Court Opinion

ID: 5118842
Source: CourtListenerOpinion
Date Created: 2021-10-16 00:00:36.501184+00
Date Added: 2024-06-11T08:22:09.845124
License: Public Domain

Case: 20-30365     Document: 00516057380         Page: 1    Date Filed: 10/15/2021

           United States Court of Appeals
                for the Fifth Circuit
                                                                        United States Court of Appeals
                                                                                 Fifth Circuit

                                                                               FILED
                                                                        October 15, 2021
                                  No. 20-30365                            Lyle W. Cayce
                                                                               Clerk

   Juanea L. Butler, individually and as representative of all others similarly
   situated,

                                                           Plaintiff—Appellant,

                                      versus

   Denka Performance Elastomer, L.L.C.; E. I. DuPont de
   Nemours & Company; State of Louisiana, through the
   Department of Health, incorrectly named as Louisiana State
   through the Department of Health and Hospitals;
   State of Louisiana, through the Department of
   Environmental Quality; Dupont Performance
   Elastomers, L.L.C., formerly known as DuPont Dow
   Elastomers, L.L.C.,

                                                        Defendants—Appellees.

                  Appeal from the United States District Court
                     for the Eastern District of Louisiana
                           USDC No. 2:18-CV-6685

   Before Haynes, Higginson, and Oldham, Circuit Judges.
   Stephen A. Higginson, Circuit Judge:
         In this environmental tort case, Juanea Butler alleges that neoprene
   production from the Pontchartrain Works Facility exposed residents of St.
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                                          No. 20-30365

   John the Baptist Parish, Louisiana, to unsafe levels of chloroprene, which she
   contends may result in a myriad of adverse health conditions including an
   elevated risk of cancer. Butler sued Denka Performance Elastomer and
   DuPont—the current and former owners of the facility—as well as the
   Louisiana Departments of Health (“DOH”) and Environmental Quality
   (“DEQ”) in state court seeking class certification, damages, and injunctive
   relief for various state tort claims.
           Following removal, the district court denied Butler’s motion to
   remand to state court; 1 granted each of the defendants’ motions to dismiss
   because Butler’s claims were either time-barred or failed to state a plausible
   claim; 2 denied in part Butler’s motion for leave to amend as futile; 3 and
   dismissed the amended petition for failure to state a claim. 4 Butler appeals
   each ruling. 5
                                                I.
           DuPont owned and operated the Pontchartrain Works Facility
   (“PWF”) from 1969 until 2015, when DuPont sold the plant to Denka. For
   decades, it is alleged, the plant has emitted unsafe levels of chloroprene into

           1
            Butler v. Denka Performance Elastomer, LLC (Butler I), No. 18-CV-6685, 2019 WL
   92659 (E.D. La. Jan. 3, 2019), reconsideration denied, No. 18-CV-6685, 2019 WL 697164
   (E.D. La. Feb. 20, 2019).
           2
               Butler II, No. 18-CV-6685, 2019 WL 1160814 (E.D. La. Mar. 13, 2019).
           3
             Butler III, No. 18-CV-6685, 2019 WL 2417500 (E.D. La. June 10, 2019), rev’g in
   part, No. 18-CV-6685, 2019 WL 8888172 (E.D. La. Apr. 16, 2019).
           4
               Butler IV, No. 18-CV-6685, 2020 WL 2747276 (E.D. La. May 27, 2020).
           5
            This is Butler’s second appeal. She first appealed a subset of the district court’s
   orders on April 11, 2019, while her motion for leave to amend her complaint was still
   pending. Consequently, and because no final judgment had been entered, this court
   dismissed the appeal for lack of appellate jurisdiction. Butler V, 806 F. App’x 271, 272 (5th
   Cir. Mar. 20, 2020) (per curiam) (unpublished).

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   the air, exposing nearby residents in the vicinity to adverse health effects.
   Though DuPont sold the neoprene manufacturing facilities of the PWF to
   Denka, it retained ownership of the underlying land and buildings.
           On June 5, 2018, Butler filed her initial class action petition in
   Louisiana state court. 6 She complains only of the chloroprene released as a
   result of the facility’s neoprene production, and both the PWF’s owners and
   the state’s alleged failure to regulate those emissions.
           Butler acknowledges that she is not the first to complain about these
   chloroprene emissions. The district court, accepting as true as it must the
   allegations in Butler’s complaint and undisputed by the parties on appeal,
   summarized the relevant background as follows:
                   In December 2015, the Environmental Protection
           Agency (“EPA”) released a screening-level National Air
           Toxics Assessment (“NATA”), and classified chloroprene as
           a likely human carcinogen. EPA’s NATA evaluation suggested
           an acceptable risk exposure threshold for chloroprene: 0.2
           µg/m³; that is, chloroprene emissions should stay below .2
           micrograms per cubic meter to comply with the limit of
           acceptable risk threshold (which is a risk of 100 in one million
           people).
                  The EPA held its first Parish community meeting to
           discuss the potential chloroprene emission issues on July 7,
           2016. At that meeting, a DOH representative advised that
           children should not breathe chloroprene. In August of 2016,
           Denka began 24-hour air sampling every six days. Samples
           collected at five sampling sites are and continue to exceed the
           0.2 µg/m³ threshold. According to Denka’s own sampling

           6
              Butler subsequently amended the class definition in a First Amended Petition,
   also in state court, on June 11, 2018. We refer to the initial and first amended petitions,
   collectively, as “FAP.”

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         numbers for chloroprene concentrations, the average
         chloroprene concentration across all sampling sites from
         August 2016 to March 2017 has ranged from 4.08 µg/m³ to 6.65
         µg/m³.
                 The EPA has noted that, in addition to the high risk of
         cancer from exposure to chloroprene, symptoms include:
         headache, irritability, dizziness, insomnia, fatigue, respiratory
         irritation, cardiac palpitations, chest pains, nausea,
         gastrointestinal disorders, dermatitis, temporary hair loss,
         conjunctivitis, and corneal necrosis.
               The EPA has further detailed that acute exposure may:
         damage the liver, kidneys, and lungs; affect the circulatory
         system and immune system; depress the central nervous
         system; irritate the skin and mucous membranes; and cause
         dermatitis and respiratory difficulties in humans.
                On October 7, 2016, Denka submitted modeling results
         for chloroprene concentrations surrounding the PWF to the
         Louisiana Department of Environmental Quality (“DEQ”) for
         the period of 2011 through 2015, showing concentrations well
         above the 0.2 µg/m³ threshold. At a meeting on December 8,
         2016, DEQ Secretary Chuck Brown dismissed those
         expressing concern about the chloroprene concentrations as
         “fearmongerers” and said “forget about 0.2[µg/m³].”
                The EPA’s National Enforcement Investigation Center
         (“NEIC”) conducted a Clean Air Act (“CAA”) inspection of
         the Pontchartrain Works facility in June 2016. A copy of the
         redacted inspection report from the EPA’s CAA inspection
         was publicized on April 3, 2017. The NEIC inspection report
         revealed various areas of non-compliance by both DuPont and
         Denka in their operation of the facility, including failure to
         adhere to monitoring, recordkeeping, and reporting
         requirements for the chloroprene vent condenser; failure to
         replace leaking valves; failure to include appropriate emissions
         factors in air permit application materials; and failure to

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           institute appropriate emissions controls for the chloroprene
           Group I storage tank.
   Butler II, 2019 WL 1160814, at *1–2.
           Butler herself is a resident of LaPlace, Louisiana, in St. John the
   Baptist Parish. Since 1998, she has resided and worked within 5.5 miles of
   the PWF. Butler alleges that DuPont and Denka have emitted, and continue
   to emit, chloroprene at levels resulting in concentrations exceeding the upper
   limit of acceptable risk. Specifically, she alleged in paragraph 24 of her initial
   complaint:
                   Due to the Plaintiff’s exposure to the chloroprene
           emissions, she has experienced symptoms attributable to
           exposure of said chemical. Since April 2012 until current date,
           the Plaintiff has continually sought medical attention for the
           following conditions: acute bronchitis; coughing; throat
           irritation; redness and swelling; nasal blockage, congestion,
           and sneezing; sinusitis and nasal polyps; exacerbation of pre-
           existing asthma; shortness of breath; wheezing; rhinosinusitis;
           thyroid enlargement; cardiac problems; nausea; vomiting;
           headaches; fatigue; epistaxis (nose bleeds); anxiety;
           depression; insomnia; and temporary hair loss. 7
           Butler also seeks to represent a putative class on behalf of:
                  (1) Those persons who, at any time from January 1, 2011
           through the present, have lived, worked, attended school,

           7
             Both the district and magistrate judges below discerningly highlight that Butler
   omitted these specific allegations in her second amended petition (“SAP”) in lieu of more
   generalized descriptions of her symptoms. As a result, Butler’s SAP alleges only that she
   “has experienced the symptoms and/or medical conditions and/or illnesses; and exposure
   referenced in the said class definition,” without referring to a specific onset date. The
   magistrate judge nonetheless considered the omitted allegations in Butler’s initial “verified
   complaint,” including Butler’s alleged onset date of April 2012, as “an affidavit.” Absent
   any argument to the contrary, we do the same here.

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           and/or actually resided within a geographical boundary of St.
           John the Baptist Parish . . .; and
                   (2) who experienced one or more of the following
           physical symptoms: headaches; sinus problems; dizziness;
           insomnia; trouble breathing; respiratory irritation, or other
           respiratory problems; chest pains; acute cardiac palpitations;
           acute gastrointestinal disorder; acute bronchitis; acute onset of
           asthma; exacerbation of pre- existing asthma; fatigue; nausea;
           skin rash; temporary hair loss; chronic coughing; chronic nasal
           discharge; chronic cardiovascular disorder; chronic throat
           irritation; chronic eye irritation; chronic thyroid disorder;
           anxiety; and depression, resulting from their exposure to
           chloroprene or other chemical substance released from the
           Pontchartrain Works Facility. 8
           Butler asserts various state tort claims against each of the defendants,
   and seeks class certification, damages, declaratory relief, and injunctive relief
   including an abatement of chloroprene releases from the PWF.
           The district court ultimately dismissed Butler’s claims against
   DuPont and DOH as prescribed by Louisiana’s one-year limitations period,
   reversed in part the magistrate judge’s order granting leave to add strict
   liability claims against DuPont and dismissed those claims as futile, and
   dismissed the remaining continuing tort claims against Denka for failure to
   state a plausible claim. Judgment was entered in favor of the defendants on
   June 4, 2020, and this appeal timely followed. 9

           8
             The putative class definition remained substantively identical in the SAP, except
   that Butler revised the last sentence to specify that the exposure includes “chloroprene
   (chlorobutadiene, C4H5Cl) and/or chloroprene-containing substances emitted, released, or/or
   leaked from the PWF.” This amendment is immaterial to our analysis.
           9
            We note that, independent of the issues presented in this appeal, there are similar
   cases pending in state and federal court asserting claims relating to the PWF’s chloroprene

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                                                II.
           Butler first challenges the district court’s denial of her motion to
   remand the case to state court, which we review de novo. Waste Mgmt., Inc. v.
   AIG Specialty Ins. Co., 974 F.3d 528, 532 (5th Cir. 2020).
           Denka and DuPont timely removed the case to federal court under the
   Class Action Fairness Act, 28 U.S.C. § 1332(d), and the district court
   concluded that minimal diversity existed between Butler, a Louisiana citizen,
   and DuPont, a Delaware citizen based on its state of incorporation and the
   location of its corporate headquarters. On appeal, Butler argues that the
   district court lacked subject matter jurisdiction and that the state agency
   defendants are immune from suit in federal court. She primarily asserts that
   at the time of removal, DOH and DEQ had not waived immunity, and
   alternatively that their post-removal waiver was not authorized by the state
   legislature.
           While Butler’s primary challenge is based on sovereign immunity, her
   premise that she could not file this suit in federal court in the first instance
   misunderstands CAFA. CAFA significantly expanded federal diversity
   jurisdiction over interstate class action claims. 10              Contrary to Butler’s

   emissions. We express no opinion as to the merits of those claims, and address only
   Butler’s asserted claims here. See, e.g., Order and Reasons, Gerard v. Denka Performance
   Elastomer LLC, No. 18-cv-5739 (E.D. La. Oct. 15, 2018), ECF No. 8 (granting motion to
   remand to state court); Scheduling Order, Taylor v. Denka Performance Elastomer LLC, No.
   17-cv-7668 (E.D. La. Apr. 6, 2020), ECF No. 126 (setting bench trial on nuisance claims
   for April 4, 2022); Order, Acosta v. Denka Performance Elastomer, LLC, No. 21-30136 (5th
   Cir. June 10, 2021), ECF No. 51 (staying proceedings in related appeal).
           10
             See Class Action Fairness Act of 2005, Pub. L. No. 109-2, § 2, 119 Stat. 4 (2005)
   (“The purposes of this Act are to . . . restore the intent of the framers of the United States
   Constitution by providing for Federal court consideration of interstate cases of national
   importance under diversity jurisdiction.”); id. §§ 4-5 (amending federal court subject
   matter and removal jurisdiction as codified in 28 U.S.C. §§ 1332, 1453).

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   assertions, CAFA expanded district courts’ “original jurisdiction” to
   include “any civil action in which the matter in controversy exceeds the sum
   or value of $5,000,000, . . . and is a class action in which[] any member of a
   class of plaintiffs is a citizen of a State different from any defendant.” 28
   U.S.C. § 1332(d)(2)(A).
          As the district court concluded, CAFA’s “minimal diversity”
   requirement is satisfied because Butler is a resident and citizen of Louisiana,
   and DuPont is a citizen of Delaware. See In re Katrina Canal Litig. Breaches,
   524 F.3d 700, 705 (5th Cir. 2008); 28 U.S.C. § 1332(d)(2)(A). It is true that
   even under CAFA, “a state is not a citizen” for diversity purposes. In re
   Katrina Canal Litig., 524 F.3d at 706. However, a state’s presence does not
   affect CAFA’s minimal—rather than complete—diversity requirement. See
   id.
          Butler next contends that removal was improper because the state
   defendants had not waived their sovereign immunity at the time of removal.
   Not so. CAFA permits removal by “any defendant without the consent of all
   defendants.”     28 U.S.C. § 1453(b) (emphasis added); cf. 28 U.S.C.
   § 1446(b)(2)(A) (requiring that “all defendants who have been properly
   joined and served must join in or consent to the removal of the action” under
   § 1441(a)). This rule allows defendants to remove a case to federal court
   without first obtaining consent—and therefore waiver of sovereign
   immunity—from any joined state defendants, which is what occurred here.
   While it is true that under CAFA, “a state may find itself in a case removed
   to federal court without having joined in the removal,” this procedure does
   not itself infringe the state’s sovereign immunity because the “state, having
   taken no affirmative act, has not waived immunity and can still assert it.”
   Frazier v. Pioneer Ams. LLC, 455 F.3d 542, 547 (5th Cir. 2006) (citing Lapides
   v. Bd. of Regents of Univ. Sys. of Ga., 535 U.S. 613, 616 (2002)). Consequently,
   “CAFA, like other statutes, provides jurisdiction over cases in which states

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   may, if they choose, be defendants, thus respecting state dignity interests.”
   Id.; accord In re Katrina Canal Litig., 524 F.3d at 706 (holding that CAFA’s
   expanded jurisdiction “does not tax the [state’s] immunity,” even when the
   state was involuntarily removed to federal court).
          Butler further argues that removal was barred by the Eleventh
   Amendment, which grants states (and qualifying state agencies) immunity
   from suits brought by citizens in federal court. Lapides, 535 U.S. at 616 (citing
   Hans v. Louisiana, 134 U.S. 1 (1890)). However, it is well established that
   states can waive this immunity. Id. at 618 (“A State remains free to waive its
   Eleventh Amendment immunity from suit in a federal court.”). A state’s
   voluntary appearance in federal court, including through removal,
   constitutes such waiver. Id. at 619–20. Such a waiver is precisely what
   occurred here: DEQ and DOH—both represented by the state’s attorney
   general—expressly waived their Eleventh Amendment immunity in
   opposing Butler’s motion to remand.
          Notwithstanding this express consent, Butler argues that Louisiana
   has categorically rejected any waiver of its sovereign immunity, and that
   neither the DEQ, DOH, nor the attorney general has authority to waive
   sovereign immunity or consent to federal court jurisdiction. Butler relies on
   Louisiana Revised Statutes section 13:5106(A), which states: “No suit
   against the state or a state agency or political subdivision shall be instituted
   in any court other than a Louisiana state court.”
          Butler’s arguments are unavailing. To start, we have previously
   interpreted section 13:5106(A) narrowly as recognizing Louisiana’s waiver of
   “its immunity in state, but not federal, court.” Frazier, 455 F.3d at 547.
          Moreover, the Supreme Court rejected a nearly identical argument by
   the State of Georgia in Lapides v. Board of Regents of the University System of
   Georgia. In that case, Georgia’s attorney general consented to removal of a

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   professor’s lawsuit for state and federal claims against the Georgia state
   university system and university officials. Lapides, 535 U.S. at 616, 622.
   Following removal, Georgia sought to invoke its sovereign immunity to
   dismiss the claims. Id. at 616–17. The Supreme Court held that Georgia’s
   voluntary invocation of federal jurisdiction by consenting to removal
   constituted waiver. Id. at 620–24. In doing so, the Court rejected Georgia’s
   argument that the attorney general did not have statutory authority to “waive
   the State’s Eleventh Amendment immunity. . . even after it removed its case
   to federal court[.]” Id. at 621–22. The Court emphasized that “[a] rule of
   federal law that finds waiver through a state attorney general’s invocation of
   federal-court jurisdiction avoids inconsistency and unfairness,” as opposed
   to a rule that “denies waiver despite the state attorney general’s state-
   authorized litigating decision.” Id. at 623. 11 Lapides likewise controls here. 12
           Accordingly, we agree with the district court that removal was proper
   pursuant to CAFA, and the state agencies have consented to federal
   jurisdiction thereby waiving any sovereign immunity in this case.

           11
              Lapides acknowledged that it did not consider whether its holding would apply to
   federal claims against a state defendant, or where the state has not waived its underlying
   sovereign immunity from suit in state courts. Lapides, 535 U.S. at 617–18; accord Meyers ex
   rel. Benzing v. Texas, 410 F.3d 236, 247 (5th Cir. 2005) (extending Lapides’s “voluntary
   invocation principle and its waiver-by-removal rule” as “fully applicable to suits based on
   federal-law claims”). This is of no concern here because this case is squarely controlled by
   Lapides: Butler alleges only state tort claims, and no party argues that Louisiana prohibits
   such claims against state defendants in state court. To the contrary, Butler asserts the
   opposite in arguing for remand.
           12
             Butler does not contest that the Louisiana attorney general is authorized to
   represent DEQ and DOH in this litigation. See Meyers, 410 F.3d at 247 (“[A] rule of federal
   law that finds waiver through invocation of federal court jurisdiction by an attorney
   authorized to represent the state in the pertinent litigation would avoid inconsistency and
   unfairness.” (emphasis added) (citing Lapides, 535 U.S. at 622–24)); see also La. R.S.
   49:257(A) (“[T]he attorney general shall represent the state and all departments and
   agencies of state government in all litigation arising out of or involving tort. . . .”).

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                                        III.
          Satisfied of our jurisdiction, we turn to the merits. We review the
   district court’s dismissal for failure to state a claim de novo, “applying the
   same standard applied by the district court.” Masel v. Villarreal, 924 F.3d
   734, 742–43 (5th Cir. 2019), as revised (June 6, 2019). A denial of a motion to
   amend the complaint is reviewed for abuse of discretion, but when the denial
   is based on the futility of amendment for failure to state a claim upon which
   relief could be granted, as here, we review that denial de novo under the same
   standards as a dismissal under Rule 12(b)(6). Villarreal v. Wells Fargo Bank,
   N.A., 814 F.3d 763, 766 (5th Cir. 2016).
                                         A.
          Butler first challenges the dismissal of her claims against DuPont and
   DOH as time-barred. Butler alleges that DuPont, as the former neoprene
   manufacturer until 2015 and current owner of the PWF’s land and buildings,
   is liable for various tort claims arising from the chloroprene emissions. She
   also claims that DOH failed to adequately warn Butler and the community
   about the dangers of chloroprene exposure and failed to fully investigate the
   health effects of chloroprene. We first consider whether Butler’s allegations
   on their face are prescribed, and second, whether any tolling of prescription
   applies.
                                         1.
          Under Louisiana’s civil code, Butler’s alleged tort claims are “subject
   to a liberative prescription of one year,” which “commences to run from the
   day injury or damage is sustained.” La. Civ. Code art. 3492. “When
   damages are not immediate, the action in damages is formed and begins to
   prescribe only when the tortious act actually produces damage and not on the
   day the act was committed.” Tenorio v. Exxon Mobil Corp., 170 So. 3d 269,
   274 (La. Ct. App. 2015). An injury or damage is sustained “when it has

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   manifested itself with sufficient certainty to support accrual of a cause of
   action.” Id. “‘The burden of proof is normally on the party pleading
   prescription; however, if on the face of the petition it appears that
   prescription has run, . . . the burden shifts to the plaintiff to prove a
   suspension or interruption of the prescriptive period’ based on the equitable
   doctrine of contra non valentem.” In re Taxotere (Docetaxel) Prods. Liab. Litig.,
   995 F.3d 384, 388–89 (5th Cir. 2021) (quoting Younger v. Marshall Indus. Inc.,
   618 So. 2d 866, 869 (La. 1993)); accord Hogg v. Chevron USA, Inc., 45 So. 3d
   991, 998 (La. 2010).
           Butler filed her initial complaint in state court on June 5, 2018.
   Therefore, for Butler’s claims to be timely, the prescription period must have
   begun or been tolled until June 5, 2017. Butler alleged that she began seeking
   treatment for symptoms of chloroprene exposure in April 2012, which is the
   date her injury first accrued. Thus, unless tolled, the one-year prescription
   expired well before Butler filed suit six years later.
                                               2.
           We next consider whether Butler has met her burden in proving that
   prescription was tolled under the doctrine of contra non valentem. In re
   Taxotere, 995 F.3d at 388–89. At the pleadings stage, she has.
           Contra non valentem 13 is an equitable doctrine that tolls prescription
   where, inter alia, “the cause of action is neither known nor reasonably
   knowable by the plaintiff.” Marin v. Exxon Mobil Corp., 48 So. 3d 234, 245
   (La. 2010). Under this doctrine, “the prescriptive period begins to run ‘on
   the date the injured party discovers or should have discovered the facts upon

           13
             From the Latin expression contra non valentem agere nulla currit praescriptio
   (“Prescription does not run against a party unable to act”). Crier v. Whitecloud, 496 So. 2d
   305, 307 & n.4 (La. 1986).

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   which his cause of action is based.’” Chevron USA, Inc. v. Aker Mar., Inc.,
   604 F.3d 888, 893 (5th Cir. 2010) (quoting Griffin v. Kinberger, 507 So. 2d
   821, 823 (La. 1987)). The exact time at which prescription begins to run
   “depends on the reasonableness of a plaintiff’s action or inaction.” Knaps v.
   B & B Chem. Co., 828 F.2d 1138, 1140 (5th Cir. 1987) (per curiam) (quoting
   Jordan v. Emp. Transfer Corp., 509 So. 2d 420, 423 (La. 1987)).
             Consequently, prescription begins only “when a plaintiff obtains
   actual or constructive knowledge of facts indicating to a reasonable person
   that he or she is the victim of a tort.” Campo v. Correa, 828 So. 2d 502, 510
   (La. 2002). “Constructive knowledge is whatever notice is enough to excite
   attention and put the injured party on guard and call for inquiry. Such notice
   is tantamount to knowledge or notice of everything to which a reasonable
   inquiry may lead.” Id. at 510–11. “That means prescription runs ‘from the
   time there is notice enough to call for inquiry about a claim, not from the time
   when the inquiry reveals facts or evidence sufficient to prove the claim.’” In
   re Taxotere, 995 F.3d at 391 (quoting Terrel v. Perkins, 704 So. 2d 35, 39 (La.
   Ct. App. 1997)). Under this standard, “a plaintiff will be deemed to know
   what he could have learned with reasonable diligence.” Tenorio, 170 So. 3d
   at 274.
             Butler first contends contra non valentem applies because she was not
   “aware in April 2012 that her symptoms were caused by chloroprene, much
   less that acts of [DuPont] and DOH were causing her symptoms.” But actual
   knowledge is not required.
             Butler next contends that she lacked even constructive knowledge that
   the chloroprene emissions from PWF caused her symptoms.                 “[T]he
   ultimate issue in determining whether [Butler] had constructive knowledge
   sufficient to commence a prescriptive period is the reasonableness of
   [Butler’s] action or inaction in light of [her] education, intelligence, and the

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   nature of the defendant’s conduct.” Wells v. Zadeck, 89 So. 3d 1145, 1151 (La.
   2012) (quoting Marin, 48 So. 3d at 246). Consequently, “the reasonableness
   of the plaintiff’s actions centers upon the knowledge she possessed.” Id. at
   1152. 14 Louisiana courts consistently consider “the reasonableness of a
   plaintiff’s action or inaction” based on the position she is in—including the
   information known or otherwise available to her at the time. See Jordan, 509
   So. 2d at 423; see also Knaps, 828 F.2d at 1140; Lennie v. Exxon Mobil Corp.,
   251 So. 3d 637, 646 (La. Ct. App. 2018).
           Butler’s specific allegations as to the onset of her symptoms
   attributable to chloroprene and her ensuing treatment are admittedly thin. 15
   However, at the pleadings stage, Butler need only allege “sufficient factual
   matter, accepted as true, to ‘state a claim to relief that is plausible on its
   face.’” Ashcroft v. Iqbal, 556 U.S. 662, 678 (2009) (quoting Bell Atl. Corp. v.
   Twombly, 550 U.S. 544, 570 (2007)). Here, consistent with the pleadings
   standard in which we must “accept all well-pleaded facts as true and view all
   facts in the light most favorable to the plaintiff,” Thompson v. City of Waco,
   764 F.3d 500, 502 (5th Cir. 2014), she has alleged enough.
           While Butler’s FAP alleged that she began experiencing symptoms in
   April 2012 that were ultimately linked to chloroprene exposure—i.e. “[d]ue
   to Plaintiff’s exposure to the chloroprene emissions”—more facts are
   necessary to determine when she received notice of such linkage. Contrary to
   defendants’ urging, we decline to read the complaint’s phrasing of “due to”

           14
               This reasonableness standard does not require Butler to have known in April
   2012 that her symptoms were attributable to chloroprene emissions from the PWF, which
   would be more akin to an actual knowledge standard. See, e.g., Luckett v. Delta Airlines,
   Inc., 171 F.3d 295, 300 (5th Cir. 1999) (“To decide otherwise would be to say that a plaintiff
   must know the cause of her damage, taking away the constructive knowledge component of
   the rule.”).
           15
                See supra n.7

                                                14
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                                          No. 20-30365

   so narrowly to mean that Butler knew, in 2012, that chloroprene caused her
   symptoms. Indeed, at oral argument, Butler’s counsel clarified that Butler’s
   symptoms “were not linked to chloroprene until much, much later.” 16
           DuPont rightfully concedes that its stronger argument is that Butler—
   at some point after she first started seeking medical treatment—was on
   constructive notice that chloroprene may have been responsible for her
   symptoms. But that fact-bound conclusion is not evident to us at the
   pleadings stage. 17      While conclusive proof as to the cause of Butler’s
   symptoms is not required to satisfy constructive notice that begins the
   prescriptive period, there must be “enough notice to call for an inquiry about
   a claim.” Luckett v. Delta Airlines, Inc., 171 F.3d 295, 300 (5th Cir. 1999)
   (“The commencement of prescription does not necessarily wait for the
   pronouncement of a victim’s physician or of an expert. . . . [T]he prescriptive
   period commences when there is enough notice to call for an inquiry about a
   claim, not when an inquiry reveals the facts or evidence that specifically
   outline the claim.” (internal citations omitted)). On the record before us, we

           16
              We understand why the district and magistrate judges reached the opposite
   conclusion based on the imprecise pleading in Butler’s FAP and SAP implying that Butler
   was aware, as of April 2012, that her symptoms was attributable to chloroprene exposure.
   Indeed, this may be determinative following discovery, where both parties will have the
   opportunity to develop the facts relating to Butler’s medical treatment history. Similarly,
   the parties can probe, as the district court postulated, whether “[s]eeking medical attention
   for approximately 20 symptoms consistently for years would put a reasonable person on
   guard to inquire into why she is suffering persistently with so many symptoms.” Butler II,
   2019 WL 1160814, at *4.
           17
              Indeed, the Louisiana cases primarily relied on by the parties were decided only
   after an evidentiary hearing on prescription. See, e.g., Wells, 89 So. 3d at 1147–48; Tenorio,
   170 So. 3d at 274; Lennie, 251 So. 3d at 644–46; Guerin v. Travelers Indemnity Co., 296 So.
   3d 625, 628 (La. Ct. App. 2020). Likewise, the federal cases we find instructive were
   similarly decided on motions for summary judgment. See, e.g., In re Taxotere, 995 F.3d at
   388; Luckett, 171 F.3d at 300; Jenkins v. Bristol-Myers Squibb Co., 689 F. App’x 793, 795
   (5th Cir. 2017); Crochet v. Bristol-Myers Squibb Co., 804 F. App’x 249, 250 (5th Cir. 2020).

                                                15
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                                          No. 20-30365

   cannot say at what point Butler received such notice. Indeed, that may be
   dispositive upon further discovery of Butler’s medical treatment history as
   to what she learned, and when she learned it. Compare, e.g., Jenkins v. Bristol-
   Myers Squibb Co., 689 F. App’x 793, 796–97 (5th Cir. 2017), with Crochet v.
   Bristol-Myers Squibb Co., 804 F. App’x 249, 252–55 (5th Cir. 2020).
           Moreover, DuPont and DOH primarily rely on cases in which a
   plaintiff’s diagnosis, more than one year prior to filing suit, constitutes
   constructive notice. But that distinction is critical, and supports our contrary
   holding here. Significantly, as alleged in her pleadings, Butler was not
   diagnosed or otherwise told that her symptoms were a result of excessive
   chloroprene emissions more than one year prior to filing suit. Cf. Tenorio,
   170 So. 3d at 275 (“[Plaintiff’s] diagnosis was constructive notice sufficient
   to put [him] on guard and to call him to inquire into the cause of his
   condition.” (emphasis added)); Lennie, 251 So. 3d at 648 (“Mr. Lennie’s
   diagnosis of lung cancer in January 2010 was constructive notice sufficient to
   put the [plaintiffs] on guard and to call for them to inquire further into the
   cause of his condition.” (emphasis added)); Guerin v. Travelers Indem. Co.,
   296 So. 3d 625, 631 (La. Ct. App. 2020) (“[Plaintiff’s] diagnosis in 2015 was
   constructive notice sufficient to put him on guard and to call him to inquire
   into the cause of his condition.” (emphasis added)). 18

           18
              Again, defendants DuPont and DOH’s reliance on these cases for the
   proposition “that medical diagnosis triggers the duty to inquire” is inapt, as Butler does
   not allege that she was ever diagnosed. Indeed, even years of seeking and receiving medical
   treatment leading up to a diagnosis does not necessarily trigger the running of prescription.
   See Zumo v. R.T. Vanderbilt Co., 527 So. 2d 1074, 1077–78 (La. Ct. App. 1988) (holding, on
   summary judgment, that prescription did not begin to run on plaintiff’s claim that exposure
   to workplace chemicals caused his skin cancer until his cancer diagnosis, even though he
   had been diagnosed with chronic dermatitis and first learned he was allergic to those
   chemicals four years earlier).

                                                16
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                                         No. 20-30365

           At oral argument, DuPont attempted to distinguish these cases by
   asserting that “latent” “cellular level diseases like cancer” require a
   diagnosis before prescription runs, but that Butler’s symptoms were
   “severe” “overt injuries” sufficient to constitute constructive notice
   without a diagnosis. We choose not to reach such an intensely fact-based
   distinction at the pleadings stage and on the sparse record before us. This
   further demonstrates why discovery—at least as to prescription—is
   warranted here.
           Finally, our conclusion is further bolstered by defendants’ consistent
   denial that chloroprene—either in April 2012 or in the years since—caused
   any of Butler’s symptoms. In other words, absent a diagnosis or any facts
   that Butler received sufficient notice linking her symptoms to chloroprene,
   and drawing all reasonable inferences in Butler’s favor at the pleadings stage,
   we cannot conclude that Butler had constructive notice more than one year
   prior to filing suit. Consistent with Louisiana’s contra non valentem analysis
   as to what Butler reasonably knew or should have known at the time, we
   disagree that, on the record before us, Butler had constructive knowledge
   sufficient to trigger the running of prescription over a year before she filed
   suit in June 2018. See Wells, 89 So. 3d at 1151. Accordingly, we reverse the
   district court’s holding that Butler’s claims were prescribed. 19
                                               B.
           Second, Butler appeals the denial of her motion to amend her
   complaint to assert a claim against DuPont for the ongoing chloroprene

           19
              DOH alternatively argues that Butler’s claims against it are prescribed based on
   its July 2016 community meeting and subsequent actions. However, the reasonableness of
   whether Butler could or should have discovered, or attended, these community meetings
   is likewise dependent on undeveloped facts, especially the circumstances of her medical
   treatment.

                                               17
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                                     No. 20-30365

   emissions. Specifically, Butler claimed that DuPont and Denka were strictly
   liable for the PWF’s ongoing chloroprene emissions from PWF’s
   “defective” neoprene production units pursuant to Louisiana Civil Code
   Articles 2317 and 2317.1. Butler alleged that DuPont “owned and operated
   the entire PWF from 1969 to 2015,” when it sold the PWF to Denka. After
   the sale, “except for the neoprene manufacturing units of the PWF . . . DuPont
   retained ownership of the entirety of the PWF land and buildings, including
   the building where it currently manufactures Kevlar.” Thus, Butler asserts,
   DuPont and Denka are both liable because “during separate periods of time,
   [they] have had ownership, care, custody, and control of the neoprene units
   of the PWF; and DuPont has maintained care, custody, and control of the
   PWF since 1969.”
          The first requirement for strict (custodial) liability is that “[t]he thing
   which caused injury must be in the care, custody and control of the
   defendant.” Palermo v. Port of New Orleans, 951 So. 2d 425, 438 (La. App.
   2007) (emphasis added); accord Fruge ex rel. Fruge v. Parker Drilling Co., 337
   F.3d 558, 565 (5th Cir. 2003). “Louisiana courts have generally held that (1)
   ownership of a thing establishes a rebuttable presumption of custody or
   ‘garde,’ and (2) in a case of non-ownership, a defendant may be found to have
   custody over property when he exercises direction and control of the thing
   and derives some benefit from it.” Coulter v. Texaco, Inc., 117 F.3d 909, 913
   (5th Cir. 1997); accord Davis v. Riverside Court Condo. Ass’n Phase II, Inc., 154
   So. 3d 643, 648 (La. App. 2014) (“[I]n determining whether a thing is in
   one’s custody or garde, courts should consider (1) whether the person bears
   such a relationship as to have the right of direction and control over the thing;
   and (2) what, if any, kind of benefit the person derives from the thing.”

                                          18
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                                         No. 20-30365

   (alteration in original) (quoting Dupree v. City of New Orleans, 765 So. 2d
   1002, 1009 (La. 2000))). 20
           We agree with the district court that the “thing” Butler must show
   “custody” of to succeed on her custodial liability claim is the PWF’s
   “neoprene production units,” rather than the land itself. Under Articles
   2317 and 2317.1, the defective “object” is distinct from the property on which
   the injury occurred, unless an inherent defect in the property caused the
   injury. Compare Doughty v. Insured Lloyds Ins. Co., 576 So. 2d 461, 464 (La.
   1991) (defective machinery located on the property was considered “the
   object,” not the property itself), with Dupree, 765 So. 2d at 1005 (property
   was considered “the object” where cause of the injury was the property itself:
   a cave-in on a New Orleans city street). Butler does not argue that the PWF
   as a whole or the underlying land caused the “defect,” but rather that “both
   DuPont and Denka have garde over the neoprene units and other sources of
   chloroprene emissions at DuPont’s PWF.”
           The district court next concluded that Butler failed to allege garde over
   the neoprene production units after 2015 because “mere ownership” of the
   land and buildings is “insufficient to state a plausible strict or custodial
   liability claim against DuPont when [Butler’s] own allegations state that,
   since 2015, Denka alone had custody over and operated the objects allegedly
   causing the harm, the allegedly faulty neoprene units operated during the
   manufacturing process.” Butler III, 2019 WL 2417500, at *5.
           Generally, “[d]etermining who has the custody or garde of the thing
   is a fact driven determination.” Dupree, 765 So. 2d at 1009. Here, Butler

           20
             Neither Butler nor DuPont addresses, or appears to contest, whether DuPont
   “derives some benefit” from Denka’s ownership and operation of the PWF’s neoprene
   production units. Rather, they focus only on whether DuPont has or can exercise sufficient
   “custody” or “control.”

                                              19
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                                    No. 20-30365

   principally argues that because DuPont retained ownership of the land and
   buildings, it likely retained some contractual control over Denka’s neoprene
   production as well. For example, Butler’s counsel asserted at oral argument
   that “it would seem a logical inference that DuPont still has some rights over
   what Denka is doing on DuPont’s property.” DuPont, in response, argues
   that Butler fails to allege any facts to support that, aside from ownership of
   the land, DuPont retains control or custody over PWF’s neoprene
   production units.
          We need not resolve whether Butler alleges enough, here, to support
   her contention that DuPont has garde over PWF’s neoprene production
   units. For the reasons that follow, Butler’s custodial liability claims against
   DuPont fail for the same reason as her claims against Denka: a failure to state
   a plausible duty and corresponding breach. See Socorro v. City of New Orleans,
   579 So. 2d 931, 937 (La. 1991) (finding no liability even though the defendant
   had garde over the injury-causing defect).
                                         C.
          Next, Butler appeals the dismissal of her negligence and strict
   custodial liability claims against Denka arising from its past and current
   neoprene manufacturing at the PWF. Butler says that Denka “has failed to
   exercise reasonable care to prevent [the] emission of unreasonably dangerous
   chloroprene concentrations into the air,” and that “Denka’s neoprene
   manufacturing equipment is unreasonably dangerous, because of its
   excessive chloroprene emissions.” Though not prescribed because of the

                                         20
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                                          No. 20-30365

   continuing tort doctrine, the district court granted Denka’s motion to dismiss
   for failure to state a plausible claim. 21 We agree.
                                                1.
           As to the negligence claims, Butler asserts that Denka unreasonably
   emits dangerous chloroprene concentrations in violation of Louisiana Civil
   Code Articles 2315 and 2316. Those articles provide that “[e]very act
   whatever of man that causes damages to another obliges him by whose fault
   it happened to repair it,” La. Civ. Code art. 2315(A), and that “[e]very
   person is responsible for the damage he occasions not merely by his act, but
   by his negligence, his imprudence, or his want of skill,” La. Civ. Code art.
   2316. Under Louisiana law’s duty-risk analysis of negligence liability, Butler
   must prove five separate elements: “(1) the defendant had a duty to conform
   his conduct to a specific standard (the duty element); (2) the defendant’s
   conduct failed to conform to the appropriate standard (the breach element);
   (3) the defendant’s substandard conduct was a cause in fact of the plaintiff’s
   injuries (the cause-in-fact element); (4) the defendant’s substandard conduct
   was a legal cause of the plaintiff’s injuries (the scope of liability or scope of
   protection element); and (5) the actual damages (the damages element).”
   Lemann v. Essen Lane Daiquiris, 923 So. 2d 627, 633 (La. 2006). Duty is the
   “threshold issue.” Id.
           As to strict custodial liability, Butler argues that Denka is the owner
   or custodian of a defective thing—the neoprene manufacturing equipment—

           21
               The district court dismissed Butler’s claims against Denka in her FAP for failure
   to state in a claim on March 13, 2019, Butler II, 2019 WL 1160814, at *7, and then dismissed
   Butler’s amended claims in her SAP for largely similar reasons on May 27, 2020, Butler IV,
   2020 WL 2747276, at *1. Because the dismissal orders largely overlap, we draw primarily
   from the final dismissal order. Like the district court, despite Butler’s inexcusable neglect
   in filing her second amended petition ten days late, we address the merits of Denka’s
   motion to dismiss.

                                                21
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                                      No. 20-30365

   in violation of Louisiana Civil Code Articles 2317 and 2317.1. Those articles
   provide that “[w]e are responsible, not only for the damage occasioned by
   our own act, but for that which is caused by . . . the things which we have in
   our custody,” La. Civ. Code art. 2317,               and that “[t]he owner or
   custodian of a thing is answerable for damage occasioned by its ruin, vice, or
   defect, only upon a showing that he knew or, in the exercise of reasonable
   care, should have known of the ruin, vice, or defect which caused the damage,
   that the damage could have been prevented by the exercise of reasonable
   care, and that he failed to exercise such reasonable care,” La. Civ. Code
   art. 2317.1; accord Renwick v. PNK Lake Charles, L.L.C., 901 F.3d 605, 616
   (5th Cir. 2018) (citing Bufkin v. Felipe’s La., LLC, 171 So. 3d 851, 855 (La.
   2014)).
          “Strict liability” is a misnomer, however, because Article 2317.1’s
   knowledge requirement “effectively eliminated strict liability . . . turning it
   into a negligence claim.” Renwick, 901 F.3d at 617 n.12 (quoting Burmaster v.
   Plaquemines Parish Gov’t, 982 So.2d 795, 799 n.1 (La. 2008)). Accordingly, a
   claim for “strict” liability requires that a duty of care was breached, just as a
   negligence claim does. Bd. of Comm’rs v. Tenn. Gas Pipeline Co., 850 F.3d
   714, 729 n.52 (5th Cir. 2017) (citing Oster v. Dep’t of Transp. & Dev., 582
   So. 2d 1285, 1288 (La. 1991)). “There is essentially no difference between
   the two types of claims under Louisiana law . . . .” Id. at 729.
                                           2.
          Here, Butler fails to adequately allege a duty owed by Denka, and
   consequently whether Denka breached such a duty.                 Thus, both the
   negligence and strict liability claims fail to state a plausible claim.
          Butler repeatedly references the EPA’s NATA recommended
   “acceptable risk” chloroprene emissions threshold of 0.2 µg/m³
   (micrograms per cubic meter).          The district court dismissed Butler’s

                                           22
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                                         No. 20-30365

   invocation of that threshold as a legal duty because it is “less than a federal
   regulation” and even the EPA “disclaims” it as an “absolute risk measure”
   of toxicity. Butler IV, 2020 WL 2747276, at *10–11. The district court
   concluded that Butler “fails to allege that [Denka] had a duty to conform its
   conduct to a specific legally-enforceable standard (or any corresponding duty
   to warn the plaintiff concerning its business operations) and that it breached
   that duty.” Id. at *9. Thus, the court concluded that Butler’s “allegations
   concerning [Denka’s] duty and breach are conclusory and speculative”
   because her “theory that [Denka] owed a duty not to exceed a certain level
   of emissions and breached that duty is not plausible.” Id. at *12. 22
           On appeal, Butler now disclaims any reliance on the EPA’s stated risk
   threshold.      Although Butler sought to enjoin Denka from emitting
   chloroprene “in excess of 0.2 micrograms (mcg) per cubic meter into the
   air,” she now contends that the district court “misconstrued” her
   petitions. 23 Instead, Butler asserts that Denka violated Louisiana’s general
   duty “to use reasonable care to avoid injury to another.” Rando v. Anco
   Insulations, Inc. 16 So. 3d 1065, 1086 (La. 2009).                  She says Denka’s

           22
             The district court further noted that Butler’s allegations were belied by another
   source incorporated by reference in her SAP: the OSHA “Hazardous Substances Data
   Bank” report, which includes a permissible exposure limit of “25 parts per million, or 90
   milligrams per cubic meter, which is the equivalent of 90,000 micrograms per cubic
   meter.” Id. at *12. The court emphasized that the OSHA report’s conflicting
   “acceptable” exposure limit “detracts from [Butler’s] attempt to plausibly suggest that .2
   micrograms per cubic meter represents a ‘safe’ exposure threshold.” Id.
           23
              For example, Butler’s FAP initially sought to enjoin Denka from emissions of
   chloroprene “in excess of 0.2 micrograms (mcg) per cubic meter into the air.” Her SAP
   likewise relies on NATA’s 0.2 micrograms threshold, and seeks to enjoin Denka from
   emitting “chloroprene into the air from the PWF at levels in excess of 0.2 micrograms
   (mcg) per cubic meter or at levels in excess of what this Court otherwise finds to be safe.”

                                               23
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                                            No. 20-30365

   chloroprene       emissions—untethered              from     any    particular      emissions
   threshold—are nonetheless unreasonably excessive.
           While we remain skeptical of Butler’s contention that the district
   court misconstrued her claims, 24 Butler’s retreat to generalized grievances is
   unavailing.      While Louisiana law does impose a “universal duty” on
   defendants in a negligence action to use “reasonable care,” Rando, 16 So. 3d
   at 1086, plaintiffs are still required to assert a “specific standard” of care. See
   Lemann, 923 So. 2d at 633. 25 The inquiry into a defendant’s particular duty

           24
              For example, in her opening brief on appeal, Butler asserts that although Denka
   is “familiar with the NATA findings” which “established a chloroprene concentration
   acceptable risk threshold of not more than .2 micrograms per cubic meter of air,” the
   chloroprene emissions at PWF “are hundreds of times that acceptable risk threshold.”
   Moreover, Butler’s attempt to change course on appeal is not well taken. In general, we do
   “not allow a party to raise an issue for the first time on appeal merely because a party
   believes that he might prevail if given the opportunity to try a case again on a different
   theory.” Leverette v. Louisville Ladder Co., 183 F.3d 339, 342 (5th Cir. 1999) (internal
   quotation marks and citation omitted).
           25
              Even the case Butler principally relies on defines with specificity the relevant
   duty applicable to the employment context of that case. See Rando, 16 So. 3d at 1086–87
   (describing specific statutory duties owed by employers pursuant to Louisiana Revised
   Statute § 23:13, industry standards related to asbestos, and the state legislature’s
   “inclusion of asbestosis as an occupational disease” in concluding that the employer owed
   a duty of care to its employee regarding asbestos exposure). So too for each of the cases
   Butler cites. See, e.g., Rathey v. Priority EMS, Inc., 894 So.2d 438, 466 (La. 2005)
   (describing specific duty of care owed by an EMT during a medical emergency); Davis v.
   Witt, 851 So. 2d 1119, 1127–28 (La. 2003) (concluding, in a wrongful death negligence suit
   following a truck collision, that the trial judge erred “because he failed to fit the duty of the
   dispatcher within the parameters the courts of this state have set with regard to law
   enforcement personnel under circumstances that do not constitute an emergency”); id. at
   1128–29 (describing detailed jurisprudential duties of commercial truck drivers); Joseph v.
   Dickerson, 754 So. 2d 912, 916 (La. 2000) (noting that a car owner had a duty, as described
   in the Restatement (Second) of Torts § 390 (1965), not to negligently entrust her vehicle
   to her daughter); Boykin, 707 So. 2d at 1231 (identifying the undisputed and specific duty
   of Department of Transportation and Development “to design and provide a signal-
   controlled intersection that did not present an unreasonable risk of harm to motorists and
   pedestrians”).

                                                  24
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                                           No. 20-30365

   “is whether the plaintiff has any law (statutory, jurisprudential, or arising
   from general principles of fault) to support the claim that the defendant owed
   him a duty.” Id.; accord Boykin v. La. Transit Co., 707 So. 2d 1225, 1230 (La.
   1998) (emphasizing that in a “proper duty-risk analysis” the court should
   first identify “the duty imposed upon the defendant by statute or rule of
   law”). “Whether a legal duty exists, and the extent of that duty, depends on
   the facts and circumstances of the case, and the relationship of the parties.”
   Joseph v. Dickerson, 754 So. 2d 912, 916 (La. 2000).
           Here, Butler relies not on the EPA, OSHA, or other agencies’
   recommended emissions thresholds but on generalized pronouncements that
   Denka has violated its duty to take “reasonable care.” Yet, Butler points to
   no “statutory,” “jurisprudential,” or any other source of law—and we have
   likewise found none—in which such generalized references to “excessive
   emissions,” “acceptable risk threshold,” and “unreasonably dangerous
   emissions,” constitutes a sufficient legal duty to support a negligence or
   custodial liability claim. See Bd. of Comm’rs v. Tenn. Gas Pipeline Co., 850
   F.3d 714, 727–28 (5th Cir. 2017) (dismissing negligence and strict liability
   claims asserting that defendant companies’ dredging caused erosion and
   costly flood protection measures because plaintiffs failed to allege an
   applicable legal duty under the federal and state statutory and regulatory
   schemes governing the state’s waterways). 26

           26
              As it is not before us in this appeal, we express no opinion on the district court’s
   conclusion that the EPA’s or other agencies’ stated acceptable emissions thresholds cannot
   constitute a legal duty under Louisiana law. We also note that there is a dearth of Louisiana
   case law on a defendant’s legal duty regarding the emission of chemicals. None of the
   parties asks us to certify to the Louisiana Supreme Court whether Louisiana law recognizes
   such a duty as alleged here, and we decline to sua sponte certify such a question at this time
   in light of our conclusion that Butler fails to assert any such theory here and has largely
   abandoned the arguments she asserted in the district court. Our ruling here is thus based

                                                 25
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                                          No. 20-30365

           Consequently, we agree with the district court that Butler fails to
   allege a duty, or a breach of such duty, based on Denka’s alleged “excessive”
   chloroprene emissions. Absent a showing of duty or breach, we need not
   address the district court’s alternative holding as to causation or injury. See
   Lemann, 923 So. 2d at 633 (“A negative answer to any of the inquiries of the
   duty-risk analysis results in a determination of no liability.”). Butler’s
   custodial liability claims fail for the same reason. See Tenn. Gas Pipeline Co.,
   850 F.3d at 729.
                                               D.
           Finally, Butler appeals the dismissal of her declaratory relief claims
   against DEQ. 27 Butler alleged that DEQ failed to warn the community of the
   risks of chloroprene exposure, provide notice concerning the high levels of
   chloroprene emissions, and abide by its statutory duties to conduct routine
   sampling and testing of hazardous waste from the PWF. On appeal, she

   on a straightforward application of federal pleading standards: by failing to allege any
   specific duty that has been violated, she fails to state a plausible claim for relief.
   Accordingly, we do not risk an Erie guess as to whether Louisiana law would, “[i]n deciding
   whether to impose a duty in a particular case, . . . make a policy decision in light of the
   unique facts and circumstances presented.” Lemann, 923 So. 2d at 633. See also Mckesson
   v. Doe, 141 S. Ct. 48, 51 (2020) (per curiam) (remanding to certify to the Louisiana Supreme
   Court “novel issues of state law peculiarly calling for the exercise of judgment by the state
   courts” as to whether Louisiana imposes a duty of care on certain speech-related activity
   that is not protected by the First Amendment because the “constitutional issue . . . is
   implicated only if Louisiana law permits recovery under these circumstances in the first
   place”); id. (“[C]ertification is advisable before addressing a constitutional issue”). We
   express no opinion on whether certification would be appropriate in a suitable case.
           27
              Butler does not meaningfully challenge the district court’s dismissal of Butler’s
   negligence claims against DEQ based on its statutory duties pursuant to Louisiana Revised
   Statutes sections 30:2001-02 and 2011-12 and that it allegedly shielded Denka from liability.
   Butler’s vague and unsupported arguments are deemed abandoned on appeal. See Fed.
   R. App. P. 28(a)(8); see also In re Deepwater Horizon, 819 F.3d 190, 194 n.3 (5th Cir. 2016);
   In re Repine, 536 F.3d 512, 518 n.5 (5th Cir. 2008).

                                                26
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                                    No. 20-30365

   asserts that “DEQ is violating Plaintiff’s Louisiana constitutional rights by
   subjecting her to harmful concentrations of chloroprene,” and seeks a
   judgment declaring the same.
          The district court dismissed Butler’s claims against DEQ because she
   failed to comply with the agency’s administrative process, including the
   agency’s authority to issue declaratory rulings prior to seeking a declaratory
   judgment in court, pursuant to Louisiana Revised Statutes section
   30:2050.10(C).
          On appeal, Butler barely acknowledges the district court’s detailed
   explication of the applicable law, regulations, and administrative
   procedures—instead referring to them as “irrelevant.”           Rather, Butler
   cursorily insists that she is entitled to declaratory relief under the Louisiana
   Constitution and Louisiana Code of Civil Procedure Article 1871. Butler
   does not brief how these provisions interact with, let alone supersede, the
   state’s significant regulatory framework, and we need not address such
   inadequately briefed arguments here. Cinel v. Connick, 15 F.3d 1338, 1345
   (5th Cir. 1994) (“A party who inadequately briefs an issue is considered to
   have abandoned the claim.”).
                                         IV.
          For the foregoing reasons, the judgment of the district court is
   REVERSED in part and AFFIRMED in part, and REMANDED for
   further proceedings consistent with this opinion.

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                                     No. 20-30365

   Haynes, Circuit Judge, concurring in part, dissenting in part:
          I respectfully dissent from Sections III.B and III.C of the majority
   opinion and the corresponding portion of the judgment. As the majority
   opinion demonstrates, we lack understanding of Louisiana law on the scope
   of a defendant’s legal duty regarding the emission of chemicals.              To
   determine whether certification is appropriate, we weigh three factors: (1)
   “the closeness of the question[s]”; (2) federal–state comity; and (3)
   “practical limitations,” such as the possibility of delay or difficulty of framing
   the issue. Swindol v. Aurora Flight Scis. Corp., 805 F.3d 516, 522 (5th Cir.
   2015) (quotation omitted). The Rules of the Louisiana Supreme Court allow
   us to certify dispositive questions of Louisiana law on our own accord if there
   is a lack of “clear controlling precedent” from the Louisiana Supreme Court.
   McKesson v. Doe, 141 S. Ct. 48, 50 (2020) (per curiam) (quotation omitted).
   I discuss these points below.
          As demonstrated by the majority opinion, we lack controlling
   precedent concerning this novel and important question of state law, making
   is a “close question.” Indeed, it concedes, “[t]here is a dearth of Louisiana
   case law on a defendant’s legal duty regarding the emission of chemicals.”
   Op. at 25 n.26. The precedent we do have is of limited utility.
          In Rando v. Anco Insulations Inc., 16 So.3d 1065 (La. 2009), the
   Louisiana Supreme Court held that a defendant-employer had a duty to
   protect a plaintiff-employee from exposure to asbestos—despite there being
   no law or regulation at the time of the exposure regarding the harm of
   asbestos—because the defendant “knew or should have known of the
   dangers of asbestos exposure at the time of [the plaintiff’s] employment.”
   Id. at 1087. While Rando is helpful to our analysis (and, frankly, is more
   supportive of Butler’s view than Denka’s), the Louisiana Supreme Court has
   never addressed whether, and to what extent, this duty applies outside of the

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                                       No. 20-30365

   employment law context. 1 A further review of the existing law indicates that
   there are no “clear controlling precedents” from the Louisiana Supreme
   Court that discuss the full scope of this duty. As such, it is appropriate for us
   to certify the question sua sponte.
          The question of whether an emitter has a duty to limit emissions to a
   level it should have known would not harm human health is an important one
   that can substantially affect residents of the particular state, so under our
   federal-state comity, I conclude that we should defer to the Louisiana
   Supreme Court on this topic. Moreover, certification of a question to a state
   supreme court is particularly appropriate where, as here, the dispute presents
   novel issues of state law, calling for the exercise of judgment by the state
   courts. See Lehman Bros. v. Schein, 416 U.S. 386, 391 (1974). As the majority
   opinion notes, Butler’s negligence claim does not rely on any statutory or
   jurisprudential law to establish duty. Rather, Butler relies on the general
   principle that individuals have a duty to take “reasonable care.” Where, as
   here, the plaintiff states a generalized duty, the court must determine
   “whether the rule is intended to protect him from the particular harm
   alleged.” In re FEMA Trailer Formaldehyde Prods. Liab. Litig., 838 F. Supp.
   2d 497, 505 (E.D. La. 2012) (citing Meany v. Meany, 639 So.2d 229, 233 (La.
   1994)).    In doing so, courts “may consider various moral, social, and
   economic factors.” Meany, 639 So.2d at 233. As such, in deciding legal duty
   questions, courts are required to “make a policy decision in light of the
   unique facts and circumstances presented.” Lemann v. Essen Lane Daiquiris,
   Inc., 923 So. 2d 627, 633 (La. 2006).

          1
             Admittedly, Louisiana law provides a more specific legal duty for employers
   towards their employees. See Rando, 16 So.3d at 1086 (citing LA. REV. STAT. ANN.
   § 23:13).

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                                         No. 20-30365

           The determination of a legal duty question presents a paradigmatic
   situation of a case calling for the exercise of judgment by state courts. See
   Lehman Brothers, 416 U.S. at 391. Indeed, the Supreme Court recently
   remanded to the Fifth Circuit to certify a novel question on duty under
   Louisiana negligence law to the Louisiana Supreme Court. See McKesson, 141
   S. Ct. at 51 (2020). At bottom, certification in this case would allow
   Louisiana courts to properly exercise their judgment on novel issues of state
   law.
           Additionally, the question of whether Denka owed Butler a legal duty
   is directly dispositive of Butler’s claims (assuming arguendo that Butler has
   sufficiently pleaded breach, causation, and damages). 2 Therefore, whether
   or not Denka has a legal duty—regarding the emission of excessive chemicals
   that it allegedly should have known could have carcinogenic effects—will
   determine the outcome of this case, with respect to Denka.

           2
             Independent of the certification issue, I respectfully dissent from the majority
   opinion’s conclusion that Butler’s pleadings fail to allege a duty or a breach of such duty.
   Though plaintiffs must plead a “specific standard” of care, Lemann, 923 So. 2d at 633, it
   appears that Butler has done so—contending that “Denka has failed to exercise reasonable
   care to prevent emission of unreasonably dangerous chloroprene concentrations into the
   air where Plaintiff lives.” This standard is hardly new; Louisiana imposes “an almost
   universal duty” on defendants in negligence cases “to use reasonable care.” Rando, 16 So.
   3d at 1086.
           The majority opinion takes issue with Butler’s “generalized pronouncements” of
   a duty; however, whether a legal duty exists under Louisiana law, is dependent “on the
   facts and circumstances of the case.” Joseph v. Dickerson, 754 So. 2d 912, 916 (La. 2000).
   Butler has not had the opportunity to take relevant discovery that could bolster her claims
   and allow her to define with specificity the relevant duty and breach. Therefore, Butler
   cannot be faulted for lacking supporting factual evidence before discovery has even begun.
   As such, Butler’s allegations are sufficient—particularly at the 12(b)(6) stage—to allege
   duty and breach.

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                                         No. 20-30365

           As far as practicality, there is no indication that the Louisiana
   Supreme Court would unduly delay the case—it handles cases promptly.
           In summary, it is surprising to say that, because we do not know what
   the law is on this, we are going to let emitters spew pollution harming
   individuals without recourse. 3           This case therefore has wide-ranging
   implications on future plaintiffs’ ability to pursue similar claims under
   Louisiana law. The majority opinion’s declination to certify this question
   could prevent future plaintiffs from filing suit against alleged environmental
   contaminators, merely because they lack detailed information on the
   emitter’s specific actions prior to discovery.
           For the foregoing reasons, I conclude that we should certify this issue
   to the Louisiana Supreme Court: whether an emitter has a duty (the failure
   of which gives rise to a cause of action by an individual who was harmed) to
   fail to emit pollutants above a level that causes harm to human health. See In
   re Katrina Canal Breaches Litig., 613 F.3d 504, 509 (5th Cir. 2010)
   (“[C]ertification may be advisable where important state interests are at
   stake and the state courts have not provided clear guidance on how to
   proceed.” (quotation omitted)); see also Jesco Const. Corp. v. NationsBank
   Corp., 278 F.3d 444, 448 (5th Cir. 2001) (same). I therefore dissent from
   Sections III.C and III.B and the corresponding portion of the judgment; I
   otherwise concur.

           3
             Because this case is at the Rule 12(b)(6) stage, we must accept the allegations as
   true. Of course, I recognize that, if the Louisiana Supreme Court found that the law
   provides a cause of action, the facts may not be proven or may be contrary to Butler’s
   allegations.

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                                    No. 20-30365

   Andrew S. Oldham, Circuit Judge, dissenting in part:
          I respectfully dissent from section III.A of the majority’s opinion.
   Butler has not met her burden to prove tolling of the prescription period. I
   would affirm the district court’s holding that Butler’s claims against DuPont
   and DOH were time-barred.
          The majority concludes Butler’s injury accrued—and prescription
   began to run—in April 2012 when she began seeking medical treatment. With
   that much, I agree. But the majority then concludes that Butler is entitled to
   tolling of the prescription period because, at the pleadings stage, there is not
   enough evidence to put her on constructive notice that chloroprene was
   responsible for her symptoms. There are five problems with that.
          First, Butler’s own pleadings contained facts sufficient to establish
   constructive notice. Under Louisiana law, constructive notice includes
   “notice of everything to which a reasonable inquiry may lead.” Campo v.
   Correa, 828 So. 2d 502, 511 (La. 2002). And here, Butler alleged numerous
   public facts that any reasonable inquiry would uncover:

   • In 2010, EPA concluded chloroprene is likely carcinogenic.

   • In December 2015, EPA classified chloroprene as a likely human
     carcinogen.

   • In July 2016, EPA held a public meeting in Butler’s community to discuss
     potential chloroprene emission issues.

   • In December 2016, at a school board meeting, the community
     discussed—and community members expressed concern about—local
     chloroprene concentrations.

   • In January 2017, Denka made an agreement with DEQ to reduce its
     chloroprene emissions by 85%.

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                                     No. 20-30365

   • And in April 2017, EPA released a redacted copy of an inspection report,
     which revealed numerous areas of non-compliance at the facility.
          Butler did not file suit until June 5, 2018. So it was her burden to prove
   that tolling lasted until June 5, 2017. But every one of the above facts points
   to an earlier date. Butler’s own petition reveals what a reasonable inquiry
   would have uncovered and when it would have uncovered it.
          Second, the efforts that led Butler to learn these facts by June 2018
   could have led her to discover them sooner. That matters because the
   limitations period is more likely to bar relief when the petition’s allegations
   are “based on the same facts” that the plaintiff “could have discovered had
   [she] investigated” earlier. Marin v. Exxon Mobil Corp., 48 So. 3d 234, 250
   (La. 2010); accord Wells v. Zadeck, 89 So. 3d 1145, 1152 (La. 2012) (noting
   inaction is reasonable when a plaintiff is “prevented from filing [a] claim”
   because the cause of action is not “reasonably knowable by the plaintiff”).
   But there’s nothing to suggest the facts that formed the basis of Butler’s
   petition in 2018 were not reasonably knowable well before then. She doesn’t
   point to anything that would have made these facts undiscoverable until June
   2017. So the very same efforts she eventually made could have been made
   earlier.
          Third, the majority concludes that Butler is entitled to discovery to
   determine “what she learned, and when she learned it.” Ante, at 16. But this
   confuses actual and constructive notice. Any information uncovered in
   discovery only could show Butler’s actual knowledge. But that’s beside the
   point. “It is not necessary to have actual knowledge as long as there is
   constructive knowledge.” Tenorio v. Exxon Mobil Corp., 170 So. 3d 269, 274
   (La. Ct. App. 2015). Butler is “deemed to know” every fact she “could have
   learned with reasonable diligence.” Ibid. Whether and when she did in fact
   know is irrelevant.

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                                      No. 20-30365

          Fourth, the absence of a formal diagnosis can’t rescue Butler’s claims.
   Prescription runs “from the time there is enough notice to call for inquiry
   about a claim, not from the time when the inquiry reveals facts or evidence
   sufficient to prove the claim.” In re Taxotere (Docetaxel) Prods. Liab. Litig., 995
   F.3d 384, 391 (5th Cir. 2021). A medical diagnosis is not a prerequisite—it’s
   just one form of notice. And here, notice came in a different form: As the
   district court concluded, “[s]eeking medical attention for approximately 20
   symptoms consistently for years would put a reasonable person on guard to
   inquire into why she is suffering persistently with so many symptoms.”
   Butler v. Denka Performance Elastomer LLC, 2019 WL 1160814, at *4 (Mar.
   13, 2019). And to the extent Butler argues her symptoms were unexplained
   without a diagnosis, her own allegations again fill the gap: She alleged she
   experienced a fear of cancer from her symptoms and medical treatment. The
   mental link she formed between her symptoms and the possibility of cancer
   was enough to “put [her] on guard and to call h[er] to inquire into the cause
   of h[er] condition.” Tenorio, 170 So. 3d at 275.
          Finally, the majority makes much of the fact that this case is only at
   the pleadings stage. And it rightly notes we must “accept all well-pleaded
   facts as true and view all facts in the light most favorable to the plaintiff.”
   Thompson v. City of Waco, 764 F.3d 500, 502 (5th Cir. 2014). But that makes
   no difference either, because it’s the very facts Butler pleaded that make her
   ineligible for tolling. If we accept all her facts as true, it only establishes that
   she had constructive notice long before she sued.
          For these reasons, Butler cannot meet her burden to prove
   prescription was tolled. She’s pleaded facts that establish constructive notice
   well before she filed suit. And further discovery won’t do anything to erase
   the facts she alleged. I would affirm the district court’s judgment.

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