Adverse reactions to sulfites
(Yang and Purchase 1985) Download
Sulfites are widely used as preservatives in the food and pharmaceutical industries. In the United States more than 250 cases of sulfite-related adverse reactions, including anaphylactic shock, asthmatic attacks, urticaria and angioedema, nausea, abdominal pain and diarrhea, seizures and death, have been reported, including 6 deaths allegedly associated with restaurant food containing sulfites. In Canada 10 sulfite-related adverse reactions have been documented, and 1 death suspected to be sulfite-related has occurred. The exact mechanism of sulfite-induced reactions is unknown. Practising physicians should be aware of the clinical manifestations of sulfite-related adverse reactions as well as which foods and pharmaceuticals contain sulfites. Cases should be reported to health officials and proper advice given to the victims to prevent further exposure to sulfites. The food industry, including beer and wine manufacturers, and the pharmaceutical industry should consider using alternative preservatives. In the interim, they should list any sulfites in their products.
Although molybdenum was first identified as an element over two centuries ago, its biological importance was not appreciated until researchers demonstrated it had a direct role in animal metabolism. Molybdenum has since been identified as an essential trace element for nearly all plants and animals, occurring as a cofactor in three important enzymatic reactions that take place in virtually all forms of life. Clinically, molybdenum deficiency is rare, but inborn errors of metabolism resulting in deficiencies of the molybdoenzymes have been described. Dietary intake of molybdenum is generally sufficient, with legumes such as lentils, beans, and peas being the richest source. Nuts, grains, cauliflower, and leafy vegetables are also good sources, whereas animal products and fruit are low in molybdenum. Molybdenum content of plant-based foods is dependent on the amount of molybdenum in the soil in which they are grown. Molybdenum supplementation may be of therapeutic benefit in patients with molybdoenzyme deficiency, sulfite sensitivity, Wilson's disease, and certain types of cancer, and in those receiving total parenteral nutrition.
Food Additives and Sensitivities
(Rangan and Barceloux 2009) Download
Clinical effects of sulphite additives
(Vally, Misso et al. 2009) Download
Sulphites are widely used as preservative and antioxidant additives in the food and pharmaceutical industries. Topical, oral or parenteral exposure to sulphites has been reported to induce a range of adverse clinical effects in sensitive individuals, ranging from dermatitis, urticaria, flushing, hypotension, abdominal pain and diarrhoea to life-threatening anaphylactic and asthmatic reactions. Exposure to the sulphites arises mainly from the consumption of foods and drinks that contain these additives; however, exposure may also occur through the use of pharmaceutical products, as well as in occupational settings. While contact sensitivity to sulphite additives in topical medications is increasingly being recognized, skin reactions also occur after ingestion of or parenteral exposure to sulphites. Most studies report a 3-10% prevalence of sulphite sensitivity among asthmatic subjects following ingestion of these additives. However, the severity of these reactions varies, and steroid-dependent asthmatics, those with marked airway hyperresponsiveness, and children with chronic asthma, appear to be at greater risk. In addition to episodic and acute symptoms, sulphites may also contribute to chronic skin and respiratory symptoms. To date, the mechanisms underlying sulphite sensitivity remain unclear, although a number of potential mechanisms have been proposed. Physicians should be aware of the range of clinical manifestations of sulphite sensitivity, as well as the potential sources of exposure. Minor modifications to diet or behaviour lead to excellent clinical outcomes for sulphite-sensitive individuals.
(2006). "Molybdenum - monograph." Altern Med Rev 11(2): 156-61.
Rangan, C. and D. G. Barceloux (2009). "Food additives and sensitivities." Dis Mon 55(5): 292-311.
Vally, H., N. L. Misso, et al. (2009). "Clinical effects of sulphite additives." Clin Exp Allergy 39(11): 1643-51.
Yang, W. H. and E. C. Purchase (1985). "Adverse reactions to sulfites." CMAJ 133(9): 865-7, 880.