A Berkeley man is trying to get authorities in Thailand to get to the bottom of his wife's mysterious death. 33 year old Soraya Vorster was working as a tour guide in Chiang Mai in January. It's a job she has done before. Tony Pandola says he and his wife were very familiar with the area. After eating dinner with a colleague Vorster and her friend came down with what they thought was food poisoning. Her friend recovered but Vorster died. Since her death six more people have died in the same region with similar symptoms. Everyone except Vorster had ties to one hotel in Chiang Mai. A New Zealand television show is reporting a chemical used to kill bed bugs caused the deaths. But Pandola says that doesn't explain why his wife died. He plans to pressure investigators to keep looking for the cause, hoping no one else has to experience the death of a loved one.