Exponeringsrisker i samband med inhalationsbehandling av häst

Sammanfattning: Bronchiolitis is a common performance decreasing disease in horses (Bracher et al, 1991¸Dixon et al, 1995) Its medical treatment includes inhalation therapy with corticosteroids and b2-adrenoceptorer stimulators. Use of both these medicines is prohibited for sport horses and athletes. Because the facemasks used for inhalation therapy are not airtight, there is a risk for leakage of these medicines. We wanted to see if cross exposure of nearby horses can result during normal recommended treatment of a horse, and assess if this could result in doping positive urine sample from the person treating the horse and from horses in the same airspace. We did a pilot study with four healthy horses. The experiment was divided into four parts. Two of them were done with corticosteroids and two with b2- adrenoceptor stimulators. Both medicines were tested separately with the two different metered dosed inhalers that are most commonly used in Sweden. In each experiment one of the horses was treated while standing in the stable with the three other horses, following which urine samples were collected from all four horses as well as from the person administering the treatment. Due to economic constraints only samples from the b2-adrenoceptor stimulator experiments were analysed. Following inhalation treatment of a horse using either inhalation mask, detectable levels of b2-adrenoceptor stimulator were measurable on some occasions in the urine of some of the untreated horses and in the person administering the drug. The threshold for doping value of b2-adrenoceptor stimulator in humans was not exceeded in this study. For horses there is a specific doping concentration value for corticosteroids but none for b2-adrenoceptors. This means that if it is possible to detect b2-adrenoceptors in a urine sample, no matter at which concentration, it would be considered doping positive. The results of this study suggest that there is leakage from the inhalation masks sufficient to expose both the person treating the horse, and neighbouring, untreated horses to inhaled medications.