APPEAL from an order of the Superior Court of Los Angeles County, Michael C. Solner, Judge. Affirmed. (Los Angeles County Super. Ct. No. BS109343).
The opinion of the court was delivered by: Suzukawa, J.
CERTIFIED FOR PUBLICATION
On April 20, 2007, respondent Office of Environmental Health Hazard Assessment (OEHHA)*fn1 listed di-isodecyl phthalate (DIDP) as a chemical known to cause reproductive toxicity under the Safe Drinking Water and Toxic Enforcement Act of 1986 (Health & Saf. Code, §§ 25249.5-25249.13), commonly known as Proposition 65. Appellant Exxon Mobil Corporation (Exxon) sought a writ of mandate challenging OEHHA's listing. The trial court denied the petition for writ of mandate, and Exxon appealed. Because we conclude that OEHHA did not abuse its discretion in listing DIDP as a chemical known to cause reproductive toxicity, we affirm.
I. Overview of Proposition 65
Californians adopted Proposition 65 through the voter initiative process in November 1986. The provisions of Proposition 65 were subsequently codified in Health and Safety Code sections 25249.5 through 25249.13.*fn2
Proposition 65 requires that, at least once per year, the Governor shall cause to be published "a list of those chemicals known to the state to cause cancer or reproductive toxicity within the meaning of this chapter." (§ 25249.8, subd. (a).) The listing of a chemical triggers two requirements. The first requirement, contained in section 25249.5, prohibits businesses from discharging the chemical "into water or onto or into land where such chemical passes or probably will pass into any source of drinking water." The second, contained in section 25249.6, requires that businesses give "clear and reasonable warning" before exposing individuals to the chemical. (§ 25249.6 ["No person in the course of doing business shall knowingly and intentionally expose any individual to a chemical known to the state to cause cancer or reproductive toxicity without first giving clear and reasonable warning to such individual...."].)
Even after a chemical has been listed, a discharge or release of the chemical is permitted under section 25249.9 if a business can demonstrate that the discharge or release "will not cause any significant amount of the discharged or released chemical to enter any source of drinking water." (Subd. (b)(1).) Similarly, under section 25249.10, a business need not warn of exposure to a listed chemical if it can demonstrate that the exposure "poses no significant risk assuming lifetime exposure at the level in question for substances known to the state to cause cancer, and that the exposure will have no observable effect assuming exposure at one thousand (1,000) times the level in question for substances known to the state to cause reproductive toxicity, based on evidence and standards of comparable scientific validity to the evidence and standards which form the scientific basis for the listing of such chemical...." (§ 25249.10, subd. (c).)
Proposition 65 provides that the Governor "shall designate a lead agency" that "may adopt and modify regulations, standards, and permits as necessary to conform with and implement this chapter and to further its purposes." (§ 25249.12, subd. (a).) The Governor has designated OEHHA as the lead agency charged with implementing Proposition 65.*fn3 (Cal. Code Regs., tit. 27, § 25102, subd. (o); Baxter Healthcare Corp. v. Denton, supra, 120 Cal.App.4th 333, 346.)*fn4
A. The Statute-Section 25249.8
The focus of our inquiry in the present case is section 25249.8 ("the statute"), which governs the listing of chemicals under Proposition 65. As we have said, section 25249.8 requires that the Governor annually cause to be published "a list of those chemicals known to the state to cause cancer or reproductive toxicity within the meaning of this chapter." (§ 25249.8, subd. (a).) A chemical "is known to the state to cause cancer or reproductive toxicity" if
(1) "in the opinion of the state's qualified experts it has been clearly shown through scientifically valid testing according to generally accepted principles to cause cancer or reproductive toxicity," or
(2) "if a body considered to be authoritative by such experts has formally identified it as causing cancer or reproductive toxicity," or
(3) "if an agency of the state or federal government has formally required it to be labeled or identified as causing cancer or reproductive toxicity." (§ 25249.8, subd. (b), italics added.)
Thus, section 25249.8, subdivision (b) of the statute sets out three different ways by which a chemical can be listed. First, a chemical will be listed if the state's "qualified experts"-the Developmental and Reproductive Toxicant (DART) Identification Committee (for reproductive toxicants) or the Carcinogen Identification Committee (for carcinogens) (Regs., § 25102, subd. (c)(1)-(2))*fn5-have determined that the chemical causes cancer or reproductive toxicity. Second, a chemical will be listed if "a body considered to be authoritative" has "formally identified" it as causing cancer or reproductive toxicity. Third, a chemical will be listed if a state or federal agency has required it to be labeled as causing cancer or reproductive toxicity. Our focus in the present case is on the second method, the so-called "authoritative body" provision of section 25249.8, subdivision (b).
Regulations promulgated by OEHHA and its predecessor, the Health and Welfare Agency, identify five agencies deemed "authoritative bodies" for purposes of identifying chemicals known to cause reproductive toxicity within the meaning of section 25249.8. A body is "considered to be authoritative" under this section if "the DART Identification Committee has identified [it] as having expertise in the identification of chemicals as causing reproductive toxicity." (Regs., § 25306, subd. (b).) The National Toxicology Program*fn6-the authoritative body at issue in the present case-is one of the five identified agencies. The others are the U.S. Environmental Protection Agency, the U.S. Food and Drug Administration, the International Agency for Research on Cancer (solely as to transplacental carcinogenicity), and the National Institute for Occupational Safety and Health. (Regs., § 25306, subd. (l).)
The regulations provide that the "lead agency" (OEHHA) "shall determine which chemicals have been formally identified by an authoritative body as causing cancer or reproductive toxicity." (Regs., § 25306, subd. (c).) Further:
(1) A chemical is "formally identified" by an authoritative body when OEHHA determines that "the chemical has been included on a list of chemicals causing cancer or reproductive toxicity issued by the authoritative body; or is the subject of a report which is published by the authoritative body and which concludes that the chemical causes cancer or reproductive toxicity; or has otherwise been identified as causing cancer or reproductive toxicity by the authoritative body in a document that indicates that such identification is a final action." (Regs., § 25306, subd. (d).) Further, the list, report, or document must satisfy regulatory formalities. (Ibid.) It satisfies these formalities if it "specifically and accurately identifies the chemical" and has been (a) "[r]eviewed by an advisory committee in a public meeting, if a public meeting is required," or (b) "[m]ade subject to public review and comment prior to its issuance," or (c) "[p]ublished by the authoritative body in a publication, such as, but not limited to, the federal register for an authoritative body which is a federal agency," or (d) "[s]igned, where required, by the chief administrative officer of the authoritative body or a designee," or (e) "[a]dopted as a final rule by the authoritative body," or (f) "[o]therwise set forth in an official document utilized by the authoritative body for regulatory purposes." (Regs., § 25306, subd. (d)(2).)
(2) "As causing reproductive toxicity" means either that "[s]tudies in humans indicate that there is a causal relationship between the chemical and reproductive toxicity" (Regs., § 25306, subd. (g)(1)), or
"Studies in experimental animals indicate that there are sufficient data, taking into account the adequacy of the experimental design and other parameters such as, but not limited to, route of administration, frequency and duration of exposure, numbers of test animals, choice of species, choice of dosage levels, and consideration of maternal toxicity, indicating that an association between adverse reproductive effects in humans and the toxic agent in question is biologically plausible" (Regs., § 25306, subd. (g)(2)).*fn7
The regulations further provide that OEHHA shall find that a chemical does not satisfy the definition of "causing reproductive toxicity" if "scientifically valid data which were not considered by the authoritative body clearly establish that the chemical does not satisfy the criteria of subsection (g), paragraph (1) or subsection (g), paragraph (2)."
(Regs., § 25306, subd. (h).) If objections are made to a listing decision, OEHHA shall refer the chemical to the DART Committee if it finds that "there is no substantial evidence that the criteria identified... in subsection (g) have been satisfied." (Regs., § 25306, subd. (i).)
FACTUAL AND PROCEDURAL BACKGROUND
Di-isodecyl phthalate, or DIDP, is a substance that is part of a group of chemicals known as phthalates. Phthalates are used primarily to soften and increase the flexibility of plastics. DIDP is used as a plasticizer in a wide variety of polyvinyl chloride (PVC) plastic products, including coverings on wires and cables, artificial leather, toys, carpet backing, and pool liners. It also has limited use in food packaging and handling. Approximately 135,000 metric tons (about 298 million pounds) of DIDP were used in the United States in 1998.
II. The Authoritative Body's Report
A. National Toxicology Program
The National Toxicology Program (NTP) is a federal interagency program that evaluates agents of public health concern. Three agencies form the core of NTP: the National Institute of Environmental Health Sciences of the National Institutes of Health, the National Institute for Occupational Safety and Health of the Centers of Disease Control and Prevention, and the National Center for Toxicology Research of the Food and Drug Administration. (http://ntp.niehs.nih.gov/?objectid=7201637B-BDB7-CEBAF57E39896A08F1BB [as of Jan. 7, 2009]; http://ntp.niehs.nih.gov/?objectid=720163E9-BDB7-CEBA-FB0157221EB4375F [as of Jan. 7, 2009].)
In 1998, NTP and the National Institute of Environmental Health Sciences established the NTP Center for the Evaluation of Risks to Human Reproduction (NTPCERHR) to evaluate the potentially hazardous effects of chemicals on human reproduction and development. NTP-CERHR publishes monographs that assess the evidence that environmental chemicals cause adverse effects on reproduction and development and opine on whether these substances are hazardous for humans. (http://cerhr.niehs.nih.gov/about CERHR/index.html [as of Jan. 7, 2009].) NTP-CERHR monographs have three parts: (1) the NTP Brief on the chemical evaluated, (2) an Expert Panel Report, and (3) all public comments.
B. The Expert Report on DIDP
In 1999, NTP-CERHR initiated a review of seven phthalates, including DIDP. NTP-CERHR assembled an expert panel of scientists (expert panel) to review and evaluate the scientific evidence on the potential reproductive and developmental toxicities of each phthalate. Over 16 months, the expert panel critically reviewed more than 500 documents on the seven phthalates, held three public meetings, and received public comments.
The NTP-CERHR Expert Panel issued its report on DIDP, entitled "NTP-CERHR Expert Panel Report on Di-Isodecyl Phthalate" (the Expert Report), in October 2000. The report discussed five studies, four in rats and one in mice, that evaluated prenatal developmental toxicity following exposure to DIDP. In two of the studies, DIDP was administered to pregnant rats by "gavage," in which a small tube was inserted through the rat's mouth directly into the stomach. Both of these studies showed that fetuses exposed prenatally to DIDP had an increased incidence of skeletal abnormalities, including the growth of extra ribs. Two additional two-generation reproductive toxicity studies, in which female rats were exposed to DIDP through diet, also showed increased mortality rates and decreased birth weight among rat pups exposed prenatally to DIDP.
Based on these studies, the expert panel found that "[t]here are adequate data available in rats to determine that prenatal oral exposure to DIDP results in developmental toxicity." Further, based on toxicokinetic*fn8 studies in rodents, the panel found that "[t]here is adequate general toxicokinetic data for DIDP, consisting of absorption, distribution, metabolism, and excretion, over a range of oral doses in the rat.... While studies of toxicokinetics in humans have not been located, the DIDP toxicokinetic data in rats are consistent with the large body ...