With the increase in technological capabilities, system designers can imagine new possibilities for Humans to interact with smart systems and delegate some of their tasks to these systems. The interactions and support provided by the systems would be so useful that some authors already propose considering them as symbiotic. The objective of this paper is to examine the ethical risks relevant to designing symbiotic systems in the context of Industry 4.0. These risks are presented and discussed. The paper addresses these risks using the human-machine cooperation approach, which allows a detailed analysis of all the kinds of interactions between humans and machines. Three use cases derived from Industry 4.0 objectives were studied within the framework of the ANR HUMANISM project (Human-Machine cooperation for flexible production Systems). These use cases are detailed to underline the interest of this approach regarding the identification, suppression or mitigation of ethical risks.