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Subject: Re: Knutsen PM Data - Response to Request

From: "Knutsen, Synnove (LLU)" <sknutsen@llu.edu>

To: Rebecca Yang/RTP/USEPA/US@EPA

Cc: Lindsay Stanek/RTP/USEPA/US@EPA, Beth Hassett-Sipple/RTP/USEPA/US@EPA

Date: 12/01/2009 03:18 PM

Subject: RE: PM AQD follow-up

Dear Rebecca,

Attached are the data for the PM2.5. We have not been able to do the crude fraction yet, but should be 

able to get it to you within a week or so. 

Synnøve

Synnøve F. Knutsen, MD, MPH, PhD

Professor and Chair

Dept. of Epidemiology and Biostatistics

School of Public Health

Loma Linda University

Nichol Hall, Rm 2003

Loma Linda, CA 92350

Phone: (909) 558-4590

Fax: (909) 558-0326

From: Yang.Rebecca@epamail.epa.gov [mailto:Yang.Rebecca@epamail.epa.gov] 

Sent: Wednesday, November 25, 2009 8:21 AM

To: Knutsen, Synnove (LLU)

Cc: Stanek.Lindsay@epamail.epa.gov; Hassett-Sipple.Beth@epamail.epa.gov

Subject: PM AQD follow-up 

Dear Dr. Synnove Knutsen,

My name is Rebecca Yang and I am writing to you on behalf of Dr. Lindsay Stanek and Ms. Beth 

Hassett-Sipple of the EPA. In May, you wrote that you were working on obtaining the requested 

information for the PM2.5 and PM10-2.5 air quality distribution data for your study listed below . Because 

the PM Integrated Science Assessment will be finalized in mid -December, is it possible for you to send the 

descriptive statistics for your 2005 study by Thursday, December 3rd? 

The statistics of most interest for the 24-hour concentrations of PM2.5 and/or PM10-2.5 are the following: 

- 95th percentile

- 96th percentile

- 97th percentile

- 98th percentile

- 99th percentile

- maximum concentration value 
Because your study contains thoracic coarse PM data, the PM10 data for the same statistics as above are

also requested. 

In respect for your time, if there is another researcher/co-author who may be able to handle this air quality 

data request (i.e., has easier access to the data), I would greatly appreciate his/her name and contact 

information. Please also note that any data you provide will be placed in the EPA's public docket. 

Thank you for your help! I apologize for the inconvenience but the data you provide is critical for inclusion 

in the EPA's Integrated Science Assessment and Policy Assessment Document for Particulate Matter . 

Thank you for your time! I look forward to hearing from you. 

Sincerely,

Rebecca Yang 

Student Services Contractor

U.S. Environmental Protection Agency

National Center for Environmental Assessment-RTP

PH: (919) 541-2655

Chen, L. H., S. F. Knutsen, et al. (2005). "The association between fatal coronary heart disease and ambient 

particulate air pollution: Are females at greater risk?" Environ Health Perspect 113(12): 1723-9. 
Daily estimates of ambient PM2.5 concentration were obtained for 11 airsheds from daily measures of visibility c

California airports for the years 1973-1998 using regression equations relating PM2.5 and visibility. Because of w

provided three separate airsheds (East, West, Central). Detailed methods for PM2 estimation has been described p

al. 1995b). Individual monthly average PM2.5 concentrations were calculated as the mean of the daily ambient PM

airshed in which the participant resided. Any month with PM2.5 estimates for > 75% of the days was considered t

Estimated PM2.5 mean concentration across airsheds, 1973-1998, AHSMOG study 

Percentiles 

Airshed Mean 

Std Deviation Minimum Maximum 95.00 96.00 97.00 98.00 99.00 

Alameda 17.23 10.42 4.78 173.84 35.92 38.79 42.26 47.66 60.24 

San Jose 15.38 13.01 3.77 165.1 41.93 46.47 51.67 59.22 72.42 Bakersfield 26.73 22.35 3.78 277.01 71.27 76.90 85.52 97.33 121.08 Fresno 21.83 17.08 0.25 191.72 54.71 58.17 62.89 69.56 81.98 Los Angeles 24.71 11.55 7.88 134.1 46.01 48.86 52.98 58.40 67.16 Long Beach 25.85 13.95 4.89 168 51.69 55.36 60.31 65.91 75.85 Ontario Central 33.15 16.99 9.02 174.49 65.81 68.64 72.86 79.47 92.67 Ontario East 38.41 20.8 9.93 204.85 77.62 81.37 86.85 93.75 108.75 Ontario West 26.35 12.79 6.14 130.82 50.09 52.38 55.51 60.17 69.86 Sacramento 16.05 10.85 4.58 124.11 38.00 41.15 45.78 53.59 62.51 San Diego 15.2 5.67 5.68 90.16 24.48 25.88 27.81 31.00 36.54 
Estimated PM2.5 mean concentration across airsheds, 1973-1998, AHSMOG study 
Estimated PM2.5 mean concentration across airsheds and years, 1973-1998, AHSMOG study 

 Alameda San Jose Bakersfield Fresno Los Angeles Long Beach 

Ontario 

Central 

Ontario 

East 

Ontario 

West Sa

1973 18.11 15.37 25.33 19.67 28.73 32.56 41.35 49.84 33.03 1974 17.21 16.77 27.04 22.16 27.38 31.13 37.63 45.18 30.48 1975 18.47 17.15 29.49 20.08 27.69 31.24 38.70 46.36 31.29 1976 24.05 21.42 32.80 24.42 26.49 27.41 35.11 42.06 28.69 1977 19.51 17.67 28.21 24.49 27.53 29.64 36.98 44.29 30.15 1978 17.17 18.64 31.33 24.39 26.24 27.16 33.25 39.83 27.50 1979 16.78 18.67 23.99 22.33 26.23 26.90 32.13 38.52 26.51 1980 18.79 20.71 31.19 24.63 28.14 30.31 35.00 41.94 28.70 1981 19.56 17.46 30.65 20.56 27.84 28.66 36.39 43.51 29.72 1982 18.34 16.50 27.80 19.17 26.09 25.79 35.58 42.68 28.91 1983 17.17 13.18 23.86 18.58 26.39 25.31 31.76 38.00 26.38 1984 19.65 13.01 28.26 21.03 25.37 25.07 31.08 37.14 25.86 1985 19.52 16.56 29.19 22.46 26.53 27.65 33.49 40.20 27.68 1986 18.79 16.63 27.42 23.07 25.96 27.44 32.74 39.16 27.08 1987 16.61 14.53 24.34 23.31 24.95 25.42 33.02 39.40 27.19 1988 15.68 14.77 28.95 25.66 25.73 26.46 35.11 42.08 28.78 1989 16.07 16.66 30.19 25.90 26.53 27.76 36.16 43.41 29.45 1990 15.87 15.20 25.28 24.25 24.28 25.55 31.30 37.39 26.00 1991 17.29 16.96 23.97 22.80 26.77 28.22 30.41 36.31 25.47 1992 14.30 14.18 23.49 21.72 24.55 25.26 30.19 36.10 25.23 1993 14.08 11.84 22.78 18.52 19.69 19.56 29.83 31.55 21.86 1994 16.93 11.42 22.42 17.05 17.29 17.57 29.19 28.68 19.59 1995 17.15 12.08 24.92 19.35 19.33 20.98 31.76 32.36 22.41 1996 14.59 10.33 22.85 21.04 18.26 19.80 28.28 27.98 19.33 1997 13.47 9.27 24.31 20.17 18.50 19.18 27.01 26.39 18.20 1998 13.02 12.44 24.83 20.17 19.14 19.24 28.97 28.96 20.08