Work related symptoms, sensitisation, and estimated exposure in workers not previously exposed to laboratory rats.

Abstract

Findings are presented from the initial cross sectional phase of a cohort study of employees exposed to laboratory rats. Of 366 eligible workers at four sites 323 (88%) were surveyed; symptoms assessed by self completed questionnaire and sensitisation measured by the response to skin prick tests were related to intensity of exposure both to total dust and to rat urinary aeroallergen. Among 238 workers, without previous occupational expo--sure to rats, work related symptoms, which started after first employment at the site were related to exposure intensity (expressed either in terms of dust or of aeroallergen) at the time of onset of symptoms. These relations were stronger in atopic subjects but were unrelated to smoking. Positive skin tests to rat urinary extract were also more frequent with increased exposure, a relation found in both atopic subjects and in smokers. There was a strong association between work related symptoms and specific sensitisation. ( information; the current cohort study was designed to correct these deficiencies. We report findings of the initial phase. Subjects and methods SURVEY METHODSFour institutions specialising in small animal research in the United Kingdom were identified: three use a variety of animals including rats; the fourth uses almost exclusively mice and is not described in this paper. All full time employees in occupational groups where exposure to laboratory rats or mice was probable and a group of non-exposed office workers, who had started work at the site from 1 January 1986 onwards and had worked for at least one month, were invited to participate.Members of the cohort still employed at the sites have been surveyed at six-monthly intervals since 1990. We describe the findings from the initial survey. Two visits to each site were made, the second to collect information from those missed at the first visit. Of 366 eligible subjects 323 (88%) were surveyed, with no difference in response rates between the three workforces. Questionnaires were completed by 315 subjects (84%) and skin prick tests by 295

New occupational allergen in citrus farmers: citrus red mite (Panonychus citri)

“…Cross-sectional studies of laboratory animal workers have suggested that asthma may be an endresponse in a chain of occupational sensitization, which begins with eye and nose symptoms, 22 although little evidence for such a temporal relationship was found in a longitudinal study of a similar workforce. 23 In this study, all patients except one with CRM-induced occupational asthma complained of concurrent nasal symptoms, which had developed at an earlier time than the development of asthmatic symptoms. This finding suggests that CRM-induced occupational rhinitis may occur earlier than the asthma after sensitization to CRM-derived allergens, and that CRM-derived allergens may be important factors in the development of both occupational rhinitis and asthma in farmers cultivating citrus fruits.…”

Have the prevalence and incidence of occupational asthma and rhinitis because of laboratory animals declined in the last 25 years?

“…In cross-sectional and longitudinal studies on workers exposed to LA, OA, and OR tended to occur within the first 2-3 years of exposure (8,10,16,17,25). As workrelated respiratory symptoms may have induced affected workers to leave their jobs (healthy worker survivor effect) (34), studies with a longer duration of exposure may show a lower prevalence of symptoms.…”

“…In one study exposure to which LA was not specified, but they were small mammals used in a pharmaceutical company (9). Exposure to one animal only was found in six studies: to a rat in four (17)(18)(19)21) and a mouse in two (Table 1) (11,18). Positive SPT to common aeroallergens, performed in 12 studies, ranged from 15.6% to 60.0%, median 40%.…”

“…Between 1980 and 2004, 15 prevalence reports studied OA and OR in workers exposed to LA (Table 1) (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). The participation rate ranged from 61% to 100%, median 77-78%.…”

“…To investigate trends in the prevalence and incidence of OA and OR over time, we reviewed the available published literature for both (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27).…”