Chapter 26 - Pesticides and Contact Urticaria Syndrome

Abstract

This chapter provides a brief introduction to the advances and understanding associated with contact urticaria syndrome (CUS; immediate contact reactions). It comprises a wide range of inflammatory reactions that habitually appear within minutes after cutaneous or mucosal contact with the causal agent and disappear within 24 h after contact. However, delayed-onset reactions appearing several hours after exposure are sometimes observed. CUS usually displays a broad spectrum of clinical manifestations ranging from mild erythema and/or itching or burning to severe anaphylactic reactions and even death. It has been reported following skin contact with a multitude of substances ranging from simple chemicals to macromolecules. Its prevalence among the general population is unknown, but it may be a relatively common and under-recognized phenomenon. Contact urticaria (CU) usually clears spontaneously, usually in a few hours; repeated exposure may lead to dermatitis (eczema). In addition, CU may be associated with allergic contact dermatitis (type IV hypersensitivity). Assessing and managing the occupational health risks posed by the use of pesticides in agriculture is a complex but essential task for occupational health specialists and toxicologists. Increased awareness of the signs and symptoms of CUS will lead to increased frequency of diagnosis, which is especially important for ICU. Product information formulated by the registrant would help the health care community (and the worker/patient) by including what is known (and not known) of the potential for developing immunologic and nonimmunologic contact urticaria.