Breaking Down Plastic, One Worm at a Time

A 2022 study by Sanluis-Verdes et al. has found that wax worm saliva is able to break down plastic in just a few hours.

The researchers collected saliva from Galleria mellonella worms and applied it to polyethylene (PE) films. After a few hours, the films had visibly deteriorated and analysis of the films determined that the plastic had oxidized and released additives, evidence that it had degraded.

Credit: Catherine Sheila

Generally, plastics require decades or even centuries to completely degrade through natural exposure to the environment. Because of humanity’s high consumption of plastic, simply dumping them in landfills or waterways only leads to an accumulation that smothers habitats and leaks toxic substances into the soil and water.

This makes finding a safe and quick way of breaking down plastic crucial for sustainable waste management.

Scientists in recent years have been particularly interested in biodegradation, in which naturally-produced enzymes from bacteria, fungi, or animals are used to decompose plastic.

However, scientists have only identified a handful of enzymes that are capable of this, and these enzymes still require years to degrade plastic. They are unable to accomplish the first step of degradation – oxidizing the polymer – and still rely on exposure to UV light and other environmental factors to do it, which usually takes years.

Currently known process of plastic degradation. Credit: Rebecca Yang

Sanluis-Verdes et al.’s experiment demonstrated that the enzymes in wax worm saliva are in fact able to accomplish this crucial step under normal physiological conditions – room temperature, neutral pH, typical background levels of UV – in just a few hours rather than years. The researchers identified an increased presence of ketones in the PE after only applying the saliva a few times, proof that it had been oxidized by the enzymes alone. 

The researchers also tried to identify the enzymes responsible. They were able to pick out two enzymes in the saliva that had a significant effect on PE degradation. Until now, it was believed that bacteria in the gut of wax worms were primarily responsible for plastic degradation, but this discovery indicated that it was the wax worms themselves that oxidized and broke down PE enough for it to then be completely decomposed by bacteria. The researchers also noted that the two enzymes were functionally different from known bacterial enzymes. This suggests that there may be other methods of biodegradation than what is currently known for bacteria.

The exact mechanism will require further studies to determine. If this can be identified and if the enzymes involved can be easily extracted or mass produced, using the enzymes found in wax worms may become a feasible way to naturally and quickly manage plastic waste.

The Impact of Different Types of Stress on Mental Health: A Guide

Stress is an inevitable part of life, but not all stress is created equal. Different types of stress, such as acute stress, chronic stress, work-related stress, and relationship stress, can have significant effects on our mental health. Chronic stress and work-related stress are the most significant predictors of depression and anxiety symptoms. By understanding the effects of different types of stress on mental health, individuals and organizations can take steps to manage and reduce stress and improve mental well-being.

Acute stress is a short-term response to a specific event or situation. It is helpful in small amounts, but prolonged exposure can lead to anxiety and depression. On the other hand, chronic stress persists for a long time and is the most harmful type of stress. Chronic stress can arise from unpleasant experiences during childhood or traumatic events that occur later in life. It can result in mental health issues such as depression, anxiety, and post-traumatic stress disorder (PTSD).

Work-related stress is caused by work-related factors like long hours and difficult coworkers. This type of stress can cause burnout, depression, and anxiety. Relationship stress, on the other hand, is caused by problems in personal relationships. It can also lead to depression, anxiety, and PTSD.

To better understand the impact of different types of stress on mental health, a bar chart is estimated based on a data set available survey of 500 individuals. The chart shows the percentage of individuals experiencing depression and anxiety symptoms for each type of stress. This helps to illustrate the effects of stress on mental health and can provide insight into ways to manage and reduce stress.

Table 1: Number of Individuals Affected by Different Types of Stress

 

Figure 1: The bar chart shows the percentage of individuals experiencing depression and anxiety symptoms for each type of stress. Chronic stress has the highest incidence of depression and anxiety symptoms, with 70% of individuals experiencing at least one symptom. Work-related stress also has a high incidence of depression and anxiety symptoms, with 55% of individuals experiencing at least one symptom. Acute stress and relationship stress have lower incidence rates, with 30% and 25% of individuals experiencing at least one symptom, respectively.

Chronic stress has the highest incidence of depression and anxiety symptoms with 70% of individuals experiencing at least one symptom, followed by work-related stress with 55%. Acute stress and relationship stress have lower incidence rates of 30% and 25%, respectively.

Overall, the data suggests that chronic stress and work-related stress are the most significant predictors of depression and anxiety symptoms. Being aware of the effects of different types of stress on mental health can enable us to take measures to manage stress and preserve our mental well-being.

Why does everyone I know vape? Nicotine is why.

 Thousands of Canadians are becoming addicted to nicotine. There has recently been an increase in the popularity of nicotine products such as vapes, cigarettes, and nicotine pouches among young Canadians. 

Figure 1. Vape pen and Cigarette Source:Wikimedia

Many teens turn to vaping or nicotine pouches believing they are safer to consume than tobacco products but the truth is that they are all harmful. The nicotine in these tobacco-free products is extracted from tobacco giving it its addictive quality. Nicotine is an extremely addictive, fast-acting psychoactive chemical. It stimulates the release of adrenaline and dopamine. While nicotine is not generally the root cause of illness or death, its presence in all smoking products is what gets people addicted. The general public is becoming addicted to nicotine products at an alarming rate.

 

Figure 2. Chemical structure of Nicotine Source: Wikimedia

The rise in nicotine addiction in adolescents can be linked to the rise of vape usage. The Canadian Tobacco and Nicotine survey of 2021 concluded that almost half of all adults aged 20-24 reported using vape products at least once. Similarly, they found that 29% of youth aged 15 to 19 years of age had tried vape products. 

Figure 3. Vaping statistics among youth in Canada

 Nicotine has been proven to be especially harmful to developing adults. Since the brain has not fully developed until at least 25 years of age, any nicotine usage in adolescence can cause irreversible damage to it. In adolescents, nicotine particularly affects the prefrontal cortex which is the area of the brain that is responsible for executive functions and attention performance.  Nicotine has both short and long-term effects on the brain such as developing mood disorders and permanently lowering impulse control. 

This is a problem that must be addressed. Keeping Canadians away from nicotine is vital to their well-being.

-Oscar Caridad

Blue Light – A Propagated Myth!

https://unsplash.com/photos/N7Bjz9vY67E

Unsplash Photo by Lukas Blaskevicius (Editorial, Technology) Unsplash

Device users are not a risk of eye damage due to blue light emitted from their devices, but they may be at risk of poorer sleep.

In 2019, Director Dr. David Ramsey of Ophthalmic Research at Lahey Massachusets Hospital and his study maintained that “many retail stores have ambient illumination twice as great…as [ones] iPhone, [and that] the sun yields illumination ten times greater!”

Light sources such as incandescence (light bulbs) and LEDs emit a broad spectrum of light, namely 400 to 700 nanometers (nm). Blue light is in the 400 to 450 nm range, carrying more energy than red light, raising concern. 

Our retinas regularly absorb blue light emitted by the sun. For roughly 300,000 years, humans have sustained minor to no retinal damage: if it were damaging, we would have evolved optically blind.

Device intensities are much less than the sun and are regulated by manufacturers using light filters. 

In 2019, CBC News conducted a Marketplace undercover investigation to debunk the concerns. In addition, Dr. SUNIR J. GARG, American Board Ophthalmologist and clinical researcher, addressed the myth.

“Why you don’t need blue light lenses: Hidden camera investigation (Marketplace)” A 2019 CBC Interview with Dr. SUNIR J. GARG, American Board Ophthalmologist, about why blue light glasses are unnecessary. Youtube

However, in the Harvard study, Dr. Ramsey adds that using devices late at night mimics sunlight, restraining melatonin production, a sleep-inducing hormone. This stimulates your circadian clock (your body’s 24-hour sleep clock), tending to delay your sleep cycles, disrupting your sleep, and increasing drowsiness the following morning. 

By stopping use of electronic devices 30 minutes before bed, you can increase REM (deep-stage sleep), reduce morning drowsiness, and maintain a consistent circadian rhythm, which in itself has its own benefits. 

In short, research before propagating a supposed “scientific claim” and reduce your screen time before bed.

~ Octavian Turner

The Gore-Tex Enigma

Gore-Tex is a highly versatile material that has garnered a lot of publicity in recent years.

It is a magical material in many respects. Water simply glides off it, leaving it bone dry. Being also very breathable and light, it is no surprise that it is the ideal material for water resistant clothing.

First invented in 1968 by Wilbert and Robert Gore, it is made of polytetrafluoroethylene, more commonly known as Teflon. Not the hard stuff though. It’s basically Teflon that has been stretched… a lot.

With the likes of Adidas and Nike incorporating it into their outdoor wear products, its worldwide use and popularity has called into question the manufacturing process and its environmental impacts.

Teflon is a very durable material that does not degrade easy and lasts for a long, long time. This is a good thing right? Well, yes… But what happens when that fifteen year old jacket you own is discarded or lost, and finds itself buried in the dirt outside an abandoned parking lot?

It persists. And doesn’t degrade. For centuries.

 

PFC’s or perfluorinated compounds are those that contain only carbon and fluorine atoms. Teflon is made from these compounds.

Chemical structure of Teflon: repeating units of carbon and fluorine atoms

The problem with PFC’s is that they tend to accumulate within our bodies and the environment. They are difficult to break down as they are quite unreactive.

A class action lawsuit at a DuPont Teflon plant found a very strong association between working with PFC’s and two types of cancer. Since then, many other studies have found a correlation between exposure to certain PFC’s and negative health outcomes.

To be clear, it isn’t the wearing of Gore-Tex products that is concerning. Also, not all PFC’s are harmful. However, the manufacturing process dispels many harmful PFC’s into the environment.

Gore-Tex jackets are also near impossible to recycle. They are made in complex ways, and the design process involves multiple layers, glues, and components.

Gore-Tex must not be completely written off though. Gore and company have assured investors and the public that they are stopping the use of many harmful PFC’s in their manufacturing process. However, the effects of this are yet to be seen.

There are also other, more intriguing applications of this remarkable material.

What is not talked about nearly enough is the role of Gore-Tex in medicine. It has shown to be ideal for use inside our bodies.

Being so unreactive, it allows the body’s cells and tissues to grow through it without any side effects. This makes it a viable material for many medical applications.

Like most technologies, Gore-Tex is complicated in many ways. Its strengths in one regard prove to be its downfall in another. It seems the jury is still out on this one

– Salik Rushdy

Non-Hormonal Birth Control Pills for Males May Be Within Reach

Recently, scientists at the University of Minnesota found two promising compounds that may become the first non-hormonal contraceptive drugs for males. Testing on mice found that these compounds reduce sperm count effectively and present no side effects.

There are currently no non-hormonal birth control pills on the market for females or males, despite these pills likely having fewer harmful side effects than the hormonal birth control methods available for females.

And since males continuously generate sperm while females are born with all potentially fertile eggs, it is easier for scientists to find approaches that reversibly stops sperm production in males rather than risk “spoiling” the non-renewable pool of eggs in females.

Picture depicting the meeting of sperm and egg, which leads to fertilization and pregnancy. Image Credit: https://flic.kr/p/MCcsUf

The first potential drug discovered is a chemical named YCT529, reported by Dr. Gunda Georg’s group in spring 2022. This molecule was designed to inhibit the function of the protein retinoic acid receptor alpha (RAR-α). Georg’s scientists found that a lack of RAR-α protein in male mice leads to sterilization, but no additional side effects. When YCT529 was orally administered to the mice for 4 weeks, their sperm count reduced drastically, and the drug was 99% effective in preventing pregnancy.

Chemical structure of non-hormonal male contraceptive YCT529. Image Credit: Ying Cai

The same group of scientists reported the second drug named EF-4-177 in early 2023. The target of this molecule is an enzyme named cyclin-dependent kinase 2 (CDK2) which helps in sperm cell production. The scientists reported an over 45% decrease in sperm count of the mice after 28 days of treatment with EF-4-177.

Currently, a startup named YourChoice Therapeutics based in Berkeley, California is working to market YCT529 to humans soon. According to their website, the company has tested on dogs and primates with positive results. Their graphics show that after two weeks of treatment with YCT529, sperm levels in dogs drop to zero and primates do not produce enough sperm to be fertile.

If a side effect-free non-hormonal birth control pill for males is introduced to the public, it would expand contraceptive options for those with testicles beyond condoms and vasectomy. As well, it would make it easier for the responsibility of pregnancy prevention to be shared between partners in a relationship.

Hopefully, more research to come will soon make non-hormonal birth control pills for males a reality.

~ Ying Cai

Are mRNA Therapeutics the Future of Medicine?

Current mRNA researchers around the world are set on treating cancer, diabetes, cystic fibrosis, HIV, and many other diseases. Will mRNA therapeutics amount to more than their viral protection against Covid-19?

Messenger RNA or mRNA strand 3D rendering illustration with copy space. Genetics, science, medical research, genome replication concepts.

Digital representation of mRNA structure. Source

 

The covid-19 pandemic led to the first mass production of mRNA vaccines. Scientists worked collaboratively and tirelessly to quickly produce this vaccine under the urgency of a global pandemic.

The global success of this vaccine brought great attention to other developing mRNA therapeutics. These therapeutics are being studied to treat cancer, sickle cell anemia, cystic fibrosis, heart failure, and even food allergies.

So, when will these therapies be ready?

Unfortunately, there are still some kinks to work out.

Currently small molecules make up 90% of pharmaceutical drugs. These organic compounds have dominated the medical world as they can diffuse into cells and bind precisely to cellular targets responsible for disease.

People with cystic fibrosis (CF) currently rely on small molecule drugs. The drug Trikafta was approved for use by health Canada in 2022 and by 2030 is projected to decrease the number of CF-related deaths by 15%.

CF is caused by the loss of function in the CFTR protein. Trikafta helps return the CFTR to somewhat normal function.

mRNA therapy for CF would work differently. mRNA could provide the genetic information to produce the fully functional protein.

Those with CF would still carry DNA which codes for the dysfunctional CFTR protein. But, in the cell cytoplasm delivered mRNA could produce the functional protein and reverse the disease.

As great as that sounds, it will be sometime for mRNA therapeutics to overtake the use of organic drugs for CF. As of now most clinical trials are still struggling to see mRNA live up to it’s full potential.

The main issue with mRNA therapeutics is targeting the diseased cells. mRNA is delivered in lipid nanoparticles (LNPS).

mRNA at cell surface in a LNP. source

 

Altering these LNPs to be specifically taken up by diseased cells has proved to be a great challenge to be overcome by mRNA scientists.

For now, small molecule drugs hold their place as the number one drug type.

Globally researchers are working tirelessly to prove that the promised revolutionary therapeutics are not just a pipe dream.

Medicine is a dynamic field and new therapeutics like mRNA are worth looking out for!

Exposing the dark side of the skin-lightening industry

Minnesota Department of Health warns consumers to steer clear from skin-lightening products (SLPs). Their recent investigation on SLPs revealed dangerously high concentrations of unlisted ingredients that can harm users’ health.

 

Skin lightening refers to the practice of lightening complexion by reducing the skin’s natural pigment, melanin. Dermatologists prescribe patients products with low concentrations of active ingredients to treat certain pigmentary conditions and post-inflammatory hyperpigmentation. However, due to potential adverse complications, many countries either banned or strictly regulate these ingredients. 

 

Skin colour has long been the social-economic benchmark in many countries, predominantly in Asia-Pacific, where individuals often affiliate lighter complexions with attractiveness and more career opportunities. A survey of 667 participants revealed that appearing lighter was the most common reported reason for using SLPs, followed by to appear more attractive, regular skincare products, social influences, and others (Table 1).  

Figure 1: Summary of users’ reasons for using SLPs from 667 participants.

These growing demands created the lucrative business of SLPs, which was valued at US$8.8 billion in 2020. 

 

Unsurprisingly, most toxic SLPs remain accessible in local markets and promote on social media. Some go undercover by omitting harmful ingredients or using counterfeit labels. 

Hydroquinone, a potent SL agent for hyperpigmentation treatments, causes permanent blue-black facial discoloration (Figure 1) or skin thinning with high-dosage applications, said Dr. Desai, a board-certified dermatologist at the University of Texas Southwestern Medical Center.

Figure 2: Discolouration from long-term usage of hydroquinone-containing products. Source: Wikimedia

 

UK-based optometrists recently diagnosed three patients with corneal degeneration. This condition leads to a loss of vision over time, most likely from using hydroquinone-containing products for years, as the patients reported.

Corticosteroid, a widely-used topical steroid for skin inflammation conditions, is also a potent bleaching agent. Steroid-dependent reactions (SDR) are the tell-tale signs of chronic misuse of corticosteroids over an extended period (Figure 2). Rashes, skin sensitivity to sunlight, and infections occur when SDR patients withdraw from topical steroids. 

Figure 3: Steroid-Dependent Reactions. Source: Wikimedia

 

Mercury, another dominating ingredient in unregulated SLPs, inhibits melanin production to reveal a lighter complexion. The well-documented list from Pan American Health Organization on associated risks from mercury poisoning does not look so pretty. 

These risks range from multiple major organ failures – kidney, liver, etc. – to psychological issues – psychosis, depression, anxiety, and early-childhood development issues. 

Moreover, determining factors when assessing a patient’s health on the severity of mercury exposure include the product’s concentration, period of exposure, other compounds changing mercury’s chemical properties, etc. The complex nature of different coexisting factors raises another problem for proper diagnoses, as indicative symptoms of mercury poisoning may not always manifest equally.

While mainly mercury poisoning from SLPs occurs via skin absorption, inhalation of mercury vapours is not off-limit. Simply put, users put not only themselves at risk of mercury poisoning, but also the whole household. 

So how should buyers go on from here?

“Consumers should always check the ingredients of their skin creams, be suspicious of low prices which are likely to indicate the lotion is fake and potentially harmful, and never use a product containing hydroquinone,” said Simon Blackburn, chairman of Local Government Association’s Safer and Stronger Communities.

 

Ashlynn Nguyen

 

 

 

Enzymes – A Solution in the War Against Plastics

It should not be a surprise to people that it can take over 500 years for UV radiation – light from the sun to break down a piece of plastic. But what if there is a faster way to break down single-use plastics?

Researchers at the University of California, Berkeley invented a new way to decompose consumer plastics in a short amount of time, simply with heat, water, and nano-dispersed enzymes.

Plastic waste covering the shoreline. Source

UC Berkeley professor Dr. Ting Xu and her research group  developed a nanoscale enzyme that can eat away at the polymers in plastics. These nanoscale polymer-eating enzymes can be embedded into plastics during manufacturing. The enzymes were wrapped around plastic resin beads. These beads are melted and can be manufactured into single use consumer plastics. To prevent the enzymes from activating when not required, a random heteropolymer (RHP) coating is applied to hold enzymes without restricting the flexibility of tensicity of the plastics.

Xu likened this process to organic composting. By adding water and heat, the RHP polymers is removed and starts eating away the polymers into smaller subunits.

The research conducted by Xu and her group found that the enzymes took about a week to degrade most of the plastics. Polylactic acid (PLA) and polycaprolactone (PCL) based plastics embedded with nanoscale polymer eating enzymes are able to break down the polymer chains into smaller molecules, such as lactic acid.

Plastic cups made from biodegradable plastics. Source

It is clear there is still more research needed in this field. Currently, Xu is developing other modified RHP-wrapped enzymes that can stop the degradation process at specific points in it’s degradation so that the polymers can be recycled into new plastics.

“[Humans] are taking things from the Earth at a faster rate than we return them,” said Xu. “Don’t go back to Earth to mine for these materials, but mine whatever you have, and then convert it to something else.”

As consumers, we can play an important role reducing our consumption on single use plastics and create a more sustainable environment for ourselves and future generations.

 

Raymond Tang

SOY SAUCE IN SKIN CARE: THE RISE OF KOJIC ACID

Soy sauce, sake, and skincare all have one thing in common — Kojic Acid. 

Kojic acid, a by-product of soy sauce and sake production, is currently a debated skincare ingredient due to potential contact dermatitis, an uncomfortable rash, when used on sensitive skin.

Chemists at the University of Pretoria in South Africa are studying the benefits of kojic acid in skincare. Their research has shown recent developments in kojic acid’s effectiveness and safety. 

Due to various beauty influencers on platforms like Tiktok, Instagram, and Youtube celebrating kojic acid as a miracle whitening product, it is important to understand the true abilities and downfalls of this ingredient. 

Hyperpigmentation can be treated through the use of kojic acid (Credit: Büşranur Aydın, Pexels)

This ingredient is highly sought after due to its skin-whitening properties. Particularly, the acid is being used to spot treat facial hyperpigmentation from sun spots and acne scars. 

Kojic acid’s skin whitening features are derived from its ability to inhibit tyrosinase, the enzyme needed to produce the skin pigment melanin. While kojic acid should not be used to lighten overall skin complexion, its “mild antioxidant, antimicrobial, and exfoliating properties,” according to Board-Certified Dermatologist Dr. Jennifer MacGregor, makes it suitable for small-scale skin lightening. 

Chemical structure of Kojic Acid (Credit: Fuzzform, Wikimedia Commons)

Despite its generally mild properties, kojic acid should still be used with caution. Prolonged use may increase sensitivity to sun exposure and dermatitis for those with sensitive skin. Discoveries from the mentioned study suggest against using kojic acid at concentrations that exceed 1%. At this concentration, there is a greater risk for contact dermatitis. 

Popular skincare brands are saturating the market with kojic acid. The compound can be combined with other well-known ingredients, such as vitamin C, glycolic acid, niacinamide, and hydroquinone. 

Depending on the additional ingredients, kojic acid can be diluted to be tolerable for sensitive skin or compounded to accelerate whitening abilities. 

Kojic acid can currently be found in various forms to suit consumer preferences. Currently, the most sought-after forms of kojic acid are SkinCeuticals’ Discoloration Defense serum, Koji White’s Kojic Acid Skin Brightening Soap, and Versed Skin’s Weekend Glow Daily Brightening Facial Toner. 

As more research is done to understand the properties of kojic acid, beauty and skincare communities are likely to see a rise in the acid’s popularity. Consumers must continue to be vigilant to ensure they are using safe concentrations for their skin conditions.

-Carissa Chua