Sans Bioaccumulation

We never fear data – even when it contradicts our imagination, or so said the unemployed scientist.

When sewage sludge from King County’s Wastewater Treatment Plants (WWTPs), aka, Publicly Owner Treatment Works (POTWs), none of which actually ‘treat’ anything, is disposed or dumped in our State and private forests, one valid observation is that the toxic sludge kills many life forms, including insects, mosses, worms, nematodes, newts, lizards, shrews, moles, snakes, lichens, higher plants, fungi, and so much more, including even the tree farm trees at higher concentrations. It is, after all, toxic waste, as we continue to show.

Curiously, we note that some mushroom-producing fungi (Basidiomycetes) die outright from toxic sludge exposure, while others fail to produce mushrooms at all, and while others only partially form mushrooms, their reproductive structures, others simply rot away mid-development. What a mess; definitely ecosystem disruption of a higher order.

Such are the adverse effects of toxic waste disposal in a forest ecosystem.

One of my failed assumptions, as it turns out, was that the considerable biomass of fungal mycelia that pervades the organic maze of the forest floor would assimilate and perhaps even bioaccumulate certain of the sludge toxins, with said toxins being evident in the subsequently-produced mushrooms – not so quick!

The first analytical results of the toxin-tolerant mushrooms collected from the sludge piles on the forest floor show no presence at all of any of the battery of toxic Flame Retardants commonly associated with sewage sludge, and for which our results show high concentrations in the disposed sludges and in the aqueous leachates therefrom that seep and flow in the forest soils, wetlands and beyond.

How’d they do that? How do the mushrooms (natural forest fungi) that do not die from toxic sludge exposure, and that appear to be toxin-tolerant, survive the sludge-borne toxins, and develop toxin-free?

The first fungus out of analysis, Polyporus varius, came-up empty on bioaccumulated sludge-borne toxic Flame Retardants. How’d that happen?

 

Polyporus varius, growing on rotted wood on the forest floor that had been drenched in toxic sewage sludge, appears not to have bioaccumulated any of the toxic Flame Retardants tested.

 

Yet other species of fungi, such as these Cup Fungi, appear to thrive by growing directly in and from sewage sludge.

So, either the P. varius that appeared to be growing in the sludge was in fact emerging from its usual substrate of rotted forest wood that was buried in sludge, somehow deriving its nutrients from the wood that was out of reach of the toxins in the forest soils, or perhaps the mushroom was able to protect itself from the array of industrial Flame Retardants and other sludge toxins by metabolizing the toxins into less toxic or non-toxic chemicals that the fungus may have then utilized in some way, or not. The science comes-up short here. Conjecture reigns supreme.

In any case, we are faced with a metabolic mystery for this forest fungus in this toxic environment on this rotted wood.

We have a backlog of the few other forest mushrooms that appear to have survived the toxic onslaught, amongst the many that succumbed outright. More results on this to come.