Motor vehicles are the single largest source of air pollution in Australia, and diesel vehicles are major emitters of air toxins and soot. As Dr. Nic Surawski, a health and environmental equity advocate and environmental scientist, describes the dangerous public health threats of these harmful emissions, nitrogen oxides (NOx), such as nitrogen dioxide (NO2) and nitric oxide (NO), are especially dangerous. In another recent study, 17 of 24 measured diesel vehicles exceeded emissions limits. This problem was widespread across commercial and passenger models alike. This acute injustice should alarm all Australians hoping for real regulation of vehicle emissions. Today, these regulations lag far behind their counterparts in Europe and other parts of the world.
Diesel vehicles make up just one in 10 vehicles on Australian roads. This reality underscores how critical it is to adopt stronger NOx emissions standards. The country has postponed strengthening these regulations, leaving it almost a decade behind European guidelines. With air quality getting worse, advocates and scientists are demanding immediate measures to improve air quality.
Stricter Emissions Standards in Europe
Since 2015, Europe has implemented stricter emissions standards (Euro 5). These regulations as a whole have accomplished a dramatic reduction in NOx emissions from diesel vehicles. The overall cap on NOx emissions from diesel passenger vehicles has been cut nearly in half. It has already plummeted from 180 mg/km to a mere 80 mg/km. In line with the overarching goal of tightening standards, the upper limit for commercial diesels has been lowered from 280 mg/km to 125 mg/km.
Together, these changes are indicative of the real progress we’re making toward protecting public health. We can no longer afford to ignore the disproportionate and dangerous impacts of vehicle emissions. As Dr Surawski observed, “We’ve been stuck with Euro 5 for way too long. The Australian automotive industry needs to pivot toward these developing standards to avoid years more of deleterious health effects from air pollution.
It’s a false statement because new advanced technologies such as Selective Catalytic Reduction—SCR—can cut NOx emissions by as much as 95 percent. Their use is still extremely miniscule for implementation in Australia. This is most commonly seen, for instance, with the 2022 Toyota Land Cruiser Prado, which uses SCR technology while the 2024 Mitsubishi Pajero Sport does not. This disparity highlights the need for regulatory changes to ensure that manufacturers provide vehicles equipped with the latest emission-reducing technologies.
Health Impacts of NOx Emissions
The relationship between NOx emissions and public health is clear-cut. Fay Johnston, an expert in environmental health, stated, “Of all the mix of pollution that comes from cars, NOx has the biggest impact on public health.” Each 1 µg/m3 increase in NOx levels is linked to an increased incidence of serious health conditions such as cardiovascular and respiratory diseases. Experts have estimated that these emissions cause hundreds of premature deaths each year nationally in Australia.
As such, the decision to further delay tightening vehicle NOx pollution regulations represents yet another costly blow to public health. Johnston emphasized, “Motor vehicles are one of the most important sources of air pollution in Australia.” Without strong action to reduce emissions, this present public health calamity stands to get much worse.
AdBlue, which is a common solution already stored in petrol stations across Australia, works in diesel vehicles to reduce harmful NOx emissions. Its success depends on whether or not that technology is adopted and implemented by vehicle manufacturers into the designs of their vehicles. At present, a large number of diesel vehicles on Australian roads are failing to comply with required standards that are designed to protect public health.
The Future of Emissions Regulations
Australia’s automotive industry is at an important crossroads as the debate on vehicle emissions standards heats up. Dr. Surawski foresees future Eurostandard standards—Euro 7—to be the last emissions standard imposed on light vehicles. After that, combustion-engine vehicles will experience outright bans. As the rest of the world gets more serious about regulations, so too should Australia, in order to provide a better, safer, cleaner environment.
Despite potential challenges posed by new regulations, a spokesperson from the Federal Chamber of Automotive Industries stated, “These regulatory changes are not expected to have a significant effect on model availability.” There’s ample evidence to indicate that manufacturers are able to shift their offerings to comply with more stringent standards.
As Dr. Surawski explained, manufacturers are failing to deliver Australian consumers the best available technology under the present system. He noted, “More than anything, the new standards mean manufacturers have to send us the best available technology and that’s not what’s happening at present.”
