Month: May 2026

The highest documented residential radon level in the United States was 2,700 pCi/L, measured in 1984 at the Watras home in Boyertown, Pennsylvania. The reading led directly to the EPA’s 4.0 pCi/L action level and the modern radon industry.

Yes, 20 pCi/L is five times the EPA action level and warrants prompt mitigation. Long-term exposure at 20 pCi/L carries a lung cancer risk roughly equivalent to smoking half a pack of cigarettes a day.

Any reading above 4.0 pCi/L is considered too high by the EPA and should be mitigated. Many homeowners and the World Health Organization recommend acting at 2.7 pCi/L. There is no level that is officially safe, just levels that are lower risk.

Yes, though it is uncommon. Levels above 100 pCi/L have been documented in homes built on uranium-rich geology like the Reading Prong, in areas with strong soil gas pressure, or where structural cracks open a direct pathway from soil into the basement.

Radon concentrations can fluctuate significantly within a single day depending on weather, soil moisture, HVAC use, and how the home is sealed. Radon levels are usually highest in winter when homes are closed up. A continuous monitor captures these swings; a single short-term test may not.

There is no level of radon that is technically “safe.” Outdoor air sits around 0.4 pCi/L and represents background exposure. The EPA’s 4.0 pCi/L action level is the practical threshold for mitigation, but lower is always better.

Clean Air Month is observed throughout the entire month of May each year. In 2026, it runs from May 1 through May 31. It is organized by the American Lung Association and has been observed every May since 1972, the year after the original Clean Air Act was passed.

Indoor air quality (IAQ) refers to the air inside and around buildings, especially as it relates to the health and comfort of the people inside. It is measured by the concentration of airborne pollutants, humidity, ventilation, and air circulation. The U.S. EPA classifies poor indoor air quality as one of the top five environmental health risks in the United States.

Yes. According to the U.S. EPA, indoor air is typically 2-5 times more polluted than outdoor air, and occasionally up to 100 times more polluted. Because the average American spends about 90% of their time indoors, indoor air is the air that matters most for daily health.

The six most common and consequential indoor air pollutants in U.S. homes are radon, particulate matter (PM2.5 and PM10), volatile organic compounds (VOCs), mold and biological allergens, carbon monoxide, and nitrogen dioxide from gas appliances. Radon ranks highest in long-term health impact, since it is the leading cause of lung cancer in non-smokers.

Yes. Long-term exposure to poor indoor air quality has been linked to asthma, lung cancer (especially from radon), heart disease, chronic respiratory illness, cognitive decline, and developmental issues in children. Short-term exposure can cause headaches, dizziness, eye and throat irritation, and worsened allergies. The EPA classifies indoor air pollution as one of the top five environmental health risks in the United States.

Slightly. A famous 1989 NASA study showed that certain houseplants can remove small amounts of VOCs from indoor air, but follow-up research has shown the effect in real homes is minimal. Plants are a great addition to a home for many reasons, but they cannot replace ventilation, source control, HEPA filtration, or radon mitigation. They are a supplement, not a strategy.

Lung Cancer Action Week 2026 runs from May 5–11. It is organized by the American Lung Association’s LUNG FORCE program, observed annually in early May. The week is paired with Turquoise Takeover, a month-long awareness campaign that encourages people to wear turquoise and illuminate landmarks turquoise to raise awareness about lung cancer prevention, screening, and research.

Radon is the leading cause of lung cancer in non-smokers in the United States. According to the U.S. EPA, radon, a naturally occurring radioactive gas that rises from soil into homes, is responsible for approximately 21,000 lung cancer deaths each year. Among lung cancer cases in people who have never smoked, radon exposure accounts for the majority of attributable risk.

Yes. Radon is classified as a Group 1 carcinogen by the World Health Organization and the U.S. EPA. When inhaled, radon’s radioactive decay products damage lung tissue at the cellular level, increasing cancer risk over time. The EPA estimates radon causes around 21,000 U.S. lung cancer deaths annually, making it the second leading cause of lung cancer overall, after smoking.

The EPA’s action level is 4.0 picocuries per liter (pCi/L) of indoor air. At or above this level, the EPA recommends mitigation. Between 2.0 and 4.0 pCi/L, the EPA still recommends considering mitigation, because no radon level is technically safe. The average outdoor radon level is 0.4 pCi/L, while the average indoor level in the U.S. is 1.3 pCi/L.

Test your home for radon using a short-term test kit (3-7 days) or a long-term test (90+ days). Short-term kits are available at hardware stores and online for under $30. For a certified, lab-grade reading, especially before a real estate transaction or mitigation system installation, hire a licensed professional radon testing service. The EPA recommends every home be tested regardless of location.

Lung cancer often produces no symptoms in early stages. Warning signs include a persistent cough, chest pain, shortness of breath, coughing up blood, hoarseness, recurring respiratory infections, unexplained weight loss, and unusual fatigue. Symptoms can be subtler in women, who are more likely than men to develop adenocarcinoma. The American Lung Association recommends seeing a doctor about any symptom that lasts more than two weeks.

Drinking Water Week 2026 runs from May 3 through May 9. It is the annual national observance led by the American Water Works Association (AWWA), recognizing the importance of safe, reliable drinking water and the work of water utilities and professionals across North America. The week has been observed since 1988 when Congress passed a joint resolution establishing it.

Tap water in the United States may contain PFAS (“forever chemicals”), lead from old service lines, chlorine and disinfection byproducts, nitrates, and trace amounts of microplastics. Private well water can also contain arsenic, uranium, radon, iron, manganese, and bacteria. The EPA regulates municipal water at the treatment plant, but contamination can also enter through service lines and home plumbing.

U.S. tap water is among the most regulated in the world, and most municipal supplies meet federal safety standards at the treatment plant. However, contamination can occur after treatment through aging service lines, household plumbing, and private wells that aren’t federally regulated. The only way to know what’s actually in your water is to test it at the faucet.

According to EPA monitoring data released in early 2026, approximately 176 million Americans drink tap water with detectable levels of PFAS, the family of synthetic “forever chemicals” that don’t break down in the environment or the human body. The EPA set a national limit of 4 parts per trillion for PFOA and PFOS in 2024, with utility compliance now extended to 2031.

Yes, especially if you have a private well, your home is older than 1986 (potential lead plumbing), or you’ve never had your tap water tested. Public water systems test at the plant, but contamination can enter after that point. A faucet-level test is the only way to know what’s actually coming out of your tap.

Start with your utility’s Consumer Confidence Report (free, sent annually). Look up your area in the EWG Tap Water Database. For specific concerns, professional testing identifies lead, PFAS, bacteria, arsenic, and other contaminants. Protect Environmental and its legacy brands, including Cliff Cummings Water Services in Massachusetts and RAdata in New Jersey, offer full residential water testing.

World Asthma Day 2026 is observed on Tuesday, May 5. Organized annually by the Global Initiative for Asthma (GINA), it raises awareness of asthma worldwide. The 2026 theme is “Access to anti-inflammatory inhalers for everyone with asthma, still an urgent need.” Asthma affects more than 260 million people globally and over 28 million Americans.

The most common indoor asthma triggers are dust mites, mold, pet dander, cockroach allergens, tobacco smoke, particulate matter, and volatile organic compounds (VOCs) from cleaning products, paints, and gas appliances. The U.S. EPA classifies these as the indoor pollutants most likely to cause or worsen asthma symptoms in homes.

Mold can trigger asthma attacks in people who already have asthma, and ongoing exposure can worsen symptoms. Some research also links early childhood mold exposure to a higher risk of developing asthma. Mold thrives where there’s moisture, so controlling humidity, fixing leaks promptly, and addressing water damage are the most effective ways to limit indoor mold.

Yes, humidity can trigger asthma. High humidity, generally above 50%, encourages dust mites and mold, both of which are indoor asthma triggers. Very humid air itself can also feel harder to breathe. Very dry air, below 30%, can irritate airways too. The EPA recommends keeping indoor humidity between 30% and 50% for healthier indoor air.

Air quality is considered bad for asthma when fine particulate matter (PM2.5), ozone, nitrogen dioxide, or known indoor allergens are elevated. Outdoors, AQI readings above 100 typically affect sensitive groups including people with asthma. Indoors, the warning signs are visible mold, persistent dampness, smoke residue, strong chemical odors, and obvious dust accumulation.

Radon is not currently classified as an asthma trigger. Radon is a radioactive gas that rises from soil into homes and is the second leading cause of lung cancer in the United States. So while radon and asthma are separate issues, both fall under the broader category of indoor air quality, and the EPA recommends every home be tested for radon regardless of asthma status.