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Replacing CFCs with other chemicals may have resulted in contaminated food



Replacing ozone depleting chemicals with more environmentally friendly alternatives has inadvertently led to harmful compounds contaminating our food and water, according to a study

  • Chlorofluorocarbons were restricted in the 1980s due to their effects on ozone
  • Researchers say the connections used as an alternative could be just as bad
  • In contrast to CFCs, the new compounds do not decompose in the atmosphere, but build up slowly in the Arctic and can reach the food and water supply

By reducing the use of ozone-depleting chemicals in favor of more environmentally friendly alternatives, other harmful chemicals could thrive and contaminate our food.

York University researchers investigated the long-term effects of the 1987 Montreal Protocol to limit the use of chlorofluorocarbons (CFCs).

Many companies are replacing CFCs with substances known as short chain perfluoroalkyl carboxylic acids (scPFCAs) that are not degraded in the environment.

The researchers say that scPFCAs have grown in importance since the 1990s, but since they don’t collapse, they have instead accumulated in the Arctic.

Lead author Professor Cora Young says that because of the potential risk, it is important to examine CFC replacement compounds more carefully before making more.

York University researchers investigated the long-term effects of the 1987 Montreal Protocol to limit the use of chlorofluorocarbons (CFCs).

York University researchers investigated the long-term effects of the 1987 Montreal Protocol to limit the use of chlorofluorocarbons (CFCs).

The step to reduce the use of CFCs came from an international environmental agreement regulating the use of chemicals to deplete the ozone layer. However, the new authors of the study stated that the longer-term consequences were not taken into account.

ScPFCAs belong to a group of synthetic chemicals called perfluoroalkyl substances (PFAS), also known as “forever chemicals” because they are difficult to destroy.

ScPFCAs are used in automotive, electrical and electronics applications as well as in the industrial processing and construction industries.

Professor Young said: ‘Our results suggest that global regulation and replacement of other environmentally harmful chemicals have contributed to the increase in these compounds in the Arctic.

In addition, the results “illustrate that regulations can have important unexpected consequences”.

Young said that by properly examining the replacement connections before others are made, we can identify problems before they “can adversely affect human health and the environment.”

They can travel long distances in the atmosphere and often end up in lakes, rivers and wetlands, leading to irreversible contamination and impairing the health of freshwater invertebrates, including insects, crustaceans and worms.

Current drinking water treatment technology cannot remove them and it has already been found to accumulate in human blood, fruit, vegetables and other plants that we consume.

Ozone depletion is the gradual thinning of the earth’s ozone layer in the upper atmosphere, which is caused by the release of chemical compounds from industry.

“Our measurements provide the first long-term record of these chemicals, all of which have increased dramatically in the past few decades,” said Young.

“Our work has also shown how these industrial sources contribute to the level of ice caps.”

CFCs were removed from an international environmental agreement regulating the use of chemicals that deplete the ozone layer. However, the authors of the new study stated that the longer-term consequences were not taken into account

CFCs were removed from an international environmental agreement regulating the use of chemicals that deplete the ozone layer. However, the authors of the new study stated that the longer-term consequences were not taken into account

Possible health effects of PFAS compounds are cancer, liver damage, thyroid disease, reduced fertility, high cholesterol and hormone suppression.

European countries have recently announced plans to phase out PFAS chemicals by 2030.

The researchers measured three known scPFCA compounds using ice cores that were collected in two arctic locations.

Young said these ice cores act as “time capsules” and track the deposition of pollutants over several decades.

The researchers measured all three known scPFCA compounds at two locations in the high Arctic over several decades and found that they all increased steadily in the Arctic, especially trifluoroacetic acid.

While recognizing the positive effects of the international agreement on the ozone layer, the researchers say that even the best regulations can inadvertently have negative effects.

“In the case of the Montreal Protocol, we saw protection of the stratospheric ozone layer and climate – both extremely important,” said Young.

“But what we’re getting now is this deposit of these persistent chemicals and it seems to be happening globally.”

The results were published in the journal Geophysical Research Letters.

The ozone layer is located in the stratosphere 25 miles above the earth’s surface and acts as a natural sunscreen

Ozone is a molecule of three oxygen atoms that occurs naturally in small quantities.

In the stratosphere, about seven to 25 miles above the earth’s surface, the ozone layer acts like a sunscreen and protects the planet from potentially harmful ultraviolet radiation, which can cause skin cancer and cataracts, suppress the immune system and can also damage plants.

It is produced in tropical latitudes and distributed around the world.

Closer to the ground, ozone can also be created by photochemical reactions between the sun and pollution from vehicle emissions and other sources and form harmful smog.

Although the above-average warm stratospheric weather conditions have reduced ozone depletion in the past two years, the current ozone hole area is still large compared to the 1980s when the depletion of the ozone layer over the Antarctic was first detected.

In the stratosphere, about seven to 25 miles above the earth's surface, the ozone layer acts like a sunscreen and protects the planet from potentially harmful ultraviolet radiation

In the stratosphere, about seven to 25 miles above the earth’s surface, the ozone layer acts like a sunscreen and protects the planet from potentially harmful ultraviolet radiation

This is because the content of ozone depleting substances such as chlorine and bromine remains high enough to cause significant ozone loss.

In the 1970s, it was recognized that chemicals called CFCs, used in refrigeration and aerosols, for example, destroy ozone in the stratosphere.

In 1987, the Montreal Protocol was agreed, which led to the exit from CFCs and recently the first signs of a recovery of the ozone layer in the Antarctic.

The upper stratosphere in the lower latitudes also shows clear signs of recovery, which shows that the Montreal Protocol is working well.

However, the new study, published in Atmospheric Chemistry and Physics, found that it is unlikely to recover in latitudes between 60 ° N and 60 ° S (London is 51 ° N).

The cause is not certain, but the researchers believe that climate change may change the pattern of atmospheric circulation and result in more ozone being removed from the tropics.

They say that another possibility is that very short-lived substances (VSLS) containing chlorine and bromine could destroy ozone in the lower stratosphere.

VSLS include chemicals that are used as solvents, paint strippers and degreasing agents.

One is even used to make an ozone-friendly CFC replacement.

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