• The CFCs problem
• Recycling
• Ozone Q&A

			The CFCs problem

In 1974, Nobel prize winner Dr. F. Sherwood Rowland and his colleague Dr. Mario Molina proposed a theory that chlorofluorocarbons (CFCs) damage the stratospheric ozone layer. At the time, CFCs were being used in refrigerators, air conditioners, industrial processes and as propellants for some aerosol products. The scientists were worried about the stratospheric ozone layer because it consists of a particularly active form of oxygen that filters out much of the sun’s harmful ultraviolet radiation.

Scientists continue to warn that ozone depletion will allow rising levels of ultraviolet radiation to reach the Earth’s surface, which may lead to a potential increase in skin cancer, cataracts and global warming.

As a result of Rowland and Molina’s discovery, American aerosol manufacturers took the lead in switching from CFC propellants to suitable alternatives. In fact, by 1978 when the U.S. EPA banned the use of CFC propellants, most of them had already voluntarily stopped using CFCs. An exception was made for some asthma inhalers, but they will also be CFC-free by December 31, 2008. This will complete the phase out of all CFC propellants in consumer aerosol products produced and sold in the U.S. Other ozone-depleting substances that were used in some aerosol formulations for non-propellant purposes also have been phased out according to the legislative timetable.

Throughout the 1980s, several countries–including Canada, Mexico, Australia and several European nations–passed regulations banning CFC use in aerosol containers. Under the Montreal Protocol agreement, CFC propellant production was phased out as of January 1, 1996 in industrialized countries and will be phased out by 2010 in developing nations.

The Environmental Protection Agency

			Recycling

Aerosol products ARE recyclable, just like any other empty steel container!

Given the public’s concern about solid waste disposal, the aerosol industry teamed with the steel industry to promote the collection of empty aerosol cans in recycling programs nationwide. Thousands of communities now include aerosol product recycling in both household residential and curbside buy-back and drop-off programs.

Most aerosol cans are made of steel. Post-consumer cans (food, beverage, paint and aerosol products) are in demand because steel furnaces require recycled steel to make new steel. Today’s steel aerosol cans contain an average of 25 percent recycled content.

Aluminum aerosol containers are also recyclable. Check with your local recycling coordinator or aluminum collection site for details in your area.

Many recyclers and community recycling officials are simply not aware that the U.S. EPA recommends that all aerosol containers  (including pesticide containers) be recycled once they are empty.

Disposing of Aerosol Products Properly

Aerosol products, like all other household and personal care product containers, should be disposed of properly. Recycling is the best way to dispose of an empty household aerosol container. But if your community does not yet accept aerosol containers for recycling, the following guidelines may be useful:

• Use up the entire product purchased. Since aerosol containers are airtight and the contents will not spoil or evaporate, they can be used and stored over long periods of time.
• Dispose of the empty container through normal household waste disposal according to label directions, or contact your local solid waste disposal office for instructions for specific products.
• Never dispose of an aerosol container in roadside dumps or open trash fires.

What You Can Do

You can help by encouraging your community to accept empty aerosol cans along with other metal containers. The Steel Recycling Institute can provide more information about recycling (1-800-876-7274) or visit www.recycle-steel.org.

For a list of recycling centers in your area that accept aerosol cans, please visit www.earth911.org.

			Ozone Q&A

Q: Are there Two Kinds of Ozone: Good Ozone and Bad Ozone?

A:  Ozone is always the same O₃ molecule; its location in the atmosphere determines whether it is considered “good” or “bad” ozone.  Ninety percent of ozone is “good” and is found in the stratosphere and it forms the Earth’s protective ozone layer.  The remaining ten percent is “bad” ozone, found in the troposphere close to the ground.

There are environmental concerns for both good and bad ozone, but the problems are unrelated to each other.  Ozone depletion and the seasonal thinning of ozone near Antarctica, relate to good ozone in the upper atmosphere; smog and ozone pollution that cause respiratory irritation, among other problems, involve bad ozone at ground level.

Q: What is the Earth’s Protective Ozone Layer?

A:  Ozone occurs naturally in the stratosphere, protects the Earth and its inhabitants, and is produced and destroyed at a constant rate.  It is gradually being depleted by certain classes of both naturally occurring and man-made chemicals.  The latter are primarily chlorofluorocarbons (CFCs), halons, and other ozone-depleting substances (used in refrigerants, foaming agents, fire extinguishers, and solvents). These ozone-depleting substances degrade slowly and can remain intact for many years as they move through the troposphere until they reach the stratosphere. There they are broken down by the intensity of the Sun's ultraviolet rays and release chlorine and bromine molecules, which destroy "good" ozone. One chlorine or bromine molecule can destroy 100,000 ozone molecules, causing ozone to disappear much faster than nature can replace it.

It can take years for ozone-depleting chemicals to reach the stratosphere, and even though we have reduced or eliminated the use of many CFCs, their impact from years past is just starting to affect the ozone layer. 

In the 1970s, American aerosol product manufacturers voluntarily took the lead in reducing CFC usage by switching to non-CFC propellants.  In 1978, U.S. regulations banned CFC use as aerosol propellants.  An exception was made for some asthma inhalers, but they will also be CFC-free by December 31, 2008. This will complete the phase out of all CFC propellants in consumer aerosol products produced and sold in the U.S. 

Throughout the 1980s, several countries – including Canada, Mexico, Australia and several European nations – passed regulations banning CFC use in aerosol containers.  Under the international Montreal Protocol agreement, CFC propellant production was phased out as of January 1, 1996, in industrialized countries and will be phased out by 2010 in developing nations.

Q:  What is Ground Level Ozone?

A:  Bad ozone is found in the troposphere and is a component of “smog.”  It is totally unrelated to CFC use.  Instead, motor vehicle exhaust and industrial emissions, gasoline vapors, and chemical solvents are some of the major ozone precursors.   Strong sunlight and hot weather cause ground-level ozone to form in harmful concentrations in the air. Many urban areas tend to have high levels of bad ozone, but other areas are also subject to high ozone levels as winds carry motor vehicle exhaust and industrial emissions hundreds of miles away from their original sources.

Repeated exposure to ozone pollution may cause permanent damage to the respiratory system. It can worsen bronchitis, heart disease, emphysema, and asthma. Healthy people also experience difficulty in breathing when exposed to ozone pollution. Because ozone pollution usually forms in hot weather, anyone who spends time outdoors in the summer may be affected.  Ground-level ozone damages plant life as it interferes with the ability of plants to produce and store food, making them more susceptible to disease, insects, other pollutants, and harsh weather.

Q: What is being Done About Bad Ozone?

A:  The Clean Air Act Amendments of 1990 require states and cities to implement programs to further reduce emissions of ozone precursors from sources such as cars, fuels, industrial facilities and power plants.  Power plants will be reducing emissions, cleaner cars and fuels are being developed, many gas stations are using special nozzles at the pumps to recapture gasoline vapors, and vehicle inspection programs are being improved to reduce emissions.

Q: Is There Really a “Hole” in the Ozone Layer?

A:  The ozone “hole” is a well-defined, large-scale destruction of the ozone layer over Antarctica that occurs each Antarctic spring. The word "hole" is a misnomer; the hole is really a significant thinning, or reduction in ozone concentrations, which results in the destruction of up to 70% of the ozone normally found over Antarctica.

The science of ozone thinning is complicated.  Unlike global ozone depletion, the ozone “hole” occurs only over Antarctica.  Since most ozone-depleting substances are released in the northern hemisphere, a common question is why the ozone “hole” occurs over the Antarctic. The first part of the answer is that even though most of these chemicals are heavier than air, regardless of where they're released, they mix throughout the troposphere over about a year, and then mix into the stratosphere in two to five years. The second part of the answer is that although the overall process is similar between global ozone depletion and the ozone “hole”, there are two different types of ozone depletion chemistry.

The first kind is called homogeneous depletion; resulting from reactions as gases mix together, it is responsible for the reduction in global ozone levels. The 5-10% drop in ozone over the US is an example of homogeneous chemistry.

The second kind of ozone depletion chemistry, called heterogeneous, causes the radical destruction of ozone over the Antarctic each spring. It results from reactions on the surfaces of ice particles. The existence of these particles, and the seasonal and geographic location of the “hole,” all result from a combination of meteorological and other effects that are specific to Antarctica at that time of year.

Q: Does Ozone Depletion Cause Global Warming?

A:  The greenhouse effect is a natural phenomenon that helps regulate the temperature of Earth.  The sun heats the Earth, and clouds and greenhouse gases in the atmosphere trap some of this heat. Although water vapor is the most abundant greenhouse gas, fuel burning and other human activities release greenhouse gases, as well.  The most important ones are carbon dioxide, methane and nitrous oxide.

Without any greenhouse gases, the Earth would be uninhabitable.   Human activity has increased the level of greenhouse gases in the atmosphere, which may have contributed to the average warming of 1.1 degrees Fahrenheit over the last century.

Although many people confuse ozone depletion and global warming, they are primarily separate problems.  While stratospheric ozone is a natural greenhouse gas that helps absorb heat, the ozone hole that has been shown to form over the polar region is not the cause of global warming.