We continued catalysts evaluation by assessing potential toxicological hazards based on the available data. The pyrophoric nature of Pd/C combined with the flammability of hydrogen gas represents a major safety concern. This is circumvented in the Ni foam system, as there is no source for ignition, and the amounts of hydrogen gas produced during operation are low. The use of the Ni foam system also avoids the transportation and storage of hydrogen gas, improving the safety of the overall process. While the Ni foam does raise significant concerns related to skin sensitization (H317) properties and potential organ damage upon prolonged or repeated exposure (H372), it remains a minor issue in a safe laboratory environment where exposure can be kept to a minimum. Under the acidic reaction conditions, NiCl2 or NiSO4 salts may be formed (Supporting Information, Section S3.4). NiCl2 is formed when an HCl (aq) solution is used in the Ni foam activation step. The replacement of this acid by H2SO4 enabled us to avoid the formation of Cl2 and NiCl2. As a result, NiSO4 is formed instead, which poses a lower risk than NiCl2. The degree of loss of Ni from the system is very low, as demonstrated under continuous operation. Palladium is generally classified without any major hazards according to ECHA classifications. However, it's important to acknowledge that palladium is produced or imported in smaller quantities in Europe compared to nickel, and the registration requirements for palladium are less stringent. The main risks associated with palladium arise from its pyrophoricity, and certain manipulation precautions are necessary to avoid accidents and exposure.