What is Vog?
Vog is a term that refers to volcanic smog. It is the haze you see in the air along with invisible gases. Vog is caused by a combination of volcanic activity, weather, and wind conditions.
Vog becomes thicker or lighter depending upon the amount of emissions from Kilauea volcano, wind speed and direction, altitude, temperature, humidity, and other weather conditions.
Volcanic eruptions inject water vapor (H2O), carbon dioxide (CO2), sulfur dioxide (SO2), hydrogen chloride (HCl), hydrogen fluoride (HF), and ash (pulverized rock and pumice) into the atmosphere and stratosphere. The most significant impacts from these injections come from the conversion of sulfur dioxide to sulfuric acid (H2SO4), which condenses rapidly in the stratosphere to form fine sulfate aerosols*.
Vog is comprised of gas and aerosols* of tiny particles and acidic droplets, created when sulfur dioxide (SO2) and other gases emitted from Kilauea Volcano chemically interact with sunlight and atmospheric oxygen, moisture, and dust.
Vog is primarily a volatile gas mixture within 60 miles of the Kilauea's active vents, but as it moves away from the volcano, vog gases attach to moisture and dust particulates creating aerosols* of sulfuric acid and other sulfate compounds and heavy metals including arsenic, mercury selenium, and iridium.
The vog contaminants on the islands of Maui and Oahu are primarily bound to particulates in an aerosol*.
*Aerosols are formed by the conversion of gases to particles and are the combination of small particles in a gas called a suspension. The particles may be solid or liquid or a mixture of both. Dust, smoke, fume, haze, and mist are common terms for aerosols.
How does Vog affect our health?
Disclaimer: I am not a doctor or health professional and I am not giving medical advice. Consult your doctor or health practitioner for medical advice.
Many people feel the immediate effects of vog through reactions such as itchy eyes, runny nose, sore throat, irritability, and tiredness. However, there is limited medical information at this time on the serious long-term health effects of ongoing exposure to vog year after year.
The four things that determine how much vog you are being exposed to and inhaling are density of the vog gases and aerosols in the air, time duration, frequency, and breathing rate. The density, duration, and frequency are largely determined by output intensity of the volcano, proximity to the volcano, wind direction and speed, as well as other weather factors including rain.
Physical complaints associated with vog exposure include headaches, breathing difficulties, increased susceptibility to respiratory ailments, asthma attacks, watery itchy eyes, sore throat, throat infections, flu-like symptoms, runny nose, a general lack of energy, and exhaustion.
There are reports of heart-related problems associated with vog.
The Honolulu Advertiser reports that more than 20 additional people are taken to the emergency rooms with respiratory aliments at Oahu’s hospitals on voggy days. People with pre-existing respiratory conditions are more prone to the adverse effects of vog. Exercise is contraindicated on voggy days.
Sulfur Dioxide (SO2) is a poisonous gas that irritates the skin and the tissues and mucous membranes of the eyes, nose, and throat. During even moderate physical activity, SO2 penetrates deeply into the airway and can produce respiratory distress in some individuals. In the absence of strong winds, SO2 emitted by Kilauea can accumulate in the air and reach levels that exceed Federal health standards.
Because of their small size, aerosol particles such as those in vog penetrate deep into the human lung and are readily retained. Studies of air pollution in the United States, Japan, and elsewhere indicate that elevated levels of acidic particles like those in vog can induce asthma attacks, especially in adolescents, and can also impede the ability of the upper respiratory tract to remove other potentially harmful particles. The unique combination of acidic particles, toxic metals, and SO2 gas in vog may account for the wide variety of physical symptoms reported.
Note on plants and water catchment systems: tiny droplets of sulfuric acid in vog create acid rain which is seen to wither and yellow plants even on outer islands and to kill entire farm crops on the Big Island. This acid rain also leeches lead and other metals from roofing and plumbing materials, such as nails, paint, solder, and metal flashings. Leeched lead poses a health hazard when it contaminates drinking water in rainwater-catchment systems.