A comparison of the carbon footprint of alternative sampling approaches for cervical screening in the UK: A descriptive study.

OBJECTIVE

To understand whether self-sampling can reduce carbon emissions (CO2 e) from the NHS cervical screening programme (NHSCSP) by comparing the carbon footprint of three sampling strategies: routine cervical sampling, vaginal self-sampling and first-void (FV) urine collection.

DESIGN

Descriptive study.

SETTING

National Health Service (NHS), United Kingdom (UK).

POPULATION OR SAMPLE: Patients aged 25-64 years eligible for cervical screening in the UK.

METHODS

A carbon footprint analysis was undertaken for three cervical screening sampling approaches, from point of invitation to screening through to preparation for transport to the laboratory for HPV testing. A combination of primary and secondary data were used, with a bottom-up approach applied to collection of primary data.

MAIN OUTCOME MEASURES: We report CO2 e per sampling approach, which is the unit used to express carbon footprint and harmonise the contributions of greenhouse gases with different global warming potentials.

RESULTS

The total carbon footprint of routine cervical sampling is 3670 g CO2 e. By comparison, vaginal self-sampling had a total carbon footprint of 423 g CO2 e, and FV urine sampling 570 g CO2 e. The largest share of emissions for routine sampling was attributable to the carbon footprint associated with an appointment in a primary care setting, which totalled 2768 g CO2 e.

CONCLUSIONS

Routine cervical sampling is up to 8.7-fold more carbon-intensive than self-sampling approaches with equivalent effectiveness. We found negligible differences in the carbon footprint of alternative self-sampling methods, supporting the need for an informed choice of screening options for participants, which includes sharing information on their environmental impacts.