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Toxicity and Toxins
Published in Gary S. Moore, Kathleen A. Bell, Living with the Earth, 2018
Gary S. Moore, Kathleen A. Bell
An exaggerated immune response to the presence of an antigen is termed hypersensitivity or allergy. Allergies are the other side of the two-edged sword of immunity. These immune reactions are usually unnecessary, harmful, and sometimes fatal. People have developed allergies to most everything including insect bites, pollen and other plant products, environmental toxins, a variety of foods, sunlight, human semen and much more. Some people have become so sensitized to chemical substances they are unable to physically cope in routine surroundings. Such people are said to have multiple chemical sensitivities (MCS). There has also been a significant increase in the numbers and severity of asthma cases globally. The prevailing scientific thought is that environmental pollutants such as ozone and fine particulates contribute to this increase.14
AI and the Bioscience and Clinical Considerations for Immunology
Published in Louis J. Catania, AI for Immunology, 2021
After a susceptible person is exposed to an allergen, the body starts producing a large quantity of IgE antibodies. This results in the reoccurrence of the allergic response, sometimes with increasing intensity with each re-exposure to the allergen. Included among its cytokines, are histamine and heparin (mentioned above), which along with other inflammatory symptoms, produces itching. With the allergic and hypersensitivity response, symptoms can also include, sneezing, and congestion (from histamine release and degranulation of mast cells – in Figure 2.3). In their most severe form, allergy or hypersensitivity can produce a life-threatening condition call anaphylaxis and anaphylactic shock.13
Toxicogenic theory
Published in Herman Staudenmayer, Environmental Illness, 2018
The putative offending environmental exposure is said to create a priming effect called “sensitization”. Once an individual is sensitized, a hypersensitivity reaction occurs to subsequent, low-level chemical exposure. The effect may be long-lasting. Behavioral and biological sensitization is one of the most fundamental forms of learning and reflects change in an organic process due to prior experience (Razran, 1971). Numerous studies have shown sensitization of behavioral and physiologic parameters, even at the cellular level.
A comprehensive summary of disease variants implicated in metal allergy
Published in Journal of Toxicology and Environmental Health, Part B, 2022
Finally, type IV hypersensitivity responses involve delayed-type allergic reactions mediated by antigen-specific T-lymphocytes. Four subtypes of type IV allergic responses have been described – each of which involves distinctive underlying immunological mechanisms orchestrated by different subsets of effector T-cells. Type IVa reactions involve the actions of CD4 + T helper 1 cells (Th1) and subsequent activation of macrophages (Phillips et al. 2019). Type IVb responses are mediated by T helper 2 cells (Th2) and facilitate eosinophilic inflammation. Type IVc hypersensitivity responses involve CD8+ cytotoxic T-lymphocytes (CTL) with direct cell-killing capabilities. The final subtype of delayed hypersensitivity reactions, type IVd responses, implicate T-cell-induced neutrophilic inflammation (Hausmann, Schnyder, and Pichler 2010). Common examples of type IV hypersensitivity responses include allergic contact dermatitis (ACD), tuberculin reactions, and Stevens-Johnson syndrome.
Genetic variants affecting chemical mediated skin immunotoxicity
Published in Journal of Toxicology and Environmental Health, Part B, 2022
Isisdoris Rodrigues de Souza, Patrícia Savio de Araujo-Souza, Daniela Morais Leme
Much of the difficulty in reducing the incidence of immune skin disorders mediated by chemicals is attributed to lack of knowledge regarding chemical-mediated effects on the immune system, especially when different genetic backgrounds are taken into consideration. Genes are the fulcrum for development and function of immune cells (Lee and Lawrence 2018). The lack of knowledge on the contribution of genetic factors in inter-individual variability to chemical toxicity is also a limiting factor for estimating the risks of chemicals. Predicting all the immunological reactions that different individuals might exhibit to the plethora of chemicals currently available is not possible. Further, failure to identify alterations in the immune system after chemical exposure does not necessarily mean the absence of toxicological risk. Human genetic variability might lead to uncertainties in predicting the risk of immunotoxic responses to chemicals, especially regarding hypersensitivity and autoimmunity.
Toxicological profile of bisphenol F via comprehensive and extensive toxicity evaluations following dermal exposure
Published in Journal of Toxicology and Environmental Health, Part A, 2022
Sang-Sik Lee, Hyeon-Yeol Ryu, Kyu-Sup Ahn, Somin Lee, Jiho Lee, Jae Won Lee, Soo Min Ko, Woo-Chan Son
The skin sensitization test evaluates whether contact dermatitis is initiated by a delayed hypersensitivity reaction (Type 4 hypersensitivity reaction). In this study, administration of 2,000 mg/L BPF produced a strong (Level IV) sensitization reaction with a sensitization rate of 70%. Although the concentration used herein was higher than the actual safety standards established in various countries, no apparent previous studies examined skin sensitization effects of BPF except for a study by Bruze (1986) but toxicity data are lacking. Using a 20-year follow-up human baseline patch test, some investigators reported a contact allergy in 66 (3.3%) out of 1972 workers handling BPF epoxy resins (Aalto-Korte et al. 2014; O’Boyle et al. 2012). Although the present study indicated that sensitization via direct skin exposure to BPF warrants consideration, further research is needed to identify the mechanisms through which BPF elicits such a response.