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Dear water/fish techies,
Further chatter on the matter: bioavailable lead
from lost fishing sinkers in extremely low hardness salmonid habitat with
ESA listings. I have posted once before on the matter, received some good
advice from two forums, and even more good advice e-mailed directly to me
rather than posted on the forum. In the interest of furthering forum
diversity I will try to relate a little more to ponder.
Any advice, critique, info greatly appreciated.
I'm sure I'm overlooking a lot here.
Our waters drain over a geology that does not
leachout very many minerals or metals in spite of the copious rainfall in
western Oregon, hardness is
9 to 20 as CaCO3, pH 6 to 7 (usually) but rain is more acidic, summer
elevated temps and low DO
for fish. Grab samples (approx 24) gave about 3/4 as nondetects at d 1ppb.
The rest of the tests showed various dissolved lead 1.5 to 8 ppb with high
being 22ppb. No EPA 'Ultra clean QA/QC,but
much care was taken; and low risk waters were consistent as control, with
high risk waters showing
detects. Very low budget as yet... so am awaiting funding for higher
QA/QC... good luck huh?
We took a sample of upper watershed water (non-fished area) split it, took
a sinker out of the high risk area and suspended it carefully overnight in
one of the splits.... next day it tested out at 86ppb
compared to other at non-detect.
Huge numbers of lost sinkers exist on bedrock substrate that is abrading
sinkers. There is low flow in the critical warm months. EPA criteria is less
than 1/4ppb for this water for chronic exposure of biota. I know that these
are very dilute numbers,but my main concerns arise from research in chronic
low-dose behavioral effects of lead and methyl mercury
(Weber,Spieler,Hodson,Strickler-Shaw, Newland,Spry, Wiener, Sandheinsich,
and many more) and, Ruby et al. for estrogenic effects at what appear to be
environmentally significant levels to what we are seeing here. See:
Sublethal Lead Affects Pituitary Function of Rainbow Trout During Exogenous
Vitellogenesis S.M.Ruby, R.Hull,P.Anderson Arch.Envir.Contam Toxicol. 38,
46-51 (2000). See: Aminolevulinic Acid Dehydratase Activity of Fish Blood
as
an indicator of a Harmful Exposure to Lead Peter V. Hodson J. Fish.Res,
Board Can. 33:268-271.
Highly recommend: Aquatic Toxicology:Molecular, Biochemical and Cellular
Perspectives (Behavioral Mechanisms of Metal Toxicity in Fishes Dan Weber,
Richard Spieler) Ed. Donald C.Malins and Gary K. Ostrander Lewis Publishers
1994.
also: Enhanced Bioaccumulation of mercury, cadmium and lead in
low-alkalinity waters: An emerging regional environmental problem. Wiener,
J.G.;Stokes, P.M. Environ. Toxicol.Chem '90 vol. 9, no7, pp821-823.
Also, some of my main concern is not directly for the ESA species of
interest but for sensitive species that support the salmon. Some of our
fish
runs are showing signs of being food-limited at less than 1% of their
historic population levels. If, some portion of these runs become, in
effect, slightly dumber from sublethal, even subclinical levels of
bioavailable lead, they may have subtle behavioral impairment and have food
acquisition and predator avoidance problems at or near ocean -entry. we
don't have a metallothionein-inducing environment here that would probably
exist in say a mine effluent situation. There is concern for immunologic
effects in freshwater that could predispose to higher toxicologic infuence
of estuary pollutants. Agencies are dragging their butts... but the
government is spending many millions on work for non-ecotoxicologic salmon
diversity habitat restoration here...BUT, a totally inadequate WQ
assessment... sheesh! How
totally stupid...... So got any suggestions?
Ray Kinney
Siuslaw Soil and Water Conservation District
Dir. for water Quality
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