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Tue Apr 3, 2018, 10:31 PM

Tracking the Source of Fecal Contamination in Recreational Freshwater.

You see stuff like this, and you really don't want to believe it:


Solar Works Wherever People Live


It is a bourgeois conceit - and regrettably it is prevalent on our end of the political spectrum - that so called "renewable energy" is a viable solution to poverty on this planet, poverty being something about which very few of us actually know anything at all and about which we care even less.

Here's a clue: The overwhelming majority of people who live in bamboo and grass huts are not looking for a solar cell to power their video games. In fact, the main effect that solar cells is likely to have in the third world will be to raise the serum levels of toxic metals in children of all ages when this stuff turns into electronic waste - which it will before most middle aged bourgeois people die - and is sent to third world countries to be "recycled" so everyone in rich countries can feel all "green."

Solar energy is useless in the first world, and if anything it is worse than useless in the third world, given, as is the case with everything else, the lives of third world human beings are considered expendable in order to provide for the smug complacency associated with citizens of the first world. The third world is where the most toxic materials for "green" renewable energy is mostly mined, and it will be the place where most of it will end up being dumped.

It's disgusting.

One of the largest health risks in the third world, besides air pollution for which the solar industry has just racked up half a century of doing nothing to address - is the lack of adequate sanitation.

Some notes from the World Health Organization's "fact sheet" associated with this issue:

13% of the global population (0.9 billion people) used toilets or latrines where excreta were disposed of in situ.

68% of the world’s population (5.0 billion people) used at least a basic sanitation service.

2.3 billion people still do not have basic sanitation facilities such as toilets or latrines.

Of these, 892 million still defecate in the open, for example in street gutters, behind bushes or into open bodies of water.
At least 10% of the world’s population is thought to consume food irrigated by wastewater.

Poor sanitation is linked to transmission of diseases such as cholera, diarrhoea, dysentery, hepatitis A, typhoid and polio.

Inadequate sanitation is estimated to cause 280 000 diarrhoeal deaths annually and is a major factor in several neglected tropical diseases, including intestinal worms, schistosomiasis, and trachoma. Poor sanitation also contributes to malnutrition.

WHO Fact Sheet: Sanitation

We may all feel smug about this not being our problem, although I can tell you my septic system failed a few years back and I got a new appreciation of this issue, even though I'd been considering it sometime.

A paper published in the current issue of Environmental Science and Technology suggests that even if it's not the same level of problem as it is for people living in grass huts powered by swell solar cells, maybe cadmium telluride babies, it's not entirely trivial for first world bourgeois types.

The paper is here:

Application of SourceTracker for Accurate Identification of Fecal Pollution in Recreational Freshwater: A Double-Blinded Study (Sadowsky et al, Environ. Sci. Technol., 2018, 52 (7), pp 4207–4217)

From the introductory text:

Fecal pollution of water is a significant global health issue due to the likely presence of waterborne pathogens. Therefore, identification of the source(s) of fecal pollution is critical for implementing appropriate remediation strategies and protecting human health risks associated with water use and reuse. Fecal pollution of environmental waters has been historically assessed by enumerating fecal indicator bacteria (FIB), such as Escherichia coli, Enterococcus spp., and Clostridium perfringens using culture-based methods.(1) However, monitoring FIB in environmental waters does not provide information on the source of pollution, e.g., human or animal feces,(2) or naturalized FIB in the environment,(3,4) necessitating the use of microbial source tracking (MST) methodologies. Early MST tools were library-dependent and required isolation and typing of hundreds-to-thousands of FIB from human and animal feces to generate source-associated libraries.(5−7) Conversely, library-independent methods target a gene fragment from a taxonomic group that typically coevolved, or is otherwise associated (e.g., by infection), with a specific host, providing a host-associated marker typically enumerated by quantitative PCR (qPCR).(2)...

The authors note that the most modern methods, based on qPCR technology, for determining the source of fecal matter has demonstrated ambiguities which they seek to resolve using machine learning type algorithms.

The goal is to distinguish fecal sources from horse, cows, cats, dogs and wastewater treatment plants (WWTP). The study was double blinded to determine the accuracy of their methods.

I don't have much time this evening, and won't go through the paper in any detail, but will show some pictures from the paper along with captions, and then offer some text from the conclusion:

The caption:

Figure 1. Principal coordinate analyses of Bray–Curtis dissimilarities among source bacterial communities. Samples were broadly grouped to host categories including A) domestic (r2 = 0.43); B) livestock (r2 = 0.82); C) avian (r2 = 0.30); D) wildlife (r2 = 0.47); E) WWTP (r2 = 0.71); and F) WWTP + avian (r2 = 0.52). MN: Minnesota. The five most abundant genera in each host category are shown and were overlaid on the ordination using the corr.axes command in mothur

The caption:

Figure 2. Linear discriminant analyses of effect sizes (LEfSe) showing differentially abundant OTUs classified to genera. Sources were broadly grouped to host categories which included A) domestic, B) livestock, C) avian, D) wildlife, E) WWTP, and F) WWTP + avian. All analyses were performed at LDA ≥ 4.0. Abbreviations: CA: California; Chick: chicken; H: Hobart; Kang: kangaroo; M: Melbourne; QLD: Queensland.

An "OTU" is an "Operational Taxonomic Unit."

Figure 3. Sink predictions among source categories, with respect to geography, in the initial library. Sources were broadly grouped to host categories which included A) domestic, B) livestock, C) avian, D) wildlife, E) WWTP, and F) WWTP + avian. Approximately half of the samples in each category were assigned as a source and the other half used as sink (shown in parentheses). Error bars reflect standard deviations. The “Unknown” prediction refers to the proportion of the community that was not assigned to a source. Abbreviations: B: Brisbane; CA: California; Chick: chicken; H: Hobart; M: Melbourne; MN: Minnesota; P: Perth; QLD: Queensland.

Figure 4. Genera classifications of OTUs assigned to sinks from the respective source using SourceTracker. Sources were broadly grouped to host categories which included A) domestic, B) livestock, C) avian, D) wildlife, E) WWTP, and F) WWTP + avian. Approximately half of the samples in each category was assigned as a source, and the other half was used as sink. Abundances were normalized to the total sink prediction for each source (Figure 3). Abbreviations: CA: California; Kang: kangaroo; QLD: Queensland.

Some concluding remarks:

Results of this study indicate that identification of fecal source contamination in recreational freshwater using SourceTracker is dependent on the inclusion of geographically associated source samples present in the source library. Using an initial library with geographically divergent sources, but no representation from local sources, blinded source samples could not be unambiguously defined, with mean similarities of blinded source communities <7% to sources in the initial fecal library. Furthermore, despite a great overlap in community composition among certain host species, e.g., avian species, the algorithm was generally able to assign >80% of the sink community to the correct source and geography. These results suggest that, despite taxonomic similarity in the fecal microbial community among closely related sources,(40) individuals vary by geographic region and specific species compositions (here assessed as OTUs), as has been well documented among humans.(41,42)

If you're curious about actual sources of actual shit, you may click on the link to the paper, which is probably not open sourced, and then find the "SI" supplemental information PDF link and open it. This should be open sourced, and you can learn whence shit in recreational waters comes.

You know, we're surely not perfect on the left, and it is not enough to say we're not as bat shit mad as the people on the right, including the orange baboon in the White House. It is not enough to be "not as bad as..."

The challenge is to be good; to be decent, and decency involves, well, to go with the theme here, "giving a shit."

We should care as much about the people in the third world who are described in the WHO fact sheet, as we do about how bad walking our dogs on the beach is for water skiiers.

Just saying...

We can be so clueless:

Solar cells on grass huts...you see this kind of thing, but you really don't want to believe it.

Have a nice "hump day" tomorrow.

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