Mold Litigation Perspectives - PowerPoint PPT Presentation

Mold litigation perspectives
1 / 55

  • Uploaded on
  • Presentation posted in: General

Forensic Analytical. Mold Litigation Perspectives. Presented by: Ben Kollmeyer, MPH, CIH Forensic Analytical Consulting Services CIHC – December 5, 2006. Overview. The Case of the Phantom Mold Common Issues PCR: A Better Mousetrap?.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

Download Presentationdownload

Mold Litigation Perspectives

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Mold litigation perspectives

Forensic Analytical

Mold Litigation Perspectives

Presented by:

Ben Kollmeyer, MPH, CIH

Forensic Analytical Consulting Services

CIHC – December 5, 2006



  • The Case of the Phantom Mold

  • Common Issues

  • PCR: A Better Mousetrap?

The case of the phantom mold carpet microvacuum results in a litigated manner

The Case of the Phantom Mold:Carpet Microvacuum Results in a Litigated Manner



  • Teacher alleges various injuries caused by environmental conditions at a school.

  • Suit against school dismissed (worker’s compensation as exclusive remedy).

  • Focus shifts to school builders and suppliers.

  • Focus shifts to mold and mycotoxins.

Environmental setting

Environmental Setting

  • School set in an arid climate.

  • Rooms arranged around a central quad with exterior entrances.

  • Teacher predominately spent time in two classrooms, 4 & 7. Predominately 7.

  • Room 4: slab on grade, sticks & bricks.

  • Room 7: modular at grade w/ crawlspace.

  • Focus of claims is on room 7.

Environmental data

Environmental Data

  • Visual observation by three different environmental consultants.

  • Air sampling by one consultant.

  • Microvacuum sampling by two consultants within 6 months of each other.

  • Tapelift and swab samples by two consultants.

Visual findings summary

Visual Findings Summary

  • Room 7

    • Standing water and biological growth in sub-grade crawlspace.

    • Evidence of exterior surface moisture and intrusion into entry.

    • No elevated moisture in carpet.

    • No visible mold.

  • Room 4

    • Mold at sink separator.

    • Mold behind baseboard.

Mold litigation perspectives

Room 7

Mold litigation perspectives

Room 4

Swab and tapelift samples

Swab and Tapelift Samples

  • Confirm visual observations.

  • Others do not reveal elevated levels.

  • General agreement among consultants.

Air sampling summary

Air Sampling Summary

  • 2 locations in each room.

  • Viable and non-viable samples.

  • Variety of rooms other than 7 & 4.

  • 4 outdoor control controls.

  • Results do not show elevations in 4 or 7.

    • Generally lower than outdoors.

    • No different than other rooms.

  • General agreement among consultants.

Microvacuum results

Microvacuum Results

  • Consultant #1

    • cfu/100cm2

    • 8 samples from room 7.

    • 6 samples from room 4.

  • Consultant #2

    • cfu/g

    • 3 samples from room 7.

    • 3 samples from room 4.

Carpet dust studies

Carpet Dust Studies

  • Chao, et al (Harvard Study)

    • Mycopathologia 154:93-106, 2001

  • Randomly selected office buildings.

  • Most strongly correlated w/ age of carpet:

    • Yeast

    • Coelomycetes

    • Aureobasidium

    • Non-sporulating

Carpet dust studies1

Carpet Dust Studies

  • Chew, et al

    • Allergy 58:13-20, 2003

  • Randomly selected homes.

  • Most common:

    • Non-sporulating, Penicillium, Yeast

  • More prevalent in dust than air:

    • Yeast, Eurotium, A. versicolor

Carpet dust studies2

Carpet Dust Studies

  • Horner, et al.

    • Applied & Environmental Microbiology 70:6394-6400, 2004

  • Non-problem homes.

  • Most common:

    • Cladosporium

    • Yeast

    • Penicillium

Carpet dust studies3

Carpet Dust Studies

  • Hicks, et al.

    • JOEH 2:481-492, 2005

  • Non-problem homes.

  • Most common, high traffic:

    • Cladosporium, Yeast, Penicillium, Aureobasidium

  • Most common, low traffic:

    • Cladosporium, Penicillium, Yeast

The positions

The Positions

  • Plaintiff focused on the presence of elevated levels of yeast with moisture under the building as the cause.

  • Defense found results to be typical of carpets and foot traffic patterns. Focused on moist grass outside of classrooms and lack of differences in sampling results between the two types of construction.

The outcome

The Outcome

  • It settled before trial (of course).

  • Both sides equally unhappy (supposedly).

Interpretation of mvac results

Interpretation of Mvac Results

  • Quantitative….less valuable

    • Extremely variable. Highly dependent upon how sample is collected.

    • Commonly used numerical values (i.e., 100K cfu/g) not very reliable.

    • Focus on comparative samples.

Interpretation of mvac results1

Interpretation of Mvac Results

  • Qualitative….more valuable

    • Compare to genera/species commonly found in non-problem buildings.

    • Compare to known growth reservoirs.

  • Visual….most valuable

    • If there is mold exposure, show me the mold.

Common issues

Common Issues

Common issues1


Common Issues

  • Mold is Gold?

  • Investigative Approach:

  • Specificity of Repair Recommendations:

    • “Remove ?? inches beyond affected materials.”

    • Methods…containment, PPE, etc.

    • DT protocols.


Common issues2


100% = “YES” “MAYBE” 0% = “NO”

Common Issues

  • Linkages to Causal Factors

  • Linkages to Health Effects

  • Reasonable Degree of Scientific Certainty

Common issues3

Common Issues

  • What Does the Future Hold?

    • “Damp Indoor Spaces & Health”

      • fungal spores? materials? mycotoxins? mVOCs?

      • bacteria?

      • dust mites?

      • allergens?

      • moisture?

      • sick people with lawyers?

Mold litigation perspectives

PCR:A Better Mousetrap?

Mold sampling methods

Mold Sampling Methods

  • Total airborne spores – “nonviable”

  • Viable airborne spores – “culturable”

  • Airborne mold spore equivalents – genetic material – PCR method

Nonviable spore counting

Nonviable Spore Counting

  • Limited ID at genus level only

    • Genera groupings become surrogates for individual species.

    • May be comparing apples to oranges…missing differences between species.

  • Short sampling times.

  • Fast TAT (hours to days).

  • Relatively inexpensive.

Viable culturing

Viable Culturing

  • Can provide identification to the species level, but is frequently too expensive and time consuming.

  • Viable mold spores only, misses non-viable spores. Furthermore, “viable” may not be “culturable”.

  • Short sampling time.

  • Long turn-around time.

  • Can be quite expensive to get species.

  • “Viable” may not be “culturable”

  • Long TAT

Pcr analysis

PCR Analysis

  • 24-hour speciation of viable and non-viable spores.

  • Instrument-based method with less subjectivity and more conducive to quality assurance procedures.

  • Sampling time constraints lifted, allowing for longer duration samples (e.g., 8-hour).

  • Must target a species or panel for analysis.

  • Optical microscopy and molecular genetics differ taxonomically.

Mold analysis methods

Mold Analysis Methods

Spore Traps



Putting pcr to use

Putting PCR to Use

  • Characterize Sources

    • Non-viable assessment to ID key genera.

    • Collect a representative dust/bulk sample.

  • Non-viable methods to begin focusing panel. PCR analysis of source sample to see what responds.

  • Selection of “indicator” species.

  • Targeted analysis of long-term air samples.

Lessons from the past pcm

Lessons from the Past: PCM

  • Surrogate Method (PCM): counts relatively large airborne fibers instead of airborne asbestos fibers, which are often too short and/or too thin ever to be counted by PCM

  • Surrogate Standard (PCM): Clearance at levels below 0.01 f/cc by PCM. Nearly assured not to have actually assessed airborne asbestos

Lessons from the past tem

Lessons from the Past: TEM

  • “The TEM method gives the most complete information on airborne asbestos: it can distinguish asbestos from other fibers and also is able to detect very thin fibers. However, it is expensive and time-consuming. TEM is not readily available.”– The EPA Purple Book, 1985

Pcr looking ahead

PCR: Looking Ahead

  • Back to IH Basics

    • 8-hour TWA sampling

    • reproducibility

    • personal air sampling

  • Changing the “No TLV for Mold” Paradigm

    • personal air sampling occupational exposures

    • epidemiology and linkage to health outcomes

    • movement away from I/O comparisons

  • Better Defined Standard of Practice

    • separating the IH from the overnight mold expert

  • Thank you www forensica com

    Thank You!

  • Login