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Q: What does “microwave safe” mean?  

A: “Microwave safe” is a widely used yet somewhat confusing term.  Does it mean safe for you or safe for the container?  When manufactures label their products as “microwavable” or “microwave safe” what they really mean is that the container will not bubble, melt, or otherwise get ruined when heated in the microwave. 

This provides no guarantee that chemicals will not leach out of the container when it is heated.  Serious health concerns have been raised about harmful leaching of BPA (bisphenol-a), an industrial chemical commonly used in the manufacture of microwave ovenware.  BPA is a known hormone disruptor, which can interfere with the body’s normal endocrine functions.   Scientific studies have linked BPA to cancer and reproductive problems.

When cooking or heating foods in the microwave opt for glass and ceramic containers.  Avoid using plastic containers, yogurt cups, Styrofoam boxes or trays, and plastic wrap in the microwave.

Q: Is bottled water better than tap water?

A: You have probably never stopped to think about it, but not all bottled water is the same.  There are several types to consider, some of which include: spring water, natural mineral water, sparkling water, and purified water. Whatever your preference, you should know that bottled water is generally not regulated as strictly as tap water. Tap water is required to meet more stringent standards at both the federal and local levels. To check on the quality of drinking water in your area click here.

According to the National Resources Defense Council (NRDC), bottled water is subject to lower purity standards and is tested less frequently that city tap water for bacteria and chemical contaminants. In addition, bottled water rules allow for some contamination by E. coli or fecal coliform, contrary to tap water rules, which prohibit any confirmed contamination with these bacteria. Similarly, there are no requirements for bottled water to be disinfected or tested for parasites such as cryptosporidium or giardia, unlike the rules for big city tap water systems that use surface water sources.

Cost should also be considered. At just 10 to 20 cents per gallon, tap water from your faucet is the cheapest source of water in the U.S. According to calculations by the NRDC, bottled water can cost from 240 to 10,000 times more per gallon than water from the faucet.

Bottom line: Don’t be fooled by bottled water packaging featuring pristine glaciers and crystal-clear mountain springs.  Tap water is generally safer and definitely cheaper. 

(Sources: National Geographic’s Green Guide, Natural Resources Defense Council)  

Q: I’ve been hearing a lot about the benefits of hydrogen peroxide. Can you tell me more about common uses for it?
 
A: Hydrogen Peroxide, chemically known as H₂O₂, is readily and inexpensively available in most drugstores in a 3% or 6% concentration.  It is often sold in brown bottles and is clear, water like in appearance, and has a pungent odor. According to the U.S. Environmental Protection Agency (EPA), hydrogen peroxide breaks down rapidly in the environment to oxygen and water, and is not expected to cause adverse effects to humans or the environment when users follow label directions.
 
At the common over-the-counter concentration, hydrogen peroxide may be used safely as a disinfecting, bleaching, and deodorizing agent.
 
Here are some examples:

• Pour hydrogen peroxide on your tabletops or cutting boards to kill salmonella and other bacteria. The EPA has approved H₂O₂ as a sanitizer.
• Apply hydrogen peroxide directly to laundry stains or use in the bleach cycle of your washing machineH₂O₂ is a great alternative to chlorine bleach. 
• Mix an ounce of H₂O₂ with a cup of water and spray on your houseplants to promote growth, aerate the soil, and kill unwanted funguses.

Bottom line: You will find hydrogen peroxide in my medicine cabinet, laundry room, and kitchen pantry.  When used properly hydrogen peroxide can be a safe, versatile, and inexpensive household product.   

Q: I am overwhelmed by the choices of dishwashing liquid in the store aisle. Can you help me choose the most effective and earth friendly option? 

A: Indeed, there are so many dishwashing liquids to choose from it can be confusing to know which one to purchase, especially when you add environmental impact to the equation. Hopefully this response will help you clean up your act!  

First, choose a dishwashing liquid that is made from plant based ingredients over petroleum based ingredients. The plant based dishwashing liquid is made from a renewable resource and requires less energy in the overall manufacturing process.  

Next, opt for a dishwashing liquid that is completely biodegradable and uses no phosphates. This insures that our waterways are not adversely effective by the product. Also, you should look for full ingredient disclosure. This means the manufacturer lists every single ingredient in the product. Surprisingly, in the Unites States, the law does not require this.  

Avoid dishwashing liquid loaded with artificial fragrances, which contribute to allergic reactions, and skin irritations. Of particular concern are phalates, a hidden ingredient found in synthetic fragrances. Studies have linked phalates to hormone disruption and reproductive disorders.  

Remember to consider packaging when choosing a dishwashing liquid. Choose a product in a bottle that can be recycled in your community. Better yet, find a product that is made in a recycled bottle. Also, find the most concentrated liquid available, so that you do not have to use too many battles over the course of a year.  

There are a number of earth conscious and effective dishwashing liquids currently on the market. You might consider: Biokleen, Citra-Solv, Ecover, Mrs. Meyer’s, and Shaklee.  

Climate Change Q&A

These questions are representative of the types of inquiries we get at Green Gatherings® and other Olivine™ programs. The answers come from Climate Central, but are edited to be shorter.

Q: What is the greenhouse effect?

A: An ordinary greenhouse keeps plants warm in winter without using a heater. It works because the Sun’s rays shine through the glass walls and roof, warming the inside—and that same glass keeps the heat from escaping.

The greenhouse effect warms the Earth (and other planets) in a similar way, although it is not exactly the same. The Earth’s transparent atmosphere lets sunlight through to warm the ground and the oceans (more when it is clear, less when it is cloudy). The Earth’s warmed surface releases some of that heat in the form of infrared radiation—a form of light, but invisible to human eyes.

This infrared light wants to keep on going, right back out into space, taking the warmth with it. But some gases in the atmosphere—most importantly carbon dioxide, or CO2, but also methane, nitrous oxide, and water vapor—will not let all the infrared radiation pass through. These “greenhouse gases” are very good at absorbing infrared light. They spread the heat back to the land and the oceans. So greenhouse gases act sort of (though not exactly) like the glass in the greenhouse. They let sunlight through on its way in from space, but intercept some of the infrared light on its way back out.

As a result, the lower part of the atmosphere stays much warmer than it would otherwise. Greenhouse gases are a natural part of Earth’s atmosphere, and it’s a good thing they are! Without them, the average surface temperature of the Earth would be about 33°C (60°F) lower than it is now, and life as we know it would be impossible.

Climate scientists know how the natural greenhouse effect works on Earth and other planets. That is why they worry about what is happening as humans change the balance of greenhouse gases, for example by burning fossil fuels that release more CO2 to the air than what is released naturally.

(This answer comes from Climate Central, but is edited to be shorter.)

Q: We have had a cold winter. Does that mean the overall trend for global warming is over?

A: No.

Weather conditions at specific locations, including temperature, are dynamic and vary with regional and hemispheric weather patterns. The average global air temperature, which is the sum of regional temperatures, has been gradually rising over the past 100 years. According to NASA, the ten warmest years on record have occurred since 1997. The Fourth Assessment of the Intergovernmental Panel on Climate Change, or IPCC, reported in 2007 that 11 out of 12 of the years from 1995 to 2006—the exception being 1996—are 11 of the 12 warmest years since 1850.

Despite the current global warming trend, it is important to remember that not all parts of the Earth warm equally or at the same rate. The Arctic, for example, is warming faster than other areas, while the equatorial region is warming much more slowly.

So, while measurements show that the average temperature of the planet has risen over the past century and likely will keep rising over the next 100 years, we should not expect every year to be warmer than the year before at every spot on the Earth. In some places, and even for the Earth as a whole, there may be years when it is actually a little cooler than the previous year. Nevertheless, the data indicates that over the long term, we’re heading toward a hotter world.

(This answer comes from Climate Central, but is edited to be shorter.)

Q: What is the difference between global warming and climate change?

A: Depending on who is talking, there can be an enormous difference between global warming and climate change—or no difference at all.

A lot of people, including many journalists who write about the topic, use the two terms interchangeably. When reporters first began doing stories back in the late 1980s about how humans seemed to be doing things that result in heating up the planet, the term they usually used was global warming. That’s because the basic effect of greenhouse gases like carbon dioxide is to do exactly that. They trap more and more of the Sun’s energy and drive the average temperature of the planet upward.

But that is only one dimension of the issue. Average temperature is global. Climate is local, and involves not just average temperature, but also other factors that vary, such as humidity, cloudiness, rain (or snow), how this precipitation is spread throughout the year (does it mostly come in one short burst, or over a rainy season, or evenly all year long, or something in between?)

Scientists have learned that raising the Earth’s temperature is very likely to change many of these factors. So while global warming is what’s causing it, what most people are going to notice is not necessarily warming but rather a change in climate.

There is one more factor. Some people want to emphasize the potentially serious consequences of the problem. Others want to convince everyone to think that it is not such a big deal, or that humans are not really causing the problem in the first place. So they choose one term or the other because they think it sounds more or less scary. But since nobody can agree about which term actually is scarier, both groups use both terms at different times.

That sounds pretty confusing. The bottom line is that while global warming is not wrong, climate change more accurately describes what is happening. That is a major reason that many people have settled on the latter term.

But most of the time, whether people use global warming or climate change, they’re almost certainly talking about the same thing.

(This answer comes from Climate Central, but is edited to be shorter.)

Q: What could the effects of climate change be?

A: To start with, scientists expect sea level to rise by three feet or more—partly because water expands as it warms, partly due to melting ice in Greenland and other places. Low-lying areas—significant parts of states like Florida, and entire countries like Bangladesh and the Maldives will be more prone to erosion and to catastrophic flooding.

The warming could also make the most powerful of tropical storms even more powerful. And rainstorms in general are likely to become more intense, with more of them causing damaging floods.

As mountain glaciers melt, they will cause even more flooding—at first. But if they shrink enough, the fresh water they provide will become scarce. Billions of people in India and China, for example, depend on water that comes off glaciers in the Himalayas and the Tibetan Plateau. In the U.S., earlier snowmelt in the Rocky and Sierra Nevada mountains will mean less meltwater for a thirsty California during the summer when it is really needed.

In already arid regions like Australia and the American West, droughts are likely to come more often and be more severe. That is likely to lead to more wildfires. Heat waves will be more frequent too, in temperate zones, including most of the continental U.S.

All of these changes would affect people’s comfort and their physical safety. But they could have an even greater impact on other species. Plants and animals thrive in specific climate conditions and cannot easily adapt to rapid changes.

About our expert

Margaret Presley is an Environmental Educator who lives in Maryland with her husband and 2 young children. She has a Master’s Degree in Environmental Studies (MLA) and has prepared curricula in the areas of environmental and value education.

Her professional experience has included time with a nature center, science museum, and several schools, and she has worked with families, youth and adults of all ages in various formal and informal settings.

With a busy household and working schedule, she is quite familiar with the challenges of balancing the desire to do the “right thing” environmentally with the reality of finances, resources, and time!

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