Palladium Is An Unsung Green Superhero

 | Oct 13, 2019 04:32AM ET

Smog from vehicle emissions is estimated to cause a third of the air pollution in the United States. The fact that cars and trucks have tailpipes at street level makes the exhaust fumes even more harmful than industrial smokestacks, because people breathe them directly into their lungs.

Despite greater environmental awareness and transit use, vehicles continue to emit a toxic cloud of four air pollutants, caused by the burning of gasoline in the internal combustion engine. They are:

  • Carbon monoxide, expelled when the carbon in fuel doesn’t burn completely. Breathing CO is particularly harmful because it impairs the ability to move oxygen through the body;
  • Hydrocarbons, a compound of hydrogen and carbon;
  • Nitrous oxides, a product of burnt fuel, created when nitrogen reacts with oxygen;
  • Particulate matter, which consists of tiny soot particles that contribute to hazy skies and, when inhaled on a regular basis, can cause lung damage.
  • Other health problems known to result from air pollution include asthma, heart disease, birth defects and eye irritation.

    A study earlier this year found over 30,000 Americans had died from diseases connected to air pollution in 2015, the latest year data was available.

    According to Environmental Defense Fund, the transportation sector is responsible for 27% of the country’s greenhouse gas emissions. Passenger vehicles produce four times more greenhouse gases than all of domestic aviation.

    In 2018 there were 276 million vehicles registered in the US, 40% of which were cars. In 1990 just under 200 million were registered. The sheer number of people that continue to drive and buy cars has offset pollution-control measures adopted by the auto industry, along with the growing popularity of hybrid-electric vehicles, electric vehicles and renewable fuels - ethanol and biodiesel.