Monday, July 9, 2018

Cream cheese mold

Moldy cream cheese- N. Carlson
I lost the lid for my cream cheese container and put it inside cleaned sealed Cool Whip container.  I had forgotten it in the fridge for several weeks. I took it our to spread it on some crackers and ended up tossing it when I saw the mold growth. Before tossing it I tease taped the mold with clear Scotch Tape and examined it under the microscope at 400x power.

Growth of Cladosporium spp. at 400x - N. Carlson

Monday, July 2, 2018

Minnesota Public School Indoor air quality Training Fall 2018

Infrared photo of cold air door leak

School Indoor Air Quality Training

Public schools must have health and safety programs that comply with health, safety, and environmental regulations and best practices, including indoor air quality (IAQ) management. One best practice is that public schools have an IAQ Coordinator. This training will discuss the state’s best practices for school IAQ management. While there is no refresher training requirement, previous attendees are encouraged to attend (content changes every year). Non-public schools, service providers and other stakeholders are also encouraged to attend.

St. Cloud: September 20, 2018           10:00 am – 2:00 pm                   
Duluth: September 21, 2018               10:00 am – 2:00 pm                   
Marshall: October 2, 2018                  10:00 am – 2:00 pm
Roseville: October 10, 2018                  8:30 am – 12:00 pm                         
Webinar: October 30, 2018                  1:00 pm – 4:00 pm

Tuesday, June 19, 2018

Agricultural production under solar panels

Solar farm New Hampshire Gazette

One of the trade offs with solar energy production is the large land area needed for solar production. Farmers are beginning to experiment with various designs to combine solar production with agricultural land use.  In New Hampshire as reported in the New Hampshire Gazette a configuration with the panels 9 feet in the air and five feet apart results in yield reductions of 5 to 10% when compared to the unobstructed areas in front of the panels. The area below can also be used for livestock grazing land. The poles are anchored 8 feet below the surface.

Photo courtesy of Prairie Restoration Inc.

In Ramsey, Minnesota, as reported in Ensia, combining bee hives with a solar panel installation by Connexusenergy also works. The bees provide pollination to the nearby fields and produce honey. In Ramsey Minnesota Bolton Bees combine solar panels with honey production. They have even gone into the craft beer business producing Solarama Crush.

Sustainenergy - Japan

In Japan, Farmers are using the shade from the solar panels to produce cloud ear mushrooms that would have formerly been imported from China.  Combining mycology and solar energy exemplifies sustainable mycology.

Friday, June 15, 2018

Surprise in a walk in cooler

Mushroom in wall - N. Carlson
In October of 2017 an employee noted an unexpected location for a mushroom. This mushroom growth was noted in a walk in cooler. A leak in the pipe provided the water that supported the growth in the wall outside the cooler.

Wide shot of mushroom in wall - N. Carlson
The leak was fixed after the wall outside the cooler was opened up.

Typical fungal growth on a box in a walk-in cooler - N. Carlson

One of the most common fungal organisms found in walk-in coolers is Cladosporium sphaerospermum. Presumptively identified by small diameter colonies growing on dusty surfaces in the cooler including, cardboard, plastic and stainless steel.  Tease tape identification with a microscope can confirm the type of growth.

Cladosporium sphaerospermum - N. Carlson

Friday, June 1, 2018

Fungal growth on sheetrock wall time lapse

The short video below represents the progressive mold growth on Sheetrock in a enclosed container with standing water.  This condition very roughly simulates the interior of a dry wall cavity. To get the full effect turn up the volume on your speakers.

Sheetrock mold growth time lapse 35 seconds

Saturday, March 17, 2018

Not so smooth strawberry smoothie

Several day old strawberry smoothie - N. Carlson
Beware of the several day old strawberry smoothie. This one was was a fuzzy gray when it arrived at the kitchen sink.  I took a tease tape, transferred to a slide with some mounting fluid and examined it under a microscope. The organism has characteristics of both Rhizomucor spp. and Rhizopus spp.  With Rhizopus spp. the sporangiophores start at the same location as the rhizoids (root like structure) individual Rhizopus spp. are connected with a non septate stolon perpendicular to the rhizoids. This is similar to the runners that strawberry plants employ.  With Rhizomucor spp. the sporangiophores branch some distance away from the rhizoids. The branching on this sample is some distance from the rhizoids.

The Rhizomucor spp. sporangiospores are usually under 6 microns in diameter with round to slightly oval spores although some are irregularly shaped.  The sporangiospores in this sample are greater than 6 microns and have the characteristic walnut shell shape of a Rhizopus spp. spore. Both of these organisms can cause strawberries to rot.

Rhizopus spp. line drawing - N. Carlson

Rhizopus spp. or Rhizomucor spp.  - 400x - N. Carlson

The branching at the end is more typical of Rhizomucor spp. - 100x

Close-up of sporangiospores  that are more typical of Rhizopus spp. 

Clinical signs for zygomycete exposure (Mucor spp., Rhizopus spp., or Rhizomucor spp.) infection - 4 min.

Friday, March 9, 2018

Tickborne diseases in Minnesota

MDH  tickborne disease stats from 2007 to 2017

The official start of spring in the northern hemisphere is approaching. With the warmer weather families plan outdoor adventures. This past year I gave a talk on tick borne diseases in Minnesota and the surrounding areas. After reviewing the information, it reinforced my conviction to be careful.

Most of the emphasis has been on Lyme disease transmitted by small black legged ticks. There are other diseases. Fortunately, one of the really nasty tick borne diseases  Powassan Virus (CDC) is rare. Unfortunately the effects of this rare illness are really nasty. It can cause swelling of the brain, crushing headaches, and death.  Doctors can only offer palliative care as there is no effective treatment.

There has been controversy surrounding the treatment for chronic Lyme disease.  A reference below lists some of the side effects from these treatments. As a tick may carry more than one disease this may in part explain ongoing symptoms. Continuing to use the antibiotics for Lyme disease would be ineffectual and make the patient susceptible to more side effects.

On a personal note: I was misdiagnosed with Lyme disease in the 1980s when the blood tests were not as accurate.  I ended up going through the course of antibiotics and met my share of marginally competent phlebotomists.  The experience was not pleasant and it was also ineffectual.

Please review the interesting article below on how the decline in the fox population is associated with an increase in Lyme disease.  Other habitat changes that allow deer mice populations to explode also increase the risk for tick disease transmission.

These are a few of the many tips from MDH tick prevention:
  • Apply DEET on skin and use Permethrin on clothing (not skin). 
  • Walk in the center of a trail
  • Tuck light colored pants inside socks.
  • Inspect and remove ticks within 24 hours. 
  • Avoid walking in woody or brushy areas during times of the year where the risk of tick borne disease is high.

Applying DEET and Permethrin MDH - Approximately 3 minutes.

Tick removal - MDH Approximately 1 minute. 

Tickborne disease references:

University of Manitoba - tick removal - 2 min. 

Tuesday, January 30, 2018

Recipe for DG-18 Agar

Fungal growth on DG-18 Agar

The primary organisms on these two DG-18 agar plates include Penicillium spp., Cladosporium spp., Aspergillus spp., and Wallemia spp. 

Our lab uses DG-18 or Dichloran Glycrol agar to grow culturable xerophilic (dry loving) fungi on indoor air and surface samples. This DG-18 agar grows mould or yeast at water activity (aw) less than .85).  The restricted colony growth and the inhibition of the zygomycete fungi on the plate allow for easier identification and counting of mould colonies on the plate. Some water loving moulds like Stachybotrys spp. and Aspergillus fumigatus do not grow well on this media. We often pair plates of MEA (Malt Extract Agar) with the DG-18 agar to capture organisms needing higher water activity.

DG-18 Media Recipe:
  • 172 milliliters (ml) of glycerine
  • 31.5 grams (g) of DG-18 dry powder agar
  • 1000 ml of distilled water
  • 0.1 g of chloramphenicol in 5 ml of 70% ethanol suspension (add after other ingredients are mixed) - This antibiotic limits bacterial growth on the culture plate.  Autoclave the culture plates after identification to limit problems with the development of antibiotic resistance. 
  1. Heat mixture to boiling using stir bar and a hot plate in a covered 2 liter flask. Make sure all media dissolves into solution.  Observe and modify the stir plate temperature to prevent it from boiling over. 
  2. Use insulated gloves to transfer liquid agar solution to an autoclave.
  3. Autoclave  for a 60 minute cycle at 121 C. 
  4. Remove and keep warm in a 60 C incubator. 
  5. Pour out 13.5 ml of agar onto a Rodac plate or 25 ml onto a 100 petri dish on a laminar flow clean bench.  Refrigerate covered in a plastic bag and store for up to 3 months. 

Friday, January 26, 2018

Acrodontium spp.

Acrodontiium spp. on DG-18
The organism, Acrodontium spp. was found to be a laboratory contaminant on culture plates.  The organism is similar to several other organisms.  The colony growth is slow on DG-18 agar with white fluffy restricted growth at 5 days.

Acrodontium spp. 400x (25 microns between 6 and 7)

The lower end of the conidiophore is wider at the base then the conidia producing structure at the tip of the conidiophore.  I identified the organism using the key in the book, The Genera of Hyphomycetes  These spores would not be identifiable to genera on an Air-o-cell cassette sample.

Saturday, December 30, 2017

Illustrated Genera of Imperfect Fungi by Horace Leslie Barnett

As a student, I used an earlier edition of this book for identifying fungi in my mycology class at the University of Minnesota.  The addition of photos in the front of the book are a welcome improvement over the original text.  Multiple similar organisms are pictured on the same page and this helps to differentiate between them for identification.

Link to book: Illustrated Genera of Imperfect Fungi 4th (fourth) Edition by Barnett, Horace Leslie, Hunter, Barry B. published by Amer Phytopathological Society (1998)

The book is useful for both the beginning mycologist focusing on indoor air and the plant pathologist.  The line drawings aide in identification.  The addition of a 10 micron scale to each of the drawings would also make it even more useful. 

This book provides an excellent companion to Identifying Filamentous Fungi and The Genera of Hyphomycetes. 

Hyaline monomorphic fungi Glen Roberts PhD part 4 - 20 min.

Hyaline monomorphic fungi Glen Roberts PhD part 5 - 29 min.

Hyaline monomorphic fungi Glen Roberts PhD part 6 - 13 min.