live-fire
training exercises is lead poisoning, which can result in a po- Blood samples from 18 MPCs and six MWDs were drawn
tentially broad spectrum of symptoms, including insomnia, using standard veterinary methods. Whole-blood samples
cognitive deficits, nausea, malaise, and, in severe cases, enceph- were collected to establish a clinical baseline for blood lead
alopathy. Primary sources of lead exposure at firing ranges levels, and all blood samples were obtained during routine
1,2
*Address correspondence to Paul Reid (paul.r.reid.ctr@mail.mil) or Clint George (clinton7george@gmail.com)
1 Mr Reid is a systems engineering and technical assistance support contractor for Bowhead Systems Management at the Army Research Office,
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Research Triangle Park, NC. He focuses on military working dog research and development. LTC George has been a veterinarian with the US
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Army Special Operations Command since 2001. He is currently a radiology resident at the University of Georgia, Athens, GA. LTC Byrd is the
director of biosciences at the US Army Research Laboratory, Adelphi, MD. He is focusing his efforts on long-term planning and programmatic for
basic research efforts in the biological sciences. MSG Miller is a licensed veterinary technician and was assigned to the US Army Special Opera-
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tions Command, Fort Bragg, NC, from 2005 to 2014. Dr Lee is the chief scientist of the US Army Research Office, and focuses on planning and
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developing the future vision of basic research while maintaining an active research program. Dr Motsinger-Reif is associate professor of statistics,
assistant department head, Department of Statistics, director, Bioinformatics Consulting and Service Core, and director, Statistical Consulting
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Core, North Carolina State University, Raleigh, NC. Dr Breen is professor of genomics and the Oscar J. Fletcher Distinguished professor of com-
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parative oncology genetics, North Carolina State University College of Veterinary Medicine. Mr Hayduk is with the US Army Research Office.
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