Pine processionary development, pine processionary caterpillars are highly irritating to the skin. Contact with the hairs of the caterpillar can cause severe rashes (urticaria) and eye irritation. Some individuals may have an allergic reaction to the caterpillar's hairs. 5th stage larvae can eject hairs when threatened or stressed; the hairs, which have the form of harpoons, then penetrate and irritate all areas of exposed skin nearby with an urticating protein. Allergic reactions may follow in susceptible individuals on subsequent exposure to the hairs. The pine processionary is an economic pest in coniferous forests in southern Europe. It is controlled to some extent
California Office of Environmental Health Hazard Assessment against expansion of OEHHA: OEHHA's vision is to be California's leading scientific organization for evaluating risks to human and ecological health. OEHHA's goals as a governmental agency include: OEHHA assesses the risk of environmental chemicals based on health considerations alone. In contrast, risk managers consider economic and technical feasibility as factors in their decisions. This separation is essential to prevent undue political influence on the evaluation of health risks. These factors are and should remain explicitly excluded from the assessment of risk. OEHHA plays a critical and unique role that allows for the separation of risk assessment and hazard evaluation