It is not what I think, it is what visual evidence available suggest. To say anything concret we need undisputable evidence. 
The visual evidence available in public media suggest a higher level of doubt about the use of chemical weapons.

It may be any other industrial toxic chemical which is capable of producing death and similar effect. There are many industrail chemicals 
whose symptoms can be easily confused with taht of chemical wepans.

Now I am counting on the analysis of the sample collected by UN Inspectors. In the blood of the victims there will be metabolites of chemical wepans used. Similary on soil too. In TV they were showing the container (metallic body) weapns that was fired.analysis of swap sample from those metallic body will also help finding the type of chemical used. 

I hope  UN experst will use their knowledge in fullest. Sometime pseudo expert can produce different results.