(a) Drug testing and rehabilitation

(1) In general
Nothing in this chapter shall be construed to prohibit a State from testing participants in programs, activities, or services carried out or provided under this chapter for controlled substances. A State that conducts such testing shall inform the participants who test positive for any of such substances about the availability of treatment or rehabilitation services and refer such participants for appropriate treatment or rehabilitation services.

(2) Administrative expenses
Any funds provided under this chapter expended for such testing shall be considered to be expended for administrative expenses and shall be subject to the limitation specified in section 9907(b)(2) of this title.

(3) Definition
In this subsection, the term "controlled substance" has the meaning given the term in section 802 of title 21.

(b) Child support services and referrals
During each fiscal year for which an eligible entity receives a grant under section 9907 of this title, such entity shall—

(1) inform custodial parents in single-parent families that participate in programs, activities, or services carried out or provided under this chapter about the availability of child support services; and

(2) refer eligible parents to the child support offices of State and local governments.