Identification of the physical and chemical characteristics of volcanic hazards

Principles of fluoride toxicity and the cellular response: a review

Fluoride is ubiquitously present throughout the world. It is released from minerals, magmatic gas, and industrial processing, and travels in the atmosphere and water. Exposure to low concentrations of fluoride increases overall oral health. Consequently, many countries add fluoride to their public water supply at 0.7-1.5 ppm. Exposure to high concentrations of fluoride, such as in a laboratory setting often exceeding 100 ppm, results in a wide array of toxicity phenotypes. This includes oxidative stress, organelle damage, and apoptosis in single cells, and skeletal and soft tissue damage in multicellular organisms. The mechanism of fluoride toxicity can be broadly attributed to four mechanisms: inhibition of proteins, organelle disruption, altered pH, and electrolyte imbalance. Recently, there has been renewed concern in the public sector as to whether fluoride is safe at the current exposure levels. In this review, we will focus on the impact of fluoride at the chemical, cellular, and multisystem level, as well as how organisms defend against fluoride. We also address public concerns about fluoride toxicity, including whether fluoride has a significant effect on neurodegeneration, diabetes, and the endocrine system.

GRACE: public health recovery methods following an environmental disaster

Different approaches are necessary when community-based participatory research (CBPR) of environmental illness is initiated after an environmental disaster within a community. Often such events are viewed as golden scientific opportunities to do epidemiological studies. However, the authors believe that in such circumstances, community engagement and empowerment needs to be integrated into the public health service efforts in order for both those and any science to be successful, with special care being taken to address the immediate health needs of the community first, rather than the pressing needs to answer important scientific questions. The authors will demonstrate how they have simultaneously provided valuable public health service, embedded generalizable scientific knowledge, and built a successful foundation for supplemental CBPR through their on-going recovery work after the chlorine gas disaster in Graniteville, South Carolina.

Natural and technologic hazardous material releases during and after natural disasters: a review

Natural disasters may be powerful and prominent mechanisms of direct and indirect hazardous material (hazmat) releases. Hazardous materials that are released as the result of a technologic malfunction precipitated by a natural event are referred to as natural-technologic or na-tech events. Na-tech events pose unique environmental and human hazards. Disaster-associated hazardous material releases are of concern, given increases in population density and accelerating industrial development in areas subject to natural disasters. These trends increase the probability of catastrophic future disasters and the potential for mass human exposure to hazardous materials released during disasters. This systematic review summarizes direct and indirect disaster-associated releases, as well as environmental contamination and adverse human health effects that have resulted from natural disaster-related hazmat incidents. Thorough examination of historic disaster-related hazmat releases can be used to identify future threats and improve mitigation and prevention efforts.

Ethnic patterns of thyroid cancer incidence in the United States, 1973-1981

Descriptive epidemiological findings for 7,696 patients with newly diagnosed thyroid cancer reported to the Surveillance, Epidemiology, and End Results (SEER) program for the years 1973 through 1981 are summarized. The preponderance of this tumor in women and of the papillary histologic subtype are well documented. The data suggest that previously reported increases in the incidence of thyroid cancer among Whites levelled off in the late 1970s. Differences in the incidence of this cancer according to ethnic group were particularly striking. Compared with White men and women, Puerto Rico Hispanics and Blacks had significantly lower thyroid cancer rates (weighted rate ratios ranged from 0.48 to 0.65). New Mexico Hispanic men and Chinese, Japanese, Hawaiian and Filipino men and women had significantly higher rates (weighted rate ratios ranged from 1.56 to 3.17). Elevated thyroid cancer rates for residents of Hawaii, regardless of ethnic group, were also a noteworthy finding. Variations in thyroid cancer risk according to ethnic group and geographical residence may reflect socio-economic or local environmental influences, including the possibility of a carcinogenic agent in volcanic lava.