Transcript for Toxic gases blamed for American family death in Mexico

story. We begin with investigators beginning to unravel a mystery in Mexico. Autopsy results from a family from Iowa, it shows they inhaled toxic gas while insaid their vacation condo and erielle reshef has been on this story. She has more now. Erielle, good morning. Reporter: Good morning to you, Dan and Adrienne. While the autopsy results have been revealed there are still so many questions this morning. Authorities now zeroing in on exactly what inside that condo killed this family of four. Is this morning, new images as investigators comb the scene and test the air inside a condo in Mexico. Trying to identify the mysterious gas that killed a family of four while on vacation. The bodies of Kevin sharp, his wife, Amy and their children sterling and Adrianna discovered in their condo Friday, days after they fell out of touch with friends and family and missed their flight back home. Their plans were to go to danville to watch the many Spartans play in the playoff games. When we did not hear from them after that, then we knew something was wrong. Reporter: Panicked loved ones later learning the worst. Overnight, Mexican officials ruling the cause of death asphyxiation by inhalation of toxic gases. It's something that obviously is just overwhelmed all four of them. Typically with carbon monoxide poisoning you start to get woozy and many times people open a door or window and it just goes away. Reporter: The sharps not the first family sickened by a dangerous substance during a stay abroad. In 2015 this family wound up in intensive care after a poisonous pesticide leaked that their vacation villa in St. John. It really damage your nervous system and can cause long-term and short-term neurological problems and brain damage. Reporter: They survived but with life altering injuries. After months of investigation, the company that applied those pesticides was fined $10 million. Mexican authorities say they're still testing to identify the deadly substance in the sharps' condo and expect those within the next ten days. While it's unclear what gas may have caused this, experts say they recommend traveling with one of those portable carbon monoxide detectors. Really. Because some place, some countries don't regulate this and some hotel rooms and condos may not have one. Another thing to worry about. Seriously. Another thing to take with you when you travel. Let's get it back to Sam for

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