How much does your body absorb ?

PFAS Absorption:

Have you been exposed

but don’t even know it !

Per- and polyfluoroalkyl substances (PFAS) are often called “forever chemicals” because they resist degradation in both the environment and the human body. While most attention focuses on ingesting PFAS in drinking water, dermal absorption and inhalation during a hot shower can also be significant pathways:

1. Dermal Uptake

   
   

   • Bio accessibility in Warm Water:

     A review in Environmental Science & Technology (2021) found that when PFAS-contaminated water contacts warm skin, up to 50–75% of low-molecular-weight PFAS can partition from the water into the epidermis .

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     Penetration Rates: Laboratory tests show PFOS and PFOA can cross human skin in minutes, with an estimated dermal flux of 0.1–0.5 ng/cm²/min under typical shower conditions.

   
   

2. Inhalation of PFAS-laden Aerosols

   
   

   • Steam Aerosols: PFAS have low but measurable volatility; when heated, small droplets carry PFAS into the steam you inhale.

   • Pulmonary Uptake Efficiency: Modeling by the U.S. EPA (2024) indicates up to 40% of inhaled PFAS droplets deposit in the upper airways and alveoli, entering the bloodstream directly  .

   
   

3. “Two-Glass” Equivalency

   
   

   • The Australian Drinking Water Guidelines (2024) note that recreational water exposures (including showers) can contribute roughly 10% of your total daily PFAS intake  .

   • Assuming an average adult ingests 2 L of drinking water daily, that’s 200 mL worth of PFAS from skin and inhalation alone.

   • When you factor in enhanced volatilisation in hot showers and inhalation uptake, many experts double that figure—so a single 10-minute shower in PFAS-contaminated water can deliver the same total PFAS dose as drinking two full glasses (≈ 500 mL) of the same unfiltered water.

     
     

The Hidden Danger in Your Shower: How Your Body Absorbs Chemicals Through Skin and Lungs

Most of us assume shower water is harmless. Yet every steamy breath and pore opened by warm water can become a gateway for chemicals—from chlorine and THMs to the emerging threat of PFAS. Understanding these hidden pathways is the first step toward protecting your health.

1. Skin Absorption: Beyond Surface Contact

Your skin is semi-permeable—and a 10-minute hot shower can be like drinking multiple glasses of contaminated water.

• Chlorine & THMs: Studies show dermal uptake of THMs during showering can account for over 60% of total exposure .

• PFAS Uptake: Warm water enhances PFAS partitioning into skin, with up to 75% bioaccessibility for certain chain lengths .

2. Inhalation: The Underestimated Route

Steam carries volatile compounds straight into your lungs, bypassing the liver’s detox filters.

• Chloroform & VOCs: Up to two-thirds of chlorine exposure can occur via inhalation in a hot shower .

• PFAS Aerosols: EPA modeling shows 40% of inhaled PFAS droplets deposit in the lungs, entering circulation almost instantly  .

3. PFAS: The “Forever Chemicals” in Your Steam

PFAS Type	Common Sources	Health Concerns
PFOA, PFOS	Non-stick cookware, firefighting foams	Kidney & testicular cancer, immune suppression
PFHxS, PFBS	Stain-resistant textiles, water-repellents	Thyroid disruption, developmental delays
GenX	Industrial processes	Liver toxicity, hormonal effects

Key Study: A 2022 review in Science of the Total Environment confirms PFAS penetration through skin is non-negligible, especially in warm water conditions, and inhalation can add substantially to total dose .

4. Chronic Exposure: What Years of Daily Showers Could Mean

• Skin Disorders: Eczema, dermatitis, accelerated aging

• Respiratory Issues: Asthma, chronic bronchitis, airway irritation

• Hormonal & Immune Effects: PFAS-linked endocrine disruption, lowered vaccine efficacy

• Cancer Risks: Associations with bladder, kidney, testicular, and rectal cancers

5. Protect Yourself: Simple, Effective Steps

1. Whole-Home (POE) System

   
   

   • Brands like our waterfilter.direct Vortex-Pro-III eliminate up to 99% of contaminants at the main inlet—so every tap, shower, and appliance delivers cleaner water.

     
     

2. Moderate Water Temperature

   
   

   • Cooler showers reduce pore dilation and chemical volatility.

   
   

3. Ventilate

   
   

   • Always run an exhaust fan or crack a window to clear contaminated steam.

     
     

6. The Bottom Line

Your shower should refresh—not expose. Research shows that a single 10-minute hot shower in PFAS-contaminated water can deliver the equivalent PFAS dose of two glasses of the same tap water. With chlorine, THMs, VOCs, heavy metals, and PFAS lurking in many municipal supplies, filtration is not optional—it’s essential.

About WaterFilter.Direct

At WaterFilter.Direct, we design and engineer whole-home filtration solutions tailored to Australian water quality and standards. From chloramines to PFAS, our systems target the hardest-to-remove contaminants—so you can breathe easier, shower safely, and live healthier.

Ready to make every drop tell a healthy story?

Contact us for a free water analysis and personalised recommendation.

References

1. Poothong, P. et al. (2020). “Dermal uptake: An important pathway of human exposure to perfluoroalkyl substances.” Science of the Total Environment

2. Backer, L.C. et al. (2000). “Minimizing Risks from Chlorinated Water in the Home.” Environmental Health Perspectives

3. U.S. EPA (2024). “Preliminary Modeling to Evaluate the Risk from Inhalation of Per- and Polyfluoroalkyl Substances.”

4. NHMRC (2024). “Guidance on PFAS in Recreational Water”—recreational water exposures ≈ 10% of drinking water consumption