All ages study of blood-lead and bone-lead in urban Toronto: lessons learned from a collaborative st...
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All ages study of blood-lead and bone-lead in urban Toronto: lessons learned from a collaborative study. T Arbuckle, F McNeill, M Inskip , D Chettle, WI Manton, M Fisher, N Healey, R Bray, L. Marro

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All ages study of blood-lead and bone-lead in urban Toronto: lessons learned from a collaborative study

T Arbuckle, F McNeill, M Inskip, D Chettle, WI Manton, M Fisher, N Healey, R Bray, L. Marro

Main funding: Health Canada, [Chemicals Surveillance Bureau, Environmental and Radiation Health Sciences Directorate]


Co investigators and groups

Co-investigators and groups lessons learned from a collaborative study

Health Canada

Tye Arbuckle (Co -PI)

Mandy Fisher

Mike Inskip (now with McMaster University)

Norm Healey (now with Azimuth Consulting Group)

Leonora Marro

Department of Health Physics, McMaster Univ

David Chettle

Fiona McNeill (Co-PI)

SepidehBehinaein (Ph.D student)

University of Texas at Dallas

William Manton

Hospital coordinating centre– St Joseph’s Hospital, Toronto

Jessica Tyrwhitt

Toronto Public Health

Riina Bray


Talk outline
Talk outline lessons learned from a collaborative study

  • Goals, study design and context

  • Techniques used

  • Results so far …..

  • Lessons learned

  • Discussion / summary


Study goals
Study goals lessons learned from a collaborative study

The first Canadian study that we are aware of which attempts to measure bone Pb in young children. The pilot study goals were to demonstrate:

  • the feasibility of including in vivo XRF measurements of Pb in bone for young children in future surveys [like the ‘Canadian Health Measures Survey’]

  • the feasibility of 1) remote bone Pb measurements;

  • 2) partnership with a local community health centre for recruitment and subject measurement;

  • 3) quantification of serum Pb concentrations in environmentally exposed subjects

  • 4) recruitment of childhood subjects for venous blood sampling;

  • 5) development and delivery of appropriate risk communication materials.


Testing and recruitment success total 263 272 participants
Testing and recruitment success lessons learned from a collaborative studyTOTAL: 263/272 Participants

Age ExpectedTested

Males FemalesMales Females

1 to 5 10 10 10 6

6 to 10 23 20 23 16

11 to 19 23 20 23 20

20 to 35 21 25 21 25

36 to 50 25 29 25 29

51 to 64 21 24 21 24

65 to 85 10 11 9 11

Total 133 139132 131

  • 1 participant cancelled; 2 participants did not assent to participate in the study;

  • 5 appointments were cancelled - equipment malfunction (participants rescheduled)


Methods techniques for success plans and reality 1
Methods / techniques for success: lessons learned from a collaborative studyplans and reality #1

  • Very effective (and persistent) hospital coordinator for reaching potential volunteers / scheduling visits

  • Patient-friendly & very skilled child phlebotomist and measuring staff and well-designed procedures for family groups being measured + questionnaire time allowed.

  • Financial ($50) incentive

  • YES

  • YES – but early-on suspected a brief contamination event; Used TV games and books & adult distractions to keep children engaged

  • YES – but poorer participation rate by younggirls vs the boys


Methods techniques for success plans and reality 2
Methods / techniques for success: lessons learned from a collaborative studyplans and reality # 2

  • Training for obtaining serum samples (Class-100 clean room, gloves etc., centrifuge on site) and pre-cleaned sample tubes, sample dispatch processes.

  • Choice of experienced analytical lab for Pb

  • Communications with volunteers about health risk by Toronto Public Health personnel very familiar with PbB exposure routes in homes.

  • YES – but Couriers lost one batch of samples

  • YES: …although challenges.

  • Low blood lead values did not necessitate many home visits.


1 st blood sample venipuncture for whole blood and hematocrit
1 lessons learned from a collaborative studyst blood sample - venipuncture for:whole blood and hematocrit

Bluetop Vacutainer

tube

Place a drop of blood sample onto slide and draw

into a capillary tube.  The capillary tube is then spun to

separate the red blood cells from the plasma at which

time a Hematocrit value can then be measured. 


2 nd sample venipuncture for blood serum sample
2 lessons learned from a collaborative studynd sample : Venipuncture for:blood serum sample

to measure a person’s Hematocrit is by

  • Use butterfly +syringe to slowly collect

  • 5ml blood. Remove butterfly tip, leave sample stand 20 minutes.

  • NB The following are done in CLEAN BOX

  • Slowly transfer blood to centrifuge tube*

  • Spin down using bench centrifuge

  • Decant plasma (Special tip*) into Teflon jar*

  • Record patient I.D. against jar number

  • Tighten lid & freeze sample

  • * provided


Why is use of a hepa clean box class 100 air important
Why is use of a HEPA Clean Box lessons learned from a collaborative study(Class-100 air) important?

  • Differences: at least 100 times (!) less Pb is present in Plasma vs. whole blood

    • E.g., If PbB = 1 ug/dL, plasma Pb = 0.01 ug/dL or 100 pg/ml

  • Where things can get contaminated

    • Pb on airborne particles

    • Pb on hands or any surfaces.

    • One speck of dust enough to contaminate sample

    • Pb can also leach-out from plastics


Blood collection protocol
Blood collection protocol lessons learned from a collaborative study

  • Blood volume: the phlebotomist must do their best to obtain as much as possible - up to the desired amount of 5mL.

  • For the serum sample, the tube is left to stand for 20 minutes

  • After centrifuging, a dedicated pipeter is used to transfer plasma; when not in use, it is kept in the clean box as the photo shows (hanging).

  • The rack of pre-cleaned 15 mL teflon jars and the centrifuge tubes must never leave the clean box.

  • The transfer of the supernatant plasma to the tubes must be done in the box.


Treatment of sample when taken
Treatment of sample when taken lessons learned from a collaborative study


Benchtop centrifuges for plasma hematocrit
Benchtop centrifuges for plasma / hematocrit lessons learned from a collaborative study


Results blood lead vs age male female
Results: Blood lead vs age ( lessons learned from a collaborative study*male / *female)


Systematic representation of vascular organisation lessons learned from a collaborative study

in the diaphysis of a long-bone (From Mayo Foundation

for Medical Education and Research)


Summary
Summary lessons learned from a collaborative study

  • Blood lead levels were lower than expected …but in the range found for the CHMS survey; Lead levels in serum required special attention for analysis

  • Serum lead levels were so low that the Texas laboratory had to develop a new technique to measure them.

  • Special attention to training of collection staff was a good investment (and critically important for obtaining reliable data).

  • Bone lead data were successfully obtained for young children by in vivo XRF; Themethod is being further evaluated as a tool for measuring children’s skeletal burden.

  • A multi-disciplinary team approach was considered essential for this study.


Summary 2
Summary (2) lessons learned from a collaborative study

  • Analysis of data continues: e.g.:

    • Bone/PbB/serum data

    • Questionnaire results related to values

    • Additional information on isotope ratios in blood samples & possible source of environmental Pb


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