(1) “Controlled substance” means that term as defined in section 7104 of the public health code, Act No. 368 of the Public Acts of 1978, being section 333.7104 of the Michigan Compiled Laws.

    (2) “Individual abuser” means an individual who uses a controlled substance that is not obtained directly from, or pursuant to a valid prescription or order of, a practitioner who is acting in the course of the practitioner’s professional practice, or which use is not otherwise authorized under article 7 of the public health code, Act No. 368 of the Public Acts of 1978, being section 333.7101 to 333.7544 of the Michigan Compiled Laws.

    (3) “Level 1 participation” means participating in illegal marketing of 650 or more grams of a mixture containing a specified controlled substance, or of 16 or more pounds or 100 or more plants of marihuana.

    (4) “Level 2 participation” means participating in illegal marketing of 225 or more grams, but less than 650 grams, of a mixture containing a specified controlled substance, or of 8 or more pounds or 75 or more plants, but less than 16 pounds or 100 plants, of marihuana.

    (5) “Level 3 participation” means participating in illegal marketing of 50 or more grams, but less than 225 grams, of a mixture containing a specified controlled substance, or of 4 or more pounds or 50 or more plants, but less than 8 pounds or 75 plants, of marihuana.

    (6) “Level 4 participation” means participating in illegal marketing of less than 50 grams of a mixture containing a specified controlled substance, or of 1 or more pounds or 25 or more plants, but less than 4 pounds or 50 plants, of marihuana.