What is the test for determining whether a workplace environment is hostile or abusive?

[W]hether an environment is 'hostile' or 'abusive' can be determined only by looking at all the circumstances. These may include the frequency of the discriminatory conduct; its severity; whether it is physically threatening or humiliating, or a mere offensive utterance; and whether it unreasonably interferes with an employee's work performance. The effect on the employee's psychological well-being is, of course, relevant to determining whether the plaintiff actually found the environment abusive. But while psychological harm, like any other relevant factor, may be taken into account, no single factor is required.

Harris v. Forklift Systems, Inc., 510 U.S. at 23.