The Risk Management Handbook: The risk management process can be broken down into several key parts: He outlines what risk is and why it matters and brings together the thoughts and opinions of experts in risk to demonstrate how to effectively handle multi-dimensional risk and the emerging trends within the field.
This rule was remanded by the U. Circuit Court of Appeals and the limits are not currently in force.
However, in a enforcement proceeding before the Occupational Safety and Health Review Commission, wood dust was held not to be covered by the nuisance dust standard.
It held that the standard only covered inorganic dusts.
The Agency did not regulate this substance after this decision. For Western red cedar, a highly allergenic species of soft wood, the Agency is establishing an 8-hour TWA limit of 2. Wood dust is defined as any wood particles arising from the processing or handling of woods. Hard woods derive from the deciduous broad-leaved flowering species of trees, and soft woods include the coniferous species that do not shed their leaves in the winter.
Exposure to wood dust has long been associated with a variety of adverse health effects, including dermatitis, allergic respiratory effects, mucosal and nonallergic respiratory effects, and cancer.
The toxicity data in animals are limited, particularly with regard to exposure to wood dust alone; there are, however, a large number of studies in humans.
The discussion below first describes some of the relevant toxicological studies and then presents the record evidence on wood dust. Animals were sacrificed serially at intervals up to 90 days after injection.
Lung examination revealed that, at 90 days, Grade I fibrosis of the lungs had occurred in the guinea pigs injected with mango or jute, while those treated with sheesham or hemp had developed Grade II pulmonary fibrosis.
Histopathological examination showed lung changes, described by the authors as moderate to severe, in all exposed guinea pigs.
The changes seen included an increase in septal connective tissue components and aggregation of lymphocytes; however, no pulmonary fibrosis or extensive destruction of the parenchymal tissue occurred.
The authors of this study concluded that exposure to fir bark dust may cause inflammatory changes in the lung. In each study, the animals were divided into four separate groups. In Study I, there were 12 animals per group.
The third group in Study I was given the DEN doses only positive controland the fourth group was given no exposure at all negative control. In Study II, there were 24 animals in each of four groups.
The positive and negative control groups were treated as in Study I.
In Study I, none of the hamsters had lung or nasal tumors or metaplasia. Four hamsters exposed to wood dust and DEN exhibited squamous cell papillomas of the trachea, as did three animals in the positive control group and one in the negative control group.
No differences in organs other than the respiratory organs were seen between the treated and control groups in Study I. In addition, half of all DEN-exposed hamsters developed nasal adenocarcinomas, whether or not they had also been exposed to wood dust.
Half of the DEN-exposed animals also had papillomas of the larynx and trachea. In the wood-dust-exposure-only group, two of the animals had nasal lesions, one of which was an unclassifiable malignant nasal tumor and the other of which consisted of focal metaplasia with mild dysplasia.
The authors concluded that exposure to wood dust did not increase the tumor incidence in DEN-exposed animals but did affect the respiratory tract of all exposed animals. There are a large number of case reports, epidemiological studies, and other data on the health effects of wood dust exposure in humans.
Dermatitis caused by exposure to wood dusts is common, and can be caused either by chemical irritation, sensitization allergic reactionor both of these together.
As many as species of trees have been implicated in wood-caused dermatitis.
The chemicals associated with allergic reactions are generally found in the inner parts of a tree, e. The symptoms of sensitization are redness, scaling, and itching, which may progress to vesicular dermatitis and, after repeated exposures, to chronic dermatitis. The parts of the body most often affected are the hands, forearms, eyelids, face, neck, and genitals.Recently Published Books The Risk Management Handbook: A Practical Guide to Managing the Multiple Dimensions of Risk by David Hillson, Editor; June 28, .
Toxicological Abbreviations May AA activation analysis; atomic absorption AAF acetylaminofluorene AAPCC American Association of Poison Control Centers AAS atomic absorption spectrophotometry ABS acrylonitrile-butadiene-styrene ACE angiotensin-converting enzyme ACGIH American Conference of Governmental Industrial Hygienists ACh acetylcholine AChE .
The objective of a toxicological risk assessment is to evaluate the potential health risks associated with exposure to leachable impurities, contaminants, or other residues in a medical device or drug product.
MATERIAL SAFETY DATA SHEET Product Name: Genfarm Metsulfuron WG Herbicide This revision issued: September, Page: 1 of 6 Issued by: . Toxicological risk assessments address the risks associated with exposure to potentially haz-ardous substances and can be conducted in one of two ways.
The first is a proactive approach in which the safety of a given substance is evalu-ated prior to exposure. This approach can be used as a tool to find substances of concern and set limits for them.
Understanding the difference between ‘a hazard’ and ‘a risk’ is important for understanding the role of toxicology in assessing risks. A hazard is anything that can cause harm, whereas risk is the potential for a hazard to cause harm.
Risks associated with hazards can be eliminated, or at least greatly reduced, by reducing exposure.