It’s Not If—It’s How Much, How Fast, and What Happens Next

This article is written in direct response to several comments and private messages I received after posting “Let’s Talk About What They’re Not Telling You… Panel Driven Contamination”.

Some folks claimed I was basing my entire concern on just one study. Others suggested I was cherry-picking information to fit a narrative.

So, let’s clear that up.

The Robinson & Meindl (2019) field study—which I highlighted in the previous post—was not the only study I’ve reviewed, nor is it the sole foundation for my concern about solar panel contamination. It was, however, the most compelling place to start because it’s one of the only peer-reviewed studies based on actual field measurements, not theoretical simulations or lab models. That made it especially valuable in cutting through the noise and grounding the conversation in real-world data.

But just because I chose to frame that article around one study doesn’t mean it’s the only source informing my opinion. In fact, I’ve spent considerable time reviewing dozens of additional studies—some with full access, others available only by abstract. Many of them provide further evidence supporting the probability of leaching from photovoltaic systems, under various conditions.

Before we dive in, let me be perfectly clear:

The following information is not a paraphrase, a summary, or my personal interpretation.
What you’re about to read is language pulled directly from the studies themselves—verbatim.
I’ve chosen to quote the source material exactly as written to preserve context, credibility, and to allow you to draw your own conclusions based on the researchers’ own words—not mine.

Many of these, and more, are available on our website: - for your consumption and consideration.

Leaching via Weak Spots in Photovoltaic Modules
“In CdTe containing module pieces, the CdTe itself and the back contact are unstable and highly soluble. In CIGS containing module pieces, all of the module layers are more or less soluble. In the case of c-Si module pieces, the cells’ aluminum back contact is unstable. Module pieces from a-Si technology also show a soluble back contact. Long-term leaching leads to delamination in all kinds of module pieces; delamination depends strongly on the pH value of the solutions.”

“Our long-term experiments clearly demonstrate that it is possible to leach out all, or at least a large amount, of the (toxic) elements from the photovoltaic modules. It is therefore not sufficient to carry out experiments just over 24 h and to conclude on the stability and environmental impact of photovoltaic modules.”

“Most probably, photovoltaic modules, which contain toxic substances, are safe for the users and the environment, at least as long as the modules are not damaged.”

“In fact, it is no longer a question if these substances are released into in the environment: several studies proved they do and that the release depends on the pH-value of the leaching solvents, as well as on the redox conditions.”

“In all kinds of modules, at least one of the layers of the different cell types represents a weak path for the leaching. In the case of CdTe module pieces, the CdTe layer itself and the Mo contact are soluble. In the case of CIGS module pieces, the Zn front contact, the Mo back contact, and the Cd-containing buffer layer are susceptible to strong leaching. For crystalline silicon module pieces, the Al back contact is a weak spot; for amorphous silicon (a-Si) module pieces, also the back contact (Ni) and the intermediate layer containing Zn are identified as weak spots.”

“After 1.5 years of leaching, we observed delamination in all kinds of PV module pieces: c-Si, a-Si, CdTe, and CIGS. The probability of delamination depends on the pH value of the solutions and the experimental conditions. In the case of c-Si module pieces, we always observed 100% delamination, independent of the pH-value, temperature, and agitation: in all aqueous solutions and for all module pieces, delamination occurred.”

“The previous figures, as well as our previous experiments on milled module pieces give the proof for severe leaching for all module technologies.”

“In any case and under all experimental conditions, it is possible to either leach out all or a substantial amount of most elements from the module pieces.”

“During the manufacturing of commercial modules, they are provided with an edge sealing, which should prevent any leaching under normal operating conditions of the (undamaged) modules. However, if the edge sealing of the modules is not carefully done, or if it is damaged, or even worse, if the (front) module glass is broken, leaching is unavoidable. Rain water with pH values always below pH 7 will suffice to leach out the (toxic) elements.”

“In all other cases, in view of the huge amount of installed PV modules, most of them still containing Pb (mostly in the solder of the cell connectors) and/or Cd, they may impose a severe danger to the environment.”

Leaching Hazardous Substances out of Photovoltaic Modules
“Our leaching experiments have demonstrated severe leaching of Pb from c-Si modules and Cd from CdTe modules. In addition, our leaching studies on CdTe modules prove that CdTe is not stable in water based solutions. More than 50 % Cd is leached out within 56 days for pH = 5. In the same time, Te leaches in the range of 30 %, more or less independent from pH, whereas more than 15 % Pb is leached out for pH = 6. In our case, the modules are milled to pieces of 0.2 mm size. Leaching time was several weeks to get information about the time dependence. Disagreements and contradictions in previous studies are solved by considering the pH value of the solutions.”

“So far, the discussion about leaching of hazardous substances mainly concentrated on the element Cd. However, the 80 mg/W content of Pb in c-Si modules, as well as the 75 mg/W silver come close to the 73 mg/W of Cd! Thus, if one discusses toxic materials in PV materials, there is not only a problem in case of CdTe modules but also in case of c-Si! One should also bear in mind that the market share of c-Si modules (≈ 90 %) is much larger than the one of CdTe modules (about 5 %). On the basis of a worldwide installation of 177 GW PV modules in 2014, the c-Si modules with around 158 GW containing 80 mg/W Pb distributed 12800 t of Pb over large areas! In case of CdTe modules with an estimated installation of 8.3 GW, the CdTe modules distributed only 610 t of Cd. Even assuming that Pb is much less toxic than Cd, one must admit that the Pb problem in photovoltaics is much more severe than the one of Cd. From this viewpoint, it is hard to understand why Pb containing solders are still used in PV; lead-free soldering has been a standard in electronic industry for many years. In addition, the c-Si modules of several Japanese producers are completely free of lead!”

Leaching potential of chemical species from real perovskite and silicon solar cells
“Although solar cells are considered safe, economical, and convenient (Xu et al., 2018), environmental concerns are increasing because PV systems contain hazardous substances—mainly heavy metals such as cadmium, copper, lead, nickel, tin, and zinc—which can be released into the environment due to defects in manufacturing, accidental damage, and disposal.”

“Active substances from PV module waste may be released into the environment and can be hazardous to the whole ecosystem.”

“Though PSCs are efficient and cost-effective, their environmental aspects with respect to the toxicity of lead, the main constituent of most halide PSCs (perovskite solar cell), are not yet well evaluated. To the authors’ best knowledge, studies on the leaching of hazardous chemical species from real PSCs are scarce.”

Experimental investigation to evaluate the potential environmental hazards of photovoltaic panels

“Recently the potential environmental hazard of photovoltaic modules together with their management as waste has attracted the attention of scientists. Particular concern is aroused by the several metals contained in photovoltaic panels whose potential release in the environment were scarcely investigated.”

“By considering the technological evolutions in manufacturing, we have shown that during the years crystalline silicon panels have lower tendency to release hazardous metals with respect to thin film panels. In addition, a prediction of the amounts of lead, chromium, cadmium and nickel releasable from next photovoltaic waste was performed. The prevision up to 2050 showed high amounts of lead (30 t) and cadmium (2.9 t) releasable from crystalline and thin film panels respectively.”

“Another important issue is that PV panels can be vulnerable to accidental damages due to fires, thermal shock or atmospheric agents. In these cases, the damaged modules are exposed to rain and the resulting leachates could easily reach the aquatic and terrestrial environment.”

Life cycle analysis of metals in emerging photovoltaic (PV) technologies: A modeling approach to estimate use phase leaching
“these conclusions were reached by neglecting the impacts from non-routine breakage events during the use and emissions to landfills at the end of life of solar cells. These phases were typically not considered due to the expectation that PV materials are typically water-insoluble inorganic compounds and that modules are deployed in robust, hermetically sealed packaging which would preclude emissions during the use phase.”

“Recently, it has been experimentally demonstrated that the environmental impacts from several emerging PV technologies made from perovskite or polymer materials can significantly increase due to metal emissions resulting from exposure to moisture during the use phase.”

“However, in the effort to reduce cost from solar (Graetzel et al., 2012a, b), emerging solar cells often contain water-soluble metal compounds, and these are often packaged in polymeric materials that allow ingress and egress of species even without damage (Wang et al., 2016).”

“This recent work raises the question of whether and under what condition the downstream emissions may still be neglected in comparison to upstream emissions from mining and materials processing. This question coupled with the toxicity concerns of using heavy metals (Benmessaoud et al., 2016) often found in emerging PV is important to consider as society scales PV use to address the Terawatt challenge (Zweibel, 2005).”

“Our results show that the use phase (downstream) emissions of Pb and Cu in perovskite PVs can be more toxic than those of extraction.”

... END OF STUDIES...

Contamination Alone Is Concerning—But Cumulative Impact Amplifies the Risk

It’s one thing to talk about the contamination risk from a single solar project. That alone is cause for concern. But what happens when that risk isn’t isolated—when it’s repeated across dozens of sites in a county, region, or watershed?

That’s the cumulative effect—what some have aptly called the domino effect. Every new solar array brings its own potential for leaching, whether it’s lithium, lead, cadmium, selenium, or PFAS compounds. These substances don’t magically stay contained, and they don’t reset between sites. They stack up. They travel. They accumulate.

And this is where the argument over “property rights” gets turned on its head.

Some insist that opposition to solar developments is a violation of private landowners' rights—as if voicing concern is some kind of uninformed intrusion. But that view ignores a basic reality: what happens on one property doesn’t always stay there. When contaminants leach from one leased field into neighboring soil, shared watersheds, or regional food systems, the impacts don’t respect property lines.

So, while one project might seem tolerable in isolation, the risk it poses doesn’t stay in isolation—not environmentally, not chemically, and not over time. When solar projects are layered across a rural region without oversight of cumulative chemical load, the danger isn’t just repeated—it’s amplified.

This isn’t hysteria. This isn’t misinformation. It’s a valid concern for any community that still values its farmland, water quality, and public health. Because once contamination compounds across parcels, it’s no longer a private matter—it’s a shared consequence.

In Summary -

I want to be transparent here. Many of the studies above are only available in full behind paywalls, and I haven’t paid to download every single one. If I had, I’d be facing a different ethical dilemma—because sharing them in full would be kind of like burning CDs from Napster back in the day. So I’m working with what’s publicly available: the abstracts, summaries, and author conclusions—most of which already raise red flags. Could the full texts further validate my opinion? Maybe. Could some contradict it? That’s also possible.

But here’s the thing - when the abstract alone warns of hazardous leachates, long-term risks, and underestimated downstream emissions, that’s not nothing. In fact, it’s exactly the kind of thing that should spur regulators, communities, and watchdogs into demanding more independent, full-access, field-tested data—before we blanket farmland with industrial-scale arrays.

Now, as I can already hear the next wave of deflection:
“But solar technology is evolving!”

And to that, I say great—let’s talk about it. Healthy debate is good. It sharpens public understanding. But if you’re going to hold up next-gen solar tech as your counterpoint, then do your homework.

Ask yourself:

At what stage is this technology—research, pilot, or mass production?

Will it be affordable enough to actually reach the market anytime soon?

Are the new panels free from toxic materials, or just different kinds of toxic?

Because if what you’re citing is still stuck in the lab—or buried in grant proposals and R&D patents—it could take years, if not decades, to become commercially viable. And chances are, when it finally does, the cost will be astronomical—far beyond what developers are currently spending to scale massive, subsidized projects across rural America.

And let’s not forget—by my own casual review of the literature, many of the “evolving” or “next-generation” solar panels still contain potentially hazardous materials. That hasn’t changed. It’s just wearing a sleeker marketing campaign.

So until we see mainstream, affordable, contaminant-free solar panels in the actual field—not in a lab, not in a PDF, not in a TED Talk—I’ll keep pressing for the facts, quoting the research, and raising the question no one wants to answer:

Is this technology as clean as they claim it is—under the glass?

Postscript:

Here is the link to the Ohio Department of Health position I spoke to in previous articles:

Solar Farms and Photovoltaics Summary and Assessment
https://odh.ohio.gov/wps/wcm/connect/gov/fc124a88-62b4-4e91-b30b-bc1269d0dde5/ODH%2BSolar%2BFarm%2Band%2BPVs%2BSummary%2BAssessments_2022.04.pdf?MOD=AJPERES