Alright, so walk me through the science of what we have here and what step of the process
we're at.
Okay, so we're at nearly the beginning, we're kind of at the midway point here, so typically
what we do is we have, usually we have the spears collect the fish for us, and we pay
usually $10 fish or so, and then we try to get at least 12 per lake where we're aiming,
and so that doesn't always happen, sometimes we collect the fish through population assessments,
and that's the way we got these, and these came from Michigan, from our sister agency,
KBSC, and so we're assessing, right now we're assessing the mercury content of the fish,
as well as the PFOS content of the fish, and I say mercury, but it's actually methyl mercury,
there's a big difference there, a lot of people, whenever you speak on that, they think of
the inorganic metal, and really we're dealing with the organic metal, which is a mercury
that has been methylated by typically anaerobic bacteria in say a marshland or a bog, so the
factors that contribute to that are your levels of sulfate, your pH contributes, and as well
as the dissolved oxygen, so as anaerobic bacteria work on this stuff, a lake with lower dissolved
oxygen, acidity, higher acidity, and then potentially higher sulfates, you'll see an increase in
the methyl mercury in those fish population. So it's important for you to study different
lakes because not even if they're next to each other, lakes may be different, right? Yes, that's
exactly right, and we're also monitoring trends over time, so this program has been enacted since
I want to say 1996 or so, and so it's been going on for nearly 30 years at this point, and what have
you seen over that time? Actually we've seen the trends are steady, they follow what you would
expect, you know, larger fish by accumulation, they tend to have more methyl mercury content,
right now the focus is actually towards PFOS, we're trying to detect hot spots, and so
with the fish you're not only are you making a food consumption advisory to let people know
if the fish are safe to eat within that lake, but also we are at the same time looking at the
quality of water because if your water is contaminated, your fish will be contaminated as well.
So what are the main concerns with methyl mercury? Obviously the consumption is the issue.
So your main concerns are it is a neurotoxin, or neurotoxin, so with methyl mercury it is,
all right, so methyl mercury is a neurotoxin, it is very toxic to our special populations to
women who may become pregnant, women who are pregnant, children, infants, newborns,
anything that has a developing brain is highly susceptible to methyl mercury toxicity.
And are people more aware of these? I mean obviously we've been doing this study a long time,
are people becoming more aware that they should take that seriously? More aware, we need, all right,
so more aware, they are aware, but as far as like the intricate details of it, I would say no,
we need to do more on that part. Like I said earlier, a lot of people believe it's like
liquid metal mercury, but no, here we're dealing with a organic form of mercury. In fact,
a lot of metals, if a metal is safe, take 10 for example, if you stick a methyl group,
a couple of methyl groups on 10, that metal goes from a safe metal to a white toxic metal.
So organic metals are typically something to always be concerned about.
And mercury is found everywhere, straightening.
Mercury is a natural occurring compound, when Marcus was speaking on earlier, how there is
atmospheric deposition of mercury, that's just something that happens naturally,
from combustion of fossil fuels, combustion of anything that's going on in the industry,
goes up into the air, and then it slowly will particulate out, and then there's a,
they have this model. There's people put this down to a math, and then, and so usually where
there's a higher concentration of industry, you can see more mercury deposition. In the past,
whenever, you know, the United States was in its, you know, industrial age, like we were making
metal manufacturing back here, that's what, that's when the levels were higher. They're looking at
what does that bay called out of Duluth, St. Louis, St. Louis River estuary. Yeah, so they're
monitoring that and keeping track of those levels, because that's a lot of industry in that area.
So we saw one of the fish where we saw a lot of, you know, the other fish popping out of it.
Right. Just talk about that food prop.
Okay, so the bioaccumulation? Yeah. So, you know, once the mercury is deposited into the soil,
the water, it then becomes part of the, you know, the natural cycle of things that it is taken up,
you know, you imagine like a little bacterium, they just suck that mercury up, methylate it,
send it out, you know, and sometimes it can even become double methylated. So you have
diomethyl mercury, but typically the equilibrium tends to fall on the methyl mercury side.
So once it's deposited, the anaerobic bacteria, bacteria get a hold of it and the
peat and the marsh and the, and the bog and the soil, that slowly gets accumulated up through,
let's say the daphnia, the little, the little water fleas, little water bugs,
and then they accumulate it and then you have the little fish come feed on those,
and then the little fish get fed on slowly but surely by the larger walleye and then,
you know, up the food chain it goes. And so you have a bioaccumulation effect,
a magnification of methyl mercury and say your larger older fish.
And that's why there's always the warnings about the size of the fish and the size of the way.
Exactly. So that's where, yes, that's exactly where the warnings come about regarding the size
of the fish and the age. So you typically want to stay below 20 inches on your fish size for eating.
The sweet spot I would say is around 15 inches to 18 inches.
That's your sweet spot for eating and safety. So what do we know about the peat bumps?
It's a developing field at the moment. It is,
we are learning it is a compound that we are detecting in extremely small quantities.
That's why we had the foil there to help with any cross-contamination.
What we know about PFOS is it's another forever chemical, just like PCBs. PFOS will be around
until we're all dead and gone. It'll be around forever. And so we're monitoring,
all right, let's start where we know. So PFOS, where we expect to find PFOS,
are run-off areas around landfills, airports, and firefighter training areas.
Those are our three main hotspots. So if you live anywhere around there, that
not say per se a modern landfill because now they're being designed to control for that,
but an old landfill that doesn't have per se the liner, you would have
run-off. You see from the leachate off of that landfill, and that leachate would lead into the
waterways. And then you would see from the fish, hopefully first, testing that area,
increased amounts of say PFOS. So PFOS is a catch-all umbrella term for many per folaro
carbon chains. So the main culprits we're looking at are PFOS, PFOS, and PFAS, PFAS,
for right now. There are many others, 15,000 or so to be exact or more.
So but are they, do we know if that's equally distributed? Is that in every element of the
water and the fish and the meat? No, it's not equally distributed. Like I said,
it, like you have your hotspots, right? But I guess if there's a run-off area,
is it all the fish that come through there, or is that what we're still trying to figure out?
Yeah, whether it's in the fillet or if it's constant. Yeah, so we do have data on that. That
comes from Gavin, our PFOS guy. He's in Madison. So he has data that states that the PFOS is
concentrated in the head and he thinks it's the walleye cheeks. But I disagree. I think it's
stuck in the brain because it's, you know, it's a, it's a fatty molecule, but it's not. It's a
believe it kind of mimics cholesterol and, you know, your brain is hot in cholesterol
or it tries to, it gets incorporated there. But that's where the science, we need to know.
We need to know more. So honestly, if I'm, if I want to write a grant, I would write a grant
for Marcus to collect brains and we would sample those brains and see if PFOS is actually concentrated.
But first, we have to find the hotspot to find where these PFOS concentrated fish are. We do
have a few lakes that we know that are hits. And so once we have those, we can actually focus on
those areas and then focus on the fish in that ecosystem to see how that PFOS is actually,
if it is accumulating, where is it accumulating? Is it tissues and certain organs, that sort of
thing. So it's possible that taking a fillet sample to look for PFOS, you may not find it,
even if it is present in that water body, right? Or is it simultaneously testing the water to
determine that that's a hotspot? He's right now you're only testing the water. We're only testing
the fish there. The USGS test the water, other agencies handle water, but we have within our
GIS system, we have it mapped out so that our lakes are chosen that are like highly suspected
to be, you know, contaminated with PFOS. Okay. And that's, I mean, is that a bigger threat long
term than mercury? No, the, I mean, that's comparing apples and oranges that they both
pose their own special threats. I mean, you still have PCBs in the background here. That's the OG
forever chemical. Poly, chlorinated biofuels, PCBs. So in terms of like the work that you guys are
doing here, is it always going to be, but what's the new thing to worry about with the new? Yeah,
kind of. If you want to be a little cynical about it. Yeah, we got methyl mercury. Now we
have PFOS. Soon it'd be microplastics. After that, it'd be six PPD coming out of your tires.
I mean, we're, I mean, we're, this is a, this is a sense of monitoring. So we're not, we're
not going to fix what's happening, but we were able to monitoring to monitor what's happening. So
say, say this is Ruth Lake, Ruth Lake right now may be clean, but I come back five years from now,
my fish are showing numbers that weren't there, that weren't there in the previous years that we
sampled. So now we know that there's activity going around that lake that is running off into
there and we need to alert whoever needs to know so that they can figure out how to control that
point source pollution. So the reason for choosing walleye to do the testing is it just, it's, it's
an apex predator. Apex predator. Everyone wants to. Everyone wants it. It's, it's a, like he says,
a high commodity. It's a fish of the people. I mean, whenever I posted my picture, my selfie
picture, like friends from losing in, they're like, that's a walleye. I was like, yeah, how'd you know?
But yeah, they know. Everyone knows this walleye. So I mean, you got musky too. People love musky,
but nothing compares to the walleye up here as far as efficient. Everyone wants to. Yeah, everyone
wants to. So that, but that's why you would test that. I mean, we also test other fish. We test
sturgeon. We test musky. We test whitefish out of lake superior. We test lake trout out of
lake superior. Right now we're focused on the inland lakes. We do the lake superior in the fall.
We work on the inland lakes in the spring. So like we're in the summer now. So we're wrapping up
the project. All these samples are due Friday. So it's probably hard to imagine that people
whatever is not keep walleye. So no one's going to stop. No one's going to stop. So the best thing
to do is educate. So if I can, if I can convince people to put the big fish up on the wall or
leave it in the water, so it keeps responding to the lakes. And he's shaking his head.
You know, but I mean, you saw that big one. We got 230 grams, nearly half a pound off of one
fillet. So this isn't catching release. Yeah, it's not catching release. So the thing is,
we have to catch an edge cake. So catch edge cake. You can eat a contaminated fish,
but you're going to want to eat a small piece of that fillet. And you're going to want to do a
literature search on anything that can attenuate the toxicity of methyl mercury. And there are
studies out there that have data to back that up. I believe that the top dog in methyl mercury
studies right now is a guy called Michael Ashner. Could be closer retired, but if you go into PubMed,
search methyl mercury, his name is almost on every single publication.
Anything else that we should know? What is the next step? So you guys are just taking
the samples here, and then you bring it over to a lab, right? Right. So typically the next
step they would go in the freezer, but since we're doing a mock trial transport,
I have four samples, four lakes that we're going to do like a little mock trial run.
I'm going to get everything prepped settled. You already got those in the freezer. No,
they're right there. So we had the PFOS, PFOS ones that you saw were the ones wrapped in foil
to help with any kind of cross contamination. The mercury ones were the ones that went into the
bag without any foil. We had the odorless for aging. We have two sets. This time,
typically there's only one set. Our sister agency, KBSC, they're training one of their own
LTEs to how to age the fish. So we get the age, we get the weight, we get the length,
and we get the tissue weight. That's going to be a, I believe that's a wet analysis on that tissue.
And so all these things factor in together to help us know the proper mercury constant of the
tissue as well. And so the, the odorless, one set will go here for our aging purposes here,
and that will go into the database. And then the other set will be going to KBIC, and there they're
going to be doing a quality assurance or quality assessment. So I got this, this is actually a
secret. They're going to find out if there's errors, but I'm checking their numbers, seeing
if they're aging right, and we're going to compare the ages. So it's a lab lab check.
What does KBIC stand for? I don't know.
Kimunabe in the end community. All right. Can you get you to say and spell your name,
give your title while we've got your theater? Do I do the doctor?
All right. My name is Dr. or Joshua Sally, Dr. Joshua Sally, J-O-S-H-U-A-S-A-L-L-E-Y.
I'm originally from Louisiana. I got a job here at Glyphwick beginning in March,
after what my second lived, my second midlife crisis.
And what's your title here? My title here is the environmental toxicologist.
All right. Very cool.