More effective central and local government with the necessary power to pass and enforce laws led to a range of improvements in public health and the quality of the environment. These included improvements in housing, better ventilated and less overcrowded accommodation, clean drinking water, laws to combat the adulteration of food and drink, the pasteurisation of milk, and improved waste disposal methods. Similarly, the Clean Air Act reduced pollution, such as the smog that led to 4,000 deaths in London in 1952.