Fish and Wildlife
monitors spatial and temporal trends in contaminant exposure in Puget
Sound fish and macro-invertebrates and the effects of contaminant exposure
on the health of these resources. Currently, we monitor five environmental
provide information on the contaminant–related environmental conditions
of fish and macro-invertebrates in the Puget Sound ecosystem.
- Contaminant levels
in tissue and bile2 are
measures of exposure to chemical contamination and serve as indicators
of environmental quality --- the higher the contaminant exposure,
the lower the environmental quality.
- Liver disease in adult
English sole, measured as the prevalence of toxicopathic3 liver lesions4,
can be an indicator of the fishes’ exposure to PAH5 contaminated sediments. Furthermore, the degree of liver
disease serves as a general indicator of fish health because reproductive
impairment has been observed in fish at sampling sites with elevated
occurrences of liver lesions.
- Endocrine6 disruption in male fish is measured by sampling their
blood for the presence of vitellogenin, a protein associated with
egg development. Vitellogenin is not normally present in males and
its presence indicates potential disruption of the reproductive system
because of exposure to contaminants that mimic estrogen.7
- Spawning success, measured by microscopic examination of reproductive organs, is used
to estimate percent of fish that recently spawned.
- Fish abundance is assessed to provide an estimate of the health of groundfish populations.
The Fish Component staff assists other marine fish staff to collect
Since 1989, Fish and Wildlife has monitored temporal trends in contaminant
levels and prevalence of liver disease in English sole at fixed sampling
locations throughout Puget Sound. As of 1999, we started to monitor
temporal trends in contaminant exposure in Pacific herring. Historically,
we monitored spatial patterns of contaminant exposure in a limited number
of species but now we have enhanced our monitoring design to better
define spatial patterns for biota from selected areas of Puget Sound.
Currently, information on our environmental indicators are collected
in three different types of studies.
- Baseline Assessment
Studies are used to examine temporal trends in contaminant
exposure in fish and macro-invertebrates and the prevalence of liver
disease in English sole from fixed sampling stations. The number and
location of sampling stations and sampling frequency is determined
by the life history of the species that is being monitored. Fewer
sampling locations are needed to assess species with broad movement
patterns that those species with restricted movement patterns. Short-lived
species can be monitored annually to document temporal trends whereas
long-lived species whose contaminant levels may reflect historic rather
than current exposure to contamination should be monitored less frequently
or not used for assessing temporal trends.
- Focus Studies are used to characterize the spatial patterns (i.e. areal extent)
of contaminant exposure for specific geographic location. These studies
also provide information on health of the biota (e.g. environmental
indicators that measure liver disease in English sole or endocrine
disruption in rockfish) in selected embayments of Puget Sound where
Baseline Assessment Studies indicate a contaminant problem.
- Pilot Studies are used to gather data to test assumptions of proposed Baseline Assessment
Studies and Focus Studies. For example, before starting a Baseline
Assessment Study, it may be necessary to determine if contaminants
accumulate in proposed target species or if factors such as the sex
or age of the fish affect contaminant exposure. Pilot studies are
only needed if the required data are not available in the literature.
Typically pilot studies for contaminant studies compare individuals
from a highly contaminated location (worst case) with an uncontaminated
location (best case).
In addition to documenting
spatial and temporal trends, chemical contaminant data are used to determine
whether Puget Sound seafood is safe for human consumption. Fish Component
data have been used by managers to issue a health
advisory (Sinclair Inlet), to help develop a model for sediment
quality standards that protect human health, and to provide data for
risk assessments at various Puget Sound locations. The Department of
Health (DOH) determines what concentration of contaminants in fish are
unsafe for human consumption based on their knowledge of the toxicity
of the contaminant, estimates of fish consumption, and duration of exposure.
For a given location, Fish and Wildlife assists the DOH by defining
the concentration of contaminants that are found in fish over a range
of sizes and ages.
measurement that provides an estimate of the effects of a known factor
(toxin, pollutant, environmental management program, etc.) on the state
or condition of the environment.
- Bile plays an important role in the intestinal absorption
of fats. It is a greenish-yellow fluid secreted by the liver and contains
cholesterol, bile salts and waste products such as bilirubin. Bile salts
aid in the digestion of fats. Bile passes out of the liver via the bile
duct where it is stored in the gallbladder and released in response to
a fat-containing meal.
- Noninfectious pathological conditions or lesions
in the liver and kidney which appear to have a positive relationship with
- An injury or other change in an organ or tissue
of the body tending to result in impairment or loss of function
- A class of chemicals typically formed by burning
and common in the environment. PAHs are also common to petroleum products
and oil. Although most of these compounds are harmless or mildly toxic,
some are carcinogenic.
- Pertains to internal secretions, hormonal
- A generic term for oestrus producing steroid compounds,
the female sex hormones.