Review of the Air Quality Criteria Document for Particulate Matter

More documents

Recommendations

Info

P 7- 6, L 15: Are particles charged either negatively or positively? If so, are there charges thatreduce deposition as well as those that enhance it?P 7- 7, L 10: By definition, if a particle is in the “inspired volume” it is inhalable. Conversely,if a particle is not inhalable, it won’t be in the inspired volume. This sentence should read“—particle present in the ambient air”.P 7-9, L 1-13: For these citations, state whether the exposure is nasal, oral, or both. That makesa big difference for ultrafines, and the smaller the particle, the greater difference it makes.P 7- 14, L 24 – P 7-15, L 3: You need to state that these are estimates from models, not actualmeasurements, and you also need to state the type of model used.P 7-15, L 11-12: The sentence implies that there geographical areas where coarse PM are notpresent. Where would such an area be?P 7-15, L 29: Again, do not use the word “aerosol” for “particle”.P 7- L 17: Once again, it’s “particle” not “aerosol”.P 7-19, L 5: Give the geometric standard deviation for the ROFA.P 7-19, L 18: Throughout the chapter, you should state whether the exposures were nasal, oral,or both. This is an important variable, and deposition really can’t be understood without thisinformation.P 7- 22, L 3: This study measured total deposition, not “lung” deposition.P 7- 22, L: It is not clear how a tumor would increase diffusion deposition.P 7-24, L 13: It is not clear what the “shallow region of the lungs” would be. Would this be thecentral airways?P 7-25, L 14: Of course inhalability can be important for humans. It’s important in a dust storm.It’s important if you are riding a motorcycle (remember the old joke about bugs in the teeth).P 7-25, L 25-26: What does “upper and lower airway bifurcations” mean?P 7-26, L 6-7: Just say “—generation is constant” rather than “adopts a constant value”. It’shard to see how an airway generation can adopt anything.P 7- 26, L 14-20: A figure would help the reader understand what you are saying aboutdeposition minima and maxima. A simple line graph showing fractional deposition with particlesize for humans and rats, for example, would be useful.P 7- 27, L 9: Mention whether or not these model predictions have been validated.P 7- L 14: First, it’s the MMAD of the particle size distribution, not the “aerosol” distribution.Second, give the geometric standard deviation of the size distribution.A - 21
P 7- 27, L 15: What does “comparable respiratory intensity levels” mean? I don’t know what“intensity level” might imply.P 7- 27, L 22: Again, has there been any validation? It is important throughout the chapter toindicate whether or not models have been validated against actual measurements.P 7-28, L 9: The statement is incorrect. The study did not measure the “volume density ofdeposition”, whatever that might be. The study measured, using a morphometric techniquebased on volume density, the retained material. A post hoc study of tissue cannot evaluatedeposition, but only the amount and location of retained material.P 7- 28, L 12-14: The statement is incorrect. It is not true that “different cells contact retainedparticles” in the two species. The difference was not absolute. There was relatively morematerial in the interstitium in one species and relatively more in the alveolar lumen in the other,but there was some material in both compartments in both species.P 7- 28, L 21: The point is that there can be greater differences between abnormal humans andnormal rats. The present wording doesn’t convey this; it suggests that the greater difference youare talking about is between humans and rats.P 7-28, L 23-27: This section inappropriately brings response into the dosimetric picture. Doseis dose regardless of response – these are related, but separate, issues. Interspecies doseextrapolation per se has nothing to do with interspecies differences in response or dose-responserelationships. Comparative response has to do with both differences in both dose and response,but comparative dose has nothing to do with differences in response.P 7.29, L 3: In summary, this section could greatly benefit from some tables or figures showingexample results and comparisons. It also needs attention to which model predictions have beenvalidated.P 7-32, L 23-24: The magnitude of response also has to do with PM composition, not just withparticle number.P 7- 33, L 1-11: Lymphatics should be mentioned in this paragraph.P 7- 33, L 14: Do you mean 5% by mass or number?P 7- 33, L 17-18: Alveolar surface fluid is also transported, at least in some in part, up theairways. Surfactant of alveolar origin has been reported in the surface fluid of conductingairways. If this is true, then you should mention this path rather than implying that all PMderivedmaterial solubilized in alveolar fluid is absorbed through the epithelium.P 7-34, L 8: What do you mean by “nonuniform”? Do you mean spatially or temporally nonuniformwithin individuals, or are you referring to variability among individuals?P 7- 35, L 5: You need to clarify throughout this chapter whether the statements aboutdeposition site are derived from measurements or whether these are assumptions from depositionmodels. Most, if not all, are from the latter, which assume plug flows that are not likely to beabsolute.P 7-35, L 22: Deposition was “estimated”, not “calculated”. The latter term implies a certainty,or direct measurement, that doesn’t exist here.P 7-37, L 25-26: The phagocytic activity need not necessarily be decreased, it could be simplyoverwhelmed. More particles could reach the interstitium because of either or both effects.A - 22
Page 5: known, the potential causes deserve
Page 10: SCIENCE ADVISORY BOARD STAFFMr. A.
Page 13 and 14: Page 2-77, line 19-22: Should menti
Page 15 and 16: Page 8-1, lines 26-28: Combustion a
Page 17 and 18: mode vs. the other. In fact, such k
Page 19 and 20: p. 7-49, l. 20 In an effort to make
Page 21 and 22: ambient PM effects. The paragraph d
Page 23 and 24: dominant, one criticism is that “
Page 25 and 26: 6. Susceptible sub-populationsIt is
Page 27 and 28: is OK. But in most settings it stil
Page 29 and 30: 2. There are repetitions of the sam
Page 31: 15. Page 3-57 and 3-58, line 29-31
Page 35 and 36: there is pertains almost solely to
Page 37 and 38: studies, and is presented as observ
Page 39 and 40: P 8-47, L 23-27: These two sentence
Page 41 and 42: also be summarized. Second, the cha
Page 43 and 44: P 9-76, L 30: It should be “these
Page 45 and 46: 4. Page 4-7,lines 14-18. Similar th
Page 47 and 48: control when it may be possible to
Page 49 and 50: 1990. Reference Lioy, P.J. “The A
Page 51 and 52: document.P. 5-82, Lines 15-30 Need
Page 53 and 54: 7-12 8 insert "that are either very
Page 55 and 56: 8-62 10,11 The preceding discussion
Page 57 and 58: 9-27 17 insert "source and/or" afte
Page 59 and 60: 2. The paper by Künzli et al. on t
Page 61 and 62: 6-243 12 This section (6.4.4.) shou
Page 63 and 64: Chapter 5. Human Exposure to PM and
Page 65 and 66: the chapter. Many of the poor quali
Page 67 and 68: Page 5-17, equation 5-10; the coeff
Page 69 and 70: illustrated using a figure from Kel
Page 71 and 72: tied back to the base-line health s
Page 73 and 74: Page 7-4, Structure of the Respirat
Page 75 and 76: Günter Oberdörster, PhDChapter 7
Page 77 and 78: efficiencies as well as the ratio o
Page 79 and 80: The title of this section is also s
Page 81 and 82: old and young rats and mice used on
Page 83 and 84:
passive use values as opposed to us
Page 85 and 86:
Specific Comments:Page 5-19, lines
Page 87 and 88:
Chapter 9 - General CommentsThis ch
Page 89 and 90:
George Taylor, PhDAir Quality Crite
Page 91 and 92:
atmospheric stressors associated wi
Page 93 and 94:
“At the surface, a variable fract
Page 95 and 96:
that point from this review! “Vis
Page 97 and 98:
6. P 2-86, section 2.2.5.1 - A shor
show all

Review of the Air Quality Criteria Document for Particulate Matter

Create successful ePaper yourself

Delete template?

Save as template?