Increased emissions of hazardous substances to air
Nature and the environment
milgiftn, Emissions to air of hazardous substances and particulate matter, air pollution, hazardous substances (for example lead, copper, mercury), particulate matter, emissions by industry (for example energy sector, manufacturing, primary industries)Pollution and climate, Nature and the environment

Emissions to air of hazardous substances and particulate matter1990-2010



This is an archived release.

Go to latest release

Increased emissions of hazardous substances to air

The emissions to air of several hazardous substances increased in 2010. The increase was partly due to higher activity in parts of industry.

The emissions of arsenic, some heavy metals, particulate matter and dioxins to air have increased in 2010. The increase was due to increased activity in parts of industry, and a higher content of contaminants in raw materials and reducing agents used in metal production. The emissions to air of several hazardous substances including PAHs (polycyclic aromatic hydrocarbons) have been considerably reduced since 1990.

The calculations of emissions to air for the period 1990-2010 are performed by Statistics Norway in collaboration with the Climate and Pollution Agency.

Emissions of heavy metals, PAH-4 and dioxins. Per cent change 1990-2010 and 2009-2010 and harmful effects
  Unit 2010 Per cent change 1990-2010 Per cent change 2009-2010 Harmful effects
Lead kg 5 654 -97 3    Dangerous ecological toxin. No damage to health at concentrations currently found in air in Norway, but accumulates in living organisms, so that formerly high emissions still constitute a health hazard.
Cadmium kg  590 -50 22    Liable to bioaccumulate. Delayed effects such as pulmonary emphysema, cancer, reduced fertility in men and kidney damage.
Mercury kg  584 -60 13    Becomes concentrated in organisms and food chains Causes kidney damage and harms nervous system. May cause cellular changes.
Arsenic kg 1 819 -48 43    Inorganic arsenic compounds (arsenates) very toxic to most organisms (acute and chronic effects), carcinogenic even at low concentrations. Organic compounds are much less toxic.
Chromium kg 2 945 -77 3    Liable to bioaccumulate. Hexavalent compounds (Cr6+) are carcinogenic and sensitising. May cause kidney and liver damage.
Copper kg 26 211 2 3    Liable to bioaccumulate. Some copper compounds are acutely toxic or irritant to mammals.
PAH-41 kg 8 578 -77 -6    Several are carcinogenic.
Dioxins g 26 -80 19    Become concentrated in organisms and food chains. Carcinogenic.
PM1 0 tonnes 53 863 -20 7    Increase the risk of respiratory complaints.
1  Polycyclic aromatic hydrocarbons (PAHs) consist of fused aromatic rings. Norway has an obligation to report emissions of PAHs to the Convention on Long-Range Transboundary Air Pollution (CLRTAP) For the purposes of emission inventories, the following four indicator compounds shall be used: benzo(a)pyrene,benzo(b)fluoranthene, benzo(k)fluoranthene, and indeno(1,2,3-cd)pyrene.
Source:  Emission inventory from Statistics Norway and the Climate and Pollution Agency.

Increased emissions of mercury, cadmium and arsenic

Emissions of mercury, cadmium and arsenic have increased by 13, 22 and 43 per cent respectively since 2009. Emissions from manufacturing industries and mining accounted for more than 70 per cent of the increase for all three components.

Emissions of mercury were 0.6 tonnes in 2010, which is a 13 per cent increase since 2009. The main reason for the increase is higher process emissions from production of cement and iron, steel and ferroalloys. The most important source of mercury emissions is combustion without energy utility, which comprises cremations. The emissions have been considerably reduced since 1990, and have been relatively stable since 2000.


Emissions to air of cadmium totalled 0.6 tonnes in 2010. Wood-burning in private households and burning of refuse wood and waste liquor in the wood processing industry are the most important sources of emissions of cadmium to air. In 2010, these sources contributed with 25 cent of the total emissions each. Cadmium emissions have been reduced by 50 per cent since 1990, and the main reason for this is reduced emissions from production of iron, steel and ferroalloys due to emission reduction efforts and the closing down of production plants. This source was responsible for 7 per cent of cadmium emissions in 2010, compared with 26 per cent in 1990.


In 2010, 1.8 tonnes of arsenic were emitted to air. For the past few years, the variation in arsenic emissions has been due to varying arsenic content in raw materials and reducing agents used in metal production. The total arsenic emissions have been reduced by 48 per cent since 1990.

Emissions of lead, copper and chromium are stable

Emissions of lead and copper have been relatively constant in recent years. Emissions from brake wear is the dominant source for emissions to air of lead and copper. Combustion in the wood processing industry is the most dominant source of chromium emissions to air.

Change in emissions to air of hazardous substances. 1990-2010. Index 1990=1

Increased emissions of dioxin

In 2010, 26 grams of dioxins were emitted to air. Since 2009, emissions of dioxin have risen by 19 per cent. The emissions have been reduced by 80 per cent since 1990. A large proportion of this reduction is due to the shutting down of one industrial plant and one mine. In addition, emissions from energy supply were reduced by 95 per cent from 1990 to 2010 due to the introduction of cleaning measures at waste incineration plants. Since 2005, the emissions have been relatively stable. The most important emission source in 2010 was wood-burning in private households. Calculated emissions from house fires have increased by about 50 per cent from 2009 to 2010. This is not a real increase, but an increase due to the inclusion of chimney fires in the basic data since 2010. Combustion emissions from navigation and process emissions from metal production accounted for 17 and 10 per cent of the total respectively.

Emissions of particulate matter increased by 7 per cent

Emissions of particulate matter (PM1 0) were 53 900 tonnes1 in 2010, which is a 7 per cent increase since 2009. Sixty-two per cent, or about 33 000 tonnes, of the emissions of particulate matter (PM1 0) in 2010 came from wood-burning . The wood consumption rose by 11 per cent from 2009 to 2010. At the same time, the calculated emissions of particulate matter from this source rose by only 8 per cent. This is due to a higher share of wood stoves with new technology. Process emissions from manufacturing and mining amounted to 7 500 tonnes, or 14 per cent of the emissions of particulate matter in 2010. Motorized equipment and road dust/tyre wear were responsible for 5 and 3 per cent of the emissions respectively.

PAH-4 emissions are still decreasing

Process emissions in aluminium production are the most dominant source for PAH-4 emissions, and contributed with 51 per cent of the total PAH-4 emissions to air in 2010. The figures for 1990 and 2009 were 84 and 58 per cent respectively. The PAH-4 emissions decreased primarily because of the discontinuation of Soederberg technology in the aluminium production. Wood-burning contributed to 25 per cent of the emissions in 2010, compared with 7 and 22 per cent in 1990 and 2009 respectively. Road traffic contributed to 16 per cent of the emissions in 2010. This includes both exhaust and tyre and brake wear.

The time series for PAH emissions from aluminium production have been recalculated for the period 2005 to 2009. The new calculation method, which has been used for all years, includes both particular PAHs and PAHs in gas phase, causing higher emissions for the years since 2005 than earlier calculated. There are, however, large annual fluctuations in these calculated emissions. The long-term trend shows a decline.

Change in emissions to air of PAH-4, particulate matter (PM10) and dioxins. 1990-2010. Index 1990 = 1

Reduction in most emissions after 1990

Norway has a national target to reduce emissions compared with the emission levels in 1995. Internationally, we have an obligation to reduce emissions of selected hazardous substances compared with 1990. Emissions of PAH-4 have been reduced by three quarters since then, mainly due to reduced emissions from aluminium production. There has also been a positive trend in emissions of other hazardous substances, except for copper emissions, which are at the same level as in 1990.

The cause of the decrease since 1990 is primarily reduced emissions within manufacturing and mining. Cleaning measures, changes in production procedures and lower activity in some industries have all resulted in reduced emissions. Due to the phasing out of lead-containing petrol, the emissions of lead from road traffic fell dramatically from 1990 to 1996. Fluctuations in emission levels can be affected by uncertainty in measurements.

Differences between emissions to air and local air quality

Particulate matter in air contributes to poor air quality locally, but can also be transported over great distances. The figures calculated in these statistics are emissions to air, i.e. the amount of particulate matter coming from the chimney, exhaust pipe etc. This is not to be confused with local air quality or concentrations, which is the amount of substance that is actually breathed by humans. In concentration calculations, the fact that humans are more exposed to some emission sources than others is taken into account. For instance, emissions from wood-burning are often emitted from chimneys, and do not affect local air quality to the same extent as exhaust emissions. For this reason, one tonne of particulate matter from wood-burning is less significant to concentrations at ground level than one tonne from exhaust.


The health risks associated with local air pollution depend on how high the concentration of the polluting substance is, and on length of exposure. Asthmatics and people with respiratory disorders or cardiovascular diseases are most heavily affected by air pollution in Norway. In addition, children and young people, pregnant women and the elderly are especially sensitive.

About the emission inventory

All emission estimates are burdened with some uncertainty. Due to measuring uncertainty in data reported to the Climate and Pollution Agency, the uncertainty is particularly high for reported emissions from parts of the industry. This is partly due to low levels of hazardous substances, which makes accurate measurements challenging. In addition, frequent measurements are essential to obtain good estimates when emissions vary with time, and the measurements should often be performed more frequently than what is practically and economically feasible.

For more information about the emission calculations, see The Norwegian Emission Inventory 2011. Documentation of methodologies for estimating emissions of greenhouse gases and long-range transboundary air pollutants (Documents 21/2011)

Read more about emissions of acidifying substances . Revised emission figures for greenhouse gases will be published on 13 February 2012.