A factory at the Chemelot industrial complex in Limburg has been pumping out nitrous oxide, or laughing gas, for decades without the greenhouse gas emissions being officially measured, the NRC has found.

Chemelot is home to two other factories which produce the gas but the existence of a third factory was not noticed until 2017, the paper said.

As a greenhouse gas, N2O is 265 times stronger than CO2. The emissions from the factory, which makes a plastic component called acrylonotril, increases the total of laughing gas emissions from the complex by 50%.

According to the government health and safety board RIVM, Chemelot should have registered the emissions but did not do so until 2017 when it told the provincial authorities of the omission.

The RIVM has now upped its official estimates of greenhouse gas emissions in the Netherlands dating back to 1990. Chemelot told the paper that a technical solution for the emissions, which do not have a legal limit, will cost around €100m.

The situation has been brought to the attention of the ministry of economic affairs and climate and may be discussed at next month’s presentation of the cabinet’s new climate measures, the NRC said.