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Toxicology of CERCLA Hazardous Substances
Published in Barry L. Johnson, Impact of Hazardous Waste on Human Health, 2020
Immunotoxicology is a relatively new specialty in the field of toxicology. Laboratory methods are emerging to screen chemicals for immunotoxicity. In the meantime, physicians use laboratory tests to measure the number, kind, and ratio of T lymphocytes and B lymphocytes and their subsets to diagnose the status of immune function. Tests, such as skin patch tests, can assess allergic responses to antigens.
Biological hazards
Published in Sue Reed, Dino Pisaniello, Geza Benke, Kerrie Burton, Principles of Occupational Health & Hygiene, 2020
Margaret Davidson, Sarah Thornton
Materials of biological origin can cause allergic reactions in workers who come into contact with them. An allergic response occurs when the human body identifies a foreign material (antigen) and an immune response is stimulated. The body reacts to the presence of antigens by forming antibodies, which bind to the antigens and normally render them harmless. Sometimes the body overreacts to an antigen and this process results in inflammation and tissue damage—that is, an allergic reaction/hypersensivity disease (Tillman 2007). There are four types of allergic/hypersensitivity reaction: Type 1: Immediate hypersensitivity, characterised by a rapid reaction (15–30 minutes) mediated by immunoglobulin E (IgE). Diseases include asthma, eczema, conjunctivitis, allergic rhinitis and gastroenteritis (Bogaert et al. 2009).Type 2: Cytotoxic hypersensitivity occurs when antigens bind to cells and may affect a variety of organs and tissues. Type 2 is primarily mediated by IgM and IgG. Diseases include anaphylactic shock in response to pencillin, and rheumatic fever. Type 3: Immune-complex hypersensitivity may occur three to 10 hours after exposure and involves exposure to soluble antigens that are not attached to the target organ, and mediated IgG, IgM and complement. Examples of immune-complex diseases include hypersensitivity pneumonitis (Bogaert et al. 2009).Type 4: Delayed hypersensitivity is associated with many infectious diseases including leprosy, toxoplasmosis and tuberculosis, as well as contact dermatitis expressed as papular lesions. Unlike Types 1 to 3, Type 4 is cell rather than antibody mediated. The response time is 48–72 hours (Bogaert et al. 2009). The lungs are particularly susceptible to allergens because they are exposed to large quantities of airborne substances. They respond in a variety of ways depending on various extrinsic or intrinsic factors, including the antigen itself, genetics, whether the person smokes, exposure time and intensity (Macher 1998). The body’s response to inhaled allergens can range from mild rhinitis (hayfever) to the more severe allergic asthma and allergic alveolitis discussed below.
A comprehensive summary of disease variants implicated in metal allergy
Published in Journal of Toxicology and Environmental Health, Part B, 2022
Immediate hypersensitivity laryngitis is an allergic response that manifests in the upper airways and selectively affects the larynx (Campagnolo and Benninger 2019). Although the larynx may be one of the tissues involved in other allergic responses of the respiratory tract (e.g., asthma and rhinitis), immediate hypersensitivity laryngitis is characterized by an isolated site of involvement following antigen challenge. The immediate onset of symptoms in this condition suggests involvement from antigen-specific IgE molecules, although the underlying mechanisms of immediate hypersensitivity laryngitis have yet to be specifically determined. Although similar immunological mechanisms may be involved in this condition and other immediate-type allergic responses of the respiratory tract, immediate hypersensitivity laryngitis tends to emerge independently of other allergic diseases and is rarely identified in conjunction with asthma.