Thursday, August 1, 2019

Persistent Organic Pollutants and Food Allergy Essay

Persistent organic pollutants (POPs) are compounds with cyclic, halogenated and are organic in nature characteristics that impart stability in their structures (Ritter, Solomon, Forget, Stemeroff, and O’Leary, 1995). Because of its structural stability, POPs withstand degradation while its organic nature makes its solubility high in lipid or organic solvent but low in water and in other inorganic solvents. Additionally, their semi-volatile nature allows them to exist in vapor or be deposited on atmospheric particulates. Food allergy is a result of the abnormal response of the body’s immune system to foods that may cause grave illness and even death (U. S. Department of Health and Human Services, 2007). It is mistakenly associated with food intolerance which is a digestive problem and can not be attributed to food allergy. In addition, food intolerance is not caused by the action of the immune system rather by the lack of specific metabolic enzyme needed in the digestion of a particular food (U. S. Department of Health and Human Services, 2007). Individuals with familial allergy background are prone to food allergies and other allergic diseases like asthma. Meanwhile, the gastrointestinal tract, skin, lungs, throat, and skin are often sites of allergic reactions (U. S. Department of Health and Human Services, 2007). Persistent Organic Pollutants Organo-halogenated compounds such as toxaphene, chlordane, dieldrin, dibenzo-p-dioxins, DDT, dibenzo-p-furans, and polychlorinated biphenyls or PCBs are known for their structural stability and environmental persistence, thus, bioaccumulation results as they continuously flow in the ecological food chain (Ritter, Solomon, Forget, Stemeroff, and O’Leary, 1995). As an example, PCBs resist degradation for several years and biomagnify by 70,000 folds. Since POPs are semi-volatile, they evaporate from warm regions and condense in geographical areas like mountain terrains and Polar Regions (California Breast Cancer Research Program, 2007). These properties permeated PCBs in worldwide places including Antarctic, arctic, and desert regions where chemical plants do not exist. Most POPs came from anthropogenic sources like industrial production and foliar applications of pesticides and insecticides while others such as dioxins and furans are just by-products of the manufacturing process, waste incineration, forest fires, and metallurgical processes (Environmental Literacy Council, 2008). As such, the presence of PCBs in far flung places is a manifestation of its worldwide-dispersal from several industrial sources. In fact, fifteen nanograms per cubic meter of PCBs’ concentration have been analyzed in the atmosphere of industrialized areas and different places over the world (Ritter, Solomon, Forget, Stemeroff, and O’Leary, 1995). Thus, the PCBs’ presence in rain and snow would not be a surprise. Exposure to POPs by means of food consumption, industrial occupation, and pollutants may lead to toxicity. POPs’ lipophilicity or high solubility in lipids in coupled with its structural stability and biomagnification in the food chain result to high risk of bioaccumulation and toxicity among living organisms. More than these, metabolic conversion of POPs into more persistent compounds is also possible. Researches conducted on this matter showed the correlations of PCBs’ ingestion with the dysfunction of endocrine, reproductive, and immune systems, cancer, neurobehavioral disorders and some infant abnormalities (Ritter, Solomon, Forget, Stemeroff, and O’Leary, 1995). Moreover, exposure to POPs’ has been correlated with a decrease in the population of marine organisms like dolphins, whales, and fish species (Ritter, Solomon, Forget, Stemeroff, and O’Leary, 1995). Food Allergy Food allergens are proteins in foods that after digestion run through the bloodstream to specific body parts and triggers allergic reactions (U. S. Department of Health and Human Services, 2007). Allergic reactions may take place either at the specific cells or within the whole body (Jackson, 2003). The length of digestive process determines the possible time and location of the allergic reactions. If one is highly sensitive to substances present in food, by merely just chewing the food allergic reaction may start at the mouth. Most of the time stomachache, vomiting, and diarrhea are observed after eating which indicate allergic reactions. After food digestion, food allergens flow through the bloods stream and may trigger blood pressure lowering. Nonetheless, reaching the skin, mouth, and lungs, may cause hives, itchiness, and even smothering (U. S. Department of Health and Human Services, 2007). Antibodies or immunoglobulins are protein substances secreted by B-lymphocytes to work against antigens or allergens (Jackson, 2003). Antigens are exuded by bacteria or other microorganisms which brings bodily infections. However, the extraneous production of antibodies may cause illness (Jackson, 2003). Meanwhile, potential antigens are also present in dust, pollens and foods. By means of direct contact, inhalation or consumption of these antigens, the body generates appropriate antibodies to combat their infectious effects (Jackson, 2003). The immune system has two consecutive actions leading to allergic reaction. During the digestion of foods, the immune system produces immunoglobulin-E (IgE), an antibody which is protein in nature (U. S. Department of Health and Human Services, 2007). Then, IgE adheres with basophils and mast cells located in blood and body tissues respectively. This food-specific antibody educes the cells to elicit chemicals like histamine which in turn produces allergy (U. S. Department of Health and Human Services, 2007). Mechanism of Allergic Reaction The production of allergens signals the action and circulation of IgE through the blood stream to bodily parts. The IgE molecule has a specific site for antigen binding and receptor-specific end for cell attachment. Then, the IgE attracts antigen as it binds on the surface of the cell (Jackson, 2003). As such, the cell is incited by the antigen to generate antibodies. The cell becomes sensitive to the subsequent attacks of the same antigens and autonomic response develops. Thus, as the cell detects the presence of the antigen, it educes biologically active and other proinflammatory substances like histamines and leukotrienes (Jackson, 2003). These substances trigger the inflammatory response of the cell resulting to an increased blood supply and other immune system components on the affected area that can be observed as itching and swelling (Jackson, 2003). Since mast cells and basophils are located in different body parts, immediate allergic reactions are often observed in some individuals who are highly sensitive with allergies. As a result of allergen absorption and wide circulation of chemical mediators, the body can be systematically engrossed with allergic reactions (Jackson, 2003). The intestine has defensive barriers that prevent the entry and contact of any antigens with the mast cells (Jackson, 2003). Also, the gut wall is covered with viscous mucus secreted by the lining cells. This mucus has protective substances acting as antiseptic coupled with the help of antibodies. Then, epithelial cells are located below the mucus membrane, which generate enzymes that can deactivate histamine and other bioactive substances (Jackson, 2003). Allergens that may infiltrate the layer of epithelial cells can be deactivated by antibodies without inflammatory response production. If the antigens were able to escape all these mechanisms, mast cells covered by IgE produce chemical mediators that in turn cause inflammatory response (Jackson, 2003). Conclusion The genetic predisposition causes individuals with familial allergic history to become susceptible to allergic reactions as triggered by specific antibody or allergen. As a result, asthma, rhinitis, and even anaphylaxis can be observed wit these individuals (Jackson, 2003). This inborn allergic tendency is called atopy, thus, individuals in this condition are tagged as atopic. On the other hand, contemporary theory on the nature of allergy suggested that the prevalence of allergy-related cases nowadays can be attributed to the modern life style (Jackson, 2003). For instance, drug treatment of a mother during pregnancy and infant’s medication may contribute to early acquisition of allergic tendency due to the body’s adverse reaction with drugs (Jackson, 2003). Also, the inhalation of bacteria or other microorganism through air pollutants and other atmospheric particulates that may include persistent organic pollutants or POPs provoke the immune system to produce antibodies then, allergic reactions spontaneously occur.

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