Questions and answers about the environment.

Dear EarthTalk: I’ve been hearing about the great gas mileage for Volkswagens that use diesel fuel. But is it better for the environment to use diesel or unleaded gasoline? – K. Cronk, Bay City, MI In the past, diesel fuel was always considered dirtier than gasoline. But newer standards regulating sulfur content and improved technology in [...]

Dear EarthTalk: What is happening with various programs initiated over the years in the U.S. to return to the wild certain animal species that had been endangered or threatened? And do environmentalists tend to be for or against such efforts? — Susan Adams, Owl’s Head, ME From the standpoint of species and ecosystem health, limited [...]

Dear EarthTalk: Many people oppose dams because they change the flow of rivers and affect the migrating patterns of fish and other species, but aren’t they also a great renewable energy source? — Ryan Clark, Milton, WA Hydroelectric dams are among the greenest and most affordable electricity sources in the world—and by far the most [...]

Dear EarthTalk: I always thought cotton was eco-friendly, but I recently heard otherwise. What’s so bad about cotton? And where can I find organic cotton clothing? – Jamie Hunter, Twin Falls, ID There’s a lot “bad” about conventionally grown cotton—cotton grown with the aid of synthetic chemicals, that is. The Organic Trade Association (OTA), a [...]

Dear EarthTalk: What are the most important foods to buy organic? – Rachel Klepping, Bronxville, NY Given the usual higher prices of organic versus conventionally-grown foods, it can be a challenge to get the biggest bang for our buck while eating healthy and avoiding the ingestion of synthetic chemicals along with our nutrients. One approach, [...]

Dear EarthTalk: I heard that some wind farms use fossil fuels to power their generators when the wind won’t. Doesn’t that defeat their whole renewable energy purpose? Why not let the wind power it or not? Also, I’ve heard that the low-frequency sounds generated by these turbines can harm people and animals. Is this true? [...]

Dear EarthTalk: Within my lawn I have over 100 citrus, mango and avocado trees. When I use Scott’s Bonus S Weed and Feed, am I feeding my new fruit any poison? Will the weed killer be taken up by the fruit? – Richard Weissman, Miami, FL In short, yes and yes: You will jeopardize the [...]

Dear EarthTalk: I am a bartender and I would love to be able to use some sort of locally made or sustainable version of sugar. What’s out there? – Ryan Seng, via e-mail It sure would be nice if we could obtain all of our food and drink items from local sources, but sugar provides an [...]

Dear EarthTalk: Is it true that bananas are taboo for anyone who is concerned about rainforest destruction? Even if I seek out “fair trade” or organic bananas, am I feeding the demand which is causing rainforest to be cleared? – Laura Barnard, Hillsboro, OH Sadly, the short answers to these questions may be yes and [...]

Dear EarthTalk: What is “kenaf” paper? From what I’ve heard, it’s good for the environment. But what exactly are its benefits and where can I obtain some? – Tiffany Mikamo, via e-mail Kenaf, a fast-growing, non-invasive annual hibiscus plant related to cotton, okra and hemp, makes ideal paper fiber as well as great source material [...]

Dear EarthTalk: Is it true that the BP oil leak is much more of an environmental threat than previous spills from tankers, and if so why? – Nathan Gore, Pawtucket, RI No one knows for sure how the ongoing oil catastrophe in the Gulf of Mexico will affect the deep sea ecosystem, but scientists are [...]

Dear EarthTalk: The U.S. got socked with several major storms this past winter. Local weather reports never mentioned this as odd. But is it a sign of global warming? – R.A. Forbes, via e-mail Weather patterns and trends are notoriously unpredictable, varying due to a great many different inputs. While it’s true that snowier, stormier [...]

Dear EarthTalk: Can airplanes be run on cleaner fuels or be electric powered? Are there changes afoot in the airline business to find cleaner fuels? – Reema Islam, Dhaka, Bangladesh Given air travel’s huge contribution to our collective carbon footprint—flying accounts for about three percent of carbon emissions worldwide by some estimates—and the fact that [...]

Dear EarthTalk: I heard that Walmart is having a bigger positive impact on the environment than any other U.S. institution. What are they doing along these lines?  — R. Schlansker, Beaverton, OR Walmart has indeed been working to clean up its image in recent years, and many environmentalists are pleased with the company’s commitment to [...]

Dear EarthTalk: I’m told that, despite improvements in recent years, pesticides in flea collars are still harmful to pets and humans. Are there ways to minimize fleas without resorting to chemical concoctions? And is anything being done to ban these dangerous products from store shelves? – Nancy Trouffant, Lancaster, PA Americans spend some $1 billion [...]