Nitrous oxide released into the atmosphere by the firm Lonza at its industrial plant in southern Switzerland account for 1% of annual Swiss greenhouse gases, or 600,000 equivalent tonnes of carbon dioxide (CO2), the Federal Office for the Environment reports.
The emissions, which were previously unreported, were discovered by an external firm during checks at the biotech and chemical company’s Visp plant in canton Valais in 2018; the environment office was subsequently informed and later confirmed the data.
In a statement released on Mondayexternal link, Lonza said nitrous oxide, which is a harmless gas waste product released during the production of the vitamin niacin, was first detected in a periodic test when a nitrogen oxide catalyser was changed.
“Chemical analyses can only detect a substance if it is explicitly being tested for. As the emissions do not present a risk to health and are not regulated in the Ordinance on Air Pollution Control, no tests concerning nitrous oxide had previously been conducted in relation to niacin production,” Lonza said.
It stressed that nitrous oxide, a colourless gas more commonly known as laughing gas, does not present a health risk and that there are no legal or regulatory limits regarding handling the substance.
“However, as nitrous oxide contributes to the greenhouse gas effect, it has attracted increasing attention since 2012 following the revision of the CO2 Act,” Lonza said.
Since the beginning of 2020, nitrous oxide emissions are recorded by the Swiss authorities in an official trading registry. As Lonza is listed in the register it must also submit the relevant emission rights or foreign certificates.
To meet its international obligations under the Kyoto Protocol, the treaty that preceded the Paris Agreement, Switzerland committed to cutting its CO2 emissions for the 2013-2020 period by an average of 15.8% compared to the level recorded in 1990.
The 600,000 tonnes of CO2 equivalent emitted by Lonza, previously unaccounted for, thus have a “negative impact on Switzerland attaining its climate objectives”, the environment office said in a statementexternal link.
To ensure Switzerland meets its Kyoto Protocol target, the Climate Cent Foundation will thus acquire foreign certificates for 5 million tonnes of CO2 and transfer them to the Swiss Confederation, the office added.