PFAS and Thyroid Cancer: An Emerging Health Crisis

Among the many health risks and diseases caused by PFAS exposure, thyroid cancer is emerging as a concerning association. Affecting the thyroid gland—a key regulator of metabolism and hormonal balance—thyroid cancer has been on the rise in areas with significant PFAS contamination.

This article explores how PFAS uniquely impacts thyroid health, uncovers its contribution to cancer risk, and identifies strategies for addressing this emerging crisis.

PFAS have a unique affinity for the thyroid gland due to the gland’s reliance on hormonal regulation. Unlike other organs, the thyroid depends on a delicate balance of iodine and hormone production, both of which can be disrupted by PFAS exposure.

PFAS mimic natural hormones and bind to receptors in the thyroid gland, creating imbalances in:

• Thyroxine (T4) and Triiodothyronine (T3): These primary thyroid hormones are disrupted by PFAS, leading to reduced metabolic function, which can impair energy regulation and metabolism across the body.
• Thyroid-Stimulating Hormone (TSH): PFAS interfere with feedback loops, causing the thyroid to overcompensate or underperform, often resulting in conditions like hypothyroidism or hyperthyroidism.

Additionally, PFAS bioaccumulate in thyroid tissues over time, exposing the gland to prolonged oxidative stress. This stress damages cellular DNA, disrupts hormonal production, and fosters an inflammatory environment—conditions that can lead to carcinogenesis. PFAS’ interference with iodine uptake further compromises thyroid function, as iodine is critical for hormone synthesis.

Studies suggest that thyroid cancer cases linked to PFAS exposure may present differently than those caused by genetic or radiation factors. For instance, tumors in exposed populations tend to:

• Exhibit elevated oxidative damage markers compared to non-PFAS-associated cancers.
• Be more resistant to traditional treatments due to the unique molecular changes induced by PFAS.
• Show higher levels of chronic inflammation, which accelerates abnormal cell growth.

Thyroid cancer can be difficult to detect in its early stages. However, some common symptoms to watch for include:

• A lump or swelling in the neck that persists.
• Hoarseness or changes in voice that do not improve.
• Difficulty swallowing or breathing.
• Persistent cough unrelated to respiratory illness.
• Pain or discomfort in the front of the neck.

Early detection is critical for effective treatment. Recommended steps include:

• Thyroid Ultrasound: Imaging tests can detect lumps or abnormalities in the thyroid gland.
• TSH Blood Test: Identifies imbalances in thyroid-stimulating hormone levels.
• Fine Needle Aspiration Biopsy: Used to determine whether thyroid nodules are cancerous.

For military veterans who have served at contaminated bases, it is essential to:

1. Request thyroid-specific screenings, especially if experiencing symptoms or living in a high-risk area (see contamination levels at various military bases).
2. Document symptoms thoroughly and include any relevant service-related exposure evidence when filing claims for VA benefits.

The VA is increasingly recognizing PFAS-related illnesses, and early documentation can improve access to specialized care and disability compensation for veterans.

Thyroid cancer linked to PFAS exposure stands out due to its unique characteristics:

• Gender Disparity: Thyroid cancer cases are disproportionately higher among women exposed to PFAS, reflecting how endocrine-disrupting chemicals interact differently with female hormonal systems.
• Latency Periods: Unlike testicular or kidney cancers, thyroid cancer’s latency period after PFAS exposure can stretch decades, delaying diagnosis and intervention.
• Nonlinear Dose-Response Relationship: Emerging evidence shows that even low levels of PFAS exposure can significantly disrupt thyroid hormones, challenging the notion that only high concentrations are harmful.

While thyroid cancer is rare compared to other cancers, a disturbing trend has emerged in PFAS-affected areas:

• Southeastern U.S. Coastal Regions: Communities reliant on groundwater affected by PFAS-contaminated industrial discharge have reported a disproportionate rise in thyroid abnormalities.
• Remote Military Bases: Remote bases where firefighting foam was used extensively show higher thyroid-related health issues, likely due to prolonged, localized contamination of small water sources.
• Rural Agricultural Communities: PFAS runoff from industrial farming operations has contaminated private wells, exposing populations with limited access to health screenings.

PFAS contamination isn’t limited to industrial or military sites. Research indicates smaller towns and suburban areas using older municipal water systems may unknowingly be at risk due to aging infrastructure that allows PFAS to spread through water supplies.

Recent studies are leveraging molecular biology to:

• Map PFAS Pathways: Researchers are identifying how PFAS bioaccumulates in thyroid tissue, revealing unique molecular fingerprints of PFAS-associated cancers.
• Target Oxidative Stress Mechanisms: Potential treatments aim to reduce oxidative damage at the cellular level, mitigating PFAS-induced carcinogenic effects.

In light of the challenges traditional thyroid cancer treatments face, researchers are exploring precision medicine approaches tailored to the molecular profiles of PFAS-linked cancers. Examples include:

• Gene Editing Techniques: Ongoing research suggests that we may be able to address genetic mutations caused by PFAS.
• Hormone Stabilization Therapies: Other research is looking to rebalance thyroid hormone production that is disrupted by PFAS.

Despite growing evidence, thyroid cancer is often overlooked in PFAS risk assessments. Regulatory agencies typically prioritize cancers like kidney or liver due to their higher prevalence in early studies, leaving thyroid cancer underrepresented in policymaking.

However, current litigation may change this view. As new evidence emerges, the case for holding manufacturers accountable continues to strengthen.

There is an ongoing AFFF mass tort lawsuit that aims to prove the link between PFAS in AFFF and thyroid cancer. Individuals who have been diagnosed with thyroid cancer now or in the past can sign up for representation in this lawsuit.

Those interested in pursuing legal action can visit the AFFF lawsuit registration page for more details.

Grassroots organizations focused on thyroid health and environmental justice are stepping in to:

• Push for thyroid cancer inclusion in PFAS-related legislation.
• Lobby for funding to research long-term PFAS effects on thyroid function.
• Educate policymakers on the importance of early thyroid cancer screenings in PFAS-affected communities.

Individuals in known PFAS hotspots should advocate for regular community-wide thyroid health screenings. Such programs can:

• Identify early markers of thyroid dysfunction.
• Track long-term thyroid health trends in exposed populations.

While systemic change is essential, individuals can take proactive measures to reduce their personal risk:

• Invest in Certified Filters: Ensure your water filtration system is NSF-certified to remove PFAS.
• Switch to Safer Products: Avoid products labeled as water-resistant, grease-proof, or nonstick unless explicitly PFAS-free.
• Monitor Thyroid Health: Regular checkups, including TSH and thyroid ultrasound tests, can catch potential issues early.

PFAS exposure’s role in thyroid cancer is an underexamined but critical public health issue. While the scientific community works to uncover the full scope of this connection, affected individuals and communities must take action to mitigate exposure and demand stronger regulations.

By raising awareness, demanding clean, PFAS-free water, and advocating for better protections in the legal system, we can reduce the impact of PFAS and protect future generations from its harmful effects on thyroid health.