For these reasons, the Court concludes that Section 313(d)(1) permits the Agency to add categories of chemicals to the TRI list, where appropriate, without demonstrating that each individual chemical meets the statutory criteria.
The second issue is whether EPA had sufficient evidence and provided a reasoned explanation for listing the diisocyanates category and IPDI, 2,2,4-TMDI and 2,4,4-TMDI as part of that category. Resolution of this issue centers upon the parties' opposing interpretations of extraordinarily complex scientific evidence. We are thus guided by the advice given by our Court of Appeals in NRDC, 824 F.2d at 1216, that it is "not for the judicial branch to undertake comparative evaluations of conflicting scientific evidence." This Court must not undertake an independent review of EPA's scientific judgments; our inquiry focuses only on whether the Agency has met the statutory requirement for "sufficient evidence."
CMA argues that EPA was arbitrary and capricious because there is no data in the record specifically on 2,2,4-TMDI or 2,4,4-TMDI, and the only study on IPDI did not find chronic pulmonary irritation. Moreover, argues CMA, the studies relied upon by the Agency to list the three chemicals are based on diisocyanates with different physical and chemical properties than IPDI, 2,2,4-TMDI and 2,4,4-TMDI. Thus, concludes CMA, EPA simply "speculated" that IPDI, 2,2,4-TMDI and 2,4,4-TMDI would cause the same effects as the tested chemicals.
EPA explains that to support the listing of both the diisocyanates category and the individual chemicals that comprise it, the Agency reviewed a number of studies of individual diisocyanates. The studies showed that six chemicals with the diisocyanate structure caused pulmonary irritation as a result of inhalation, including such effects as coughing, difficulty breathing, and death. EPA argues that the six chemicals showed these effects despite differences in chemical structure, physical state, molecular weight and vapor pressure. From this evidence EPA concluded that their toxicity was due to the common characteristic shared by the six chemicals, namely, presence of the diisocyanate portion of the molecule, and that this toxicity occurs despite the differences in their other chemical and physical characteristics. 59 Fed. Reg. 61,453-54. Given this finding, EPA concluded that other chemicals with the diisocyanate structure could also reasonably be anticipated to cause pulmonary irritation because, despite difference in various characteristics, they each share the key characteristic: the diisocyanate portion of the molecule. 59 Fed. Reg. 61,453; Response to Comments at 48-49; 51-52. Thus, EPA listed the diisocyanates category, which included 20 individual chemicals, each with the diisocyanate structure.
In short, the Agency believes that IPDI, 2,2,4-TMDI and 2,4,4-TMDI are properly part of the diisocyanates category because all three contain the diisocyanate structure. Moreover, although IPDI, 2,2,4-TMDI and 2,4,4-TMDI have varying physical and chemical characteristics, comparing the three diisocyanates to the six diisocyanates discussed in the studies shows that their characteristics fall within the ranges created by the six tested diisocyanates. The Agency provides extensive scientific evidence for this claim. See EPA MSJ (CMA) at 47-49 and sources cited therein.
Upon review of the administrative record, the Court concludes that the Agency was not arbitrary and capricious in listing the diisocyanates category or including IPDI, 2,2,4-TMDI and 2,4,4-TMDI as part of the category. With respect to the category listing, EPA clearly has sufficient evidence to support the listing, and CMA offers no substantive argument that the diisocyanates category is improperly listed on the TRI.
The same conclusion applies to the three individual chemicals. While none of the studies relied on by EPA specifically involved IPDI, 2,2,4-TMDI or 2,4,4-TMDI, EPA has provided a reasoned explanation for their inclusion in the category: they all possess the diisocyanate structure, which is most likely the source of the chemicals' toxicity. Moreover, EPA's explanation was documented fully in the record. CMA believes EPA has wrongly analyzed available scientific data, and CMA has vigorously attacked EPA's scientific conclusions (i.e., arguing that because the three chemicals have different chemical, physical and molecular make-ups than the tested chemicals they should not be part of the category). But CMA has failed to show that EPA's conclusions are unreasonable, and it is certainly not the job of this Court to make an independent evaluation of the scientific evidence.
Given the record before the Court, EPA had "sufficient evidence" to conclude that the diisocyanates category should be listed on the TRI and that IPDI, 2,2,4-TMDI and 2,4,4-TMDI should be listed as part of the category.
CMA challenges the Agency's listing of 2,6-Dimethylphenol ("2,6-DMP"),
arguing that the two studies relied on by EPA were inadequate to meet the statutory standard. The issue reduces itself to whether EPA may rely on two Russian studies conducted in the 1960s to support its listing of 2,6-DMP.
CMA contends that EPA improperly relied upon the Russian studies because they do not provide a sufficient basis for evaluating human health hazards. CMA notes that documents in the administrative record state that confidence in the 2,6-DMP studies is low because details of the experiments are not available. For example, the Russian studies did not provide information about (1) animal strain, (2) number of animals tested at each dose level, (3) number of animals in the control group, or (4) purity of test articles. Furthermore, in 1990, the Interagency Testing Committee ("ITC") concluded that there was "insufficient evidence" to evaluate both Russian studies.
CMA concludes that without this missing information, it is not possible to determine if the 2,6-DMP experiments are valid.
The Agency argues that the Russian studies provided sufficient evidence to support the listing. In the proposed rule, EPA explained the findings of those studies:
Oral administration of [2,6-DMP] to rats for 8 months produced histologic lesions . . . in the liver, kidneys and spleen. Another supporting oral study in rats . . . also reported histological lesions in the liver . . . of rats following subchronic oral administration of [2,6-DMP]
59 Fed. Reg. 1810
EPA also claims that it considered confirming toxicological information in the Hazardous Substances Data Bank ("HSDB") file on 2,6-DMP. The HSDB is a peer-reviewed database maintained by the National Library of Medicine on the toxicology of potentially hazardous chemicals.
The Agency argues that CMA's list of the studies' alleged shortcomings conveniently ignores key details about the studies which have been reported. The reports on these studies reveal the number of animals tested, the method of dosing, the dosage levels and duration, and the existence of control groups. EPA stresses that the reports reveal that "pronounced" effects on the liver and kidneys resulted at "relatively low dose levels." 59 Fed. Reg. 61,455. More importantly, says EPA, while the Russian studies might not be ideal, no study undertaken in the last 25 years has cast doubt on their results.
Furthermore, EPA acknowledged in its Response to Comments that the absence of information on some of the details of the two studies had led the ITC to characterize the studies as meriting only "low confidence." EPA's position, however, is that although more detail regarding the design of the studies would be desirable for the type of quantitative analysis undertaken in a risk assessment under other statutes, sufficient detail was available for EPA to make the qualitative analysis involved in the hazard assessment required under Section 313 of EPCRA. See 59 Fed. Reg. at 61,455 (col. 1); Response to Comments at 58, 208. The Agency argues that a "low confidence" rating is very different from a "no confidence" rating, and that the Agency does have some confidence in the studies, as evidenced by its use of them in other contexts. For example, EPA uses these studies as evidence of the potential for adverse human health effects in proposing testing for other toxicity endpoints under TSCA. In addition, although the Agency has not set a Reportable Quantity for 2,6-DMP under Section 102 of the Comprehensive Environmental Response, Compensation and Liability Act of 1980 ("CERCLA"), 42 U.S.C. § 9602, EPA used the two Russian studies to prepare a Health and Environmental Effects Profile of 2,6-DMP for purposes of setting a Reportable Quantity of 100 pounds of this substance. In sum, it is EPA's position that while the studies may have been less than ideal, they provided sufficient evidence to justify the listing of 2,6-DMP.
Based on its evaluation of the Russian studies and information from the HSDB, EPA concluded that there was sufficient evidence to list 2,6-DMP based on hepatoxicity (toxicity to the liver) and nephrotoxicity (toxicity to the kidneys). Id.
The Court concludes that in light of the relevant data that is known about the Russian studies, the fact that their results have not been invalidated in 25 years, consideration of the HSDB, and the substance of EPA's explanation for its listing decision, the Agency's decision to list 2,6-DMP was not arbitrary and capricious. While it would be desirable to know more about the Russian studies, EPA has provided a reasonable explanation for why they are sufficient to meet the statutory standard and justify listing 2,6 DMP on the TRI.
Plaintiff CMA argues that EPA was arbitrary and capricious in listing 2-bromo-2-nitropropane-1,3-diol ("Bronopol"). Bronopol is a water-soluble, white, crystalline solid that acts as a broad-spectrum antimicrobial agent and has a wide range of industrial uses, including as a biocide for paper treatment, recirculating cooling systems, air scrubbers and air conditioning systems. Bronopol is used to prevent bacterial spoilage of latex paints, water-based printing inks and fountain solutions, and adhesives.
EPA added Bronopol to the TRI list based primarily upon a two-year study in rats which showed irritation of the gastrointestinal tract, ulceration and stomach lesions. 59 Fed. Reg. 1800. The Agency also summarized the results of four other animal studies that confirmed the two-year study's finding of "severe" effects on the gastrointestinal tract following ingestion of Bronopol. Id.27 EPA concluded that the five studies together showed sufficient evidence to warrant listing on the TRI. 59 Fed. Reg. 61,450.
Plaintiff CMA's primary argument is that EPA was arbitrary and capricious when it listed Bronopol because the three effects cited by EPA--lesions of the gastrointestinal tract, inflammation of the gastrointestinal tract and a thickening of the walls of the gastrointestinal tract--are acute, not chronic, as required by the statute.
The Agency does not dispute that Bronopol can cause acute health effects. Indeed, in the rulemaking, EPA acknowledged that Bronopol causes gastric effects after short-term exposure to high doses (i.e., an "acute" response). But, EPA argues, it also found that gastric effects appeared after long-term exposure to low-doses (i.e. a "chronic" response). EPA says that after examining the relative dose levels, duration of treatment, and the incidence and types of effects found in the studies, it concluded that the evidence that Bronopol caused certain acute effects did not negate its conclusion that Bronopol also caused chronic human health effects. 59 Fed. Reg. 61,450. In the final rule EPA explained:
Although the Agency agrees with the comment that [bronopol] presents a moderate acute hazard, EPA does not agree that the chemical is not a chronic toxicant. The effects noted in both acute and chronic studies, cited in the proposed rule, indicate irritation due to exposure in the compound. However, differing expressions of irritation are obtained depending upon the level of material to which the test animals were exposed and the duration of the exposure. In the acute studies cited in the proposed rule, the acute gastric effects were seen at relatively high doses. In the chronic studies, cited in the proposed rule, the effects . . . were noted following repeated oral exposure to lower doses of [bronopol].
EPA contends that CMA is incorrect that a chemical can cause only acute toxic effects or chronic toxic effects, but not both. In EPA's view, a finding of acute toxicity and a finding of chronic toxicity are not mutually exclusive. Thus, when CMA points to various acute toxicity studies to prove that Bronopol does not exhibit chronic toxicity, it does not disprove the findings of the chronic two-year study, and cannot disprove those findings unless one assumes that a chemical cannot exhibit both acute and chronic toxicity.
In consideration of these arguments, the Court concludes that EPA was not arbitrary and capricious in listing Bronopol. Put simply, CMA has offered little to disprove the findings of the primary study relied upon by the Agency. EPA has certainly provided a reasoned explanation for its conclusion that Bronopol causes chronic health effects. See EPA MSJ (CMA) at 73-78 and citations to the record therein.
EPA has also adequately documented its decision-making process with respect to listing Bronopol. EPA scientists did not, as CMA suggests, review only the Tox-One-Liner database for Bronopol. In the Response to Comments, EPA said:
Although the 1988 Tox-One-Liners were used as part of the Agency's evaluation of the toxicity of a candidate chemical, a number of other sources were also used. These include . . . data evaluation records for studies used in support of listing. Therefore, evaluations of the toxicity of individual chemicals has been made on the entire body of available information on the specific chemicals and did not rely on the 1988 Tox-One-Liners data base.