Tohoros 2:4

First- and second-degree impurity in trumah are unclean and convey impurity. Third-degree impurity invalidates but doesn’t convey impurity. Fourth-degree impurity may be eaten in a stew with sanctified food (kodesh).

Tohoros 2:5

First-, second- and third-degree impurity in kodesh are unclean and convey impurity. Fourth-degree impurity invalidates but doesn’t convey impurity. Fifth-degree impurity may be eaten in a stew with kodesh.