Setting up a Sampling Station Estelle Levetin, PhD Disclosure No - - PowerPoint PPT Presentation

▶
setting up a sampling station
SMART_READER_LITE
LIVE PREVIEW

Setting up a Sampling Station Estelle Levetin, PhD Disclosure No - - PowerPoint PPT Presentation

Mar 18, 2024 329 likes •732 views

Session 1202: Basic Aeroallergen Course Setting up a Sampling Station Estelle Levetin, PhD Disclosure No conflicts to disclose Aerobiological Sampling Sampling plan or objective Samplers: Rotorod, Burkard Spore Trap Location

slide-1
SLIDE 1

Session 1202: Basic Aeroallergen Course

Setting up a Sampling Station

Estelle Levetin, PhD

slide-2
SLIDE 2

Disclosure

 No conflicts to disclose

slide-3
SLIDE 3

Aerobiological Sampling

 Sampling plan or objective  Samplers: Rotorod, Burkard Spore Trap  Location  One day head or 7 day head for Burkard  Preparing the samples  Slide Analysis  Identification  Data

slide-4
SLIDE 4

Sampling Objective

 Pollen only or both pollen and spores  Sampling frequency

 7 days a week  5 days a week  3 days a week

 Time commitment

slide-5
SLIDE 5

Rotorod Samplers

slide-6
SLIDE 6

Rotorod Samplers

 Models typically used have retracting rods  Head rotates at 2400 rpm, leading edge of

rod coated with silicon grease

 Pollen and spores impacted on greased

surface

 Generally operated at 10% sampling time  Efficient for pollen and spores >10 mm

slide-7
SLIDE 7

Rotorod Samplers

slide-8
SLIDE 8

Rotorod Analysis

 Collector rods placed in a special adapter

for microscopic examination

 Rods stained with Calberla’s pollen stain  Entire surface of each rod counted unless

pollen/spore load very high (then a subset of the surface is analyzed)

 Atmospheric concentrations determined

slide-9
SLIDE 9

Rotorod Calculations

C = N / V

C is concentration, N is the number of pollen or spores counted

  • n both rods, V is the volume of air sampled by the rods

V = Rod area (m2) x D x p x RPM x t

Rod area = width of rod (1.52* mm = 0.00152* m) x length of the rod (23 mm = 0.023 m) x 2 (both rods), D is the diameter of the Rotorod head (8.5 cm = 0.085 m), RPM is 2400, t is minutes sampled per day With a 5% sampling time (72 min) V = 3.226

Concentration = N/3.226 pollen grains/m3

*NOTE: Width of rods may vary slightly

slide-10
SLIDE 10

Burkard Spore Trap

Advantages

High efficiency down to less than 5 mm

Allows for greater accuracy for small fungal spores such as basidiospores and small ascospores

Time discrimination

Permits analysis for diurnal rhythms

Permanent slides for future reference

slide-11
SLIDE 11

Location

 Roof of a building - ideal 3 to 6 stories

above ground (30 to 60 ft)

 Not close to overhanging vegetation  Air flow not obstructed by nearby

buildings or other structural features

slide-12
SLIDE 12

Parapet around roof requires platform to elevate the orifice above the wall

Telescoping mast elevates sampler above local vegetation.

slide-13
SLIDE 13

Burkard 7-day sampler head

 Standard is the 7-day sampling head  Sampler drum mounted on 7-day clock  Drum moves by orifice at 2 mm per hr  Melenex tape mounted on drum and

greased (Lubriseal, High Vacuum Grease,

  • ther)

 Air is brought in at 10 l/min and impacts on

greased Melenex tape

 Drum changed each week

slide-14
SLIDE 14

Seven Day Sampling Head

slide-15
SLIDE 15

Processing the 7-day drum

 Melenex tape removed from drum  Tape cut into seven 24 hour segments each

48 mm long

 Segments mounted on microscope slides in

10% gelvatol (polyvinyl alcohol) and dried

 Glycerin-jelly mounting medium added and

a 50 mm cover slip

 Mounting medium contains pollen stain -

either basic fuchsin or phenosafarin

slide-16
SLIDE 16

Melenex tape on cutting board

slide-17
SLIDE 17

One-day sampling head

 Alternate head is the 24 hour head  Standard glass microscope slide is

greased and placed on the head

 Alternatively Melenex tape can be fixed

  • n the slide and greased

 Slide is changed daily, carrier

realigned

 Mounting medium with stain and

coverslip are added

slide-18
SLIDE 18

24 hour sampling head

slide-19
SLIDE 19

Outdoor air sample from Tulsa

slide-20
SLIDE 20

Analysis

 Microscopy - 400X for pollen; 1000X

for fungal spores

 Different methods of microscopic

analysis are used to obtain

 Average daily concentration - Single

longitudinal traverse

 Hourly or bihourly concentrations which

can then be averaged to obtain a daily average - 12 transverse traverses

slide-21
SLIDE 21

The Single Longitudinal Traverse Method The Twelve Transverse Traverse Method

Burkard Counting Methods

slide-22
SLIDE 22

Comparison of methods

Single Longitudinal Traverse

Quicker

Produces average daily concentration

Good for routine monitoring

3 or 4 longitudinal traverses can increase accuracy 12 Transverse Traverses

Takes longer

Can determine diurnal rhythm of airborne allergens

All traverses can be averaged to determine average daily concentration

slide-23
SLIDE 23

Conversion to Concentrations

 Microscope counts are entered into a

database such as Excel

 Formulas added to convert counts into

concentrations

 Information needed

Field diameter of objective lens - Variable

Flow rate (10 liters/minute) and exposure time (normally 24 hrs) for a total volume of air sampled of 14.4 m3

slide-24
SLIDE 24

Calculating Concentrations for Single Longitudinal Traverse

 C = Concentration - pollen grains/m3  N = number of pollen counted on traverse  W = Width of entire sample - 14 mm  F = field diameter of objective lens - 0.48 mm  V = total volume of air sampled- 14.4 m3

C = N x W/F x 1/V C = N x 14mm/0.48mm x 1/14.4m3 C = N x 2.025

slide-25
SLIDE 25

Cushing Daily Pollen concentrations Date Cupress Ulmus Ambrosia Artemisia Cheno/AmComposita Cyperacea Poaceae 1-Oct-01 181 4 4 34 13 2-Oct-01 170 8 2 42 17 3-Oct-01 2 284 13 6 48 27 4-Oct-01 269 2 6 21 36 5-Oct-01 6 6 231 48 8 19 8 6-Oct-01 19 19 2 7-Oct-01 57 4 2 4 13 8-Oct-01 164 8 27 17 9-Oct-01 189 6 2 8 10-Oct-01 2 80 8 6 2 8 11-Oct-01 2 27 2 2 2 6 12-Oct-01 4 50 4 17 2 13-Oct-01 19 29 2 6 21 13 14-Oct-01 2 36 2 2 6 4 15-Oct-01 95 63 6 4 15 4

Example of an Excel Spreadsheet with 15 Days of Pollen Data

slide-26
SLIDE 26

Identification

 AAAAI and ACAAI Aeroallergen

courses

 Other aerobiology courses such as the

New Orleans Aeroallergen Course

 Reference slides

 NAB/AAAAI Pollen Slide Library  Reference slides from local specimens  Consult a botanist at a local university

 Identification Manuals

slide-27
SLIDE 27

Identification Manuals

Grant Smith. 2000. Sampling and Identifying Allergenic Pollens and Molds, AAAAI, Milwaukee

R.O. Kapp, How to Know Pollen and Spores - originally published in 1950s - new edition

Richard Weber. 1998. Pollen Identification Ann Allergy Asthma Immunol 80:141–7.

Lacey, Maureen and J. West. 2006. The Air Spora: A Manual for Catching and Identifying Airborne Biological Particles, Springer.

Lewis WH, Vinay P, Zenger VE. 1983. Airborne and Allergenic Pollen of North America. Johns Hopkins University Press, Baltimore, MD.

Aeroallergen Photo Library, Steve Kagan, http://allernet.net/

slide-28
SLIDE 28

Essential Reference

 Grant Smith’s

Sampling and Identifying Allergenic Pollen and Molds

slide-29
SLIDE 29

Sample Pages

slide-30
SLIDE 30

http://allernet.net/

slide-31
SLIDE 31
slide-32
SLIDE 32

How the data can be used

 Average daily concentrations can be

graphed to look at the seasonal and yearly pollen levels

 Develop regional pollen calendar  Data can be compared with patient

symptoms, peak flow readings, office visits, emergency room visits

 Prepare for peak seasons - staffing, etc

slide-33
SLIDE 33

Average Daily concentration of Airborne Pollen in Tulsa - 2008

500 1000 1500 2000 2500 3000 J F M A M J J A S O N D Pollen grains/m 3

slide-34
SLIDE 34

Airborne Ambrosia pollen in Tulsa Fall 1999

100 200 300 400 500 600 700 8/15 8/29 9/12 9/26 10/10 10/24 Pollen grains/m3

slide-35
SLIDE 35

Multiple Years of Data

 Data from several years can be

averaged to produce a graph of the pollen season

 Smoothing techniques such as 5 day

running mean can be used to generate a smoother curve and better estimate

  • f the typical peak period
slide-36
SLIDE 36

Mean airborne Ambrosia pollen in Tulsa: 1987-2007

100 200 300 400 500 600 1 5

  • A

u g 2 2

  • A

u g 2 9

  • A

u g 5

  • S

e p 1 2

  • S

e p 1 9

  • S

e p 2 6

  • S

e p 3

  • O

c t 1

  • O

c t 1 7

  • O

c t 2 4

  • O

c t 3 1

  • O

c t

slide-37
SLIDE 37

Five day running mean of airborne Ambrosia pollen in Tulsa

100 200 300 400 500 600 700 8/15 8/29 9/12 9/26 10/10 10/24 Pollen grains/m3

Peak on or about Sept 10

slide-38
SLIDE 38

Conclusion

 Air sampling allows the allergist to get

a first hand understanding of the local aeroallergens, their concentration, and season occurrence

 Several years of sampling will allow for

the development of a pollen calendar which can benefit the physician and his or her patients

slide-39
SLIDE 39

Additional references

Gregory, P. H. 1973. The Microbiology of the Atmosphere, 2nd ed., Halstead Press, NY.

Lacey, J and J. Venette. 1995. Outdoor Air Sampling Techniques. in Bioaerosols Handbook, C.S. Cox and C.M.Wathes, ed., Lewis Publishers, Boca Raton, FL.

Levetin E. and Horner WE. Fungal Aerobiology: Exposure and Measurement, in “Fungal Allergy and Pathogenicity”, ed by Brittenbach, Crameri,

  • Lehrer. Krager, Basel. 2002; 81: 10-27.

Weber, R (ed). 2003. Immunology and Allergy Clinics of North America. Vol 23 (3) Aerobiology