Juice wars, turtle tumors and greener houses. (Ask E).

What are the pros and cons of juice pasteurization? --Sabrina Coolidge, Portland, OR

Some consumers are skeptical of pasteurization because they are concerned that the heat treatment will compromise the nutritional value of juice. According to Odwalla, a natural juice company, there is an approximate 30 percent nutrient loss during pasteurization. But the U.S. Food and Drug Administration (FDA) maintains that untreated juices pose a health risk for consumers. The FDA says approximately 98 percent of juice on the market has been pasteurized, which kills harmful bacteria such as E. coli O157:H7 and Salmonella.

In 1996, California, Colorado and Washington experienced numerous outbreaks of E. coli infections caused by a batch of un-pasteurized Odwalla apple juice. The incident resulted in the death of one toddler, 14 life-threatening kidney illnesses and 30 lesser injuries. Odwalla now uses a process called "flash pasteurization" which the company says kills only harmful pathogens, and retains more enzymes and vitamins than conventional techniques. Although the FDA does not require pasteurization, it does mandate consumer warnings on fresh juices. CONTACT: FDA Center for Food Safety and Applied Nutrition, [phone], www.cfsan.fda .gov; Odwalla, (800) ODWALLA, www.odwalla.com.--A.D.

I heard that sea turtles are being killed by cancerous tumors at an alarming rate. Why is this happening? --Brendon Hunt, New York, NY

Sea turtles have long confronted the challenges of hunting, intensive fishing practices and habitat degradation. In the last 20 years, marine turtles have also been attacked by a deadly tumor called Fibropapilloma (FB). FB tumors are bulbous growths that primarily affect the turtles' skin, but can also appear in their mouths, on their eyes and internal organs. In the 1980s, the disease began to reach epidemic proportions in shallow, near-shore waters with low circulation off Hawaii, Florida and Barbados. George H. Balazs of the National Marine Fisheries Service says that while progress is being made to understand FB, there are no definitive causes yet.

The tumors have mostly been found on adult green turtles, but have recently showed up on the loggerhead and olive ridley species as well. Sue Schaf of Marathon, Florida's Turtle Hospital says, "We were seeing 50 percent of green [turtles] with tumors, but now it is closer to 70 percent and getting worse. We are also observing more cases of internal tumors." CONTACT: Turtle Hospital, [phone], www.turtlehospital.org.

What are my options for building a house with an ecologically sensitive design? --Shaun Jackson, Olympia, WA

If you are worried about the environmental impact of building a new house, the good news is there are a number of materials and techniques available for "greener design" Some environmentally sensitive features--such as solar hot water systems, radiant floors and extra thick windowpanes--can push the cost of building to double that of a conventional house. But they don't have to, argues Donald Watson, a Connecticut-based architect. "If you design creatively, you can build greener at comparable, or sometimes even reduced, costs" Even if the initial costs are greater, the long-term investment in solid construction and efficiency should pay off.

If you are on a modest budget and flexible in your needs, you may want to choose a pre-existing blueprint (such as Watson's $99 "Ecology House" plan), many of which offer some latitude for customization. But if you have an exact idea of what you want, and you are willing to pay the price, a good green architect can help you build your dream house. Those interested in going this route may wish to contact Austin, Texas' Center for Maximum Potential Building Systems (CMPBS). Two excellent general resources are the Rocky Mountain Institute's A Primer on Sustainable Building and the Green Building Directory. CONTACT: CMPBS, [phone], www.cmpbs.org; Green Building Directory, www.greenbuilder.com; Rocky Mountain Institute, [phone], www.rmi.org; Donald Watson, [phone].

Send your questions about environmental issues, from the personal to the political, to Ask E, P.O. Box 5098, Westport, CT 06881, or by e-mail to [e-mail]. Please keep your questions brief, and type them double-spaced. Include your full name, address and a daytime phone number.