1. Introduction to Lead Lab

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1.  Introduction to Lead Lab Powered By Docstoc
					Instrumental Methods of Analysis
1. Introduction
 1. Writing Intensive
     1. Rewrites are Required
     2. Large Amount of Excel Data Management
 2. Work
     1. Individual
          1. Work Log
          2. Own Sample
          3. Exams
          4. Lab Book pages
     2. Group
          1. Division and Attribution of Labor (Accountability)
          2. Reports
          3. Calibration Curves
 3. Single Analyte (Skill Development and Cross Comparison Methods)
     1. Overlapping Themes
          1. Statistics/Sampling
          2. Solution Chemistry
          3. EDTA
          4. Isotopes
          5. Phase Separations
Instrumental Methods of Analysis
1. Introduction

   1. Writing Intensive
   2. Work
   3. Single Analyte
   4. Problem Based
       • What is best method for lead analysis?
       • What is best method for This particular sample?
   5. Ethics and Service Learning
       1. How do we know?
       2. Critical Thinking
       Confusion            Electronics, Spectroscopy,             Confusion
                        Electrochemistry, Chromatography

                       “Too much from instructor” information




                                                         7 different analytes
                                                         7 different methods
           Iodide                    Chromium &
        Electrolysis                permanganate          How do we select
                                       UV-Vis             Or compare methods/
                                                          Instruments?
                    Methanol Gas
                   Chromatography         Quinine
   Fluoride                            Fluorescence
Ion Selective                                              DMSO
  Electrode                                               Infrared
                         Cu Graphite
                                                        Spectroscopy
                          Furnace
                           Atomic
                         Absorption
Figures of Merit Theme      Choose Method:                               Knowledge
                            Cross Compare/measure LOD
Pb Limit of detection?
Pb Linear range?
Pb Selectivity?
Pb Signal/Noise?                                          Role of solution pH important
                              Calcein Blue
                            Pb Fluorescence
                              Quenching
             Pb Anodic
             Stripping                     Pb Dithizone
            Voltammetry                      UV-Vis                Pb Atomic
                                                                   Absorption
                         207Pbin EDTA by
                           proton NMR
                                           Pb Ion Selective
     Tetraethyl 207Pb MS                       Electrode

                                                             EDTA Pb HPLC
                           Pb EDTA Infrared
                            Spectroscopy
Week                 Topic                            “Lab”                Concept
                                                                     Stat Chem Isotope Ethics
1      Pb & Society; Statistics and Ethics    Pototo populations       x                      x
2      Signals & Noise; LOD                   Analog & Digital filters x
3      Relevant Chemistry; Exam I             ISE & Pb(OH)2                 x
4      Intro Spectroscopy                     IR & UV-Vis                   x
5      Molecular Spectroscopy                IR & UV-Vis                    x
6      Fluorescence and AA                   Fluorescence and FAA x         x
7      AA and Vibrational, Exam II           Fluorescence and FAA x        x
8      Break, NMR                            Break
9      NMR, Off campus sampling              NMR, ASV                       x     x       x
10     MS,                                   NMR, ASV                       x     x       x
11     Intro Electrochem., Select Method      sample prep        x     x              x
12     Potentiometry,                        sample analysis x                    x
13     ASV, Take home exam III               ICP-MS, GC                     x     x
14     Separations                            ICP-MS, GC                    x     x
15     Separations                            How do we know? Ethics x                    x
Why Lead?
  Health
Same size,
Shape, chemistry
Different
Orbitals,
Different total
Number of electrons
Warren et al, TIBS, 1998, 23, 217
Current
measurements
no longer
rely on zinc
protoporphyrin
as PbB effects
on fetal development
can be detected
at values of PbB
<5 ug/dL
An estimated 40% of lead in blood plasma bound to ALAD
   Wetmur, 1994




         ALAD dehydratase with lead binding site
Enhanced ALA concentration leads
to tautomers which easily form
radicals which may attack the cell
wall - leading to early cell death. Heme dies about 20% earlier
         Hammond and Dietrich, 1990
                                      Because lead affected ALAD
                                      resulting in overproduction of ALA
                                      ALA may also affect the function
                                      of GABA but a close similarity
                                      in molecular structure




GABA controls leaf tip growth, and brain development. Function
changes with time, so growing tips and infants differentially affected
from adults
Herlenius and Lagercrantz, 2001
Ben-Ari1, 2001

Certain portions of the brain more greatly affected:
prefrontal cortex: problem solving
hippocampus (memory)
cerebellum (motor coordination, body movement, posture and balance)
Why Lead?
  Everywhere
Lead as an
ore in the earth
relatively
benign
Human activity
distributes
lead into the
environment
Modern major uses

1. Pigments
2. Leaded Gasoline
3. Munitions
                           Eliminating Childhood Lead Poisoning:
                           A Federal Strategy Targeting Lead Pain Hazards, Feb. 2000




Decade    Thousand     Thousand          Millions          White lead         Remaining
          Tons         Tons              Occupied          per unit           lead
          white lead    red lead         Units             (pounds)           thousands
                       (litharge)                                             tons
1914-23   1340         0                 24.35             110                413
1920-29   1307         356               29.91             87                 184
1930-39   737          421               34.86             42                 104
1940-49   476          1189              42.83             22                 72
1950-59   196          816               43.02             7                  37
1960-69   82           781               63.45             3                  20
1970-79   29           625               80.39             1                  841
Other Ecosytem Impacts of Lead



                                         To air



               Mine                                                                 Deposit
                                                       Deposit                      elsewhere
                                                       locally    Fishing sinkers
                                                                  & shot
                      incinerate

                                                  Sewage
               ash     reclaim                    sludge
Cement block
                                                    landfill

                                            Flow to groundwater
                            fertilizer                                      Bottom sludge

                      Plant uptake         groundwater
2009 Class Project
Growing Scientists                 S. 1994
20 5th graders map park soil lead
   Northwest Incinerator             F 1994
    Austin homes: Yard Soil Lead
      Northwest Incinerator
                                        F 1995
       Grid map
      National     House Dust                     F 1996
      Award for Uptown 5th graders sample and tour
      The Class labs       House Dust                    F 1997
                          Little village Boys and Girls Club
                          (failed) Northwest Incinerator        F 1998
                                    Tight grid and isotopes

                                      Bethel New Life: Brownfield        F. 1999
                                      Soil sampling
                                            Orozco School: House Dust          F 2000
                                             ACS Pullman: White Lead Factory F 2001
                                             Mtg
                                                     House Dust                F 2002
                                             poster
                                                    West Pullman White Lead factory

                                                 S 2008
                                                 Lead in Toys
                                                 Evanston Childcare       Alanah Fitch afitch@luc.edu
                  Lead Elimination Action Drive
                  West-side Alliance for a Safe Environment (WASTE)
                  Center for Neighborhood Technology
                  Austin Neighborhood Council




Homes         Municipal Waste Incinerator
        Pb?
                                        Incinerator 1994, 1995, 1998
   Wind




Background                                    Decreasing amts
Soil lead    “Shadow” depends on   Largest deposition
             Stack height          Is here
                                    Incinerator 1994, 1995, 1998
           Control


                     Students meet with
sampling
                     elderly ladies who let
                     them sample soils.
                     The ladies discuss their
                     concerns.




                       Incinerator 1994, 1995, 1998
Front               Soil Lead in parts per million (ppm)




   1040

              440                            187

        4915 W. Kamerling          4822 W. Potomac           4833 W. Crystal
Back




                                                                              1800
                            1850      1385
  1431              231             250        150                      372
   garage
                                                     Incinerator 1994, 1995, 1998
Comparison homes, 17 mile away




                       1133      2620

      2808      2900             3067
                                                      1538

                         700                    439


     6613 N. Ashland                    6729 N. Ashland
             BRICK                          FRAME



                                          Incinerator 1994, 1995, 1998
            Second year: Resample with respect to
            the wind; also allowing for up and down wind
            comparisons. Wins a National Award.




Luke later goes to Croatia
On UN project on
Lead dispersion by
gasoline


                                             Incinerator 1994, 1995, 1998
                                                                              This data presented
                                                          North               To Mayor’s advisory
Wind Pattern
                                                                              council
                                32                    101
                                                                              Class final: enter
                                                                              Busch National Env.
                                      23
                               12                                             Award competition –
                                                                              Place third
                                                                Chicago
                              89 82



                                           Orr High
                               1210 123




                                           School
                          346 546                                                           644 m




                                                      Pulaski
Demolished lot            15
                              320
                 Cicero




                           42
                                                                Washington
                          0




                                                                             Incinerator 1994, 1995, 1998
            14

            12

            10
                       > 0.5 mile from incinerator
Frequency




            8

            6
                       < 0.5 mile from incinerator
            4

            2

            0


               50
               50
               50
               50
                0
                0
                0
                0
                0
                0
                0
                0
                0
                0
              10
              20
              30
              40
              50
              60
              70
              80
              90
             10
             11
             12
             13
                 PPM Soil Lead

                                   Incinerator 1994, 1995, 1998
   Wind




Background                                    Decreasing amts
Soil lead    “Shadow” depends on
             Stack height          Largest deposition
                                   Is here
                                    Incinerator 1994, 1995, 1998
Last time: we finally set up an experiment worthy of an
An air pollution expert

                                                    NE
                           NNE
                  N
             61                                           ENE
              46

                  30                                              E
                      15

                           0

                           -15

                               -30

                                 -46                             61   SE
                                                          46
                                     -61             30
                                               15
                                           0
                                                               Incinerator 1994, 1995, 1998
Across
1      the system of pipes and other apparatus for conveying water,
       liquid wastes, etc., as in a building
3.     the fluid that circulates and carries oxygen throughout the human
       body
4.      being placed at risk
8      the quality of degree of being toxic or harmful to plants or
       animal life
9.     the introduction of harmful substances or products into the
       environment
10.    a mixture of pigment and liquid
12.     food, eating healthy
14.    a pain located in the head
15.    the age group affected most by lead poisoning
17.    President on the $20 bill
18.    a transparent, odorless, tasteless liquid, a compound of hydrogen
       and oxygen, H20, that constitutes rain, oceans, lakes, rivers, etc.
19.    . to take ill through eating

Down
2.   a heavy, comparatively soft, malleable, bluish-gray metal. A
     toxic metal, that has been widely used in paints, plumbing and
     fixtures, and in some water supply service lines
3.   composer thought to have had lead poisoning
5.   the portion of the earth's surface consisting of dirt
6.   the air, water, minerals, organisms, and all other external factors
     surrounding and affecting a given organism at any time
7.   dry particle of earth
10.  a table illustrating the periodic system, in which the chemical
     elements are shown in related groups
11.  . the process of preparing the samples by breaking down the baby
     wipes into a substance suitable testing
13.  a silver-white divalent metal found in limestone, chalk, milk
16.  the science that deals with the composition and properties of
     substances and various elementary forms of matter
2009 – Brainstorm on
Projects
   Short list by next week
Health Effects of Lead
Inhalation depends upon
the particle size.

This data is for
humans
               Dissolution of lead carbonate particles in
               simulated gastric juices as a function of particle size




For birds, the uptake will depend upon the pH and grinding action in
the gizzard. For ruminants, the uptake will depend upon the lifetime
in the digestive organs
94-99% of lead attached to
external surfaces of
erythrocytes

1-6% lead in plasma,
of which 99% attached to
proteins


~0.1 to 0.6 % of lead is
as the free cation
Recognition will be similar for various species
                                                     Active
              Ca        Ba                           uptake of
                                                     calcium,
                                                     apparently
                                                     to lesser
                                                     extent other
                                                     divalent similar
                                                     sized cations,
                                                     including
                                                     lead.




Calcium uptake is controlled by Vitamin D and growth regulators
parathyroid hormone (PTH)
Calcium is stored to the endoplasmic reticulum, lead will also
go there
Basophilic Stippling of Dog Blood caused by nucleation of
ribonucleoproteins in presence of lead




High lead causes deformation of blood cells and shorter lifetime of
the red blood cell.
Double whammy - production is also affected
Current
measurements
no longer
rely on zinc
protoporphyrin
as PbB effects
on fetal development
can be detected
at values of PbB
<5 ug/dL
                                                               1 hour
                                                               after
                                                               exposure
                                                               lead is
                                                               found
                                                               within the
                                                               kidneys,
                                                               because
                                                               kidneys
                                                               are
                                                               monitoring
                                                               blood
                                                               calcium
                                                               levels via
                                                               the
Renal biopsy of a 28 year old shipwrecker. Dense               glomerular
intranuclear inclusion body is characterized by a fibrillary   filtration
outer margin; Cramer, Goyer et al. Brit. J. Indust. Med., 1984 rate
Renal biopsy of a 28 year old shipwrecker. Interstitial fibrosis
with atrophy of some tubular lining cells; Cramer, Goyer et al.
Brit. J. Indust. Med., 1984
Damage to kidney results in
  hypertension
  gout
Thomas Rowlandson’s The King’s Bath
Cruikshank’s gout
Calcium is closely monitored by kidney because it plays a large
role in various signalling processes
           Calcium bound to calmodulin
C. Yang, G. S. Jas, K. Kuczera, J. Biomolecular Structural Dynamics,
2001, 19,257-271
Lead double whammy                     Calcium serves as a
       1. Low lead turns on triggers   trigger for muscle
       2. Hi lead turns off triggers   contractions:
                                       troponin C
Colic is a form of muscle spasming
So are the “shakes”
   Lead, like calcium, is deposited to the hard tissues
   Implications for the Trophic level of lead in the environment




Osteocalcin (bone Gla protein (BGP)) controls calcium deposition
and is affected by lead: weaker bones for affected individuals
Longitudinal Section & Cross Section of Bone
                                Trabecular
                                Bone




      Compact Bone
Seizures can result from lead due to Ca triggers of the synapses
Other Irrelevant Information that
Is mildly amusing/interesting on Lead
~5,000 years ago
Cuppellation
Begins


                             886oC


               -0.2oC (Au)
               230oC (Ag)




                             Purity of Pb: 99.9% achieved

				
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