Why leaving the vast majority of the coal ash in the Dan River is dangerously negligent:
Most species of aquatic insects live in the sediment, collecting, filtering, and grazing upon minute particles of food. Nothing goes to waste down there, not even the arsenic and selenium from coal ash. Heavy metals get lodged into the tissues of any insect that eats them. When minnows eat the insects, they consume the toxins. Larger fish get toxins from every minnow they eat. As you climb higher in the food chain, the amount of arsenic or selenium you find multiplies progressively. This process is called biomagnification and it has impacts on a food web from bottom to top.
NC's Department of Public Health has lifted its recreational advisory (they have yet to post the press release on their website, but I will link to it when they do), telling people it's okay to swim and fish in the River. But they're apparently still advising people to not eat the fish they say it's okay to catch. Which is a contradiction I'm still trying to wrap my mind around. Anyway, back to the science:
There is mounting concern in the scientific, environmental, private, and governmental sectors on a wide range of substances, known as endocrine disruptors, that may interfere with the normal functioning of a living organism's hormone system. Endocrine disruption has the potential to cause:
•immune system, and
•neurological problems, and
Research shows that endocrine disruptors may pose the greatest risk to offspring during prenatal and early postnatal development when organ and neural systems are developing. However, adverse consequences may not be apparent until much later in life.(1) In addition, endocrine disruptors may affect not just the offspring of mothers exposed to endocrine disruptors during pregnancy, but future offspring as well.(2)
Chemicals that mimic or antagonize the:
•female estrogenic hormones,
•male androgenic hormones (such as testosterone), or
are currently receiving the most attention. All three groups are needed to support life in mammals, including people, as well as amphibians, fish, birds, and reptiles. Possible effects on invertebrates also are receiving attention.
Coal ash may contain several of these toxic disruptors, including selenium, arsenic, strontium and vanadium, to name just a few. And when you've got 70 miles of a river affected, with varying levels of coal ash accumulation and silt coverage, the continued bioaccumulation of these toxins is not a question of if, but when and how much.
This nightmare is far from over, and media outlets need to take a much more aggressive stance with DENR, DHHS and (of course) Duke Energy.