university of toronto

The use of paper-based food packaging in the fast-food industry has long been considered a more environmentally-friendly alternative to single-use plastics. However, a recent study led by Miriam L. Diamond, a professor at the University of Toronto’s department of Earth sciences and School of the Environment, revealed that these paper-based containers may not be as safe as previously thought.

Diamond, along with her team, examined 42 paper-based wrappers and bowls, trying to find potentially toxic human-made perfluoroalkyl and poly-fluoroalkyl substances (PFAS).

The team found samples of toxic 6:2 FTOH, or 6:2 fluorotelomer alcohol in abundance. “Another finding: fibre-based moulded bowls that are marketed as “compostable” had PFAS levels three to 10 times higher than paper doughnut and pastry bags,” reads U of T’s report.

“As Canada restricts single-use plastics in food-service ware, our research shows that what we like to think of as the better alternatives are not so safe and green after all,” Diamond says. “In fact, they may harm our health and the environment by providing a direct route to PFAS exposure — first by contaminating the food we eat, and after they’re thrown away, polluting our air and drinking water.”

The use of PFAS in food packaging is a “regrettable substitution of trading one harmful option – single-use plastics – for another.” Diamond added that PFAS eventually end up in our bodies and the environment, where they stay. PFAS have been linked to adverse health effects, including increased cancer risk, thyroid disease, cholesterol levels and decreased immune response and fertility.

Diamond has been studying PFAS exposure and management for several years, and her research has already helped shape policy, such as California’s ban on PFAS in fabrics and cosmetics by 2025.

Check out the full report on PFAs in paper takeout containers here.

Image credit: University of Toronto, Shutterstock

Source: University of Toronto

A new University of Toronto research suggests that people with dark skin colours might have been getting wrong heart rate readings from their wearables all along.

According to the UofT study, the light you see on the rear of wearables is the culprit. Traditional wearables measure your heart rate by beaming light through your wrist and observing how much of it is absorbed. A high rate of absorption signals high blood flow, and vice versa.

The reasoning behind this procedure not functioning optimally for people with darker skins is because of the presence of melanin in higher quantities.

Melanin is a naturally occurring chemical in the body, and it is responsible for determining your skin and hair colour. Coincidentally, Melanin is also a very effective absorbent of light, and that’s how it messes up the wearable’s heart readings.

“People need to be aware that there are some limitations for people with darker skin tones when using these devices, and the results should be taken with a grain of salt,” said Dr. Daniel Koerber, the research co-lead author, in a statement. “Algorithms are often developed in homogeneous white populations, which may lead to results that are not as generalizable as we would like. Ongoing research and development of these devices should emphasize the inclusion of populations of all skin tones so that the developed algorithms can best accommodate for variations in innate skin light absorption.”

This data comes from over 622 other published studies and four of which found that heart rate readings were “significantly less accurate” in dark skin individuals when compared to their light skin counterparts.

According to Koerber, algorithms for tracking heart rate in wearables are generally “developed in homogeneous white populations,” which also contributes to the inaccuracies when said wearables are used by those with dark skin.

The findings of the study will be presented at the American College of Cardiology’s Annual Scientific Session in April. Learn more about the study here.

Via: CTV News