Important factors with an impact on health

Air Pollution

In the UK motor vehicles are responsible for 46-61% of nitrogen dioxide in outside air, and up to 25% of particulate emissions (such as PM10). Traffic related air pollution is associated with rises in deaths and hospital admissions. Transport accounts for over 25% of the UK's emissions of carbon dioxide, thus contributing to global warming and climate change.

Road traffic injuries

Transport accounts for over a third of 'accidental' deaths in the UK, with rates of injury to pedestrians and cyclists higher in the UK than in most Western countries. The danger posed by traffic increases with increasing speed; at normal urban speeds each 1 mph increase in speed increases the likelihood of death or serious injury by 5%. It should be noted that the 30mph speed limit in urban areas is an arbitrary threshold, and this speed may well be excessive in many situations. Around 70% of motorists habitually break the 30mph urban speed limit.
Perceived danger from traffic leads to restrictions on children's independent mobility, and increases the likelihood that they will be transported by motor vehicle, thus increasing traffic and creating a vicious circle.

It is important to bear in mind that, despite their wide currency as indicators of the safety or danger of a road, injury or 'accident' data are an extremely poor measure of the level of danger, as the natural tendency is for people to withdraw from threats, for example by avoiding cycling along, or crossing, busy roads: this is known as risk compensation. As an illustration of this it is worth noting that pedestrian casualty rates are extremely low on both pedestrian precincts and motorways, but these locations pose very different levels of danger.

Health effects: Definite and significant but unquantifiable (due to risk compensation)

Physical activity

Lack of physical activity is a major public health problem - it has been estimated that 12% of deaths in the US are attributable to sedentary lifestyle - and both adults and children , in the UK are less active, less fit, and more likely to be obese as a result of inactivity than previously. Physical activity, such as walking or cycling to school or work, reduces the risk of heart disease, stroke, , diabetes, , obesity, high blood pressure, , depression, cancer (especially of the large bowel ), and osteoporosis, and improves one's sense of well-being.

Walking is an important mode of transport within a small town such as Woodstock, and is an ideal form of exercise for many people as it can be incorporated into the daily routine, but the needs of pedestrians are often ill met (the recent House of Commons Environment, Transport and Regional Affairs Select Committee report on Walking in Towns and Cities provides an excellent discussion of this issue, and is recommended reading for anyone concerned with improving the quality of the urban environment to provide health, social and other benefits).

Health effects: Definite and significant, and in some cases estimable

Community severance

When a large or busy road passes through a community it may prevent safe and easy access to shops, schools and other facilities for local residents. It may also affect social networks; the number and frequency of social contacts falls as traffic levels increase. People without good social support have increased mortality rates, and traffic reduces the use of residential streets as play areas for children.

Health effects: Speculative

Noise

Transport is the most pervasive source of noise in the UK daily environment, and noise pollution contributes to stress-related health problems such as high blood pressure, minor psychiatric illness, sleep loss and other health effects. Most traffic noise in urban areas is a result of engine and transmission noise, but at night events such as car stereos, slamming doors, and starting engines can be a major irritant. Above about 50mph tyre noise is the main source.

Health effects: Definite but unquantifiable

Access/mobility

Access to education, work, shops, healthcare, leisure activities and social networks often requires transport. Those without the use of a car have reduced access to facilities which have been designed with an assumption of car use, such as out of town supermarkets or leisure facilities. Even in car owning households the elderly, women, and children are less likely to have access to car use than other groups, and those with disabilities are especially disadvantaged.

Health effects: Definite but unquantifiable

Health inequalities

Pedestrians and cyclists are more likely than drivers to suffer traffic injuries per distance travelled. There is a marked social class gradient for traffic injuries, with children from poorer families five times more likely to be killed on the road than those from other families. , House prices and rents are usually lower close to busy roads; air and noise pollution and community severance are experienced disproportionately by those who cannot afford to live in more amenable surroundings.

Many of the diseases to which a lack of physical activity predisposes are associated with deprivation, and there is a marked social class gradient for physical activity in leisure time.

Health effects: Definite but unquantifiable