Washington: Smoke emitted by simple wick lamps, used by hundreds of millions of households in developing countries as a dire necessity, is also churning out carbon levels overlooked in greenhouse gas emissions, says a study.
Results from field and lab tests conducted by the universities of California (Berkeley) and Illinois found that seven to nine percent of the kerosene in wick lamps - used to light up 250-300 million households without power - is converted to black carbon when burned.
Conversely, only half percent of the emissions from burning wood is converted to black carbon, the journal Environmental Science and Technology reported.
One kg of black carbon, a by-product of incomplete combustion and an important greenhouse gas, produces as much warming in a month as 700 kg of carbon dioxide does over 100 years, the authors said, according to a California and Berkeley statement.
Factoring in the new study results leads to a 20-fold increase in estimates of black carbon emissions from kerosene-lighting.
The previous estimates come from established databases used by the Intergovernmental Panel on Climate Change and others.
"The orange glow in flames comes from black carbon, so the brighter the glow, the more black carbon is being made," said study principal investigator Tami Bond, associate professor of civil and environmental engineering at the University of Illinois at Urbana-Champaign.
"If it`s not burned away, it goes into the atmosphere."
The findings are surfacing at the same time that the UN Climate Change Conference kicks off in Doha, Qatar.
While officials from around the world are seeking effective policies and guidelines for cutting greenhouse gas emissions, study authors note that the simple act of replacing kerosene lamps could pack a wallop toward that effort.
"There are no magic bullets that will solve all of our greenhouse gas problems, but replacing kerosene lamps is low-hanging fruit, and we don`t have many examples of that in the climate world," said study co-author Kirk Smith, professor at California`s Berkeley School of Public Health.
"There are many inexpensive, cleaner alternatives to kerosene lamps that are available now, and few if any barriers to switching to them," added Smith, also director of the Global Health and Environment Programme.
Smith pointed to lanterns with light-emitting diodes that can be powered by solar cells or even advanced cook-stoves that generate electricity from the heat produced.
Such technology, said Smith, is already available in developing countries.