An advisory panel to the Ministry of International Trade and Industry has announced that emissions of greenhouse gases such as hydrofluorocarbons and perfluorocarbons have yet to decrease in some areas.

The ministry’s Chemical Product Council received a report on Tuesday stating that overall emissions of gases, including HFCs and PFCs, which were developed as alternatives to ozone-depleting chlorofluorocarbons, are declining, but that the amount of gases used in producing liquid crystal displays and sprays to dust computers has increased.

The panel heard from industries on voluntary efforts to reduce three greenhouse gases — HFCs, PFCs and sulfur hexafluoride (SF6).

HFCs are used in refrigerators and air conditioners, and are included in dusting sprays. PFCs are used to clean electronic parts and in the production of semiconductors and LCDs. SF6 is used for insulators at substations.

Total emissions of these three gases amounted to 38.7 million tons in 1999, down from 48.5 million tons in 1995. The decline reflects falls in the use of PFCs to wash electronic parts and the use of SF6, due to industry efforts to reduce the emissions and promote alternatives.

However, demand for PFCs used in the production of LCDs has risen rapidly, registering a 4.6-fold increase in emissions between 1995 and 1999.

In addition, emissions of HFC23, a byproduct in the manufacture of fluorocarbon polymers used to cover frying pans, have increased. HFC23 is more than 10,000 times more damaging than carbon dioxide.

There are almost no emissions from HFCs used in refrigerators and air conditioners, but emissions used in sprays to dust personal computers have doubled since 1995.

Some members of the council said it is necessary to strengthen measures to reduce greenhouse gases at an early date, as the production of LCDs is expected to rise in the future.

Greenhouse gases trap heat in the Earth’s atmosphere, causing a rise in temperature. This results in global warming that could cause drought and a rise in sea levels, endangering low-lying countries.

Japan is legally obliged to cut greenhouse gas emissions by 6 percent from 1990 levels by 2008 and 2012, according to the 1997 Kyoto Protocol on curbing global warming.