A solid majority, 71 percent of Americans, believe the country “should do whatever it takes to protect the environment,” according to a 2014 poll by the Pew Research Center.
This strong public interest in our environment extends to urban living, prompting NerdWallet’s curiosity: Even though we all know that the city we live in influences our transportation and energy choices, how do environmental impacts differ across the U.S.?
We explored the data for the nation’s 150 largest cities to shed light on the best places for those seeking a green lifestyle and a healthy environment.
Photo credit: Shutterstock
Environmental quality: To uncover the impact of pollution on residents’ health, we looked at each city’s 2014 median of the U.S. Environmental Protection Agency’s daily Air Quality Index—a measure of sulfur dioxide, carbon monoxide, nitrogen dioxide and ozone levels that guide the assessment of acute health effects. The higher the index number, the more polluted an area. In most cases, air quality in U.S. cities has a median index score under 100, which falls into the EPA’s “moderate” range.
Transportation: To understand how cities might influence lifestyle choices, we looked at data from the U.S. Census Bureau’s American Community Survey on commuting methods to find out how many workers are walking, biking, carpooling and taking public transit.
Energy sources: To gain insight into the fuels people are using in each city, we looked at data from the American Community Survey on heating in homes. We were specifically interested in the number of homes using coal and wood because these fuels are particularly harmful. We also examined the use of solar energy because of its sustainability.
Housing density: Urban sprawl increases transportation needs and resource use, so we looked at data from the American Community Survey on the percentage of residential buildings with 10 or more residences in each city.
What we learned
Bigger is better: We might associate larger cities with polluting industries, but bigger cities tend to be denser, which reduces urban sprawl and energy needs for transportation per capita.
Air quality is fairly uniform: Many of the cities we examined fall within a narrow range of the EPA’s Air Quality Index, sitting between the classification of “good,” an index number under 51, and “moderate,” a number under 101. Of course, there are notable outliers, like Riverside, California, where the air quality about 30 days in 2014 reached “unhealthy” levels over 150.
Traditional fuels remain: While solar power is part of mainstream energy conversations, the data suggest adoption is lagging. Nationwide, out of 116 million homes, only 72,707 houses use solar heating, up from 2005 when the number was 36,682. While the use of traditional heating methods—including coal and wood burning—have remained stable.
America’s top 10 greenest cities
1. Honolulu, Hawaii
This city in the nation’s 50th state tops our list with its air quality, the best of all the cities we analyzed, and for residents’ widespread use of solar energy. In 2014, the city received the EPA’s highest classification of “good” for 351 of the 360 days measured, giving it a median Air Quality Index of 27 for the year.
2. Washington, DC
The national’s capital lands near the top of our list probably because of its excellent public transit, which carries 38 percent of commuters to work. Other highlights include the city’s low levels of pollution from heating fuels, such as coal and wood, in the dense city.
3. Arlington, Virginia
With a slightly higher number of dense residential buildings, but fewer commuters who walk or take public transportation, Arlington comes in just below its neighbor. Given their proximity, it isn’t surprising that Washington, DC and Arlington share a median Air Quality Index of 48, which is just within the EPA’s “good” classification.
4. San Francisco, California
San Francisco, long known as a center of activism around sustainability, scores well in terms of transportation, with 10 percent of commuters walking in the hilly city to work. The city also shines in terms of solar energy use, with slightly over 13.8 of every 10,000 homes using the sun’s energy for heat. In comparison, 6.25 of every 10,000 homes use solar heating nationwide.
5. Miami, Florida
When it comes to healthy air quality and the number of residents who carpool, Miami shines. But in this city, fewer commuters use public transportation. Only 11 percent of residents commute on transit, one of the lowest public transportation figures in our top 10.
6. New York City, New York
It’s big and a lot of people live here, but New York City’s density is why it made our list. Many of the city’s over 8 million residents walk to work while still more use the city’s comprehensive public transit system. However, 7.2 of every 10,000 homes still use coal for heat.
7. Boston, Massachusetts
More of Boston’s residents walk to work than in any other city on our top 10 list: 15 percent of Bostonians brave the seasons, including the harsh winter, on foot.
8. Orlando, Florida
Like Miami, Orlando does well when it comes to air quality, with only one day in 2014 with unhealthful air. The quality of air here isn’t surprising, since residents don’t use coal and they burn little wood for heat.
9. Seattle, Washington
While the city’s gray skies limit use of solar energy, Seattle makes our list for its air quality, high residential density and commuters who walk and use public transit at above-average rates. In the Emerald City, nine percent of workers walk to their jobs and four percent commute on a bike.
10. Jersey City, New Jersey
The city shares a mediocre air quality index with its neighbor New York City. However, Jersey City also shares a positive trend: residents use public transit at far above-average rates. At least 46 percent of workers living in Jersey City commute on public transit, second only to New York City’s 56 percent.
Top 25 greenest cities in America
The score for each city was calculated from the following measures:
1. The 2014 Median Air Quality Index from the U.S. Environmental Protection Agency. This is 25 percent of a city’s score.
2. The percentage of workers who carpool, bike, walk or use public transit to commute to work from the U.S. Census Bureau’s 2013 American Community Survey. Together the transportation variables are 25 percent of a city’s score.
3. The percentage of occupied buildings with 10 or more residents is from the 2013 American Community Survey, this was 25 percent of a city’s score.
4. The number of residential buildings with a primary heat source of solar, coal or wood per 10,000 buildings is from the 2013 American Community Survey. Solar was taken as a positive variable and accounted for 8.33 percent of the final score while coal and wood heat sources were treated as negative and were 16.67 percent of a city’s final score.
Note: Newark, New Jersey, was originally ranked 24th, but because of environmental hazards outside the scope of the study, the city was omitted from the final list.
YOU MIGHT ALSO LIKE
EcoWatch Daily Newsletter
By Jake Johnson
In a move that environmentalists warned could further imperil hundreds of endangered species and a protected habitat for the sake of profit, President Donald Trump on Friday signed a proclamation rolling back an Obama-era order and opening nearly 5,000 square miles off the coast of New England to commercial fishing.
Why You Should Wash Fresh Produce<p>Global pandemic or not, properly washing fresh fruits and vegetables is a good habit to practice to minimize the ingestion of potentially harmful residues and germs.</p><p>Fresh produce is handled by numerous people before you purchase it from the grocery store or the farmers market. It's best to assume that not every hand that has touched fresh produce has been clean.</p><p>With all of the people constantly bustling through these environments, it's also safe to assume that much of the <a href="https://www.healthline.com/nutrition/fresh-vs-frozen-fruit-and-vegetables" target="_blank">fresh produce</a> you purchase has been coughed on, sneezed on, and breathed on as well.</p><p>Adequately washing fresh fruits and vegetables before you eat them can significantly reduce residues that may be left on them during their journey to your kitchen.</p><p><strong>Summary</strong></p><p><strong></strong>Washing fresh fruits and vegetables is a proven way to remove germs and unwanted residues from their surfaces before eating them.</p>
Best Produce Cleaning Methods<p>While rinsing fresh produce with water has long been the traditional method of preparing fruits and veggies before consumption, the current pandemic has many people wondering whether that's enough to really clean them.</p><p>Some people have advocated the use of soap, <a href="https://www.healthline.com/nutrition/white-vinegar" target="_blank">vinegar</a>, lemon juice, or even commercial cleaners like bleach as an added measure.</p><p>However, health and food safety experts, including the Food and Drug Administration (FDA) and Centers for Disease Control (CDC), strongly urge consumers not to take this advice and stick with plain water.</p><p>Using such substances may pose further health dangers, and they're unnecessary to remove the most harmful residues from produce. <a href="https://www.healthline.com/health/chlorine-poisoning" target="_blank">Ingesting commercial cleaning chemicals</a> like bleach can be lethal and should never be used to clean food.</p><p>Furthermore, substances like lemon juice, vinegar, and produce washes have not been shown to be any more effective at cleaning produce than plain water — and may even leave additional deposits on food.</p><p>While some research has suggested that using neutral electrolyzed water or a baking soda bath can be even more effective at removing certain substances, the consensus continues to be that cool tap water is sufficient in most cases.</p><p><strong>Summary</strong></p><p><strong></strong>The best way to wash fresh produce before eating it is with cool water. Using other substances is largely unnecessary. Plus they're often not as effective as water and gentle friction. Commercial cleaners should never be used on food.</p>
How to Wash Fruits and Vegetables With Water<p>Washing fresh fruits and vegetables in cool water before eating them is a good practice when it comes to health hygiene and food safety.</p><p>Note that fresh produce should not be washed until right before you're ready to eat it. Washing fruits and vegetables before storing them may create an environment in which bacterial growth is more likely.</p><p>Before you begin washing fresh produce, <a href="https://www.healthline.com/health/how-long-should-you-wash-your-hands" target="_blank">wash your hands well</a> with soap and water. Be sure that any utensils, sinks, and surfaces you're using to prepare your produce are also thoroughly cleaned first.</p><p>Begin by cutting away any bruised or visibly rotten areas of fresh produce. If you're handling a fruit or vegetable that'll be peeled, such as an orange, wash it before peeling it to prevent any surface bacteria from entering the flesh.</p><p>The general methods to wash produce are as follows:</p><ul><li><strong>Firm produce.</strong> Fruits with firmer skins like apples, lemons, and pears, as well as <a href="https://www.healthline.com/nutrition/root-vegetables" target="_blank">root vegetables</a> like potatoes, carrots, and turnips, can benefit from being brushed with a clean, soft bristle to better remove residues from their pores.</li><li><strong>Leafy greens.</strong> Spinach, lettuce, Swiss chard, leeks, and cruciferous vegetables like Brussels sprouts and bok choy should have their outermost layer removed, then be submerged in a bowl of cool water, swished, drained, and rinsed with fresh water.</li><li><strong>Delicate produce.</strong> Berries, mushrooms, and other types of produce that are more likely to fall apart can be cleaned with a steady stream of water and gentle friction using your fingers to remove grit.</li></ul><p>Once you have thoroughly rinsed your produce, dry it using a clean paper or cloth towel. More fragile produce can be laid out on the towel and gently patted or rolled around to dry them without damaging them.</p><p>Before consuming your fruits and veggies, follow the simple steps above to minimize the amount of germs and substances that may be on them.</p><p><strong>Summary</strong></p><p><strong></strong>Most fresh fruits and veggies can gently be scrubbed under cold running water (using a clean soft brush for those with firmer skins) and then dried. It can help to soak, drain, and rinse produce that has more dirt-trapping layers.</p>
The Bottom Line<p>Practicing good food hygiene is an important health habit. Washing fresh produce helps minimize surface germs and residues that could make you sick.</p><p>Recent fears during the <a href="https://www.healthline.com/coronavirus" target="_blank">COVID-19 pandemic</a> have caused many people to wonder whether more aggressive washing methods, such as using soap or commercial cleaners on fresh produce, are better.</p><p>Health professionals agree that this isn't recommended or necessary — and could even be dangerous. Most fruits and vegetables can be sufficiently cleaned with cool water and light friction right before eating them.</p><p>Produce that has more layers and surface area can be more thoroughly washed by swishing it in a bowl of cool water to remove dirt particles.</p><p>Fresh fruits and vegetables offer a number of healthy nutrients and should continue to be eaten, as long as safe cleaning methods are practiced.</p>
- 30 Awesome Ways to Use Apple Cider Vinegar Everyday - EcoWatch ›
- Here's How to Clean Your Groceries During the COVID-19 Outbreak ... ›
- 5 Facts You Should Know About Pesticides on Fruits and Vegetables ›
By Danielle Nierenberg
Following the murder of George Floyd by police in Minneapolis, people around the United States are protesting racism, police brutality, inequality, and violence in their own communities. No matter your political affiliation, the violence by multiple police departments in this country is unacceptable.
Mangroves play a vital role in capturing carbon from the atmosphere. Mangrove forests are tremendous assets in the fight to stem the climate crisis. They store more carbon than a rainforest of the same size.
- Protecting Mangroves Can Prevent Billions of Dollars in Global ... ›
- Could the 'Mangrove Effect' Save Coasts From Sea Level Rise ... ›
Monday is World Oceans Day, but how can you celebrate our blue planet while social distancing?
- 5 Things to Know About Earth's Warming Oceans - EcoWatch ›
- Bioluminescent Waves Mesmerize California Beachgoers, Surfers ... ›
- NOAA: 2020 Could Be Warmest Year on Record - EcoWatch ›
- On June 8, We Celebrate Our Oceans, Our Future - EcoWatch ›
- 5 Things to Know About the State of Our Oceans for World Oceans Day ›
By Jacob L. Steenwyk and Antonis Rokas
From the mythical minotaur to the mule, creatures created from merging two or more distinct organisms – hybrids – have played defining roles in human history and culture. However, not all hybrids are as fantastic as the minotaur or as dependable as the mule; in fact, some of them cause human diseases.
When Looking Through a Microscope Isn’t Close Enough.<p>For the last few years, <a href="http://www.rokaslab.org/" target="_blank">our team at Vanderbilt University</a>, <a href="https://www.researchgate.net/lab/Gustavo-Goldman-Lab" target="_blank">Gustavo Goldman's team at São Paulo University in Brazil</a> and many other collaborators around the world have been collecting samples of fungi from patients infected with different species of <em>Aspergillus</em> molds. One of the species we are particularly interested in is <a href="https://doi.org/10.1006/rwgn.2001.0082" target="_blank"><em>Aspergillus nidulans</em>, a relatively common and generally harmless fungus</a>. Clinical laboratories typically identify the species of <em>Aspergillus</em> causing the infection by examining cultures of the fungi under the microscope. The problem with this approach is that very closely related species of <em>Aspergillus</em> tend to look very similar in their broad morphology or physical appearance when viewing them through a microscope.</p><p>Interested in examining the varying abilities of different <em>A. nidulans</em> strains to cause disease, we decided to analyze their total genetic content, or genomes. What we saw came as a total surprise. We had not collected <em>A. nidulans</em> but <em>Aspergillus latus</em>, a close relative of <em>A. nidulans</em> and, as we were to soon find out, <a href="https://doi.org/10.1016/j.cub.2020.04.071" target="_blank">a hybrid species that evolved through the fusion of the genomes</a> of two other <em>Aspergillus</em> species: <em>Aspergillus spinulosporus</em> and an unknown close relative of <em>Aspergillus quadrilineatus</em>. Thus, we realized not only that these patients harbored infections from an entirely different species than we thought they were, but also that this species was the first ever <em>Aspergillus</em> hybrid known to cause human infections.</p>
Several Different Fungal Hybrids Cause Human Disease.<p>Hybrid fungi that can cause infections in humans are well known to occur in several different lineages of single-celled fungi known as yeasts. Notable examples include multiple different species of <a href="https://doi.org/10.1002/yea.3242" target="_blank">yeast hybrids</a> that cause the human diseases <a href="https://rarediseases.info.nih.gov/diseases/6218/cryptococcosis" target="_blank">cryptococcosis</a> and <a href="https://www.cdc.gov/fungal/diseases/candidiasis/index.html" target="_blank">candidiasis</a>. Although pathogenic yeast hybrids are well known, our discovery that the <em>A. latus</em> pathogen is a hybrid is a first for molds that cause disease in humans.</p>
(Left) Candida yeasts live on parts of the human body. Imbalance of microbes on the body can allow these yeasts, some of which are hybrids, to grow and cause infection. (Right) Cryptococcus yeasts, including ones that are hybrids, can cause life-threatening infections in primarily immunocompromised people. Centers for Disease Control and Prevention<p><a href="https://doi.org/10.1371/journal.ppat.1008315" target="_blank">Why certain <em>Aspergillus</em> species are so deadly</a> while others are harmless remains unknown. This may in part be because <a href="https://doi.org/10.1016/j.fbr.2007.02.007" target="_blank">combinations of traits, rather than individual traits</a>, underlie organisms' ability to cause disease. So why then are hybrids frequently associated with human disease? Hybrids inherit genetic material from both parents, which may result in new combinations of traits. This may make them more similar to one parent in some of their characteristics, reflect both parents in others or may differ from both in the rest. It is precisely this mix and match of traits that hybrids have inherited from their parental species that <a href="https://www.nytimes.com/2010/09/14/science/14creatures.html" target="_blank">facilitates their evolutionary success</a>, including their ability to cause disease.</p>
The Evolutionary Origin of an Aspergillus Hybrid.<p>Multiple evolutionary paths can lead to the emergence of hybrids. One path is through mating, just as the horse and donkey mate to create a mule. Another path is through the merging or fusion of genetic material from cells of different species.</p><p>It is this second path that appears to have been taken by our fungus. <em>A. latus</em> appears to have two of almost everything compared to its parental species: twice the genome size, twice the total number of genes and so on. But unlike other hybrids, which are often sterile like the mule, we found that <em>A. latus</em> is capable of reproducing both asexually and sexually.</p><p>But how distinct were the parents of <em>A. latus</em>? By comparing the parts contributed by each parent in the <em>A. latus</em> genome, we estimate that its parents are approximately 93% genetically similar, which is about as related as we humans are with lemurs. In other words, <em>A. latus</em>, an agent of infectious disease, is the fungal equivalent of a human-lemur hybrid.</p>
How A. Latus Differs From its Parents.<p>Elucidating the identity of closely related fungal pathogens and how they differ from each other in infection-relevant characteristics is a key step toward reducing the burden of fungal disease. For example, we found that <em>A. latus</em> was three times more resistant than <em>A. nidulans</em>, the species it was originally identified as using microscopy-based methods, to one of the most common antifungal drugs, <a href="https://www.drugbank.ca/drugs/DB00520" target="_blank">caspofungin</a>. This result provides a clear example of the potential importance of accurate identification of the <em>Aspergillus</em> pathogen causing an infection.</p><p>We also examined how <em>A. latus</em> and <em>A. nidulans</em> interact with cells from our immune system. We found that immune cells were less efficient at combating <em>A. latus</em> compared to <em>A. nidulans</em>, suggesting the hybrid fungus may be trickier for our immune systems to identify and destroy.</p><p>In the midst of the COVID-19 pandemic, our quest to understand <em>Aspergillus</em> pathogens is becoming more urgent. Growing evidence suggests that <a href="https://doi.org/10.1111/myc.13096" target="_blank">a fraction of COVID-19 patients are also infected with <em>Aspergillus</em>.</a> More worrying is that these <a href="https://doi.org/10.3201/eid2607.201603" target="_blank">secondary <em>Aspergillus</em> infections</a> can worsen the clinical outcomes for those infected with the novel coronavirus. That being said, we stress that little is known about <em>Aspergillus</em> infections in COVID-19 patients due to a lack of systematic testing, and none of the infections identified so far appear to have been caused by hybrids.</p><p>So, when it comes to hybrids, some are fantastic (the minotaur), some are helpful (the mule) and some are dangerous (<em>Aspergillus latus</em>). Understanding more about the biology of <em>Aspergillus latus</em> may help in our understanding of how microbial pathogens arise and how to best prevent and combat their infections.</p>
This Saturday, June 6, marks National Trails Day, an annual celebration of the remarkable recreational, scenic and hiking trails that crisscross parks nationwide. The event, which started in 1993, honors the National Trail System and calls for volunteers to help with trail maintenance in parks across the country.
- As Protests Rage, Climate Activists Embrace Racial Justice ... ›
- First-Ever Black Birders Week Tackles Racism Outdoors - EcoWatch ›
- 15 EcoWatch Stories on Environmental and Racial Injustice ... ›
- Take a Hike Day Is Around the Bend. What's Your Dream Hike ... ›