Materials and Methods Population Sampling. Nine hundred equestrian instructors were selected randomly from a database of approximately 2,500 certified riding instructors identified through the United States Dressage Federation and the Certified American Horsemanship Association organizations and representing 47 states of the United States to receive a self-administered questionnaire. The sample was contacted via mail with a cover letter and 5-page questionnaire regarding respiratory symptoms, participation in work, indoor or outdoor arena use, dust control, and smoking habits. 348 instructors returned the survey for a response rate of 38%. Work was defined as duties or tasks involving student instruction, horse exercise/training, and barn/facility management and operations. Symptom descriptions for asthma, chronic bronchitis and pneumonia were adapted from the National Institute for Occupational Safety and Health respiratory disease questionnaires. All respiratory disease data were self-reported. Current smokers were defined as daily smokers. Number (or fraction of) packs of cigarettes smoked per day, age of smoking onset, and years smoked for former and current smokers were included. Statistical Analyses. Rates of symptom reports of asthma, chronic bronchitis, noninfectious rhinitis and pneumonia were compared against type of working facility (indoor or outdoor arena). Arena surface materials and dust control agents were also examined. Average length of time worked in the horse industry, involvment with horses in any capacity, paid or unpaid, number of horses trained, and hours spent at the horse facility were compared between those respondents with asthma, chronic bronchitis, pneumonia, and noninfectious rhinitis and those respondents not reporting these problems. Further analysis included logistic regression with all four respiratory conditions as the dependent variables and exposure variables and personal risk factors as the independent variables. Results and Discussion Questionnaires were completed for 48 male and 289 female instructors ranging in age from 15 to 79 yr. Women accounted for 83%. The median age of the respondent population was 36 yr. Ninety-three percent were instructors, 3.2% were owners, 3.2% were trainers and 2% grooms and stable hands. Forty-five percent were self employed and 55% were employees. Sixteen percent did not have health insurance. The average length of time the instructors had worked with horses was 10 yr. Instructors worked a mean of 10 hr per day and a median of 7 hours at the horse facility, with a range of 0 to 24 h. The average number of horses trained per instructor was six. Nearly half (46%) of the equestrian instructors used an indoor arena as their primary working facility. Fifty percent had one or more college degrees, 9% had a master’s degree and 1% had received a doctoral degree. Ten percent of respondents were current smokers, which is less than half the 23% rate in the general population. Bronchitis Symptoms. Bronchitis was defined as the presence of cough most days for as much as 3 mo per year or phlegm or mucous production 4 or more days per week. No relationship was found between the occurrence of chronic bronchitis symptoms and age or the number of years worked in the industry (P>0.05). There was a positive association between reported symptoms of chronic bronchitis and indoor arena work (P<0.05). A positive relationship was also seen between bronchitis symptoms and smoking (P<0.05). The overall prevalence of chronic bronchitis among the equestrian instructor population was 35%: 33% among nonsmokers and 55% in smokers. Non-smokers working indoors had a prevalence of chronic bronchitis symptoms of 40% while those working outdoors had a 26% prevalence for an odds ratio of indicating a moderate relationship between environment and symptom prevalence. Comparing smokers, the prevalence of symptoms was 67% for those working indoors, versus 44% for outdoor work for an odds ratio of 2.5. Overall, equestrian instructors who used an indoor as a primary working facility were nearly twice as likely to report chronic bronchitis symptoms as those who use an outdoor arena with an odds ratio of The prevalence of bronchitis (35%) for all instructor categories was high compared to the 5.4% reported in the general American population. Asthma. Thirty nine percent of all respondents reported “ever wheezing”, usually associated with a cold or respiratory infection. The prevalence of reported asthma was 17% and physician-diagnosed asthma was 14%. Both are slightly elevated compared to current reports in the general American population (6-12%) or lifetime rate of 10%. Sixteen percent reported use of medication for asthma, and one third of those used it daily. Rhinitis Symptoms. Rhinitis or nasal inflammation may be caused by allergy, irritants or infection. The prevalence of rhinitis in the general population is estimated at 23%. Rhinitis was defined as frequent or repeated episodic runny or stuffy nose or postnasal drainage, unassociated with fever or systemic symptoms. The equestrian instructors reported a prevalence of 27% for perennial rhinitis, and 49% with episodic symptoms in the prior year. Symptom survey could not distinguish between allergic or irritant rhinitis, but 15% of respondents reported “hay fever” as a cause of their nasal symptoms. Pneumonia. Twenty-three percent of the respondents had a history of pneumonia, and 25 percent had been hospitalized for it. For this relatively young group, pneumonia appears to be a frequent occurrence. There was an association between report of past pneumonia and the number of years instructors worked with horses (P<0.05), but it is not clear if there is a actual relationship between the years worked with horses and disease occurrence. Instructors with a history of pneumonia were an average of 4 yr older than those individuals who had no such history. Smoking Habits. The prevalence of current smoking among all participants was 10%. Fifteen percent reported being a past smoker. Among smokers, the median number of cigarettes smoked per day was 15 and the average number of years smoked was 25 yr. As expected, there was a positive association (P<0.05) between bronchitis symptoms and smoking. The combination of working indoors and smoking increased the prevalence of chronic bronchitic symptoms. Arena Flooring Materials. Arena flooring materials were also examined as potential risk factors for the development and occurrence of bronchitis symptoms. Seventy-one percent of the riding facilities used sandy soil as a primary surface material, while 40% employed clay, 21% applied wood products, 7% used rubber and 6% applied tan bark. No association (P>0.05) or trends were observed with respect to the type of flooring currently in use and prevalence of bronchitis. Historical review of past flooring exposure was not attempted. Dust Control Agents. The use of dust control agents in indoor arenas and the prevalence of bronchitis symptoms were also investigated. The primary dust suppression agent used by respondents was water (58%), while 7% added chemicals, 6% incorporated soiled bedding/manure and 3% used other suppressants (Figure 1). Sixty percent of instructors reported some dust control efforts. There was no association (P>0.05) observed between the prevalence of bronchitis and dust control agent use in indoor arenas. National Survey of Respiratory Disorders in Equestrian Instructors A. M. Swinker* and M. L. Swinker, *Penn State University, Dairy and Animal Science, University Park, PA 16802, East Carolina University, Brody School of Medicine, Greenville, NC Conclusion This study suggests that a large percentage of riding instructors have respiratory symptoms that could be related to work exposures and that could be further evaluated medically. It could not be determined from this study whether the rhinitis reported by 27 to 49% of the equestrian instructors was due to allergy, or from direct nasal irritation by dusts, chemicals, or gases. Further evaluation is needed to characterize the nature of rhinitis in the equestrian instructors. The reports of bronchitic symptoms in nonsmoking instructors who work in a dusty indoor environment suggest possible impairment in respiratory function related to this exposure. Formal pulmonary function testing or spirometry might be performed to measure airflow and volumes, both before and after dust exposure. Such studies could demonstrate whether the asthma or bronchitic symptoms reported are associated with changes in these respiratory parameters; and whether changes are reversible after removal from dust exposure. Agricultural dusts include both organic and inorganic components. The organic component is thought to account for most agricultural respiratory disease, manifested as asthma and bronchitis, and reported to develop in 5 to 20% of agricultural workers. Personal respiratory protection (eg., dust mask or kerchief) is recommended for instructors while working indoors to minimize exposure to airborne dust: and when possible, supplemented with such controls as ventilation and dust suppression. Further investigation is warranted to characterize the nature and pathogenicity of the specific fractions of riding arena dusts, as well as to find effective and practical methods of dust control. Introduction In humans, pulmonary diseases caused by dust are a significant source of occupational morbidity and mortality. Dust generated by agriculture is a recognized hazard. It is well-documented that farmers, their families and other agricultural workers have an increased risk for the development of dust-induced respiratory diseases and syndromes. Agricultural work generally results in exposure to combinations of inorganic and organic dusts. Smoking is a major risk factor in the development of chronic bronchitis and contributes a synergistic effect to agricultural or other dust exposure. During riding and training activities, arena surfaces are agitated by the use of one or more horses resulting in airborne dust. Dust loads increase when animals are being moved, handled, and fed and instructors and trainers are exposed to this dust for many hours daily. Working in areas that are in confined or enclosed areas can intensify dust concentrations.