 Lung inflammation: The investigators will measure fractional exhaled nitric oxide FENO in participants 9 yrs as a marker of allergic lung inflammation. Monitoring FENO is simple and non-invasive with the use of a hand held small equipment. FENO will be measured online by the single breath technique according to published guidelines ref and manufacturers instructions, with a NIOX MINO. FENO will be recorded as mean value from two successive reproducible readouts. FENO data will be given as p.p.b. NIOX MINO uses IR communication for transfer of participant data to a PC using the software NIOX MINO Data Manager. FENO is usually high in individuals with current allergic asthma or rhinitis. 