This is exactly my thought process.
The rub here is that we’re talking about air pollution being linked to higher cancer risk in patients that live near these plants. Presumably that involves decades of exposure and not just a few years akin to deer’s lifespan. But that pollution probably has some impact on the habitat and plants the deer eat nearby, which may then mean: residents, if they ate browse and mast from trees nearby, would have any even greater risk of cancer.
But deer are also ruminants and because of their complex digestive system, maybe there is a way that they are able to break down and filter out some of the harmful chemicals present in the habitat? I know that cows are able to hold more nutrients in their meat on low-quality diets as compared with chicken/pork because of digestive rumination.
If I let my mind really go on this, it makes me sad to consider how trashed the habitat in my state likely is. I’ve seen bulletins at the NWR I took two deer from telling anglers to be cautious about consuming fish due to elevated levels of mercury in the main boundary river.
The basic answer may be that free-range ruminant deer from anywhere are still more nutritious than a lot of store bought low quality fed meat like chicken/pork.
It all comes down to the specific pollutants and their chemical properties. I'm a chemical and also environmental engineer by degree and have spent a bit of time in industry looking at the topics. Every chemical is different. You have to consider whether it is an acute risk or a persistent one. An acute toxin could be something like Hydrochloric acid or sodium hydroxide. Both dissolve in water and after a little dilution are harmless. In high concentrations (e.g. a train tanker spill) they are deadly immediately and for as long as it takes to dilute them away. For example, this was about 5 miles upstream from our cabin. It ruined 30 miles of a stream for years. The risk was gone after a week or so (you could wade the creek at that point) but the damage was done and significant. In this case, because it was an accute toxin and not something bioaccumulative it wasn't something that persisted over time.
A Norfolk-Southern train derailed early Friday morning near Gardeau in Norwich Township, dumping about 16,000 gallons of liquid sodium hydroxide onto the ground and into Portage Run, a branch of
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Today, Portage Run, a branch of the Sinnemahoning Creek in McKean and Cameron counties, is filled with all kinds of aquatic life, everything from minnows to sportfish.
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Toxins like lead, mercury, and PCBs are bioaccumulative. They absorb into the fatty tissues of living things and more or less can't be processed or excreted. A tiny exposure once isn't going to kill you. Even a large exposure once probably won't kill you. But exposure over time will cause buildup and future ails. This is where our chemical knowledge is more limited. When chemicals are developed or tested for toxicity, most testing is done on rats, minnows, and occasionally other animals. Most common is LD50 testing, which is the lethal dose needed to kill 50% of the test population. That's a very accute test and doesn't translate well to long term buildup. That's why we don't know of the environmental impact of many chemicals until they have been in the environment for a long time and studies can be done to assess the impact. Leaded gas was great for engines. Not so much for the environment. Basically everything that rain touches is contaminated with lead right now.
Mode of exposure is the other consideration. Skin exposure, inhalation, and consumption (eating) are very different modes of exposure. Eat all of the fine particles you want but don't inhale them. The more persistive chemicals tend to be things you eat. That's because of bioaccumulation. Mercury in Tuna is the usual example- algae absorb mercury at teeny tiny concentration. Filter feeders eat the algae and concentrate it. Little fish eat the filter feeders, big fish eat the little fish, tuna eat the big fish. At each step the concentration is increased because nothing can process it. Fatty tissues in the liver can't excrete them so the chemicals build up there (and other fatty tissues).
I don't know the chemicals of concern down there, but you mentioned air pollution as the driver. That makes sense for being around refineries since they are leaky as all get out and will be constantly emitting petrochemical gasses. If that's the primary issue then I wouldn't worry about eating deer. Deer are going to be 2-5 years old and you're not eating their lungs. If its something more noxious then I'd do some digging on what it is and go from there.