Endotoxins: An indoor air Endotoxins: An indoor air and settled dust survey.and settled dust survey.

J. Dobranic, Ph.D.* & S. Cappuccio, J. Dobranic, Ph.D.* & S. Cappuccio, B.Sc.B.Sc.

EMSL Analytical, Inc.EMSL Analytical, Inc.www.emsl.comwww.emsl.com

Tel: 800-220-3675Tel: 800-220-3675Email: Email: jdobranic@emsl.comjdobranic@emsl.com

IntroductionIntroduction

• Evaluate and compare fungal contamination Evaluate and compare fungal contamination in air and surface samples with endotoxin in in air and surface samples with endotoxin in accumulated dust.accumulated dust.

• Dust may represent cumulative exposure to Dust may represent cumulative exposure to endotoxin.endotoxin.

EndotoxinEndotoxin

• Pyrogenic, cell wall component Pyrogenic, cell wall component (lipopolysaccharide) of Gram-negative (lipopolysaccharide) of Gram-negative bacteria.bacteria.

• Heat-stableHeat-stable

EndotoxinEndotoxin

• Elevated airborne concentrations are Elevated airborne concentrations are prevalent in sewage treatment plantsprevalent in sewage treatment plants

• swine operations swine operations • cotton textile millscotton textile mills• poultry housespoultry houses• water damaged water damaged

buildingsbuildings

Health EffectsHealth Effects

• Produces airway inflammation (wheezing)Produces airway inflammation (wheezing)

• Associated with increased severity of child Associated with increased severity of child and adult asthmaand adult asthma

• Exposure during childhood may reduce Exposure during childhood may reduce allergic responses later in lifeallergic responses later in life

• Cause of Humidifier FeverCause of Humidifier Fever

Materials and MethodsMaterials and Methods

• Various fungal samples based on IAQ Various fungal samples based on IAQ investigation.investigation.– Spore traps and surface samplesSpore traps and surface samples

Materials & MethodsMaterials & Methods

• 12 homes sampled in NJ & PA.12 homes sampled in NJ & PA.

• 3 endotoxin samples collected in each 3 endotoxin samples collected in each dwellingdwelling– Kitchen floor, Sofa, Living Room floor, Bedroom Kitchen floor, Sofa, Living Room floor, Bedroom

floor, Bedroom bed, basement.floor, Bedroom bed, basement.

Materials & MethodsMaterials & Methods

• Specifications: Specifications: 0.45µm Polycarbonate Filter 0.45µm Polycarbonate Filter

37mm Styrene Housing 37mm Styrene Housing

Sterilized by Irradiation Sterilized by Irradiation

Endotoxin Free Endotoxin Free

• Sift dust through 350 micron sieveSift dust through 350 micron sieve• Kinetic Chromogenic Kinetic Chromogenic LimulusLimulus

amoebocyte lysate (LAL) assay (EU – amoebocyte lysate (LAL) assay (EU – endotoxin units)endotoxin units)

Horseshoe Crab Harvest

Blood Collection

ResultsResults

• Surface sample:Surface sample:– 9 out of 12 homes had visible mould 9 out of 12 homes had visible mould

growth inside (growth inside (AspergillusAspergillus, , ChaetomiumChaetomium, , PenicilliumPenicillium, and , and StachybotrysStachybotrys))

• Spore traps:Spore traps:– 8 out of 12 had > indoor spore counts vs 8 out of 12 had > indoor spore counts vs

outdoorsoutdoors

Results

• Endotoxin:Endotoxin:– Mouldy: 0.1-263.6 EU/mg dustMouldy: 0.1-263.6 EU/mg dust

– Non-Mouldy: 0.5-38.5 EU/mg dustNon-Mouldy: 0.5-38.5 EU/mg dust

• Published range is 11-100 EU/mg dustPublished range is 11-100 EU/mg dust

ResultsComparison of Endotoxin Levels in Dust in Mouldy and Non-

mouldy Homes

0

2

4

6

8

10

12

Mouldy Non-mouldy

Type of Home

En

do

toxi

n V

alu

es (

EU

per

mg

d

ust

)

Geo Mean

Results

Relationship Between Dust Endotoxin Levels and Mould Spore Counts

y = -26.646x + 6641.3

R2 = 0.0398

-5000

0

5000

10000

15000

20000

25000

0 50 100 150 200 250 300

Endotoxin Levels in Household Dust (EU/mg)

Ma

xim

um

To

tal S

po

res

(co

un

ts/m

3)

ConclusionsConclusions• Mouldiness in homes was not a good predictor Mouldiness in homes was not a good predictor

of endotoxin levels. of endotoxin levels.

• Similar conclusion in published studies Similar conclusion in published studies comparing endotoxin in air with mouldiness.comparing endotoxin in air with mouldiness.

• Suspicion of GNB contamination requires Suspicion of GNB contamination requires directed endotoxin testing.directed endotoxin testing.

Endotoxin Predictors in LiteratureEndotoxin Predictors in Literature

• Positively correlated with presence of a Positively correlated with presence of a dog or past presence of a dog.dog or past presence of a dog.

• Positively correlated with use Positively correlated with use of a cool-mist humidifierof a cool-mist humidifier

• Negatively correlated with use Negatively correlated with use of a dehumidifier.of a dehumidifier.

AcknowledgementsAcknowledgements

• Marc Leftwich and Bob Woodward at AMT Marc Leftwich and Bob Woodward at AMT Mold Testing in PA.Mold Testing in PA.

• EMSL’s clients for participation.EMSL’s clients for participation.

Contact InformationContact Information

• Jason Dobranic, Ph.D.Jason Dobranic, Ph.D.– EMSL Analytical, Inc.EMSL Analytical, Inc.– 107 Haddon Ave. Westmont, NJ 08108107 Haddon Ave. Westmont, NJ 08108– Tel: 800-220-3675Tel: 800-220-3675– Email: jdobranic@emsl.comEmail: jdobranic@emsl.com