Can a sago palm needle poison a human?

Yes. Sago cycad seeds contain highly poisonous compounds. Consumption of cycad seeds has been implicated in the outbreak of Parkinson's Disease-like neurological disorder in various locations in the Pacific such as Guam. Highly toxic cycasin and BMAA compounds are found in all parts of the plant, but are most concentrated in the seeds. These must be removed through extended processing before any part can be safely eaten. Consumption of any part of the plant can result in liver failure or neurologic disease in domestic animals.