More than 20 years on from the 9/11 terrorist attack on New York’s World Trade Centre, the exposure of an estimated 500,000 people to the toxic cloud of dust and ash is under the microscope as legacy diseases begin to make themselves apparent.
The dust that resulted from the falling buildings consisted of cement dust and particles, persistent organic pollutants including dioxins and hydrocarbons, and asbestos.
The dust also contained heavy metals, including lead, mercury and cadmium, and polychlorinated biphenyls, a known carcinogenic.
The dust that fell on September 11 and in the following days was made up of a range of sizes of particles, and the ultrafine particles are particularly concerning to human health because they can be absorbed into the nervous system via the nasal cavity.
It is widely reported that many first responders and exposed civilians developed a persistent cough following exposure to the dust from the World Trade Centre. The acute health issues that these people dealt with were followed by a wave of chronic diseases that continue to affect them. Respiratory diseases like asthma, chronic obstructive pulmonary disease (COPD) and upper airway diseases.
In addition to chronic respiratory diseases, many first responders were subsequently diagnosed with cancer. Blood and lymphoid tissue cancers such as lymphoma, leukemia and myeloma were prominent, with diagnoses of cancers including breast, head, prostate, lung and neck also recorded.
Mesothelioma is also reported, which is unsurprising given that the early construction of the north tower involved the use of asbestos until public advocacy about the associated health dangers halted its use.
The sheer volume of illness following the events of September 11 has highlighted the importance of adequate personal protective equipment for first responders.