Thank heavens it was only a trace amount of ricin.
Less than a pinpoint [of ricin] can kill a human if ingested, injected or inhaled and there is no known cure.
Will they be telling us the name of the very toxic poison?
I THINK you are misreading the article (which is confusingly written).
I believe the "very toxic poison" was quoting what was ORIGINALLY said about the bottles, not what was said when they said there was no Ricin.