What is the poisonous substance in the lily-of-the-valley?
                                
                                
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                                    3 min read                                
                            
                                Over 30 different cardiac glycosides, including the potent convallatoxin, are the poisonous substances found in the beautiful and fragrant lily-of-the-valley. This plant's deceptive charm hides its significant toxicity, which can pose a serious risk to both humans and animals if ingested.