How Much Do We Actually Absorb?

The skin is highly permeable under certain conditions. During showering, warm water increases skin permeability, allowing contaminants to penetrate the body.

Additionally, volatile compounds evaporate into the air, where they are inhaled.

• A study on chloroform (a byproduct of chlorination) found that absorption through the skin and inhalation during a 10-minute shower was equivalent to drinking 2 liters of the same water.
• Skin absorption could contribute from 29% to 91% of the total VOC dose, with an average contribution of 64%.
• Research on PFAS showed that smaller "short-chain" compounds were absorbed at even higher rates than their longer-chain counterparts.
• Approximately 56% of chloroform in shower water is released into the air and inhaled
• Machine washing clothes and opening dishwashers after a cycle also led to increased chloroform in indoor air

Common Water Contaminants and Their Effects

1. PFAS (Per- and Polyfluoroalkyl Substances): Recent research has revealed that PFAS, also known as "forever chemicals," can be absorbed through the skin at levels much higher than previously thought. A study using lab-grown tissue resembling human skin found substantial absorption of 15 out of 17 tested PFAS compounds. These chemicals have been linked to serious health issues, including cancer and liver disease.

2. Chlorine and Chloramines: Used as disinfectants, these chemicals can be absorbed through the skin and inhaled as vapor during showers. They can cause skin dryness, irritation, and have been associated with respiratory issues.

3. Volatile Organic Compounds (VOCs): VOCs easily evaporate at room temperature and can be inhaled as steam during hot showers. Some VOCs are known carcinogens and can cause various health problems.

4. Heavy Metals: Metals like lead, mercury, and arsenic can be present in water due to contamination or old plumbing. While skin absorption varies, prolonged exposure can lead to accumulation in the body.

5. Pharmaceuticals and Personal Care Products: Trace amounts of medications and cosmetic ingredients often find their way into our water supply. While individual exposure may be low, the long-term effects of chronic exposure are still being studied.

Absorption Mechanisms

When we shower or bathe, our skin becomes an efficient absorption surface for various contaminants:

1. Increased Permeability: Warm water opens up pores and increases skin permeability, facilitating the absorption of chemicals.
2. Large Exposure Area: Nearly the entire body surface is exposed during bathing, maximizing potential absorption.
3. Extended Contact Time: Longer showers or baths increase the duration of exposure, allowing more time for chemicals to penetrate the skin.

Factors Amplifying Exposure

Several conditions make showering a higher-risk activity for absorbing contaminants:

• Warm Water: Opens skin pores, increasing permeability.
• Body Surface Area: Nearly the entire body is exposed during a shower or bath.
• Steam and Vapor Inhalation: Contaminants evaporate and are inhaled, contributing to overall exposure.
• Extended Contact Time: Longer showers provide more time for toxins to penetrate the skin.

Protecting Yourself

Several steps can help reduce exposure to waterborne contaminants during showering:

1. Install a high-quality shower filter or whole-house filtration system to remove harmful substances
2. Reduce shower time and temperature to minimize exposure
3. Ventilate your bathroom well to reduce inhalation of vaporized contaminants.
4. Monitor water quality by checking Oasis for your city's water quality and the best filters for you