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From the Editors of E/The Environmental Magazine

Dear EarthTalk: Is the pressure-treated wood used for decks, picnic tables and backyard play structures harmful to human health? -- Christy Silver, Cleveland, OH

Pressure-treated wood contains the preservative chromated copper arsenate (CCA), an arsenic derivative that is used to protect the wood and prolong its life. Also used commercially as a pesticide, CCA is regarded by many homeowners and construction professionals as a godsend for preserving outdoor wood structures against harsh weather and termites. But it is also on environmentalists’ watch lists as a potential health hazard due to its arsenic content.

According to the US Environmental Protection Agency (EPA), arsenic, although a naturally occurring element found in the Earth’s crust, is poisonous. Prolonged exposure can cause vomiting, diarrhea and skin abnormalities. The EPA also considers arsenic to be a human carcinogen, with long-term exposure increasing the risk of skin cancer and tumors of the bladder, kidney, liver and lung.

Recent studies have shown that rainwater can release arsenic-laden CCA from the treated wood, potentially contaminating any soil or groundwater below. Also, especially after a heavy rain, a fine coating of CCA residue can build up directly on the wood’s surface, which in turn can be picked up on hands and clothing, potentially exposing family members to small but persistent doses of arsenic.

But while the EPA may classify arsenic itself as a toxin, it does not believe that periodic contact with pressure-treated wood poses any “unreasonable” risk. The agency has, however, issued new safeguards for protecting workers who come into contact with CCA on a daily basis. Even the nation’s largest producer of pressure treated wood, Arch Wood Protection Inc., advises taking precautions when working with, using and cleaning up its products, acknowledging that “exposure to CCA may present certain hazards.”

If you already have pressure treated wood around your home, applying an oil-based stain once every couple of years will help keep the CCA from seeping out. Additionally, you should keep children and pets out of under-deck areas where arsenic may be present. Also, don’t grow edible plants near any pressure treated wood structures, and always follow safe handling guidelines (including the use of gloves and dust masks) when using it in building projects.

For those who may be starting from scratch, there are several safer alternatives to pressure treated wood. According to the Berkeley, California based Green Resource Center, yellow cypress, yew, tamarack, hemlock, white cedar and redwood are naturally rot-resistant, as are plastic and wood-plastic composite building materials. Meanwhile, wood boards that are treated with alternative techniques that don’t use CCA are free of the arsenic problem. Alkaline Copper Quartenary, sold under the trade name NatureWood, is one safer option, as is Copper Azole, which is sold under the trade name Natural Select.

CONTACTS: EPA Arsenic Toxicity Assessment, www.epa.gov/ttn/atw/hlthef/arsenic.html; Green Resource Center, (510) 845-0472, www.greenresourcecenter.org; NatureWood, (800) 241-0240, www.osmose.com/wood/usa/preserved/naturewood/product/; Natural Select, (866) 789-4567, www.naturalselect.com.

Why have shark attacks been on the rise in recent years? -- J. Tibbetts, Boston, MA

Despite a slight downturn during the last few years as a result of hurricanes keeping people out of the water, the number of shark attacks on humans has indeed risen steadily over the last century. In fact, the nearly 500 shark attacks recorded around the world in the 1990s was double that which occurred in the previous decade, and that trend seems to be continuing apace into the new millennium.

The largest increase in shark attacks has been along the southeastern seaboard of the United States. The summer of 2001 witnessed sharks moving in to shallower waters and striking people near the shoreline. In just three weeks there were 20 attacks and two deaths--often in water no more than three feet deep.

The largest increase in shark attacks has been along the southeastern seaboard of the United States. The summer of 2001 witnessed sharks moving in to shallower waters and striking people near the shoreline. In just three weeks there were 20 attacks and two deaths--often in water no more than three feet deep.

Unproven theories abound regarding this phenomenon. Some experts postulate that the human-caused decline in ocean fish is causing sharks to venture closer to shore in search of food. Others believe that sharks’ territories are shifting due to changes in ocean temperatures resulting from global warming.

Whether or not these theories have merit, no one doubts that humans are venturing further and further out to sea to swim, surf, snorkel and dive, increasing the chances of run-ins with sharks. Surfers are especially at risk because their shiny black wetsuits look like tasty seals to sharks. Also, surfers spend lots of time waiting for waves in the “splash zone” just offshore, where sharks tend to congregate to look for prey.

“An ever growing number of people spend their vacation at the oceanside, so that both the probability of encountering a shark and the respective danger of an accident also increases,” says Dr. Alexander Godknecht, president of the Shark Foundation. Godknecht believes the 100 or so shark attacks last year to be a very small number and that mainstream media hype makes them appear to happen more often than they really do.

George Burgess, director of the International Shark Attack File (ISAF) at the Florida Museum of Natural History, agrees, arguing that the average North American is about 15,000 times more likely to be killed in a car accident than in a shark attack. “Bees, wasps and snakes cause far more fatalities a year,” he adds. “And the annual risk of death from lightning is 30 times greater than that from a shark attack.”

Burgess points out that, despite the increase in shark attacks, shark populations are actually in decline globally, mostly due to human overfishing which has depleted their sustenance. Along the Atlantic coast of the U.S. some shark species have declined as much as 70 percent over the last 20 years. “The number of shark attacks is rising every year while the shark population is dwindling--it’s not rocket science to see that something is provoking them. We’re swamping the near-shore environment,” Burgess concludes.

CONTACTS: Shark Foundation, www.shark.ch; International Shark Attack File, www.flmnh.ufl.edu/fish/Sharks/ISAF/ISAF.htm.

Dear EarthTalk: Which types of household products are most likely to cause chemical sensitivities? -- John Morgan, Somerville, MA

Household products trigger chemical sensitivities in hundreds of thousands of Americans every year, yet few people make the connection between their skin rash or sneezing and the bottles and cans stored under their kitchen sink or in the broom closet.

Common reactions to everyday household cleansers and other substances include migraine headaches, asthma and sinusitis, but more serious cardiovascular, neurological and autoimmune diseases may also result from prolonged use or lack of adequate ventilation in areas where these chemicals are being applied. “Early warning signs are burning and irritation of the sinuses, nose or throat--usually not with a fever--and itching or sneezing,” says Dr. Grace Ziem, a public health physician specializing in chemical injuries.

Prevention is the key. And removing toxic compounds from your home is the strategy. You can begin under the kitchen sink by replacing traditional choices with “products your grandmother bought,” says Suzanne Olson of the Environmental Health Network. “Borax, vinegar and baking soda will clean most items around the house.” Olson uses vegetable oil to polish furniture and shuns any items with a fragrance.

“If any ingredients end in ‘ethylene’ or ‘ethane,’ it’s not a healthy product,” says Cynthia Wilson of the Chemical Injury Information Network. She recommends using scent-free and dye-free laundry products, and oxygen-based whitening additives in place of toxic bleach. Two companies that supply non-toxic laundry products as well as other green-friendly household cleaners include Seventh Generation and Earth Friendly Products. You can shop both online or in natural foods markets and some supermarkets.

Synthetic home furnishings can also trigger sensitivities. Foam, particleboard and veneers can all aggravate a variety of symptoms. And sweet dreams may elude you if you have chemical sensitivities to items in your bedroom. Most mattresses are made from artificial materials, and some beds have chemical mold inhibitors while almost all have fire retardant. In order to eliminate chemical sensitivities from ruining your sleep, choose a mattress manufactured from organically grown cotton. Two good sources include Lifekind Products and Heart of Vermont; both offer secure, online ordering.

If you think some household chemicals might be bothering you, Dr. Ziem suggests keeping a log to help pinpoint the offenders. The best way to find out whether any chronic ailments you may have are caused or aggravated by household products is to take a simple inventory of the home and its contents, and replace synthetic products with natural ones wherever possible. By ridding the home of some of these culprits, you and your family are bound to breathe easier.

CONTACTS: Environmental Health Network, http://users.lmi.net/wilworks/; Chemical Injury Information Network, www.ciin.org. Seventh Generation, (800) 456-1191, www.seventhgeneration.com; Earth Friendly Products, (800) 335-3267, www.ecos.com; Lifekind, www.lifekind.com, (800) 284-4983; Heart of Vermont, (800) 639-4123, www.heartofvermont.com.

How can I recycle my outdated computer equipment? -- Kenneth Rapp, Toms River, NJ

Computers are infamous for their rapid obsolescence. These days you can expect a new computer to serve you for three to five years at best before “must have” features become available only in newer models. Many companies have “computer graveyards”--rooms filled to the ceiling with outdated computers, printers, monitors, cables and other accessories that are no longer in operation and seemingly have nowhere to go but the junk heap.

It’s no surprise then that more than 10 million computers end up in American landfills every year. But old computer equipment languishing in landfills poses myriad environmental hazards, as many contain toxic compounds that can seep into surrounding land and groundwater. According to USA Today, the average PC contains “five pounds of lead (to protect the user from radiation) in the cathode ray tube monitor alone. Circuit boards typically contain cadmium, mercury and chromium while the whole package is housed in brominated, flame-retardant plastic.” The National Safety Council reports that by the end of 2005, 350 million computers will have reached obsolescence, with at least 55 million of them expected to end up in landfills unless recycling increases.

According to Nikki and David Goldbeck’s book, Choose to Reuse, many computers can be saved and don't need to end up in landfills. The first thing to check is if your old computer can be upgraded; often the substitution of a simple memory chip can make a slowpoke speed up considerably. And RAM memory--?provided there are sufficient expansion slots--is getting cheaper all the time.

If an upgrade won't work, there are alternatives to landfills. Goodwill and The Salvation Army will take working older equipment and re-sell it. “Free Computer” ads can be posted at schools and workplaces. And brokers like American Computer Exchange will take your hardware for trade on a newer model.

Meanwhile, many worthy non-profit groups will make good use of computer equipment outdated for your needs. The National Cristina Foundation places used technology with non-profit organizations and public agencies that serve the disabled and economically disadvantaged. For a more do-it-yourself approach, The Global Crisis Solution Center provides a free online resource hooking up equipment donors with needy non-profits.

Europe is leading the way in keeping computers out of landfills, with all computer manufacturers required to have recycling programs in place. In the U.S., several makers will now recycle or exchange computers, often for a marginal fee. IBM, Dell Computer and Hewlett-Packard have all started such programs.

CONTACTS: American Computer Exchange, www.amcoex.com; National Cristina Foundation, www.cristina.org; Global Crisis Solution Center, www.globalcrisis.info/computerrecycle.html; IBM Product Recycling Program, www.ibm.com/ibm/environment/products/prp.shtml; Dell Recycling, www1.us.dell.com/content/topics/segtopic.aspx/dell_recycling; Hewlett-Packard Product Recycling, www.hp.com/hpinfo/globalcitizenship/environment/recycle/.

Dear EarthTalk: What impact does mining for diamonds and other gems have on the environment? -- Tiffany Schultz, Dayton, OH

Gem mining around the world can indeed be very destructive to the surrounding environment, leading to many problems such as soil erosion and sedimentation, water pollution and depletion, poisoning of wildlife and vegetation, flooding--even landslides. The contents of “mine tailings”--rock and other waste materials separated and left behind in the mining process--can wreak havoc on nearby agricultural lands, and pose myriad human health problems.

In the United States, mining companies are legally obligated to conduct environmental impact studies of proposed sites and then, if approved by regulators, follow the letter of the law regarding the protection of wildlife, air and water, and the proper disposal of hazardous waste. Furthermore, many U.S. states have “reclamation” laws on the books calling for the safeguarding of surface and groundwater around mining operations, and cleanup and re-vegetation after the fact to restore mining areas to their original condition.

But mines outside U.S. borders are not subject to the same rules as they are here in the U.S., even if run by American companies. Large-scale demand means large-scale mining operations, and that often means massive amounts of sedimentation and tailings falling into water systems around the world. The mercury and cyanide used to separate gold and copper from rock also make their way into our air and water.

With no country-of-origin labeling laws or system in the jewelry and gem trade, consumers can never be sure if their bracelets, rings and necklaces come from responsible sources or from companies whose mining operations are polluting, destroying wildlife habitat, exploiting poor or indigenous people (and their resources)--or funding a civil war, as does the diamond trade in Angola and Sierra Leone.

According to Friends of the Earth, mining giant Freeport-McMoRan Copper and Gold in 1996 was dumping 110,000 tons of mine tailings into the local river system on a daily basis. Plans to expand Freeport’s mining activities in Indonesia, according to the company’s own environmental auditors, could “increase its dumping of untreated tailings to 285,000 tons daily,” presenting serious health challenges for local residents who have little in the way of power or resources to halt such activity.

Obtaining jewels, however, does not have to be a destructive proposition. People have been finding valuable gems and minerals for centuries by panning for them themselves in rivers and streams. There are even “theme parks” scattered across U.S., such as Gold City, in Franklin, North Carolina, that let you “mine your own gemstones.” And companies such as Junk to Jewels and Snooty Jewelry sell jewelry made from recycled materials, handmade beads and glass. Another company, Global Marketplace, sells a wide range of jewelry made by artists in developing countries such as Nepal, Mexico and Chile, thus helping producers in these nations increase their standard of living above the poverty line.

CONTACTS: Friends of the Earth, (877) 843-8687, www.foe.org; Gold City, (800) 713-7767, www.goldcityamusement.com; Junk to Jewels, www.junktojewels.net; Snooty Jewelry, www.snootyjewelry.com; Global Marketplace, www.globalmarketplace.org.

Although salt and various salt derivatives melt ice effectively and make both walkways and roads safer, they can be damaging to the environment. After salt is applied, it washes off paved surfaces into storm drains or onto adjacent ground, and can then be carried into nearby bodies of water. According to The New York Times, this salty runoff poisons fish and wilts vegetation. It also corrodes metals, damages concrete and poses health risks to people with high blood pressure.

However, arsenic is also a by-product of industrial activity, such as coal burning, waste burning, copper smelting, and mining for gold and other metals. It is also an agricultural byproduct as it is a component of some pesticides and feed additives. U.S. smokestack and agricultural industries release thousands of pounds of arsenic into the environment each year--and as a result arsenic can show up in public water supplies in amounts that do pose health threats.

Some studies have also shown that salt applied to road surfaces increases automobile collisions with wildlife, especially white-tailed deer that are attracted to natural and artificial salt deposits in their normal course of feeding.

Despite these facts, salt remains the cheapest and most effective way to keep pavement free of ice. According to materials consultant Henry Kirchner, individuals can effectively use salt with minimum impact: “Do not use a chemical deicer to melt every bit of ice,” says Kirchner. “Use only enough to break the ice/pavement bond, then remove the remaining slush by plowing or shoveling.” All snow should be cleared away first, and the ice should be chipped off and moved away from water supplies and vegetation.

For small jobs, it may be feasible to use more potent, less environmentally toxic de-icers like magnesium chloride or calcium magnesium acetate instead of rock salt. These stronger, though more expensive, compounds can be strategically applied before a storm to block ice from forming. Sand and cat litter can be used to provide temporary traction, but these materials may dog surface water and bury plants. Although many researchers are experimenting with even more benign de-icers, including by-products of corn and cheese processing, none of these compounds is currently available to consumers.

Perhaps the larger issue is how municipalities store and use large amounts of road salt. Many of the most severe cases of environmental contamination have been caused by improper storage. When salt is stored outside uncovered, rain and snow can carry large quantities to surrounding soil and water.

As to reducing salt use, many cities and towns simply don’t de-ice in flat residential areas, except during ice storms. Some use a mix of sand and salt, instead of pure salt. Also, salt spreading equipment that is well maintained will distribute salt more accurately and, as a result, use less. Additionally, salt that is wetted before being spread sticks better to the road.

According to the trade magazine, Better Roads, a product called Verglimit, a mixture of de-icing salts and caustic soda, can be mixed with asphalt roadway during paving. Its installation doubles the cost of surfacing a road, but helps reduce the amount of salt needed for de-icing roadways and, according to the magazine, “in certain conditions can eliminate the need for salting entirely.”

CONTACTS: The Salt Institute, (703) 549-4648, www.saltinstitute.org; Better Roads, “Materials for Deicing and Anti-icing,” www.betterroads.com/articles/NewProds/Apr03bid.htm.

Dear EarthTalk: I have developed asthma from the fiberglass insulation in our home. How can I find insulation that won’t make me sick? -- Cynthia Bacon, Orlando, FL

Fiberglass, a common home insulator that grew popular after the dangers of asbestos became more widely known, is itself now associated with a range of health issues. Microscopic slivers of fiberglass can break loose during handling and be inhaled, irritating the lining of the respiratory tract and becoming lodged in lung tissue. This can cause a fibrous buildup that reduces lung capacity, or cause DNA mutations that can lead to lung cancer. In fact, cancer warnings appear on all fiberglass insulation sold in the United States.

Although wearing a respirator or dust mask can prevent inhalation of fibers during installation, all three principal U.S. manufacturers of fiberglass insulation now seal their batts in a perforated polyethylene or polypropylene sheeting so as to prevent airborne exposure. Nevertheless, for those suffering from aggravated respiratory problems, replacing fiberglass insulation with a more environmentally friendly alternative may be the best option. Luckily there are many such options available.

A favorite of environmental advocates is cellulose, which is made from recycled, shredded newspaper. In his book, The Solar House, author Dan Chiras calls cellulose “one of the most environmentally friendly insulation choices.” It is also highly efficient, readily available and economically priced, he says, and thus competes well with fiberglass.

Chiras also recommends cotton insulation, calling it “a natural product and safe from a human health standpoint,” while acknowledging that it is twice the price of fiberglass and “one of the most chemically intensive crops grown in the United States.” It contains no formaldehyde binders, however, a health and environmental plus, and usually contains a fire retardant, an important safety consideration.

Radiant barriers are another option, says the Fiberglass Information Network. Ideal for hot climates, they are made from metal foil and either kraft paper or bubble wrap. The Network also recommends insulation batts made from recycled #1 plastic, known as PET, the same material used to make some soda bottles and carpeting. Made by RTICA, based in Stony Creek, Ontario, the batts are installed just like fiberglass and make for an excellent fiberglass replacement choice.

But before ripping out that old fiberglass, it may be worth getting a professional to evaluate the integrity of your home’s ductwork. With properly sealed ducts, any stray fiberglass slivers inside your walls should not be able to get out. In the case of duct contamination, your best bet is to replace the entire system. Duct cleaning is also an option, but the U.S. Environmental Protection Agency does not recommend it. If you do decide to opt for cleaning, the National Air Duct Cleaners Association offers a list of companies that can do the work.

Critics also point to the fact that meat-based diets exacerbate world hunger. Harvard nutritionist Jean Mayer estimates that a 10 percent reduction in U.S. meat consumption would free up enough grain to feed 60 million people. Some 40 percent of the world’s grain harvest is fed to livestock, while nearly a billion people go hungry each day.

CONTACTS: Fiberglass Information Network, www.sustainableenterprises.com/fin; RTICA, (905) 643-8669, www.rtica.com, National Air Duct Cleaners Association, (202) 737-2926, www.nadca.com.

Dear EarthTalk: What is being done about arsenic contamination in drinking water? -- Erika Maxel, Cleveland, OH

Arsenic occurs naturally in our environment, and there are trace amounts of it in all living matter. In fact, arsenic is part of the Earth’s crust, and as a natural component of underground rock and soil it can work its way into our groundwater in amounts that pose little or no threat to human health.

However, arsenic is also a by-product of industrial activity, such as coal burning, waste burning, copper smelting, and mining for gold and other metals. It is also an agricultural byproduct as it is a component of some pesticides and feed additives. U.S. smokestack and agricultural industries release thousands of pounds of arsenic into the environment each year--and as a result arsenic can show up in public water supplies in amounts that do pose health threats.

According to a 1999 study by the National Academy of Sciences, excessive arsenic in drinking water can cause bladder, lung and skin cancer, and may cause kidney and liver cancer. The study also found that arsenic harms the central and peripheral nervous systems, as well as heart and blood vessels, and causes serious skin problems. It also may cause birth defects and reproductive problems.

The U.S. government regulates arsenic content in drinking water by setting a maximum contaminant level which, for many years, was 50 parts per billion. After further and more recent study, the U.S. Environmental Protection Agency (EPA) recommended in 2001 that the maximum level be lowered to just 10 parts per billion. Initially, the Bush administration rejected the recommendation, arguing that there was no scientific consensus to justify the $200 million it would cost to change the standard. But pressure from environmental and public health organizations convinced the White House to change course and adopt the stricter standard, which will take effect in 2006.

Although few if any municipal water systems in the U.S. exceed the present limit, it is estimated that many will have to install or upgrade treatment processes in order to meet the new stricter standard. Research by the Natural Resources Defense Council (NRDC) indicates that more than 34 million Americans drink tap water supplied by systems containing average levels of arsenic that pose unacceptable health risks.

Consumers can determine the arsenic levels, if any, in their drinking water by reading the Drinking Water Quality Report (also known as the Consumer Confidence Report) issued in July every year by each municipal water utility. Individuals can reduce their exposure to arsenic in drinking water by using a water filter certified by the National Sanitation Foundation (NSF). Consumers should also beware that bottled water is not necessarily any safer than tap water. According to NRDC, bottled water is often nothing more than tap water that may or may not have been filtered--so filtration is the only way to be sure that drinking water is arsenic-free.

CONTACTS: U.S. EPA Arsenic in Drinking Water page, www.epa.gov/safewater/arsenic.html; EPA Consumer Confidence Report page, www.epa.gov/safewater/ccr1.html; Natural Resources Defense Council, (212) 727-2700, www.nrdc.org; National Sanitation Foundation, (800) NSF-MARK, www.nsf.org.

Dear EarthTalk: What is the modern meat industry’s impact on the environment? -- Jeremy Smith, Bellefonte, PA

In E - The Environmental Magazine’s January/February 2002 cover story, “So You’re an Environmentalist…Why Are You Still Eating Meat?” author Jim Motavalli wrote, “Just about every aspect of meat production--from grazing-related loss of cropland and open space, to the inefficiencies of feeding vast quantities of water and grain to cattle in a hungry world, to pollution from ‘factory farms’--is an environmental disaster with wide and sometimes catastrophic consequences.”

Indeed, according to the Sierra Club, producing one pound of grain-fed beef requires about 16 pounds of wheat and--as staggering as it sounds--2,500 gallons of water. Furthermore, millions of acres of forest have been cleared worldwide to make room for the large areas of land needed for cattle grazing. In the United States, more than 260 million acres of forest have been cleared to grow crops to feed animals raised for meat, and an acre of trees disappears every eight seconds.

Tropical rainforests are also being cut to create grazing land for cattle. Fifty-five square feet of rainforest may be destroyed to produce just one quarter-pound burger. Since trees absorb carbon dioxide, the leading “greenhouse gas,” this significant loss of forest contributes to global warming as well.

Soil erosion is also mostly due to the meat industry which, according to the Worldwatch Institute, is directly responsible for 85 percent of all soil erosion in the U.S. because so much grain is needed to feed the animals. Livestock is fed more than 80 percent of the corn and 95 percent of the oats grown by American farmers. The world’s cattle alone consume a quantity of food equal to the caloric needs of 8.7 billion people--more than the entire human population on Earth.

Additionally, some believe that GE foods can be hazardous to human health when ingested. Ronnie Cummins of the Organic Consumers Association says that GE foods have been linked to many health problems, including blood disorders and food allergies. For instance, a few years ago Pioneer Hi-Bred International, in order to boost the protein content of its products, developed a soybean using a gene from a Brazil nut. Independent tests on the GE soybean revealed that people allergic to Brazil nuts could have severe allergic reactions to the modified soybeans.

A recent report prepared for the Senate Agricultural Committee concluded that animal waste is the largest contributor to pollution in 60 percent of the rivers and streams classified as “impaired” by the U.S. Environmental Protection Agency. The report states that food animals produce waste at a rate of roughly 68,000 pounds per second. Major waste pollutants that make their way into our waterways include nutrients like nitrogen and phosphorus that can cause massive fish kills, harmful bacteria and viruses, and toxic heavy metals, which are present in some commercial livestock feed.

Critics also point to the fact that meat-based diets exacerbate world hunger. Harvard nutritionist Jean Mayer estimates that a 10 percent reduction in U.S. meat consumption would free up enough grain to feed 60 million people. Some 40 percent of the world’s grain harvest is fed to livestock, while nearly a billion people go hungry each day.

While environmental groups recognize the benefits of vegetarianism as an alternative, few recommend it for everyone. Meat-loving environmentalists can look for small farms that feed livestock natural, organic diets, treat animals more humanely, and practice more sustainable land use.

CONTACTS: E Magazine, January/February 2002 issue, www.emagazine.com/view/?142; Sierra Club, (415) 977-5500, www.sierraclub.org/factoryfarms/ ; Worldwatch Institute, (202) 452-1999, www.worldwatch.org.

Dear EarthTalk: Are contact lens fluids safe for the environment and personal health? -- M. Luh, Storrs, CT

According to the Contact Lens Council, approximately 34 million Americans now wear contact lenses. Most people use various saline and disinfectant solutions for their lenses from big-name companies like Bausch & Lomb and Johnson & Johnson. These products are usually packaged in squeeze bottles that, according to Food and Drug Administration (FDA) regulations, are required to have preservatives.

But many preservatives can cause irritation and discomfort to the user. For example, thimerasol, a preservative commonly used in contact lens disinfectant solutions in the past, was found to be the culprit in severe allergies. One particularly harmful by-product of thimerasol, once it degrades or metabolizes, is ethyl mercury, which researchers now believe plays a role in the development of autism and a number of health problems.

Other preservatives like benzalkonium chloride have now replaced thimerasol in contact lens solutions. However, according to the Switzerland-based Perret Opticiens, there is still the possibility of such allergic reactions as redness, itching and discharge with the new generation of preservatives being used in conventional solutions.

A Danish study by Kolstad, Brandt and Rasmussen revealed that pregnant dry cleaning workers are twice as likely to have a miscarriage as pregnant women in other professions. And the University of California at Berkeley found that male dry cleaning workers have more sperm abnormalities and a significantly lower sperm count than men not employed by the industry.

Less toxic alternatives to perc are beginning to take hold. Comet Cleaners, which has 350 locations in 17 states and Mexico, replaced perc a decade ago with the more benign petroleum solvent, Exxon D-2000. Other cleaners have switched over to Chevron-Phillips’ EcoSolv, a similar hydrocarbon-based alternative. Meanwhile, more than 200 cleaners--including Chicago’s Greener Cleaner--employ “wet cleaning,” a non-toxic, non-polluting alternative that uses biodegradable soap and water.

There are other options. Clear Conscience now makes a line of contact lens solutions that are reportedly gentler for the environment and the wearer. Unlike conventional products, the company’s saline solution is dispensed by a safe nitrogen propellant, which means it contains no preservatives. Clear Conscience also offers an FDA-approved Multi-Purpose Solution that is benzalkonium chloride- and thimerasol-free. It can be used to disinfect, clean and store hard or soft contacts. WholeFoods Markets and other large natural goods stores stock Clear Conscience products, or they can be ordered online at the company’s website.

Meanwhile, Alcon, one of the largest providers of traditional lens solutions, has diversified its product line to include two preservative-free products, Unisol 4 and Pliagel, both which are available online at drugstore.com as well as at other large health products retailers.

CONTACTS: Contact Lens Council, (800) 884-4CLC, www.contactlenscouncil.org; Clear Conscience, (800) 595-9592, www.clearconscience.com; Perret Opticiens, www.perret-optic.ch/index_gb.htm; Alcon Labs, (800) 757-9195, www.alconlabs.com; drugstore.com.

Dear EarthTalk: Would removing the bald eagle from endangered species protection, as proposed by some environmental groups and the Bush administration, be considered an environmental victory? -- William Young, Chappaqua, NY

Just 30 years ago, the once-abundant bald eagle--America’s national symbol--was in danger of extinction in its primary habitat across the lower 48 states. Hunting, sprawl and poisoning from the agricultural pesticide DDT had conspired against this majestic raptor, despite safeguards in place under the Bald Eagle Protection Act of 1940. Fewer than 500 breeding pairs remained and the outlook was grim.

But with the banning of DDT in 1972 and the passage of the Endangered Species Act (ESA) in 1973, eagle populations began to rebound. By July 1995, the species had recovered to 5,700 pairs, and was upgraded from “endangered” to “threatened” status under the ESA. Today, biologists estimate that more than 7,600 breeding pairs inhabit the lower 48 states, and the Bush administration has proposed de-listing the species once and for all in 2005.

Conservation efforts have indeed made the eagle’s recovery possible, but nonetheless even the environmental community is split on whether or not de-listing the bird is a good idea. Some say that the eagle’s recovery has exceeded expectations and that de-listing would be the culmination and celebration of a great American conservation success story--proof that the ESA works.

“The species’ numbers have steadily increased over the past three decades, so much so that in some areas, such as the Chesapeake Bay region, there are hundreds more eagles today than there were prior to the DDT era,” says endangered species law expert Michael Bean of Environmental Defense, a non-profit group that was originally instrumental in the banning of DDT. Last spring, Environmental Defense lobbied the White House to put forth the most recent eagle de-listing proposal.

Additionally, some believe that GE foods can be hazardous to human health when ingested. Ronnie Cummins of the Organic Consumers Association says that GE foods have been linked to many health problems, including blood disorders and food allergies. For instance, a few years ago Pioneer Hi-Bred International, in order to boost the protein content of its products, developed a soybean using a gene from a Brazil nut. Independent tests on the GE soybean revealed that people allergic to Brazil nuts could have severe allergic reactions to the modified soybeans.

But other eagle advocates worry that key protections would no longer be in effect if de-listing were to take place. Kieran Suckling, executive director of the Center for Biological Diversity, says that earlier efforts by the Clinton White House to de-list the eagle stalled after federal biologists warned that contaminants in the environment and habitat loss were still preventing some eagle populations from achieving optimum reproduction rates. And budget cuts in the interim have meant that no additional eagle population monitoring has taken place. Without any new data to justify de-listing, Suckling and others consider taking endangered species protection away from the eagle at this point to be not only premature but also illegal.

Federal officials have put forth similar proposals to take the gray wolf and the grizzly bear off the threatened list as well. These great conservation success stories underscore how important the ESA has been. But as new, larger threats to wildlife--including habitat loss and global warming--loom, many are left wondering if we’re celebrating victory in the war against species loss a little too soon.

CONTACTS: Environmental Defense, (212) 505-2100, www.environmentaldefense.org; Center for Biological Diversity, (520) 623-5252, www.biologicaldiversity.org/swcbd/; U.S. Fish & Wildlife Service Endangered Species Program, http://endangered.fws.gov/.

Dear EarthTalk: I’ve heard that the solvents commonly used in commercial dry cleaning are unhealthy and unsafe for the environment. Is this true? -- Earl Eckstrom, Portland, OR

Studies show that perchloroethylene--the solvent used by the vast majority of dry cleaning establishments--is both hazardous to human health and injurious to the environment. For one, “perc,” as the solvent is commonly known in the industry, can have negative effects on the central nervous system. According to the National Institute of Environmental Health Sciences, short-term exposure to perc can lead to headaches, nausea, dizziness and memory problems.

The environmental organization Greenpeace found that perc breaks down into toxic byproducts like phosgene, vinyl chloride, carbon tetrachloride and trichloroacetic acid (TCA). Dr. Gina Solomon, a senior scientist at the Natural Resources Defense Council, says, “Phosgene is an extremely hazardous gas which evaporates and in closed spaces is potentially lethal. Vinyl chloride is a proven carcinogen and carbon tetrachloride is a known liver toxin.” And TCA has been linked to the extensive damage done to trees in the Black Forest in Germany, where it was used as an herbicide in the 1950s and 1960s.

While the use of rinse-aid to combat dishwasher streaking is no environmental crime, those concerned about the consumption of resources might think twice about the need for it. Mainstream rinse-aid, like dishwasher soap itself, contains phosphates in its cleaning agents. Wastewater containing phosphates which escapes sewage treatment can cause excessive algae growth in waterways which in turn pollutes drinking water and leads to marine “dead zones”--underwater environments deprived of oxygen and thus unable to support life. Consumers should keep in mind that dishwasher soaps, as well as laundry detergent and many other household items, also contain phosphates that can cause problems if not disposed of properly.

A Danish study by Kolstad, Brandt and Rasmussen revealed that pregnant dry cleaning workers are twice as likely to have a miscarriage as pregnant women in other professions. And the University of California at Berkeley found that male dry cleaning workers have more sperm abnormalities and a significantly lower sperm count than men not employed by the industry.

Less toxic alternatives to perc are beginning to take hold. Comet Cleaners, which has 350 locations in 17 states and Mexico, replaced perc a decade ago with the more benign petroleum solvent, Exxon D-2000. Other cleaners have switched over to Chevron-Phillips’ EcoSolv, a similar hydrocarbon-based alternative. Meanwhile, more than 200 cleaners--including Chicago’s Greener Cleaner--employ “wet cleaning,” a non-toxic, non-polluting alternative that uses biodegradable soap and water.

Perhaps the most promising non-toxic perc alternative is produced by GreenEarth Cleaning, which has patented its silicone-based dry cleaning solvent called Cyclic Silioxane. This product poses no threat to the environment or human health and simply degrades to sand, water and carbon dioxide. General Electric and Proctor & Gamble have formed a joint venture with GreenEarth to help dry cleaners worldwide switch over to this more benign alternative. At greenearthcleaning.com, consumers can search an international database to find dry cleaners in their area that are using the new solvent.

While the U.S. Environmental Protection Agency (EPA) regulates the use of perc under the Toxic Substances Control Act, the Clean Water Act and the Safe Drinking Water Act, states have been reticent to adopt phase-outs. The dry cleaning industry has mounted a strong lobby in favor of keeping perc legal, but consumer opposition is building, especially as more non-toxic alternatives are becoming available.

CONTACTS: Natural Resources Defense Council, (212) 727-2700, www.nrdc.org; Comet Cleaners, (817) 461-3555, www.cometcleaners.com; Green Earth Cleaning, (816) 926-0895, www.greenearthcleaning.com; EPA Perc Fact Sheet, www.epa.gov/opptintr/chemfact/f_perchl.txt.