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Your Environment. Your Health.

Why are the Frogs Malformed? -- Parasites, Pesticides and/or UV? Is There a Broader Problem for Human Health?

National Institute of Environmental Health Sciences (NIEHS)

News Release

Archive - New Contact Information

For more information about this archival news release, please contact Christine Flowers, Director, Office of Communications & Public Liaison at (919) 541-3665.
Tuesday, November 18, 1997, 12:00 p.m. EDT
Contact: Bill Grigg, NIEHS
(301) 402-3378

In Minnesota, Wisconsin, New York, Vermont and parts of Canada:

A workshop on Strategies for Assessing the Implications of Malformed Frogs for Environmental Health will be held Dec. 4-5 at the Conference Center at the National Institute of Environmental Health Sciences, 111 Alexander drive, Research Triangle Park, NC. Sessions begin at 8:30 a.m.

Alerted by a group of schoolchildren who spotted malformed and missing limbs in a Minnesota farm pond in 1993, and posted their observations on the Internet, biologists surveyed the situation and three years ago confirmed malformations in large numbers of frogs in that state. Then, deformed frogs were reported in Wisconsin, New York, Vermont and several others states as well as parts of Ontario and Quebec. The National Reporting Center for Amphibian Malformities has an Internet site at ttp:// that lists additional areas and provides some of the key news reports on the phenomenon.

At least three theories have been put forward for the deformities: 1) chemicals, such as pesticides from nearby agricultural fields, 2) increased ultraviolet radiation due to ozone depletion, and 3) parasitic invasions. There may be more than one factor at work.

Recently, the Minnesota Pollution Control Agency and NIEHS reported preliminary research showing that water from several ponds with deformed frogs and nearby wells also caused a high incidence of malformed embryos of Xenopus laevis frogs, which are used in the Frog Embryo Teratogenesis Assay: Xenopus, known as FETAX. As a precaution, MPCA has offered free bottled water to some residents. Judy Helgen of MPCA and James Burkhart, NIEHS, will discuss their continuing work early Thursday afternoon Dec. 4, followed by a discussion of the use of "sentinel species" for ecological and human health assessments by Hank Gardner of the US Army Center for Environmental Health Research.

Gerald Ankley of the Environmental Protection Agency, who has pursued increased UV radiation from the depletion of the ozone layer, will discuss his findings Thursday morning at 11:20.

The workshop is open to the press, but space is limited. Media representatives should provide their names, broadcasting station or publication, phone and fax-and any special needs-to Ruth McFarland, 919/541-3345. (Or FAX to 919/541-4395.) Mrs. McFarland can also fax to the media an agenda listing speakers. NIEHS is 25 minutes by car, van or cab from Raleigh-Durham airport. Flights from Washington's National Airport to RDU take less than an hour via Midway and USAir.

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