7092

• UCREFRP Catalog Number: 7092
• Author: Eisler, R.
• Title: Arsenic Hazards to Fish, Wildlife, and Invertebrates
• USFW Year: 1988.
• USFW - Doc Type: A Synoptic Review.
• Copyright Material: NO

temperatures. Uptake was significantly higher at 19 o/oo salinity than at 38
o/oo, but loss rate was about the same at both salinities. Radioarsenic loss
followed a biphasic pattern; biological half-life was 3 and 32 days for the
fast and slow compartments, respectively; secretion of the byssal thread
played a key role in elimination (Unlu and Fowler 1979). Factors known to
modify rates of arsenic accumulation and retention in a marine shrimp (Lysmata
seticaudata) include water temperature and salinity, arsenic concentration,
age, and especially frequency of molting (Fowler and Unlu 1978).
Bioconcentration factors (BCF) experimentally determined for arsenic in
aquatic org?2isms are, except for algae, relatively low. The BCF values for
inorganic As in most aquatic invertebrates and fish exposed+5for 21 to 30
days, did not exceed 17X; the maximum was 6X for As , and 9X for
organoarsenicals (EPA 1980, 1985). Significantly higher BCF values were
recorded in other aquatic organisms (NRCC 1978), but they were based on mean
arsenic concentrations in natural waters that seemed artificially high. A BCF
of 35H was reported for the American oyster (Crassostrea virginica) held in 5
ug As /1 for 112 days (Zaroogian and Hoffman 1982). There was no relation
between oyster body burdens of arsenic and exposure concentrations; however,
diet seemed to contribute more to arsenic uptake than did seawater
concentrations (Zaroogian and Hoffman 1982). An arsenic-tolerant strain of
freshwater alga (Chlorella vulgarus) frorp5 an arsenic-polluted environment
sh?Wed increasing growth up to 2,000 mg As /1, and could survive at 10,000 mg
As /1 (Maeda et al. 1985). Accumulations up to 50,000 mg As/kg dry weight
were recorded (Maeda et al. 1985)--suggesting a need for additional research
on the extent of this phenomenon and its implications on food web dynamics.
Some investigators have suggested that arsenic in the form of arsenite is
preferentially utilized by marine algae and bacteria (Johnson 1972; Bottino et
al. 1978; Johnson and Burke 1978). Arsenate reduction to arsenite in seawater
depends on phosphorus in solution and available algal biomass (John?gn a+g
Burke 1978). During algal gowth, as phosphate is depleted and the + /As
ratio drops, the rate of As reduction incre?tees. The resultant As , after
an initial peak, is rapidly oxidized to As , indicating J?e possibility of
biological catalysis of oxidation As well as mediation of As reduction. It
is generally accepte15 that As+ is more toxic than arsenates to higher
organisms; however, As hadA more profound effect on growth and morphology
of marine algae than did As Possj?ly marine algae erect 45barrier against
the absorption of As , but not of As Within the cell, As can then be
reduced to the possibly more toxic As For example, the culture of two
species of marine algae (Tetraselmis 09, Hym?Qomonas carterae) in media
containing various concentrations of As or As showed that arsenic effects
varied with oxidation state, concentration, and light intensity. Arsenate was
incorporated and later partly released by b??h species. Differences between
rates of uptake and release suggest that As undergoes chemical changes after
incorporation into algal cells (Bottino et al. 1978). When bacterial cultures
fry the Sargasso Sea and from marine waters of Rhode jkland were grown 12
As -enriched media, the bacteria reduced all available As and utilized As
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