OPINION OF THE COURT
Smith, J.The United States Court of Appeals for the Second Circuit has asked us three questions about the interpretation of CPLR 214-c (4), which extends the statute of limitations for certain *594tort victims who do not, for some time, know the cause of their injuries. We answer the questions by holding that:
(1) the provisions of CPLR 214-c (4) are limited to actions for injuries caused by the latent effects of exposure to a substance;
(2) an injury that occurs within hours of exposure to a substance can be considered “latent” for these purposes; and
(3) “technical, scientific or medical knowledge and information sufficient to ascertain the cause of [the plaintiffs] injury” is “discovered, identified or determined” within the meaning of the statute when the existence of the causal relationship is generally accepted within the relevant technical, scientific or medical community.
I
Plaintiff suffered a series of strokes in March of 1999. The strokes were caused, we assume for present purposes, by ephedra, a substance contained in a dietary supplement that plaintiff had been using for about two years. Ephedra causes in some users a short-term elevation in blood pressure, heart rate or both, and a temporary constriction of certain blood vessels. This effect, which increases the risk of stroke, typically occurs within a few hours after ephedra is consumed.
Neither plaintiff nor the doctors who treated him for his strokes knew at the time that ephedra was to blame. When they could, or reasonably should, have known of the causal connection is disputed. The United States District Court for the Southern District of New York has found that studies published as early as 1996 suggested a link between ephedra and stroke, but that as late as 2005 scientific evidence did not establish the link “with any degree of medical or scientific ‘certainty’ ” (In re Ephedra Prods. Liab. Litig., 598 F Supp 2d 535, 536 [SD NY 2009]).
Plaintiff claims that he became aware of a possible link between ephedra and stroke in February 2003, when news reports suggested that the sudden death of a major league baseball player might have been caused by ephedra. On July 28, 2003— about four years, four months after his strokes—plaintiff sued the distributor of the product he had taken in New York State Supreme Court. The case was removed to federal court, the manufacturer of the product was added as a defendant, and the case was consolidated with other ephedra-related litigation in the Southern District of New York.
*595Defendants moved to dismiss the case as barred by the statute of limitations, relying on CPLR 214 (5), which imposes a three-year limitation period, with certain exceptions, on “an action to recover damages for a personal injury.” It is undisputed that the claim is barred by CPLR 214 (5) unless it is saved by the exception in CPLR 214-c (4), which we quote in the next section of this opinion.
Defendants’ statute of limitations motion generated a series of opinions in the District Court and the Second Circuit. Initially, the District Court granted the motion to dismiss (In re Ephedra Prods., 2006 WL 944705, 2006 US Dist LEXIS 18691 [SD NY 2006]). Plaintiff appealed to the Second Circuit, which remanded the case for determination of an issue the District Court had not reached (Giordano v Market Am., Inc., 289 Fed Appx 467 [2d Cir 20083). Following the District Court’s ruling on that issue (In re Ephedra Prods. Liab. Litig., 598 F Supp 2d 535 [SD NY 2009]), the Second Circuit certified to us the three questions that we now address (Giordano v Market Am., Inc., 599 F3d 87 [2d Cir 2010]).
II
Directly in issue here is subdivision (4) of CPLR 214-c, which refers to subdivisions (2) and (3) of the same section. The text of the three relevant subdivisions is:
“2. Notwithstanding the provisions of section 214, the three year period within which an action to recover damages for personal injury or injury to property caused by the latent effects of exposure to any substance or combination of substances, in any form, upon or within the body or upon or within property must be commenced shall be computed from the date of discovery of the injury by the plaintiff or from the date when through the exercise of reasonable diligence such injury should have been discovered by the plaintiff, whichever is earlier.
“3. For the purposes of sections fifty-e and fifty-i of the general municipal law, section thirty-eight hundred thirteen of the education law and the provisions of any general, special or local law or charter requiring as a condition precedent to commencement of an action or special proceeding that a notice of claim be filed or presented within a specified *596period, of time after the claim or action accrued, a claim or action for personal injury or injury to property caused by the latent effects of exposure to any substance or combination of substances, in any form, upon or within the body or upon or within property shall be deemed to have accrued on the date of discovery of the injury by the plaintiff or on the date when through the exercise of reasonable diligence the injury should have been discovered, whichever is earlier.
“4. Notwithstanding the provisions of subdivisions two and three of this section, where the discovery of the cause of the injury is alleged to have occurred less than five years after discovery of the injury or when with reasonable diligence such injury should have been discovered, whichever is earlier, an action may be commenced or a claim filed within one year of such discovery of the cause of the injury; provided, however, if any such action is commenced or claim filed after the period in which it would otherwise have been authorized pursuant to subdivision two or three of this section the plaintiff or claimant shall be required to allege and prove that technical, scientific or medical knowledge and information sufficient to ascertain the cause of his injury had not been discovered, identified or determined prior to the expiration of the period within which the action or claim would have been authorized and that he has otherwise satisfied the requirements of subdivisions two and three of this section.”
The three questions that the Second Circuit has asked us are
“1. Are the provisions of N.Y. C.RL.R. § 214-c(4) providing for an extension of the statute of limitations in certain circumstances limited to actions for injuries caused by the latent effects of exposure to a substance?
“2. Can an injury that occurs within 24 to 48 hours of exposure to a substance be considered ‘latent’ for these purposes?
“3. What standards should be applied to determine whether a genuine issue of material fact exists for resolution by a trier of fact as to whether ‘technical, *597scientific or medical knowledge and information sufficient to ascertain the cause of [the plaintiff’s] injury’ was ‘discovered, identified or determined’ for N.Y. C.EL.R. § 214-c(4) purposes?” (599 F3d at 101.)
We answer yes to both of the first two questions; thus, our answers are favorable to defendants on question one but to plaintiff on question two. We answer question three by saying, as we explain more fully below, that the test is one of general acceptance in the relevant technical, scientific or medical community.
Question One: Is the statute limited to injuries caused by latent effects?
CPLR 214-c (2), providing a statute of limitations that runs “from the date of discovery of the injury ... or from the date when . . . such injury should have been discovered,” is expressly restricted to cases of injury “caused by the latent effects of exposure to any substance or combination of substances.” CPLR 214-c (3), relating to notice of claim requirements, contains an identical restriction. The Second Circuit’s first question is, in essence, whether the same restriction is incorporated into CPLR 214-c (4), governing cases in which “discovery of the cause of the injury” was allegedly delayed. We conclude that it is.
CPLR 214-c (4) mentions “subdivisions two and three of this section” three times. The third mention, we conclude, answers the Second Circuit’s question: “[T]he plaintiff or claimant shall be required to allege and prove . . . that he has otherwise satisfied the requirements of subdivisions two and three of this section.” Since subdivisions (2) and (3) require that the claim or action be one for injury “caused by the latent effects” of exposure, subdivision (4), on its face, also imposes a latency requirement.
Even if subdivision (4) could be read otherwise—if it could be read as creating an independent exception to the general three-year statute of limitations, not one dependent on the provisions of subdivisions (2) and (3)—such a reading would be inconsistent with the statute’s history and purpose. CPLR 214-c was enacted in 1986 to give relief to plaintiffs in certain toxic tort cases. Its legislative history, which we discussed in Matter of New York County DES Litig. (89 NY2d 506, 513-514 [1997]), shows that it was intended to overrule decisions in which we had held that toxic tort claims accrued upon exposure, even *598though the illness resulting from that exposure might be long delayed (see e.g. Fleishman v Lilly & Co., 62 NY2d 888 [1984]; Schwartz v Heyden Newport Chem. Corp., 12 NY2d 212 [1963]). The Legislature’s concern when it enacted the statute was the problems raised by toxic tort cases in which the latency of a substance’s effect could prevent the plaintiff from bringing a timely lawsuit.
Plaintiff stresses that the word “latent” does not appear in CPLR 214-c (4). Indeed, the words “exposure to any substance” do not appear there either. But the whole point of CPLR 214-c was to deal with substance exposure cases. No other kind of case is discussed in the legislative history, and the Governor, when he signed the bill, identified it as the “Toxic Tort Bill” (see Public Papers of Governor Cuomo, Governor Approves Toxic Tort Bill [July 30, 1986]). It can hardly be argued, and plaintiff does not argue, that CPLR 214-c (4) extends beyond substance exposure cases—that for example, it would benefit a plaintiff injured by a hit and run driver or an unidentified falling object. It is thus undisputed that the words “exposure to any substance” in subdivisions (2) and (3) are incorporated into subdivision (4) of CPLR 214-c. We see no possible reading of the statute under which those words are incorporated but the word “latent” is not.
Question Two: Can an effect that appears within a matter of hours be considered “latent”?
While we think it clear that CPLR 214-c (4) is limited to injuries from “latent effects,” whether effects that are concealed only briefly count as “latent” is a harder question. The Second Circuit’s question to us implies that the harmful effects of ephedra show themselves within “24 to 48 hours of exposure.” Opinions of the District Court suggest that the time may be even shorter—a matter of a “few hours” (In re Ephedra Prods. Liab. Litig., 393 F Supp 2d 181, 193 [SD NY 2005]; see also In re Ephedra Prods., 2006 WL 944705, *1, 2006 US Dist LEXIS 18691, *3). This discrepancy need not concern us, because we conclude that even effects concealed for a few hours may be “latent” within the meaning of the statute.
The dictionary definition of “latent” is “not now visible, obvious, active, or symptomatic” (Merriam-Webster’s Collegiate Dictionary 702 [11th ed 2003]). Using that word to describe a condition that exists only for hours puts no strain on its literal meaning. But in interpreting this statute, it might intuitively seem that so brief a period of latency should be disregarded as *599insignificant—that, as the District Court put it in its opinion granting defendants’ motion to dismiss, to treat the stroke-causing effects of ephedra as latent “would effectively eliminate the statute’s limitation to ‘latent effects’ ” (In re Ephedra Prods., 2006 WL 944705, *1, 2006 US Dist LEXIS 18691, *4). In fact, however, even a brief period of latency can be important when the problem is one of determining an injury’s cause—the problem with which CPLR 214-c (4) is concerned.
Perhaps the task, often confronted by doctors or scientists, of finding a causal connection between exposure to a toxic substance and an injury is never an easy one. It is certainly less difficult, however, when the effect of the toxic substance can be seen immediately—when, for example, someone breaks out in a rash as soon as his skin touches a suspected toxin. Or, to suggest an example closer to this case, if plaintiff had suffered symptoms of a stroke at once upon swallowing a pill containing ephedra, his chances and those of his doctors of inferring the causal link would have been immeasurably better. Indeed, if that had occurred, it seems highly likely that plaintiff could have discovered the cause of his injury within the normal three-year limitation period. But because his symptoms showed themselves hours later, it may have been very hard to say whether ephedra and the strokes were causally connected.
Thus cases where a toxin’s effects are latent for hours are much more likely than those in which there is no latency period to present the problem addressed by CPLR 214-c (4): a difficulty in promptly learning the cause of an injury. It is entirely plausible that several hours’ delay in the manifestation of symptoms could lead to a delay of years in detecting an injury’s cause. It thus seems reasonable that the authors of CPLR 214-c (4) would have considered even a few hours of latency enough to justify the extension of the statute of limitations authorized by that subdivision.
Defendants, and our dissenting colleagues, argue otherwise, contending that, as we said in New York County DES, the legislative history of CPLR 214-c shows that the Legislature that enacted it was concerned with long-term latency—with plaintiffs who were unaware that they had been injured “until after the limitations period had expired” (89 NY2d at 514 [internal quotation marks omitted]). There is no doubt that the problem of injuries that go undiscovered for years was the Legislature’s primary concern. But that was not its sole concern, for if it was there was no need to enact subdivision (4) of CPLR *600214-c at all. That subdivision benefits only those plaintiffs and claimants who, having already discovered they were injured, have not discovered “the cause of the injury.” A few hours of latency might well cause a plaintiff to be in such a predicament—as plaintiff here says he was.
Defendants, and the dissenters, argue in substance that the benefits of CPLR 214-c (4) should be afforded only to those plaintiffs and claimants who also benefit from CPLR 214-c (2) or (3)—i.e., those who cannot discover their injury within the limitations period. But the statute does not say that, and we see no reason to read it in that way. Defendants’ and the dissent’s reading would produce anomalous results. Those who benefit from subdivisions (2) and (3) may bring suits or make claims many years, even decades, after their exposure to a substance. For such plaintiffs and claimants, it is undisputed, the already-long delay can be extended by subdivision (4) for up to another six years (five years from the discovery of the injury to the discovery of its cause, plus another year to sue or file a claim). But defendants and the dissenters would deny the benefit of subdivision (4) to plaintiffs, like the present one, whose injuries are discovered within hours of exposure—even though subdivision (4) would effectively require those plaintiffs to sue no more than six years after that exposure.
In other words, for plaintiffs like the present one, subdivision (4) would replace the three-year tort statute of limitations with at most a six-year statute—an extension less generous to plaintiffs, and risking less hardship to defendants, than the indefinite extensions that can result from long-term latency. Defendants and the dissent would have us read the statute to countenance extremely old claims, but to bar relatively fresh ones. We reject that reading.
Question Three: What standards apply to the issue of when sufficient information “to ascertain the cause” of an injury has been “discovered, identified or determined”?
The Second Circuit’s third question arises from CPLR 214-c (4)’s requirement that plaintiff “allege and prove that technical, scientific or medical knowledge and information sufficient to ascertain the cause of his injury had not been discovered, identified or determined” before the expiration of the otherwise-applicable limitation period. That question calls on us to resolve two possible ambiguities noted by both the District Court and the Second Circuit: Is it the plaintiff and his lawyers or the technical, scientific or medical community that must be able to *601“ascertain the cause of his injury”? And what level of certainty is implied by the word “ascertain”? Both aspects of this question have been previously addressed by New York courts.
As to the first of them, we said in New York County DES: “It is apparent from the over-all statutory plan . . . that only the technical knowledge of the scientific and medical communities [was] to be considered in determining whether the injured’s delay following the discovery of injury should be excused” (89 NY2d at 515). We now reaffirm that the statute refers to the time when information is sufficient for the technical, medical or scientific community “to ascertain” the cause of an injury. It is not reasonable to extend the statute of limitations until the time when a reasonable layperson or lawyer could “ascertain” the cause without consulting an expert—in many cases, that time might never come. Plaintiff suggests that the statute of limitations in his case did not begin to run until the relevant scientific findings were publicized in the non-expert community, but the statute’s language does not create a “publicity” test. We see no unfairness in requiring that injured people who want to protect their rights seek out expert advice, rather than waiting for the media to bring a possible cause of the injury to their attention.
The other aspect of the Second Circuit’s third question—the issue of what level of certainty “to ascertain” implies—is not one we have previously discussed. We generally agree, however, with the Appellate Division’s comments on that issue in Pompa v Burroughs Wellcome Co. (259 AD2d 18 [3d Dept 1999]). The statute “does not require medical certainty or information sufficient to prevail at trial, but does entail showing that sufficient information and knowledge existed to enable the medical or scientific community to ascertain the probable causal relationship between the substance and plaintiffs injury” (id. at 24).
Making the Appellate Division’s “probable causal relationship” test a bit more specific, we hold that the test, is one of general acceptance of that relationship in the relevant technical, scientific or medical community. That test is familiar to New York lawyers and judges. Our courts follow Frye v United States (293 F 1013 [DC Cir 1923]) in making “general acceptance” the test for admitting expert testimony about scientific principles or discoveries (see People v LeGrand, 8 NY3d 449, 457 [2007]; People v Wesley, 83 NY2d 417, 422 [1994]). Thus, under our holding today a causal relationship will be sufficiently ascertained for CPLR 214-c (4) purposes at, but not before, the *602point at which expert testimony to the existence of the relationship would be admissible in New York courts.
The above, we believe, answers the Second Circuit’s third question: “What standards should be applied?” We have not been asked to, and do not, apply those standards to the facts of this case. The federal courts dealing with this and related cases are more familiar than we with the science relating to the effects of ephedra, and are thus better able to perform that task.
Accordingly, the first and second questions should be answered in the affirmative, and the third question should be answered in accordance with this opinion.