|
follow
this link to download press release as pdf file
SACRAMENTO -- The California Environmental Protection Agency's
Office of Environmental Health Hazard Assessment (OEHHA) is seeking
public comments on a draft
fish advisory concerning elevated levels of mercury in certain fish
from five reservoirs and portions of the Bear and South Yuba rivers
and Deer Creek in Nevada, Placer and Yuba counties.
Once finalized, the fish advisory will be the first ever issued
by the State of California for water bodies in the Sierra Nevada.
"We are using 21st-century science to evaluate potential health
threats from eating fish containing mercury that was released into
Sierra streams as far back as the Gold Rush," OEHHA Director
Dr. Joan Denton said. "In most cases, limited amounts of fish
can be eaten safely, but we recommend that people - especially females
of childbearing age and children - carefully monitor how much they
eat."
A draft report containing the proposed advisory and OEHHA's evaluation
of potential health threats posed by mercury in the fish is available
for viewing and downloading on OEHHA's Web site at www.oehha.ca.gov.
OEHHA will hold a public workshop in Grass Valley at 2 p.m. on February
27, 2003, to discuss and receive public comments on the draft evaluation
and proposed advisory. The workshop will be held at the Nevada Irrigation
District Conference Room, 1036 West Main Street. Written comments
can be sent until February 27 to OEHHA's Pesticide and Environmental
Toxicology Section, P.O. Box 4010, Sacramento, CA 95812-0410.
The draft advisory contains proposed guidelines for consumption
of bass, channel catfish and other fish species from Camp Far West
Reservoir, Lake Combie, Lake Englebright, Rollins Reservoir, Scotts
Flat Reservoir and portions of the South Yuba River, Deer Creek
and Bear River. One set of proposals is for females of childbearing
age and children age 17 and younger, who are particularly sensitive
to methylmercury (the most prevalent form of mercury in fish). A
second set of proposals is for adult males and females beyond their
childbearing years.
The proposed guidelines call for females of childbearing age and
children to refrain from eating all bass from Camp Far West Reservoir;
limit their consumption of bass and channel catfish from the other
water bodies to 1 to 2 meals per month, depending on where the fish
were caught; and limit their consumption of trout from Deer Creek
to 2 meals per month. The proposed guidelines also call for females
beyond childbearing years and adult males to limit their consumption
of bass and channel catfish to 2 to 4 meals per month, depending
on where the fish were caught; and limit consumption of Deer Creek
trout to 4 meals per month.
OEHHA's evaluation and draft advisory are based on fish samples
from the five reservoirs and 14 stream sites in the watersheds taken
by the U.S. Geological Survey (USGS) in 1999. OEHHA completed an
initial analysis of the sampling results in 2000 and assisted local
health offices in Nevada, Placer and Yuba counties in developing
interim health advisories that recommend adults and children limit
their consumption of bass species to 1 meal per month, and channel
catfish and various other species to 1 meal per week. The OEHHA
draft fish advisory is based on a more extensive evaluation of the
USGS data and will replace the interim county advisories when it
is finalized.
Mercury in fish from these watersheds is a legacy of gold mining
dating from the Gold Rush. Miners used inorganic mercury to extract
gold from mined materials and discharged the waste into streams,
where mercury accumulated in the sediment. Bacteria converted the
inorganic mercury to the more toxic methylmercury, which fish take
in from their diet. Methylmercury can accumulate in fish to concentrations
many thousands of times greater than mercury levels in the surrounding
water.
Women can pass methylmercury on to their fetuses through the placenta,
and to infants through breast milk. Excessive exposure to methylmercury
may affect the nervous system in children, leading to subtle decreases
in learning ability, language skills, attention and/or memory. These
effects may occur through adolescence as the nervous system continues
to develop. In adults, the most subtle symptoms clearly associated
with methylmercury toxicity are numbness or tingling sensations
in the hands and feet or around the mouth. Other symptoms at higher
levels of exposure could include loss of coordination and vision
problems.
The Office of Environmental Health Hazard Assessment is one
of six entities within the California Environmental Protection Agency.
OEHHA's mission is to protect and enhance public health and the
environment by objective scientific evaluation of risks posed by
hazardous substances.
|
Conditions of Use/Privacy