When I originally wrote SolveEczema.org, I always understood that a medical study or publication would be necessary to bring the ideas into the medical mainstream. I did the site because I wanted to help as many people as possible in the meantime.
I have also always realized there are other implications to these ideas beyond eczema, but didn’t feel in a position to write about them. I was moved recently by reading a Science News story about bat white nose syndrome, which is so lethal, the word “extinction” is being bandied about. I spent weeks composing an email to a respected bat researcher who is on the forefront of trying to save these beneficial creatures. I’m sure this is going to seem like it’s coming from left field, so it’s unlikely to make an impact. But as with writing the SolveEczema.org site in the first place, I had to try.
I’m posting the letter here, edited for clarity, as it again discusses some of some of the ideas underlying SolveEczema.org.
–A.J. Lumsdaine
Dear Dr. Reeder,
I have followed your work on bat white-nose syndrome in lay publications like Science News. I have for many years been concerned that something like this could happen to bats because of an unrecognized environmental influence that, if at issue, I’m surprised took even this long to cause such devastation.
I have to ask you to please bear with me while I explain. There are so many preconceived notions to overcome about what I am about to say, there isn’t really an easy way to say it.
For 8 years now, I have run a noncommercial website with a novel approach to eczema and allergies that helps families ameliorate or eliminate their children’s eczema and other atopic manifestations like asthma without any treatment, by getting to the environmental cause. Yes, I realize bats don’t get eczema, but please bear with me. The site has been used by people all over the world, including doctors for their own families, and has inspired a green cleaning book. Last year alone, even though I don’t do any advertising or optimization, the site had nearly 40,000 unique visitors and 130,000 page views/360,000 hits, plus many thousands more on the associated blog. Around 80% of the visits are from bookmarks and direct links, only 20% from search engine links, meaning most visits are from people referring the information to each other and returning themselves.
If you want to see a well-written, well-documented anecdotal demonstration of this, a mom in Georgia has been blogging about using my website to help her once severely eczematous son lead a normal life without treatment (that’s him on the right before she found my website): http://www.sammysskin.blogspot.com Again, this does relate to bats, please bear with me.
Eczema, asthma, and allergy rates have risen precipitously in many nations around the world since WWII, affecting nearly every other child in some hotspots. Dogs and cats, by the way, face a concurrent increase in eczema and other atopic manifestations like allergies. Most mainstream medical researchers acknowledge that even though there appears to be a genetic susceptibility, given the rapid rise, and how those who move from geographical regions with less eczema to regions with more eczema acquire eczema at the higher rates, the cause must be primarily environmental.
People are using my website to not only eliminate their eczema, but also their asthma, allergies, and dry skin, in the way the underlying basis predicts. The underlying problem is the way modern synthetic detergents — which are dramatically more hydrophilic and oleophilic than the surfactants (soaps) used by humans for thousands of years prior — affect the skin barrier, causing excess water loss and thinning of membranes. The reason detergents cause such dramatic effects is not because, as is traditionally believed, washing products strip the skin of oils. In my observation, it’s because residues that persist on the skin directly increase the permeability and cause excess water loss as a result, even just those residues that migrate from contact with clothing washed in detergent, or detergent-laden dust. Ingested detergents on dishes and even in processed foods, and inhaled detergents in dust (which is predominantly skin cells and lint in modern indoor environments, in other words, full of detergents) affect lung and gut membranes as well. The surprise was that ingested detergents also affect skin membranes. In my experience, the eczema is expressed proportionally to permeability increases.
Everyone, not just those expressing eczema, appears to be affected and experiences degradation of the skin barrier and other membranes. Only some people, especially children whose skin is naturally more permeable and absorbs more detergents (and proportionally so), experience the eczema more readily. Detergents also facilitate antigen penetration of membranes and thus overall antigen load, and can negatively impact sensitive membrane healing times.
It is my belief — and I realize these are all just my ideas but they do happen to lead to real solutions for many, many individuals who could not find those solutions in standard approaches on the subject — that the expression of eczema is, under normal environmental conditions and in the absence of these modern exposures, a “healthy” signal from the immune system to the conscious brain when faced with too much allergen/antigen in the environment, under that immune system’s particular conditions at the time, in the same way that pain serves the nervous system (mostly as a warning to the conscious brain). The classic interpretation of allergy is that the immune system becomes confused and attacks the body, but my interpretation is that allergens being similar to pathogens to the immune system, require more energy to differentiate between them. If the immune system can “tell” the conscious brain to offload allergens to better and more accurately face a microbial threat, for example, allergy could confer a survival advantage. Aeroallergens typically produce respiratory symptoms, contact allergens cause skin symptoms, etc. There is a roughly linear relationship between eczema rates and atopy by nation, and in societies where there is very little of both, the rates of eczema can be very, very small, i.e., the triggering of that signal is uncommon and could be beneficial.
In other words, I believe the eczema itself is a signal that some people express, under certain genetic and physical conditions. Eczema isn’t a problem that affects one person and never the next, there is a continuum, where more and more people are affected as the environmental cause increases. Everyone has the potential to express this signal. In severe atopic dermatitis, the inputs, feedback, skin barrier, immune response, and expression of the signal are all abnormal and out of control because of modern environmental influences, overwhelmingly, I believe, detergents. The signal is expressed for some people as certain thresholds are crossed, for more and more people as the exposures increase. Remove those influences, and people can be completely normal, without treatment of any kind. In order to accomplish that, typically a whole household must make the changes, and inevitably, everyone in the household experiences surprising benefits — most notably to skin but also allergy — not just the person who had eczema.
Please continue to bear with me, this is absolutely relevant to bats. It’s very important to realize that there can be very substantial physiological effects from very tiny exposures. And in the presence of small amounts of water — sweat, for example, or other membrane surface dampness or condensation — the effect on permeability is dramatically amplified.
In the course of using the website to eliminate eczema, if properly implemented, it is a universal experience that everyone in a household undergoes a beneficial change in their skin, even if they don’t have eczema or atopy. Over the course of about two months, the skin becomes completely different: thicker, more supple, and less dry. Most people are eventually able to wash with soap and stop using moisturizers. This happens for anyone, for people who use the site just to eliminate dry skin.
It’s clear, too, from empirical observation, that many people with eczema are affected by fungal organisms (and sometimes bacterial) while the skin is compromised, and those areas must be treated to kill the fungal organisms before the skin will completely heal. Research (with no cognizance of this detergent issue) also shows that people with eczema are more susceptible to infections on affected skin than people with skin conditions that also disrupt the skin, like psoriasis. Research with detergents on sensitive eye membranes show they can substantially increase healing times.
Since fungal cells are more like mammalian cells than they are even like bacterial cells, and those fungal cells can replace mammalian cells, it’s necessary to be extremely careful in treating those “infections” or colonizations because if the fungal cells die off all at once, the result could be an alarming and even more compromising loss of skin, such as sloughing off of large surface areas and bleeding depending on how affected it is. If antifungal treatment is ramped up very, very slowly over time, though, die-off is minimized and normalization of the skin can be achieved over time without the risks associated with sudden die off. Fortunately, fungal organisms tend to grow slowly, so this process works better with fungal organisms than you might expect with bacterial.
Here’s why I believe this is important to bats and specifically to your work: First of all, the obvious: bats’ wings are mostly skin. Bats (and frogs) live at that land-water/wet-dry interface, in other words, where they would constantly be affected by the small amounts of water that amplify the detergent effect on membranes I described above. Although bats to my understanding stay in dry parts of caves, they do live in cool, dark, damp places where fungal organisms can be very opportunistic if a modern influence were to so fundamentally compromise bats’ evolved defenses. In other words, bats and frogs would in theory be most affected by detergent pollution, the proverbial “canaries in the coalmine”. It’s interesting that in Australia, Roundup was banned until the maker removed, not the poison, but the detergent in it which was killing frogs.
Detergents are ubiquitous outdoor environmental pollutants now, especially in aquatic environments. Their use has been on the rise outdoors as well as indoors in recent decades. They are readily absorbed (attached to, really) by living membranes. Bats in particular would be susceptible to exposure, as bats eat a lot of insects, obviously, and presently virtually all pesticides and herbicides for large-scale use are mixed and sprayed with detergents in order to reduce surface tension and spread the active ingredients more evenly. New biological controls intended to reduce poison use and highly target certain bad bugs without harming the good ones, if sprayed with detergents (as is almost certainly the case), may be having the unintended consequence of exposing bats to more ingested detergents as they consume non-targeted insects that have detergents on them. Bats could also outright come into contact with sprays or dusts, or detergents in water, and it doesn’t take much.
If detergents affect bat membranes the way they do human skin – and I see no reason they wouldn’t – detergents would both degrade bat membranes (thinning the wings) and make them more susceptible to fungal colonization. Ingesting detergents also appears to cause eczema and membrane degradation in human skin — difficult-to-correlate membrane degradation even in humans who do not express eczema — and can do so in very, very small quantities. Although other mammals may not express eczema, which as I believe is an evolved signal/adaptation and not the direct effect of detergent contact irritation, the underlying basis for the skin barrier dysfunction would almost certainly extend to other mammals, whether they express eczema or not. Since humans and presumably other mammals use endogenous surfactants in critical functions of life, including to control skin membrane permeability, it makes sense that exogenous detergents could throw a monkey wrench in this adaptation. It’s also very possible that there is no adaptation that would allow for a survival advantage to bats by expressing this signal of eczema as there would be for larger mammals. In other words, there is no reason to believe bats would experience any benefit from eczema as humans and perhaps even their pets would, so any corresponding genes would have died out long ago. Nevertheless, bats (and frogs) would experience negative impacts to their membranes from significant exposure to exogenous detergent sources.
I want to reiterate that ingested detergents, even in small quantities, can cause surprisingly significant physiological effects. The amount of detergent that penetrates the skin of a banana or shell of an egg from normal processing practices, if ingested, is enough to cause patches of skin changes in susceptible infants. These are some of the most minor influences in a home today, in the most susceptible group — I am just pointing out that if other influences are effectively controlled, in the most susceptible (babies), even such minor influences can have visible effects. How much more detergent are bats undoubtedly consuming and contacting relative to their body weight and skin surface these days?
I have witnessed infants go from clear skin to bubbly, itchy, severe-looking rash in 20 minutes just from contact with the clothing of an adult who was substantially detergent-free except for face wash or moisturizer containing detergents, with no direct skin-to-skin contact. I have seen this even from an adult, in similar circumstances, simply leaning over a susceptible infant, without any direct contact. If these children are removed from the exposure and washed immediately with ordinary soap (see my site for how “soap” is defined, very important) to remove detergents, reversal of even a severe rash to normal skin (provided the infant has been living in a substantially detergent-free environment already) can be just as rapid and stunning.
I think in order for researchers to truly figure out whether it’s possible to help the bats they are studying to recover, researchers probably need to remove that environmental influence from their labs and persons completely. If researchers are not detergent-free, they are producing detergent-laden dust that would affect creatures as tiny as bats, with already compromised membranes, in ways most people could never imagine. Understanding these influences from the detergent-eczema arena could shed light on how and why bats are being affected, and how to help them in new ways. It’s not as difficult as it might sound to achieve results, but it’s necessary to really understand and these are my own novel ideas, not yet in the mainstream of eczema research. But they are helping a great many people worldwide in the way the underlying ideas would suggest.
I want to propose to you that this line of inquiry is worth looking into, because if detergents are indeed an unrecognized factor in worldwide frog and bat population crashes, rescue of bats may be more effective, and the long-term solutions could be straightforward, if not simple. People making newer biological controls for targeted insecticides may simply need to take care to use only surfactants which are no more hydrophilic than typical alkaline soaps, for example.
In one interview I read recently, you are quoted as saying, “For a long time, a lot of us — myself included — said fungal infections don’t kill mammals, so that can’t be what’s killing the bats. But it turns out that because of the bat’s unique hibernation cycle and the nature of the fungus, it does kill them. The big question now is: Can we prevent extinction?” You may be surprised to learn of a growing body of research discussing new kinds of fungal susceptibilities, colonizations and diseases in humans, especially children, because of modern influences. Like you, researchers believed these microorganisms had no role in human disease — until a variety of new influences like chronic use of steroids or antibiotics — and I would personally add, detergents — created new susceptibilities especially in vulnerable populations. Given what I have learned over the years about detergents and eczema, I think it’s highly likely that detergent pollution plays a central role in susceptibility of bats to fungal diseases.
Over the years, I have occasionally sent letters like this to researchers without response. It’s very likely my letters just end up in spam folders, as I expect this one is likely to. So I am posting it on my blog as well, in hopes that one of my readers may have a bat researcher in their lives with whom they can share it. This letter also happens to explain the underlying concepts again which, if nothing else, also helps my readers.
I am moved by the specter of the extinction of these beneficial creatures; I hope this letter proves useful to you. Thank you for taking the time to consider my input. I wish you all the best in your work to save bats from this urgent threat.
Sincerely,
A.J. Lumsdaine
http://www.SolveEczema.org
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This work by A.J. Lumsdaine is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.
hello,
i came across your blog post here: https://solveeczema.org/eczemablog/?cat=3 – and wanted to point out that the fungus (geomyces destructans) that has been identified as causing WNS in north-american bats stems from europe. all of the bats there, i would assume, are equally exposed to insecticides & added detergents as the north-american species. most likely their exposure is, in fact, far greater.
yet, said fungus rarely cause mortalities in european bats. also, bats are generally hosts of various fungi – and have been so for millennia – gd is only one of them.
greetings,
corinna
HI Corinna,
Thanks for your email. I am very familiar with what has been published in regards to fungus and WNS as well as what’s happening to amphibians worldwide. I’m not arguing that, in fact I wrote my post assuming people are familiar. The impact of detergents on membranes affects susceptibility to fungal colonization.
As you note, bats are hosts of fungi and have evolved to live in conditions where fungi thrive. Why the sudden susceptibility? Do bats have periodic catastrophic die off from different fungal species as part of their recent evolution? I don’t think so. Even if they have, the fact remains that they are being exposed to these pollutants that also have a severe and unrecognized impact on the skin of humans and their domestic pets, and would on bats as well. The presence of dampness significantly amplifies that effect, so animals who live in these damp environments would be most affected.
I’m just curious as to why you would assume bats in Europe would be equally exposed to detergents? Europeans have used efficient laundering equipment far longer and more widely, don’t wash their clothing as often as Americans, nor frankly shower as often or as wastefully, and tend not to have large lawns doused regularly with insecticides. Across large swaths of the Midwest, the poison truck comes and sprays down lawn after lawn on a regular basis. There is no equivalent to this in Europe. There has been a more widespread attention to organic farming production and sustainability in Europe in recent years than in America. The Germans and Swiss, for example, have conducted extensive monitoring programs for detergents in rivers. Concentration depends on a few factors including consumer habits, which again, are higher in the US. Lower use, lower concentrations. Per capita consumption of surfactants and detergents is higher in North America than Europe. Surfactant consumption worldwide is dominated by household detergents, industrial applications including agrochemicals account for about 10% of consumption (though likely represent a greater share of what ends up in outdoor aquatic environments, and as I mentioned on my site, the development of these highly targeted insecticides is relatively recent).
I think the potential for this unrecognized influence to play a major role in this epidemic is logically there, and should be studied. At the very least, having some knowledge of this phenomenon in humans could help improve survivability of sick bats brought into lab environments. Given what I have learned over the years by helping people eliminate their children’s or their own eczema and atopic manifestations, I think there is almost no way detergents don’t play at least some role in what is happening to bats and amphibians.
Thanks for your email, I will look at my post again to see if I should change it to be sure it doesn’t sound like I am arguing against the influence of fungus in WNS, I hadn’t thought so, but I’ll look.
Kind Regards,
AJ
hello AJ,
thank you for your prompt reply – much appreciated!
i am new to the phenomenon of WNS and only started researching it during the last weeks – however, i have since dedicated a considerable time to it, including talking to researchers and biologists as well as people rehabilitation bats in the US as well as here in canada where the fungus has only hit our bat population in the past 2 years and reached our area as of lately.
one of the ‘rehabbers’ i talked to is swearing by the use of diluted apple cider as a means to heal the wings of the bats which prompted me to look into the application of vinegar in fungus infections. this led me to your post.
i am from europe and am familiar with the lifestyle of people in germany, switzerland, england and france – and although the use of detergent differs as you say, the density of people per square km is much higher. also, while certainly no trucks are dousing gardens with insecticides, people pretty much do this themselves. in addition, i assume you are referring to life in the so-called ‘suburbs’. america still has large uninhabited areas and while europe is not only densely populated, suburbs make out a large portion of land use.
but apart from these differences and since you are familiar with the studies on bats, i trust you know that healthy north-american bats have been exposed in a controlled environment to the fungus strain from europe. all showed the same level of deterioration as recorded since the wave has started to sweep across the country starting from albany, ny… it was deducted from this experiment that GD was indeed introduced from europe, is new in NA and bats here have not (yet) develop resistance to it, explaining their high mortality.
if, in fact, as you say bats are affected by insecticides – respectively the detergent in them – their die-off would not have developed in a wave-like fashion, which is more consistent with an unfamiliar pathogen being introduced to a population that has not had time to evolve with it and develop resistance to it – something the replication in the laboratory has also shown.
also, i don’t see you addressing these points… ;-))
instead i wonder if you could maybe enlighten me re: the use of vinegar on skin infected by fungi. how do you feel about this practice on the wings of GD infected bats?
greetings,
corinna
Hi Corinna,
I can see you’re very passionate about this issue, and I think that’s great that you have been investigating this. One thing I would urge you to do is to gather information and data without drawing sweeping conclusions that could wall off whole avenues of inquiry for tenuous reasons. Differentiate between what you know to be true, and what you assume, and wait to draw conclusions until you know more.
In my blog post, I make a case for a line of inquiry, not drawing conclusions. Your points have served to strengthen the case I have made, but it would take a lot of work to bring you up to speed, work I can’t do for people whose children are very sick, which is why I wrote the website.
You are not familiar with my website, so it’s difficult to even have this discussion. I now have a theory about why eczema and asthma have arisen in the latter half of the 20th century that is consistent with all available research, it’s just a very different interpretation. In contrast to other theories, it happens to lead to my being able to help people with even very severe eczema and often other atopic manifestations like asthma, to not only eliminate their eczema, but also their atopic manifestations, and to normalize their skin integrity and skin barrier, without any treatment. The site is very detailed and involved precisely because there are so many preconceived notions that are difficult to disavow people of. I only put up my website to help whatever people could be helped until scientific study could be done, but in the years since it has been up, it has become very clear that the willingness and ability to understand the principles is directly related to the level of suffering as people go into it. It’s otherwise very difficult to get people to put the energy into understanding what’s there until there is more traditional scientific study, because I am putting forward a radically different interpretation. Just the idea that eczema is solvable and preventable without treatment, and is something about the environment that can be discerned, is so radical, just accepting that the problem can be solved gets people more than halfway there.
So, as I said, it’s very difficult to even have this discussion with you, because I can’t really bring you up to speed in a discussion like this. Perhaps you will do me the courtesy of at least watching the video on my website before answering again. I’m not certain it would be enough, because you wouldn’t have the benefit of seeing the principles in practice, as people who are desperate to help their children are motivated to do (so that they overcome pre-existing biases, which is tough). But doctors with experience in this area who actually take the time to read through all of the material have been to a one supportive, often recommending the site to patients, because they get it, whereas if they just assume they know what it’s about, they are to a one dismissive.
Because if you understood the site principles, you might understand why apple cider vinegar is used by so many people with eczema — those who do not have the solution, but are empirically looking for things that help them. There are two reasons vinegar is helpful: it does such a good job removing detergents (and they do not realize the detergent influence underlying the barrier disruption), and vinegar is antifungal (people whose skin barrier is compromised in this way are more susceptible to fungal colonization of the skin).
Unless researchers understood the real impacts of even small exposures to detergents on membranes, and knew how to remove that environmental influence from their labs and persons completely, they would have no way of knowing how much the ACV was benefiting the bats because of removing detergents from their membranes versus how much was because of antifungal effects, or both. It’s interesting that diluted apple cider vinegar swabs would be directly helpful, as it would be with detergent removal, because often antifungal action first produces a worsening of symptoms and inflammation before things improve. (Here’s just a random example: http://link.springer.com/article/10.2165/00128071-200607050-00007#page-2 )
That is not to say one could conclude anything relative to whether it was antifungal because it didn’t first produce a temporary inflammatory flare-up, because the researcher may know enough to reduce the dilution to the point where the inflammation doesn’t occur (and ramp up the concentration slowly over time to avoid the inflammation response, I have even suggested this to bat researchers in the past, in particular one who had used antifungal medication and found to her surprise that it killed the bats), or it may not have occurred for other reasons, but it’s interesting that they saw such a direct benefit rather than a worsening.
You seem not to be hearing that I am in no way disagreeing with the role of fungi in WNS. Nothing I am saying is inconsistent with anything that has been published about this issue (in regards to facts, rather than interpretations). I am speaking to the potential, unrecognized role of detergents in altering membranes and susceptibility. Why would this be inconsistent with bats being more susceptible to a new pathogen, or even the bats in the lab being susceptible to that pathogen when directly infected? You still haven’t addressed the issue of whether this even makes any sense in the evolution of bats for them to suddenly become so catastrophically affected by even a new fungus. In the absence of detergents, would they be so affected? That’s a question all the evidence suggest could help lead to answers in this epidemic. Could. We don’t know. It’s a question for which there is enough suggestion that an answer is worth the investigating.
Your bringing up ACV in this way is strikingly similar to the frequent use of ACV with people who don’t go far enough to solve their eczema but try everything under the sun randomly searching for some empirical improvements. I often recommend people use ACV (in part for antifungal purposes) when they use my website. There’s a mom blogger with a bulletin board of people implementing my site, with whole discussion threads about ACV, because I first suggested to her to try it to address persistent fungal involvement in her child’s skin resulting from previous long-term skin barrier disruption. Does that prove anything in our discussion? No, not really. But it’s interesting, and weighs even more in favor of looking at this avenue. In fact, I wonder if you would be willing to give me the contact information of the researcher getting good results with ACV?
The effect of detergents on humans has been relatively recent and growing. Specifically for bats, targeted insecticides which, instead of killing all insects to which they are applied, leave most of the insects alive (but covered with detergents) except the targeted insect, are very recent innovations, and would lead to a sudden increase in the amount of ingested detergents. The timing of the epidemic is actually suggestive of a pollutant-related susceptibility. Again, this doesn’t PROVE anything, it simply raises questions that suggest inquiry.
Another parallel here to my site is that I really came to my interpretation from an underlying belief in the strength and robustness of the human system at this point in our evolution. The prevailing view — with a bias toward seeing fragility where it makes no sense to assume it — is to see every disease as stemming from a defect, even though most researchers acknowledge that for fundamental biological reasons, the eczema epidemic has to be primarily environmental. When people thank me after using the site to help their children, I will then sometimes use the occasion to remind them there was never anything wrong with their child, it was something about the environment. People assume it’s something about their child, a defect in their child, because not everyone gets eczema, but I have come to see that the eczema is a signal that goes haywire because of environmental pollution, and just because not everyone has eczema in a given environment does not mean everyone isn’t experiencing skin or health effects.
I believe the same for bats. It makes no sense to me that bats would be so fragile as to be so catastrophically affected by any fungal species given their evolution in damp environments, without at least some other factor increasing their susceptibility. Frogs too. I am not aware of periodic catastrophic die off as the norm in the recent evolution of bats, but even if it were so, there are good reasons to investigate a significant potential factor in susceptibility, and include the potential impact of these ubiquitous pollutants in researching this problem.
In trying to argue, you’re speaking about populations as if those points could determine how much detergent bats are exposed to or how they are exposed to them or as if you could somehow negate the possibility of that influence. Detergents are ubiquitous aquatic pollutants worldwide. One can note the difference between the European and American fungal mortality, detergent use, etc., but our discussion in no way either negates nor proves whether detergents are involved, or whether they are suspect. We can only suggest lines of inquiry, the proof would have to happen in a lab. I am merely pointing out an avenue the researchers would not have considered, and for which there is much reason to consider.
We can bring up these different factors, but bottom line, Europe has fewer people and lower per capita use of detergent. Large lawns and the wholesale application of pesticides from tanker trucks on a regular basis in residential areas is an unknown phenomenon in Europe, and not something individuals could come close to reproducing by individual applications. Switzerland pays a lot of attention to reducing pollutants in their waterways, for example, and they tend to be more proactive. The amount of pollution in aquatic environments is likely to be significantly affected when surfactants are introduced by untreated wastewater or runoff. The Swiss are far less likely to make large untreated discharges of wastewater than any similarly populated large American city. My mother is European and we spent most of a recent summer there with our son, where I got a pretty good idea of the differences and similarities in the use of household detergents. Density of people per square mile is irrelevant because as you say much of the US has few people per sq mile, but our population centers are larger and just as densely populated and our usage is different. The point is, this discussion line neither proves nor disproves what bats themselves are exposed to. It serves no reasonable scientific purpose to dismiss a connection offhand based on such a tenuous discussion.
All the best with your inquiries. I hope you will make a difference as a “citizen scientist”!
Best,
AJ