Skip to main content

Currently Skimming:

Ninth Interim Report of the Subcommittee on Acute Exposure Guideline Levels
Pages 1-32

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 1...
... AEGEs are needed for prevention and emergency response planning for potential releases of EHSs either unintentionally from accidents or as a result of terrorist activities. THE CHARGE TO THE SUBCOMMITTEE The NRC convened the Subcommittee on Acute Exposure Guideline Levels to review the AEGL documents approver!
From page 2...
... At very high inhaler! concentrations rodents exhibit much higher blood methanol concentrations than do primates.
From page 3...
... Many of the occupational exposure cases likely involved percutaneous exposure as well as inhalation exposure. it is not clear whether a lethal or even a sublethal blood level can be achieved solely Tom inhalation.
From page 4...
... Exposure levels and conditions are not known. There is considerable information from human experiences to pinpoint chronic inhalation LOAELs for humans and cynomolgus monkeys at approximately 1,200 and 1,000 ppm, respectively.
From page 5...
... Is vaginal bleeding a sign of developmental toxicity? It is not stated what vapor concentrations produced vaginal bleeding or possibly resulted in a wasting syndrome.
From page 6...
... ~996) , nor does folate deficiency alter blood methanol concentrations (Lee et al.
From page 7...
... Much higher blood methanol levels are reached in mice during inhalation exposures, due largely to their more rapid respiratory and cardiac output rates. Metabolic clearance rates are species-dependent mice rely on the catalase pathway, while humans rely primarily on the zero-order alcohol dehydrogenase pathway.
From page 8...
... There is considerable clinical information from human ingestion case reports on blood methanol levels associated with different manifestations of acute poisoning. From clinical practice, it is known that blood levels <100 mg/L do not lead to acute or chronic toxicity.
From page 9...
... that are associated with clinically significant but reversible symptoms. A validated PBPK model could then be used to forecast the inhaled methanol concentrations that are required to produce such blood levels in humans for each AEGL-3 time period.
From page 10...
... The report used as the key study was that from which the lowest fatal peak blood methanol concentration was determined. COMMENTS ON ACRYLIC ACID At its January 27-29, 2003, meeting, the subcommittee reviewed the AEGE document on acrylic acid.
From page 11...
... It is an unusual approach to calibrate a total hydrocarbon analyzer to an infrared instrument. Generally, standards are generated and the total hydrocarbon analyzer response is measured for a known concentration.
From page 12...
... , and is not systemic, the authors discount using the toxicokinetic component of the default UF. In addition, the authors dispense with the toxicodynamic component of the UF because the effects were likely seen in a sensitive subpopulation of workers, accounting for potential variability in tissue response amongst humans.
From page 13...
... COMMENTS ON CROTONALDEHYI) E At its January 27-29, 2003, meeting, the subcommittee reviewed the revised AEGL document on crotonaldehyde.
From page 14...
... Major Comments The emergency response planning guideline (ERPG) values are far more consistent with the phenol toxicologic profile in the present context than are the AEGL values proposed in the NAC draft.
From page 15...
... Under what conditions (oral bolus, inhalation, drinking water) was it that "no teratogenic effects tsigns of developmental toxicity?
From page 16...
... As written, the following phrase conflicts with the SOP: "An uncertainty factor of 3 was applied for interspecies variability because a multiple exposure study was used for derivation of AEGL." Certainly a subchronic or repeat-dose protocol that demonstrated neither clinical nor hematological nor histoapthological changes at 0.5-25 ppm would have greater (not reduced) confidence than those same results found after only a single exposure at the same concentration?
From page 17...
... Page 7, line 26. From what section of the SOP was an uncertainty factor of 3 assigned because "variability for lethal effects Does this mean there is no significant difference in LD50 values across species?
From page 18...
... Have this document's authors made a distinction between chromodacyorrhea and red nasal discharge? Stressed rats commonly show evidence of chromodacyorrhea (i.e., red pigment)
From page 19...
... The data should be summarized to indicate clearly that signs of developmental toxicity in rats were evident only after doses that also produced overt maternal phenol intoxication. Page 22, lines 10-13.
From page 20...
... It should be pointed out that the "red nasal discharge" was very likely a manifestation of chromodacYorrhea. As mentioned previously, the presence of this pigment around the eyes and nares is commonly seen in stressed rats.
From page 21...
... This information should be deleted. It makes no sense to consider or to support AEGL-2s based on no-effect exposure levels in a subacute study (i.e., that of Hoffman et al.
From page 22...
... cardiac output rates than do humans, so the rats' systemically absorbed dose (and toxicity) would be substantially greater than that of humans at the same vapor exposure level.
From page 23...
... The NAC shouIc3 reconsider the human data and review the basis for other exposure values, such as the current REL, TEV, PEL, and MAC values for phenol.
From page 24...
... COMMENTS ON CYCLOHEXYLAMINE At its January 27-29, 2003, meeting, the subcommittee reviewed the revised AEGL document on cyclohexylamine. The document was presented by Sylvia Milanez of Oak Ridge National Laboratory.
From page 25...
... All previous comments of the Subcommittee have been addressed. The subcommittee recommends that the section on data quality and research needs be revised to emphasize the limitations of the available data and the need for specific studies to be conducted to strengthen the existing database.
From page 26...
... do not seem to support that hypothesis. The second is that the discussion of the methodology used to convert COHb values to ppm and mg/m3 ignores the substantial individual variation that exists in COHb levels in subjects exposed to CO and the difficulty of obtaining reliable data in the field.
From page 27...
... It will help the reader understand the discussion in the text that refers only to COHb levels and not to ambient exposure levels of CO. ES, page viii, lines 5-~.
From page 28...
... Since final AEGL values are in ambient ppm values, data and discussion should include ppm values as well as COHb values. Page 7, line 22.
From page 29...
... Tell the reader that time scaling is not going to be used in this instance, provide the reason for that decision, and then go into discussion of the model. Page 40, Summary Table.
From page 30...
... The document can be finalized after the recommended revisions have been made properly. COMMENTS ON PROPYLENIMINE At its January 27-29, 2003, meeting, the subcommittee reviewed the AEGE document on propylenimine.
From page 31...
... COMMENTS ON CHLORINE DIOXIDE At its January 27-29, 2003, meeting, the subcommittee reviewed the AEGL document on chionne dioxide (CD)
From page 32...
... The subcommittee believes that there is a possibility/likelihood that reactive oxygen moieties may be generated upon contact of CD with the moist mucus membranes of the upper respiratory tract (URT)


This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More information on Chapter Skim is available.