Living Next to Geothermal Power: What the Research Says About Cancer Risks

By Jasmine Steiner, KahuPuna Aloha Activism – Aloha Ola O Ka Pono

Puna, Hawaiʻi April 2nd 2026

For decades, those of us born and raised in Puna have lived right next to Israeli Ormat's Puna Geothermal Venture (PGV). We've smelled the rotten-egg odor from hydrogen sulfide (H₂S) releases, dealt with brine aerosols and other emissions listed in PGV's own emergency plans, and watched our families and neighbors struggle with health issues. Many in our community have long suspected these industrial operations contribute to serious sickness, including cancers.

I went looking for real studies on the negative side, as there are many—specifically how toxins from geothermal power plants (like H₂S, arsenic, mercury, radon, and heavy metals in the brine) might be linked to cancer. Here's what the peer-reviewed research from other geothermal areas around the world actually shows, explained in plain English, without any spin about "benefits."

First: What Do Those Numbers (HR, CI, etc.) Actually Mean?

Scientists use special stats to compare groups of people. The key one you'll see is Hazard Ratio (HR). Think of it like this:

●An HR of 1.0 means the chance of getting cancer (or dying from it) is the same in both groups.

●An HR higher than 1.0 (like 1.5) means the exposed group has a higher risk. For example, HR 1.5 means about 50% higher chance compared to the unexposed group.

■The 95% Confidence Interval (CI) is the "range of reasonable doubt." If the CI doesn't cross 1.0 (like 1.2–1.8), the result is usually considered statistically meaningful—not just random chance.

These numbers come from large studies tracking thousands of people over years. They show patterns and associations, and typically when the same patterns keep showing up, they do raise real red flags.

Strongest Evidence: Iceland Studies on Geothermal Water and Emissions

Iceland has used geothermal water extensively for heating homes, showers, laundry, and power—very similar to how emissions and fluids work in places like Puna. Researchers tracked large groups of people using census data and compared those in high-temperature geothermal areas (with more H₂S, radon, and trace metals like arsenic) to people in colder areas with little to no geothermal exposure.

Key findings from these studies (published 2012–2016):

People living in high-geothermal areas had a higher overall chance of cancer. One study found an HR around 1.21–1.22 compared to low-exposure areas—meaning roughly 21–22% higher risk.

Specific cancers stood out with even bigger increases:

Pancreatic cancer: Up to nearly 2–3 times higher risk in some comparisons.

Breast cancer: About 1.5 times higher (and this held for deaths too, not just new cases).

Prostate cancer: About 1.5 times higher, with death rates also elevated.

Kidney cancer: About 1.5 times higher.

Non-Hodgkin's lymphoma (a blood/lymph cancer): Up to 2–3 times higher.

Basal cell carcinoma (a common skin cancer): About 1.6 times higher.

The risk got worse the longer people lived there—showing a "dose-response" pattern (more years of exposure = higher risk). Researchers pointed to ongoing emissions of hydrogen sulfide, radon (a radioactive gas linked to lung cancer), and trace elements like arsenic and mercury in the geothermal water and air.

A follow-up on deaths (mortality) confirmed higher death rates from breast cancer, prostate cancer, and non-Hodgkin's lymphoma among people using the geothermal hot water for daily life.

These aren't tiny studies—they followed tens of thousands of people over decades.

Review of Studies from Italy, New Zealand, and Iceland

A major 2020 review paper looked at 19 different studies from geothermal power and heating areas in Italy (Tuscany plants), New Zealand (Rotorua), and Iceland. It concluded that communities near these operations show increased risk for several types of tumors. Results were mixed (not every study found the same thing), but signals kept appearing for:

Liver, stomach, and lung cancers (especially in some Italian areas with higher plant density).

Respiratory-linked cancers in some data.

The review noted that low levels of H₂S were sometimes linked to higher lung cancer death rates, while very high levels had complicated patterns. Overall, it flagged real concerns for cancer and called for better monitoring and more studies—especially tracking actual toxin levels in people's bodies (biomonitoring--> NEEDED IN PUNA HAWAII NOW!! )

What About Puna Specifically?

The most relevant local document is the 2013 Geothermal Public Health Assessment for Hawaii County. It reviewed complaints, past blowouts (like 1991), and symptoms reported by Puna residents. It found higher rates of respiratory issues, nervous system problems, and other symptoms linked to H₂S peaks and other emissions—but it did not find clear cancer cluster data at that time.

Ashley Kirkawitch, the representative for Puna District 4 on Hawaii Island, continually promises an accurate and up-to-date new health study, but it's all just fabricated for media deception. She was positioned in her role by the geothermal's law firm, Hastings and Pleadwell, and only acts according to her handlers' instructions. We need to demand as a community a new and up to date health study once and for all.

The report highlighted that PGV emissions include known problem substances (H₂S, SO₂, radon, arsenic, mercury, lead, etc.) and said monitoring was inadequate for capturing real community exposures. It strongly recommended proper long-term health studies comparing Puna to similar areas without geothermal operations—studies that still haven't been done comprehensively!!!

PGV's own emergency response plans list the exact brine toxins (including arsenic acid and mercury) that could aerosolize during releases. Natural volcanic activity in Puna adds complexity, but that doesn't erase the added industrial layer from decades of plant operations.

The Bottom Line for Our Community:

Research from various geothermal regions indicates a distinct pattern of elevated cancer risks—particularly for breast, prostate, lymphoma, kidney, pancreatic, and skin cancers—among individuals chronically exposed to similar emissions and fluids. These risks often escalate with prolonged exposure. Many of us have resided near the unmonitored and unregulated geothermal plant in Hawaii for decades, resulting in widespread chronic illnesses. It's time for justice in Puna.

In Puna, we've lived this for 40+ years. We've raised alarms about gas releases, odors, and health effects, only to hear "it's just the volcano." The science from comparable places suggests we deserve real answers: better monitoring of air, water, and soil for these toxins, and independent, community-involved health studies that actually test the cancer hypotheses.

We aren't against clean energy—we want it done without poisoning our ʻohana and ʻāina. It's time for transparent data, real-time public monitoring, and accountability.

If you're in Puna and experiencing health issues, document them and connect with local resources. Share your stories. Raise your voice with KahuPuna. We need comprehensive studies now—not more decades of uncertainty.

Sources for further reading (full papers/reports):

♤ Iceland cancer incidence studies (2012, 2016): Available via PubMed/PMC.

Iceland mortality study (2015).

♧Bustaffa et al. 2020 review: Search "The health of communities living in proximity of geothermal plants" (open PDF versions exist online).

♡2013 Puna Geothermal Public Health Assessment: Available on punageothermalproject.com.

This is based strictly on published research. No hype, no dismissal, no "conspiracy " —just the facts our community needs. People who dont understand might laugh and mock it as not happening, but sadly this doesnt mean it isn't harmful. It's real life for many.

What are your experiexnces? Comment below or reach out. Together, we protect Puna.

Aloha ʻāina forever

#IMUA #AOLEPGV

Jasmine Steiner

KahuPuna Aloha Activism