Review of the Air Quality Criteria Document for Particulate Matter

- Page 4-113, lines 13 through 19 focuses on CVM, but really is about stated preferencemethods, including CVM applications. Some of the past economic studies are more like SPchoice studies than conventional CVM applications. Consequently, it may be appropriate tomerge the paragraphs starting on lines 13 and 20.- Page 4-113, line 19 could use a citation, either NAPAP or Chestnut and Dennis, or Mitchelland Carson.- Does the Hanley and Spash reference discuss visibility applications in specific and in detail?- Page 4-113, line 31. “Davis” should be “Dennis”.Health Risk Assessment (Staff paper Chapter 4 and separate paper).- I support conducting the assessment in more than 2 locations, as discussed at the meeting.- Staff paper 4-13, lines 10-26 discusses assumptions about changes in ambient conditions tomeet standards, relying predominately on the rollback method. Using the rollback method isreasonable, but EPA should give careful attention to the proposed sensitivity analysis ofalternative adjustments (lines 24-26). With increasing costs of compliance, episodic andother control strategies that reduce the highest concentrations may receive increasedattention. Further, given that the population exposed is not uniform across concentrationlevels, and many concentration-response functions are non-linear, differences in theassumptions to reduce concentrations to achieve standards can have a significant impact onthe risk assessment.- Deck et al, 2001 is cited several times, starting in the first paragraph, but is not available. Itmay be useful to provide this paper for this review.Criteria Document Chapter 9This chapter is well done as a series of separate summaries, but it needs more integrationand needs to be reduced in length – not everything needs to be summarized. It appropriatelyfocuses on the larger questions of increasing consistency in the results of available health effectsliterature and extensions to this literature. In terms of the important question of retaining orrevising the existing PM 2.5 standard levels (15 ug/m3 annual average and 65 ug/m3 24 hours),little is presented in this chapter on the strength of the evidence, shapes of the estimated C-Rfunctions around these levels, or effect thresholds (although this is touched on in Section 6.4.6).Jonathan Samet, MDChapter 5 - General Comments:In general, this is a cohesive and thorough chapter that carefully sets out concepts of exposureassessment, measurement approaches, and findings. The literature review appears complete andfindings are well represented in tables and in the text. The chapter has a potentially key role insetting a framework for interpreting the epidemiological data presented in Chapter 6. Thechapter does address the implications of the exposure literature for interpreting theepidemiological evidence. Unfortunately, there is little linkage between the two chapters in thisregard; Chapter 6 almost reads as though Chapter 5 had not preceded it. There is a need forbetter integration, a burden which clearly lies with the authors of Chapter 6.This chapter also discusses issues related to confounding and measurement error that overlapwith Chapter 6. With regard to issues of confounding, it will be important to have a uniformview throughout the CD. My comments for Chapter 6 should be considered in this regard.A - 73