![Sample our Medicine, Dentistry, Nursing & Allied Health journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/5944/TOC-Subject-Sample-2021-Medicine-Dentistry-Nursing-Allied-Health.jpg"})
Abstract
The World Trade Center (WTC) twin towers in New York City collapsed on 9/11/2001, converting much of the buildings’ huge masses into dense dust clouds of particles that settled on the streets and within buildings throughout Lower Manhattan. About 80–90% of the settled WTC Dust, ranging in particle size from ∼2.5 μm upward, was a highly alkaline mixture of crushed concrete, gypsum, and synthetic vitreous fibers (SVFs) that was readily resuspendable by physical disturbance and low-velocity air currents. High concentrations of coarse and supercoarse WTC Dust were inhaled and deposited in the conductive airways in the head and lungs, and subsequently swallowed, causing both physical and chemical irritation to the respiratory and gastroesophageal epithelia. There were both acute and chronic adverse health effects in rescue/recovery workers; cleanup workers; residents; and office workers, especially in those lacking effective personal respiratory protective equipment. The numerous health effects in these people were not those associated with the monitored PM2.5 toxicants, which were present at low concentrations, that is, asbestos fibers, transition and heavy metals, polyaromatic hydrocarbons or PAHs, and dioxins. Attention was never directed at the very high concentrations of the larger-sized and highly alkaline WTC Dust particles that, in retrospect, contained the more likely causal toxicants. Unfortunately, the initial focus of the air quality monitoring and guidance on exposure prevention programs on low-concentration components was never revised. Public agencies need to be better prepared to provide reliable guidance to the public on more appropriate means of exposure assessment, risk assessment, and preventive measures.
Acknowledgements
We acknowledge ongoing support services provided by the New York University, and by the National Institute of Environmental Health Sciences under an NIEHS Center Grant (ES 000260) and a Research Grant from CDC/NIOSH (OH008280). We also acknowledge receipt of previously unpublished technical information on the results of experiments to determine rates of resuspension of undisturbed WTC settled dust from the RJ Lee Group (Monroeville, PA) and their permission to cite their work in this paper. We also acknowledge the input of invited pre-submission reviewers (Drs. Robert Maynard, Richard Lee, Paul Lioy, and Joan Reibman). The authors gratefully acknowledge the careful and thorough review comments supplied by the five peer reviewers. The revised submission reflects our inclusion of changes made in response to the review comments.
Declaration of interest
The affiliation of the three authors is as shown on the cover page. Their preparation of this paper was supported, in part, by NIEHS (ES 000260), which has provided Center Program support for the authors’ research at NYU. Dr. Cohen's toxicological research on the health effects of WTC Dust was supported by a research grant from CDC/NIOSH (OH008280). Dr. Chen's research on the characterization of the particle size distribution and chemical composition of WTC Dust was supported by a supplement to the NIEHS Center Grant (ES-000260). The authors received no external funding for the preparation of this paper. Dr. Chen has offered advice to government agencies on addressing the hazards of WTC Dust. Dr. Lippmann has offered advice to the EPA on identifying a signature component of WTC Dust (CitationLowers et al. 2009, CitationMeeker et al. 2010). Dr. Lippmann has been retained as an expert in a case involving alleged health effects related to exposure, to WTC Dust, of workers engaged in the cleanup of Lower Manhattan building interiors following September 11, 2001. Drs. Chen and Cohen served on the NYC Mayor's WTC Medical Working Group. The data summaries, other than those cited in Table and Figure captions, represent the authors’ syntheses. The interpretations of the data in this critical review are exclusively those of the authors, and do not represent those of NYU, NIEHS, or CDC/NIOSH.