Most toxic tort cases have arisen either from exposure to pharmaceutical drugs or occupational exposures. Most pharmaceutical toxic injury cases are mass tort cases, because drugs are consumed by thousands of people, many of whom become ill from a toxic drug. There have also been many occupational toxic tort cases, because industrial and other workers are often chronically exposed to toxic chemicals - more so than consumers and residents. Most of the law in this area arises from asbestos exposure, but thousands of toxic chemicals are used in industry and workers in these areas can experience a variety of toxic injuries. Unlike the general population, which is exposed to trace amounts of thousands of different chemicals in the environment, industrial workers are regularly exposed to much higher levels of chemicals and therefore have a greater risk of developing disease from particular chemical exposures than the general population. The home has recently become the subject of toxic tort litigation, mostly due to mold contamination, but also due to construction materials such as formaldehyde-treated wood and carpet. Toxic tort cases also arise when people are exposed to consumer products such as pesticides and suffer injury. Lastly, people can also be injured from environmental toxins in the air or in drinking water.