Boron
Warning! According to the classification provided by companies to ECHA in CLP notifications this substance is harmful if swallowed, causes serious eye irritation, is harmful if inhaled and may cause respiratory irritation. Ingestion or contact with an excessive quantity of boron may harm the health of children by damaging their reproductive systems.
Source and more information: https://echa.europa.eu/substance-information/-/substanceinfo/100.216.729
