Why in news?
Recent findings from researchers at the Centre for Atmospheric Sciences at the Indian Institute of Technology (IIT), Delhi on the efficacy of a specific air purifier technology have revealed more about a class of pollutants known as polycyclic aromatic hydrocarbons, or PAHs.
- Polycyclic aromatic hydrocarbons can associate with other particulate matter, like PM2.5, PM10, and make them more toxic
- Particulate matter in the ambient air consists mainly of PM 2.5 and PM 10 particles—tiny atmospheric particles that have a diameter of less than 2.5 and 10 micrometers, respectively.
- PAHs are a class of chemicals and compounds that also contribute to air pollution. While PAHs occur naturally in items like crude, coal and gasoline, they can be produced by a variety of anthropogenic activities—like the burning of coal, oil, gas, wood, tobacco, garbage—including the incomplete combustion of organic matter.
- Forest fires and volcanic eruptions, also contribute to PAHs in the ambient air.
- When inhaled through particulates, PAHs can cause serious health risks—starting from irritation in the eyes and respiratory passages.
- US Environmental Protection Agency (EPA) and the International Agency for Research on Cancer have classified some PAHs as carcinogenic
- In Delhi, the agency found PAHs like fluoranthene, chrysene and dibenz(a,h)anthracene, the latter two are classified as “probable carcinogens” by the EPA
- Plasmacluster ion (PCI) technology releases both positive and negative ions simultaneously into the air; these then recombine on the surface of pollutants floating in the air to create hydroxyl radicals, a type of oxidizing agent