The graph displays the different factors that caused air pollution in the UK from 1990 to 2005.
Overall, air pollution sources had a tendency to decrease throughout the studied period, except for Transport which remained constant. Additionally, whereas Households was the least significant contributor, industry was the main producer of air pollutants.
First, the figure of Total Air Pollutants showed a clear downtrend over the 15-year period, plummeting from about 7 to about 5 million tonnes by 2005. Of all the factors, Industry accounted for approximately 5.5 million tonnes in 1990. However, this figure experienced a significant plunge, especially during 1993 – 1996, in which it decreased by 2 million tonnes, before reaching the bottom at 2 million tonnes around 10 years later.
In comparison, at 1 million tonnes, Households and Transport’s figures were 6 times less than the number of Industry at the beginning of the research. Despite slight fluctuations, Household contributions decreased minimally over time, by nearly 0.8 million tonnes over 15 years. Finally, in contrast to the other factors, the figures of Transport remained constant at about 0.8 million tonnes throughout the studied period.