David Baker

At the end of this chapter and any recommended reading the student should be able to 1. explain the normal structure and function of the human body systems, and the concept of target organs and systems 2. explain, with the use of examples, how dysfunction in each of the important body systems may occur following exposure to toxic agents 3. describe and discuss the manifestations of dysfunction in each of the important systems of the human body 4. demonstrate awareness of the common chemicals...

Organic irritants

The combustion of organic compounds also results in the formation of organic irritant products in the fire effluent. The incomplete combustion or pyrolysis of materials including wood, fossil fuels, synthetic and natural polymers, and foodstuffs gives rise to a range of aldehydes (International Programme on Chemical Safety 1991). Of this group, acrolein and formaldehyde are the best known, although it is highly unlikely that these will be the sole organic irritants present in fire smoke, which...

Gaseous air pollutants

Ozone is a classic secondary air pollutant there are no significant outdoor and few indoor sources of ozone. It is important to distinguish between the ozone of the stratosphere, which protects against UV radiation and which is depleted by halogenated compounds, and the ozone of the troposphere, which affects health. The ozone of the troposphere comes largely from a series of photochemical (light-driven) reactions that depend on three things light, oxides of nitrogen, and organic compounds....

Health Issues for vulnerable groups

The individuals who are most at risk from exposure to combustion products are those who have pre-existing respiratory diseases, such as asthma or chronic obstructive pulmonary disease. The presence of an existing respiratory condition increases the susceptibility of the individual to the adverse effects of exposure to asphyxiant gases such as CO (International Programme on Chemical Safety 1999). Acute exposure to smoke containing mixtures of asphyxiant and irritant gases is therefore likely to...

Vinyl chloride exposure and health effects

Vinyl chloride (Figure 8.2), which is produced for industrial use as a chemical intermediate in the manufacture of other compounds, particularly polyvinyl chloride (PVC), is toxic by all routes of exposure. It is metabolized to the active metabolites chloroethylene oxide and chloracetaldehyde, which is responsible for its toxicity. In the absence of proper controls, acute exposure will produce immediate signs and symptoms, such as respiratory irritation, producing coughing, wheezing, and...

Box 122 Food additives

Food additives have a technological function in food. Important subcategories are flavour enhancers and flavourings emulsifiers, stabilizers, gelling agents, and thickeners. Fig. 12.1 Derivation of an acceptable or tolerable daily intake. Fig. 12.1 Derivation of an acceptable or tolerable daily intake. identified (the NOAEL). The NOAEL is divided by uncertainty factors (or safety factors) to allow for interspecies differences if the NOAEL is derived from a study in laboratory animals, and for...

Inorganic acid gases

The most common inorganic acid gases evolved during combustion include the halogen acids (HCl, HF, HBr) and oxides of sulphur, nitrogen, and phosphorus (Department of Health 1996). Production of these gases will be dependent on the chemical composition of the materials involved. Hydrogen chloride Hydrogen chloride (HCl) is the most important halogen acid gas likely to be evolved during combustion (Hartzell 1996). Because of the chlorine content of many commonly used materials, including...

During breastfeeding

As a general rule, breast-feeding mothers should avoid 1. remedies containing high doses of herbs containing alkaloids, particularly those that may affect the nervous system, e.g. the Chinese herbs coptis, philodendron (berberine alkaloids), sophora root (oxymantrine), ma-huang (ephedrine), and evodia (rutecarpine) 2. remedies containing high doses of herbs known to have hormonal effects, e.g. fennel, anise, liquorice 3. herbs containing plant alkaloids known to cause liver and or kidney...