About 30 children and adult guests at Des Moines’ downtown Marriott Hotel were taken to area hospitals this morning after a mishap with pool chemicals sent fumes through one floor of the building. Marketing manager Leigh (lee) Murray says it happened about mid-morning today.Workers in the pool area called 911 right away and closed the pool, and EMS people arrived quickly. Murray says you can smell a trace of the fumes that sickened some hotel guests.Fire, ambulance, police and other official vehicles surrounded the hotel, which is just a few blocks from Vets Auditorium in downtown Des Moines, and more than a dozen guests were taken to local hospitals after complaining of breathing problems from the fumes. She says the first concern is that workers and guests were okay, some were taken to the hospital and the fire chief didn’t think any were serious. Des Moines Fire Chief Ron Wakeham says doors were blocked off immediately after HAZMAT crews arrived, and nobody was allowed into the hotel. He says they don’t care who leaves, but can’t let anyone in or they’ll lose count of how many patients must be monitored. The chief says the fumes resulted from a chemical reaction when strong pool chemicals were mixed. The chemicals are apparently concentrated chlorine and muriatic acid, used in cleaning.