Article Abstract:
Satisfactory surveillance of the work environment and employee health presents a major challenge. The usual approaches to minimize worker exposure to suspected carcinogens in the ambient environment are no longer satisfactory. These approaches fail to consider the influence of intermediary processes between exposure and the development of the cancer. Furthermore, for employees exposed to many potential carcinogens, biological markers and biologically effective exposures and doses must be determined for each compound. Chemical carcinogens exert their effects by producing either direct genetic damage or secondary damage that alters potential genetic expression. Compounds in the work environment may affect oncogenes (genes that stimulate the transformation of the host cell to a cancer cell) or antioncogenes (tumor suppressor genes). It is known that no single gene alone is responsible for the transition from normal to malignant cell type. The transition process after exposure to chemical carcinogens to the development of tumor depends on the action and interaction of certain oncogenes and antioncogenes. One such oncogene is the ras oncogene, which is know to be activated in the development of many human cancers, especially lung cancer. Malignancies are also associated with exposure to chemical carcinogens, such as the polycyclic aromatic hydrocarbons (PAHs). The PAHs are products of high temperature combustion of carbon-containing compounds, and are in cigarette smoke and are products of the coal and coke, iron and steel, rubber tire, and petroleum industries. The ras oncogene can be activated by specific point mutations produced by the action of these compounds. As with other genes, the ras oncogene exerts a specific influence through the expression of a specific protein product, p21. There is evidence of ras oncogene activation and p21 expression in human lung cancers. The detection of the ras oncogene/p21 in these cases suggests that they may be useful as a cancer biomarker for individuals exposed to respiratory carcinogens. (Consumer Summary produced by Reliance Medical Information, Inc.)
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
In the US, it is estimated that there are 80,000 forest or wilderness firefighters. Wildland fires generate large quantities of particulates in the air that can irritate the eyes, nose, throat, and lungs. The extent of exposure to the particulates while fighting a wildland fire depends on the size of the fire, the wind, the terrain and the methods used for putting out the fire, such as spraying with water versus setting backfires. Firefighting is physically demanding and increases the breathing rate, which in turn increases the amount of particulates that are inhaled. Wildland fires tend to burn for long periods of time and it is common for crews to work for 12 to 18 hours per day. During very large fires, camps are established near the fire and the crew is continuously exposed to smoke from the wildland fire. A study was performed to evaluate the pulmonary effects of inhaling smoke from wildland fires. The study included 52 wildland firefighters who work in the foothills of the Sierra Nevada mountains in Northern California. The firefighters were between the ages of 18 and 45, and they did not smoke. Lung function was evaluated by measuring the amount of air that could be forcefully exhaled from the lungs in one second (FEV1, forced expiratory volume) and the total amount of air that could be exhaled from the lungs following a deep breath (FVC, forced vital capacity). Recent firefighting activity was associated with decreases in both FEV1 and FVC, and was associated with eye irritation, nose irritation, and wheezing. Wearing a cotton bandanna over the nose and mouth, a common practice of firefighters, did not protect against lung symptoms or declines in lung function. It is concluded that more effective methods are needed for protecting the lungs during prolonged periods of firefighting. (Consumer Summary produced by Reliance Medical Information, Inc.)
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
Loggers are exposed to a number of work-related hazards, such as trauma. Wood dust and fumes from chain saws and equipment are also encountered daily, and may be detrimental to pulmonary (lung) function. This study examined pulmonary function data from 688 loggers, which was compared with values obtained by the National Institute for Occupational Safety and Health (NIOSH) for non-exposed blue-collar workers in other professions. The possibility of greater risk of pulmonary impairment among loggers was investigated, along with any relationship to length of employment and work activity associated with impairment. Data was obtained from loggers in Oregon and Washington who were originally studied for the effects of exposure to volcanic ash. More than two thirds of the loggers were current or ex-smokers. Employment times averaged 11 to 14 years. Loggers' lung data were compared with other workers by smoking status. Loggers had greater forced expiratory volume in one second and forced vital capacity than predicted; the ratio of forced expiratory volume in one second/forced vital capacity values was less than comparable NIOSH groups. These results indicate that loggers are not at increased risk for pulmonary disease and that the NIOSH study predictions for other blue-collar workers are not applicable to loggers. (Consumer Summary produced by Reliance Medical Information, Inc.)
User Contributions:
Comment about this article or add new information about this topic: