Personal Ethics in the supply chain that have a social and environmental impact

Discuss how various roles, or people (individuals) within business and/or supply chain (suppliers) can influence, be influenced, or find themselves in situations considered to be unethical. (in terms of social and environmental impact) I.e. behaviours, transactions, deals, promises, etc. associated with material purchasing and sales

Provide 1 or 2 examples of this (i.e. hypotheticals, or known/real examples are ok)