was taken and sent to a commercial veterinary
rus in the fat of dead birds remains the most relia-
diagnostic lab to determine changes in specific
ble indicator of exposure, but its instability
diminishes its value to determine exposure in liv-
blood parameters. The blood factors that showed
ing birds.
the greatest response to WP included blood urea
Multiple daily exposures to P4 over 4 days did
not alter mortality above what would be expected
dehydrogenase, aspartate aminotransferase/ala-
by the acute levels of dosing solutions. There was
nine aminotransferase ratio, potassium, and glu-
a significant dose response in weight loss during
cose. Hematocrit, hemoglobin, chloride, sodium,
treatment, probably attributable to malaise or
and phosphorus also differed significantly due to
inappetence, but this was transitory, and birds
treatment. These blood factors reflect the liver
recovered their pre-treatment weights within 7
and renal damage identified by histopathological
days after exposure.
examination and hemolysis observed in pen
studies. Additional analyses of other blood sam-
ples taken in laboratory and field situations are
Sparling, D.W., R. Grove, E. Hill, M. Gustafson,
and P. Klein (1995) White phosphorus toxicity
near completion and seem to support the above
and bioindicators of exposure in waterfowl and
findings. At this early date, we suggest that
raptors. In Interagency expanded site investigation:
reduced hematocrit and hemoglobin levels could
Evaluation of white phosphorus contamination and
be effective, reliable, and relatively simple screen-
potential treatability at Eagle River Flats, Alaska
ing techniques to identify birds that may have
(C.H. Racine and D. Cate, Ed.). CRREL Contract
been exposed to white phosphorus.
Report to U.S. Army, Alaska, Directorate of Public
Works, FY94 Final Report, p. 201234.
Preliminary studies on reproductive effects of
During 1994 researchers at the National Bio-
WP in female mallards
logical Service Patuxent Environmental Science
White phosphorus is a strong reducing agent,
Center conducted studies on seven tasks associ-
is lipid soluble, and appears to affect many physi-
ated with risk assessment and monitoring of
ological processes in mallards. Therefore, it has
white phosphorus (WP) in Eagle River Flats, Fort
the potential of reducing reproduction and col-
Richardson, Alaska. These tasks included: 1)
lecting in egg yolks, where it could affect devel-
identification of biomarkers of WP in waterfowl;
oping embryos. A pilot study was conducted to
2) preliminary studies on reproductive effects of
determine if repeated handling of adult female
WP in female mallards; 3) timing of uptake and
mallards alone would impair reproduction or egg
loss of WP and the onset of pathology in mallards;
laying ability and to find effective dose levels pri-
4) derivation of LD50 and associated statistics for
or to a more complete reproductive study. Four to
five female mallards were gavaged with pellet-
adult female mallards; 5) analysis of acute tox-
ized WP at either 2.6 or 1.3 mg/kg body weight
icity with pelletized WP; 6) examination of sec-
ondary toxicity in kestrels fed dosed poultry
daily for 5 days. Other groups were either given a
chicks; and 7) use of semi-permeable membranes
placebo of distilled water or left alone except for
(SPMAs) in monitoring WP in water and sedi-
daily egg collection (control). The placebo and
ments.
control groups did not differ in number of eggs
laid, fertility, or hatching success. Thus, we deter-
Identification of biomarkers for
mined that daily handling did not appreciably
white phosphorus exposure in birds
alter reproduction in these birds. Two of the five
females given 2.6 mg WP/kg body weight died
White phosphorus residues can only be mea-
within the first 5 days of treatment; another
sured in living tissues for a few days after expo-
became lethargic and showed obvious signs of
sure. Moreover, sublethal doses of white phos-
distress. All three surviving birds stopped laying
phorus can cause chronic or long-lasting effects.
eggs after two doses. One of these birds came
Therefore, identification of other physiological
back into sporadic lay 11 days after the last dose
effects of exposure or bioindicators are essential
for reliable assessment of risk to waterfowl and
but did not produce fertile eggs. Four young
other species inhabiting areas contaminated with
hatched from these hens but from early eggs that
WP. In an initial study to identify potential bio-
probably escaped exposure to white phosphorus.
markers, mallards were dosed either once or
One embryo had severe teratogenic deformities.
twice with WP dissolved in oil. Before dosing and
At 1.3 mg/kg, one hen stopped laying after two
3 days post each dose, a 5-mL sample of blood
doses and the other four birds laid erratically so
64
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