2014 http://informahealthcare.com/jas ISSN: 0277-0903 (print), 1532-4303 (electronic) J Asthma, 2014; 51(1): 75–78 ! 2014 Informa Healthcare USA, Inc. DOI: 10.3109/02770903.2013.843097 ENVIRONMENTAL DETERMINANTS Cat, dog and house dust mite allergen levels on children’s soft toys Francis Fu-Sheng Wu, MD 1,2,3 , Mei-Wen Wu, MA 4 , Ming-Hui Ting, BSc 1 , Julian Crane, FRACP 3,4 , and Rob Siebers, FSB 3,4 1 Show Chwan Memorial Hospital, Changhua City, Taiwan, 2 Affiliated Hospital of Jining Medical University, Jining, Shandong, China, 3 School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand, and 4 Changhua Christian Hospital, Changhua City, Taiwan Abstract Objective: Children’s soft toys are known to harbour house dust mite (HDM) allergens, but little is known whether they harbour cat or dog allergens. The objective of the study was to measure cat (Fel d 1), dog (Can f 1) and HDM allergens on children’s soft toys. Methods: Dust was collected from 40 children’s soft toys and their mattresses. Data were collected on pet ownership. Dust samples were analysed for Fel d 1, Can f 1, Der p 1 and Der f 1 by enzyme- linked immunosorbent assay (ELISA) and results are expressed as median levels with inter- quartile ranges. Results: Thirty-five (87.5%) soft toys had detectable Fel d 1 levels (median: 0.73 mg/g; inter-quartile range: 0.26–2.56 mg/g) while 34 (85%) had detectable Can f 1 levels (1.20 mg/g; 0.53–2.68). Correspondingly, 32 (80%) mattresses had detectable Fel d 1 levels (0.18 mg/g, 0.07–1.01) while 34 (85%) had detectable Can f 1 levels (0.50 mg/g; 0.33–1.06). All mattresses and soft toys had detectable HDM allergen (Der p 1 þ Der f 1) levels with soft toys containing about three times higher levels than mattresses. In homes with cats (n ¼ 10) Fel d 1 levels were higher on soft toys than homes without cats (2.49 versus 0.48 mg/g; p ¼ 0.0009). In homes with dogs (n ¼ 25) Can f 1 levels were generally higher on soft toys (1.38 versus 0.63 mg/g; p ¼ 0.10). Conclusions: This study has shown that soft toys can harbour cat and dog allergen as well as HDM allergens, some with very high levels. Cat and dog ownership resulted in higher Fel d 1 and Can f 1 levels on soft toys and mattresses. The levels of Fel d 1, Can f 1 and HDM allergens on soft toys could be of importance to sensitized asthmatic children. Keywords Allergen, asthma, cat, children, dog, house dust mite, toys History Received 23 April 2013 Revised 1 September 2013 Accepted 5 September 2013 Published online 29 October 2013 Introduction Many children around the world have soft toys that they play and sleep with. Soft toys are a known source of house dust mites (HDMs) and their allergens [1,2]. In susceptible individuals HDM allergens induce IgE-mediated sensitization that is associated with the development of asthma and asthma symptoms [3,4]. After HDM, exposure to cat and dog allergens is the next most common in the indoor environment. Various studies have shown high levels in homes with cats and dogs, but also in the indoor environment where there are no animals present [5,6]. Cat (Fel d 1) and dog (Can f 1) allergens are aerodynamic and can be transported on clothing into animal-free areas [7], even in cat-free areas such as the Antarctic [8]. As for HDM, sensitization to cat and dog allergens is strongly associated with asthma [5]. As children often sleep with soft toys close to their airways, any allergens present thereon could be a potential problem for sensitized asthmatics. Except for HDM allergens, little is known regarding cat and dog allergen levels on soft toys. In one study, Fel d 1 levels of 4 8 mg/g were found on two cushion-like toys and Can f 1 levels 4 1 mg/g were found on most cushion-like toys [6]. In another study Fel d 1 levels ranged from less than 0.1 to 3.7 mg/g on nine soft toys in day nurseries in Marseilles, France [9]. To our knowledge, no studies have examined dog allergen levels from soft toys in the domestic environment. This study evaluated exposure to Fel d 1 and Can f 1 from children’s soft toys and mattresses from 40 domestic homes in Changhua City, Taiwan and examined whether mattress and soft toy allergen levels were related. Additionally, we also measured the HDM allergens Der p 1 and Der f 1, as both these allergens from the HDM species, Dermatophagoides pteronyssinus and D. farinae, are prevalent in the indoor environment in Taiwan [10]. Materials and methods Subjects Staff members of the Show Chwan Memorial Hospital, Changhua City, Taiwan with at least one child under 12 years of age were invited to participate in the study. Forty families were recruited. The main inclusion criterion was that the child had a soft toy that he/she regularly slept with. The study protocol was explained and informed written consent obtained. The study was approved by the Show Chwan Memorial Hospital Ethics Committee. Correspondence: Assoc Prof R. Siebers, School of Medicine and Health Sciences, University of Otago, PO Box 7343, Wellington South, Wellington, New Zealand. E-mail: rob.siebers@otago.ac.nz J Asthma Downloaded from informahealthcare.com by Wellington Medical Library on 01/23/14 For personal use only.