The fungus among us

By: Felicia Z. Paredez

Growth of different mycotoxin producing fungi on wallpaper. Figure taken from Aleksic et al. 2017.

 

A humid indoor environment, like your bathroom, can harbor fungi. Some fungi that produce mycotoxin can pose a health risk to any individuals that are exposed. In a study by Aleksic and colleagues, they measured the amount of toxins produced from fungi growing on wallpaper and the aerosolization of these toxins. Mostly these toxic particles were aerosolized from moldy wallpaper and the launching and concentration of the aerosolized particles were dependent on the type of fungal species and the velocity of the launch. It was found that under ideal conditions mycotoxin particles, small enough to be inhaled deeply, could be aerosolized. This study shows that there is a risk that building materials in our work and house environments can become ideal spaces for the harborage of mycotoxin producing fungi. Consequently, it also raises the question of “what is the long term risk of repeated exposure to these particles and is there any way to avoid them?”.

Aleksic B, Draghi M, Ritouz S, Bailly S, Lacroix M, Oswald IP, Bailly JD, Robine E. (2017). Aerosolization of mycotoxins after growth of toxinogenic fungi on wallpaper. Appl Environ Microbiol 83:e01001-17.

The Harms of Soil Sands

By: Leslie Romero

With the successful growth of the Athabasca soil sands industry, there is no doubt concerns have risen. This area contains the largest deposits of bitumen or extremely heavy crude oil estimated to be equivalent to 170 billion barrels of crude oil! These concerns are in regard to the possible contamination of nearby fresh water sources, specifically the Athabasca River. Some of the Athabasca river tributaries flow towards the direction of major oil sand surfaces. Thus, studies have been conducted to analyze for any potential contaminants these fresh water sources may be receiving from adjacent oil sands (Sun et al., 2017). From these studies, it was concluded that Naphthenic acids were found at very high concentration in natural water north of the industry, as well as elevated levels in groundwater. Bitumen-derived organics were also found only on surface water. This study can be taken into consideration of the future environmental impacts soil sand industry could cause if there are no regulations. Consequently, further focus should be directed into monitoring of seepage into tributaries. 

                             Figure 1. The Athabasca soil sands. Figure taken from Sun et al. 2017

Chenxing Sun, William Shotyk, Chad W. Cuss, Mark W. Donner, Jon Fennell, Muhammad Javed, Tommy Noernberg, Mark Poesch, Rick Pelletier, Nilo Sinnatamby, Tariq Siddique, and Jonathan W. Martin.

Characterization of Naphthenic Acids and Other Dissolved Organics in Natural Water from the Athabasca Oil Sands Region, Canada. Environmental Science & Technology 2017 51 (17), 9524-9532

DOI: 10.1021/acs.est.7b02082

Who Said Fashion Wasn't Deadly?

By: Jackeline Santillano

Figure 1. This image shows how the shirts were hanged indoors and exposed to high concentrations of BP-3 and then how those same shirts were used by participants of the study. Figure taken from Glenn et al. 2017.

If you ask someone if they think their shirt is deadly, the most probable answer will be no. No one thinks that a simple shirt could be a danger to your health in any type of way. A study done on the dermal uptake of Benzophenone-3 from clothing was conducted to see how much of a burden this endocrine disruptor would be once it has gotten into your home and onto your clothing via plastics and sunscreens. The study describes how cotton shirts were exposed constantly to BP-3 for 32 days at high concentrations with the final concentration being 4.4 μg/m³. The participants then wore the shirts for three hours and had urine samples collected and analyzed to reveal that the sum of BP-3 excreted were sums of 12, 9.9 and 82 μg for the different participants. This study mainly implies that the applications of cosmetics and other care products are not the only issue but that BP-3 in our indoor air could cause a greater burden to our human health as well.

Glenn C. Morrison, Gabriel Bekö, Charles J. Weschler, Tobias Schripp, Tunga Salthammer, Jonathan Hill, Anna-Maria Andersson, Jørn Toftum, Geo Clausen, and Hanne Frederiksen (2017). 

Dermal Uptake of Benzophenone-3 from Clothing. Environmental Science & Technology

Article ASAP. DOI: 10.1021/acs.est.7b02623

No bacteria in your food? I don't think so...

No bacteria in your food? I don't think so...

Figure 1 Retrieved from: http://blog.infinityhealthwellness.com/2013/07/autistic-children-found-to-have-fewer.html

There exist high standards when talking about hygiene in food industry. But, there is one organism that is able to outsmart the processes to achieve these high standards. Listeria monocytogenes is a foodborne bacterium that can reproduce in meat and cheese. This organism is well known for surviving under high stress conditions (alkaline and oxidative) that other microorganisms cannot. L. monocytogenes performs some genetic mechanisms that blocks the effect of cleaning solutions. This ability is encoded in their genome, and scientist are still working on understanding this genetic ability. They have hypervariable regions in their DNA, which means these regions often change and contains inserts (sections) that enhances L. monocytogenes survival. SSI-1 is the region of the DNA that provides survival against the hygiene standards in food processing. In addition, two other proteins, which code from genes, were observed to increase during stress conditions. One of these regulates activity of second protein, and the other is a protease that breaks down other proteins. Scientists keep investigating about the inhibition of these genes to improve hygiene standards. 

Reference:

         Veterinärmedizinische Universität Wien. (2017, August 30). An island getaway: Why some Listeria strains survive good food hygiene standards. ScienceDaily. Retrieved from www.sciencedaily.com/releases/2017/08/170830095024.htm

What’s really around a beach?

Beaches are family places, where you go to have fun, enjoy the sun and the ocean. It may seem great, but little do people know what’s really in or around them. Some sources that secrete fecal contamination are; partially treated wastewater that happens during periods of capacity of over flowing or combined sewers, disconnected sewer lines, failing septic systems, septic maintenance, etc. There's also non-human sources as well such as; leakage from ponds and storage areas where livestock manure is, land manure, wildlife, etc. It’s important to know because not only do humans swim in the ocean but so do marine life. A study was conducted to get samples for pathogens, in four microbial categories, which were protozoa, pathogenic bacteria, bovine viruses, and human viruses. This study showed that infections and illnesses were happening due to pathogens. Human virus in the present study was greater than previous studies at the Lake Michigan beaches. Pathogenic bacteria in the present study showed a greater amount than the previous Great Lake beaches. One thing to do for the future, is replacing the sewer lines with a rubber where the piping connects so that there’s no leakage, and maybe monitoring them as well. For the non-human sources, maybe by having a filtering system to clean out the water before going into rivers and leading to the oceans. This can be some examples, because fish do travel around the ocean and we eat marine life. These pathogens are not just hurting our environment but our marine life, and in the end, us as well.

 

Fig. 1: Fecal Contamination from human and non-human sources. 

Reference:

Corsi SR, Borchardt MA, Carvin RB, Burch TR, Spencer SK, Lutz MA, McDermott CM, et al. 2016. “Human and Bovine Viruses and Bacteria at Three Great Lakes Beaches: Environmental Variable Associations and Health Risk.” Environmental Science & Technology 50 (2): 987–95.