Increased use of pharmaceuticals spiked carbon emissions during the COVID-19 pandemic despite carbon footprint reduction efforts, new research has revealed.

A group of researchers measuring carbon emissions in a large university hospital with a research centre in central Japan found that its overall carbon footprint increased over a decade. However, they also found that carbon emissions from gas and electricity decreased during the COVID-19 pandemic.

"It is urgent to assess the reality of medical carbon emissions because medical staff cannot sacrifice future generations using the excuse of saving present patients," said Takanori Yamamoto from Nagoya University Graduate School of Medicine.

"It is also important to promote public health measures to reduce future medical demands because the world is facing an ageing society, overtreatment, overdiagnosis and unnecessary visits to hospitals," Yamamoto said in the study published in the journal Globalisation and Health.

The research team found that the overall carbon footprint in 2020 had increased by almost 27 per cent over 10 years. Approximately one-quarter of these carbon emissions came from electricity consumption.

Despite an overall increase in the Nagoya University Hospital's carbon footprint during the study, it decreased slightly, by just over 2 per cent, in the first year of the pandemic.

This was in part due to the lower number of patients in 2020 and the resulting reductions in pharmaceuticals, water usage, and nonmedical waste. However, despite a decrease in the hospital's overall carbon footprint, the severity of COVID-19 still contributed to carbon emissions.

During the pandemic, the average hospital stay of a patient was longer due to the need for greater medical care. Furthermore, the higher number of patients requiring intensive care meant an increase in carbon emissions from pharmaceuticals, the study found.

"It is crucial to recognise the importance of vaccination and preventive medicine from a sustainable perspective," said the researchers.