Crete: does farming explain urban and rural differences in atopy?

BACKGROUND: Urban-rural differences in the prevalence of atopy and associated allergic diseases have been reported in several non-European countries. Within Europe, where such variations are less striking, a farm childhood has been postulated to be protective. OBJECTIVE: We aimed to compare the prevalence of atopy in urban and rural children living in Crete and to examine the role of early exposure to a farming environment in explaining any measured differences. METHODS: A cross-sectional survey of children attending secondary schools in Iraklion, the capital city, and five villages 100 km to the south. Atopy was determined by the responses to skin prick tests with seven common aeroallergens. RESULTS: Nine-hundred and ninety-seven children participated in the survey. 19.6% of those living in Iraklion, but only 9.6% of those from the villages, had a positive response to one or more skin prick tests. Among urban children there were significant gradients in the prevalence of atopy across several categories of animal contact and consumption of farm (unpasteurized) milk products--before the age of 5 years. These differences, however, were not apparent among the rural children.

An outbreak of asthma in a modern detergent factory.

The striking decrease in the occurrence of protease-induced occupational asthma in the detergent Industry has been attributed to enzyme encapsulation. We report an outbreak of asthma, at least equal in size to those reported in the 1960s, in a modem European factory which has exclusively used encapsulated enzymes. A survey revealed that enzyme sensitisation and work-related respiratory symptoms were positively correlated with airborne enzyme exposure. We suggest that encapsulation alone is insufficient to prevent enzyme-Induced allergy and asthma.

Occupational asthma caused by bacillary amylase used in the detergent industry.

Four cases are reported of occupational asthma due to amylase derived from Bacillus licheniformis, used in detergent washing powders. It is thought that these are the first reported cases of asthma due to this enzyme in the detergent industry. All four employees (men) were from the same factory and none had a history of asthma or atopy. All developed symptoms of wheeze at work after an initial symptom free period. Symptoms improved during periods away from work. All undertook serial peak flow recordings (not diagnostic) and underwent skin prick tests, radio allergosorbent test (RAST) measurement, and specific bronchial provocation testing. The bronchial provocation testing was performed by a dust tipping method in a single blind manner, with lactose as an inert control and powdered amylase, provided by the employer, as an active agent. Serial measurements of forced expiratory volume in 1 second (FEV(1)) were recorded and histamine provocative concentration causing a 20% fall in FEV(1) (PC(20)) tests were determined before and 24 hours after each challenge. Patient 1 developed an isolated early reaction, patient 2 an isolated late reaction, and patients 3 and 4 developed dual reactions. All showed an increased non-specific bronchial responsiveness after active challenge. The introduction of encapsulated enzymes in the detergent industry was followed by a reduction in the incidence of respiratory sensitisation. These patients developed occupational asthma despite working only with encapsulated enzymes. This highlights the importance of careful surveillance after the introduction of new agents in the workplace.