Traffic congestion is a public health issue. It increases air pollution which is a known cause of asthma, lung cancer and cardiovascular diseases, and in particular creates "hotspots" of low air quality borne by local residents. It increases the risk of traffic accidents through poor driver behaviour and judgement.
One morning last week, I was stuck in a traffic jam several miles long on the A40 outside Oxford, caused by the super-duper high-flow-thru roundabout at Headington being brought to a halt by roadworks eliminating one lane on one exit and a traffic light failing on another!
Those of you who commute to Oxford will pick up my ironic tone: we have had to endure doubling of commuting times & traffic jams for the past 2 years as Oxford has “improved” each roundabout by turn around the ring road!
Philosophical (I wasn’t going anywhere fast), I found myself wishing the clock turned back to a time when most people lived and worked in the same town, and then I moved on to wishing for a reality where “pass me the floo powder and where is the nearest fireplace?”[Harry Potter], or “beam me up scotty!” [Star Trek] were actual options. These options would improve my quality of life, my health, and my climate. And of course everyone else’s.
It was also not lost on me, in that traffic jam, that this month [March 2016] my colleague and I had made Air Pollution the theme for our free electronic public health newsletter (to receive this, sign up here Global Health Knowledge Base).
I had just written a blog on air pollution caused by traffic jams in India, China, and why it’s the particulates, released by soot & fuel, that we measure for air quality & health. In the blog, Air pollution, can we reduce the impact of cars on urban air quality? , I had hoped that emerging economies were going to learn from the mistakes of the UK and other “developed” countries. And there I was in the mistake.
But this blog is not about the traffic jam: its’ what I faced when I finally made it to the roundabout and afterwards. Cyclists, motorcyclists, cars and vans, all determinedly looking forward focussed only on getting from A to B and oblivious to what was left and right. Roadsense was not evident: dodgems was the name of the game.
I & my passenger came so close to be an RTA (road traffic accident) on that roundabout, caught as I was between slamming on my brakes and being rammed from the rear or hit side on. I reached my desk intact because I was experienced enough to realise my only choice was to make it through the gap ahead before it shut.
Knowing that road safety is one of the newly adopted 2030 Agenda for Sustainable Development: “halving the global number of deaths and injuries from road traffic crashes by 2020”, I ran a search on CABI's Global Health database using keyword descriptors for ("road safety" or "traffic accidents" or (safety and traffic), and found 3428 records. I then drilled down for any link to driver behaviour or air quality and selected a couple for you.
Enjoy the further reading I found!
- Global status report on road safety 2015
- Preempt or yield? An analysis of driver's dynamic decision making at unsignalized intersections by classification tree
In China, drivers rarely stop completely at unsignalized intersections, but gradually enter and decide to yield or not by “gaming” with other vehicles. This paper analysed real-life videos to see decisions made by drivers driving straight when faced with merging traffic.
- Health risk assessment of mobility-related air pollution in Ha Noi, Vietnam
Hanoi’s transition from bike to car is rapid: cars increasing at 12%-15% annually. This paper overviews the air quality and pollution caused by road traffic in central Hanoi (5 old districts). It shows that health impact of the shift to motor traffic is primarily one due to air pollution rather than traffic accidents.
- Pedestrian and bicyclist flows in accident modelling at intersections. Influence of the length of observational period [Sweden]
Accident data were compiled and traffic counting was conducted at 113 urban intersections in Sweden. All models showed a safety in numbers effect, including the model for single pedestrian accidents, which might suggest that maintenance and infrastructure quality constitute an important factor for the safety in numbers effect.