[1] Linkoping Univ, Div Pediat, Div Mol & Clin Med, S-58183 Linkoping, Sweden
[2] Linkoping Univ, Dept Mol & Clin Med, Div Environm & Occupat Med, S-58183 Linkoping, Sweden
[3] Karolinska Inst, Inst Environm Med, S-10401 Stockholm, Sweden
[4] Cty Hosp Ryhov, Dept Pediat, Jonkoping, Sweden