Actually, you probably have no rights to an increase in salary, even under the circumstances. The fact is that most employment arrangments are what is known as "at will". This means that a company can set the terms and conditions of the workplace much as it sees fit. This includes setting an employee's salary and work duties.That having been said, if your treatment is due to some form of actionable discrimination then that would be illegal. So you may have a claim if your treatment is based on your age, gender, sexual orientation, nationality race, religion, or disability. Also, if your treatment violates the company policy or the terms of a union agreemnt or employment contract, then that too would be against the law.Otherwise, I am afraid that your only option is to continue working for this employer, refuse your additional workload and risk termination, or quit.