McNoe and colleagues1 are to be commended for making the effort that was required to identify and enumerate work-related traffic deaths. That it should take such an effort and yield data that is still incomplete is a clear signal that we need to modify the way that such information is routinely recorded. As the authors point out, surveillance that would identify important trends in these events, such as changes due to the casualisation of labour, requires data to be accessible in a timely fashion.

By including traffic fatalities occurring while commuting, as well as in the course of work, the authors make a significant statement recognising the joint responsibility of employers and employees for the trip to work. This is an important step towards reducing such deaths. The location of workplaces relative to where employees live and the times of day employees are required to travel are seldom controlled by the employees themselves, and this is particularly so for the least well off. These can be important determinants of the risk of traffic injury.

McNoe has shown that commuting deaths are a significant fraction of all work-related injury deaths. Traffic-related deaths make up the largest group of work-related deaths (about 30%), and of these 44% occur while commuting.1 Deaths of commuters are the events most likely to have been underestimated, since the reason for the trip is poorly reported in available records. The Auckland Car Crash Injury Study2 recorded this information for all drivers in serious crashes in 1998–9 in the Auckland region. We found that 15% of drivers in crashes that resulted in hospitalisation or death were commuting, and another 5% were working at the time (unpublished data). Work-related injury prevention needs to extend its reach to the issue of commuting if this level of injury is going to be appreciably reduced.

Of course there are other hazards of driving to work, especially in situations where commuters spend long periods of time in their cars every day and where congestion is a problem. In comparison with more active modes of transport (public transport, cycling and walking), commuting by car can result in a chronic reduction in physical activity, deterioration in air quality for the whole community, and significant stress for some. The relationships between low levels of exercise and obesity, diabetes, and coronary heart disease are well known and are generating considerable concern. The health effects of traffic-related air pollution have also been estimated in New Zealand and account for more deaths than traffic crashes in Aucklanders over 30 years of age.3 While the current urban environment requires car ownership to access many vital social services, the severance effects of heavy traffic on neighbourhoods, and the isolative nature of car commuting result in a reduction in social connectedness for many.

However, any significant change to the mode of travel to work will require organisational support and changes in environmental infrastructure as well as a greater awareness of the benefits. Apart from improving the quality and quantity of public transport and better provision for pedestrians and cyclists on the roads, a promising approach is the development of organisational travel plans.4 These plans aim to reduce single occupant car commuting through a variety of workplace interventions, including promotion of walking and cycling, improved organisational infrastructure for cyclists, financial assistance for public transport, and disincentives for car users.

Two complementary approaches to reducing the hazards of driving to work are needed. One is to address the issues relevant to commuting by car to and from each specific workplace, as part of work-related injury prevention. An example of this would be eliminating the need for staff to drive home in the early hours of the morning by changing shift times or providing alternative transport. The longer term, more sustainable, public health approach is to change the way people travel to and from work. This would both reduce the exposure to health risks such as the commuter traffic injury described by McNoe, and bring other health benefits to the individuals and their communities.

Author information: Jennie Connor, Senior Lecturer; Alexandra Macmillan, Lecturer; Section of Epidemiology and Biostatistics, School of Population Health, University of Auckland, Auckland

Correspondence: Dr Jennie Connor, Section of Epidemiology and Biostatistics, School of Population Health, University of Auckland, Private Bag 92019, Auckland. Email: j.connor@auckland.ac.nz