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P. 1 TSCA Document Processing Center August 10, 2006 Attn : Section 8(e)/FYI Page 5 of 10 Attachment 2 ~226_37 38 Tables and excerpts from the draft protocols that contain information related to C-8 blood levels . Table 1 . Descriptive statistics for the community cohort age>=20 a t baseline in 2005 (n=23,942) Mean age in 2005 46 Age <20 20% Age 20-39 31% Age 40-49 18% Age 50-59 15% Age 60-69 10% Age 70+ 6% Median Body Mass Index 27 .9 Mean C8 level 130 ppb Median C8 level 48 ppb Percent >=60 yrs age 20% Percent BMI>=30 36% Percent white 98% Percent male 46% Percent current smokers 26% Percent finished college 13 % Table 2 . Anticipated distribution of C8 in study participants . C8 median 48 ppb C8 mean 130 ppb C8 <10 ppb 8% 10-49 43% 50-99 20% 100-149 9% 150-199 5 % 200-299 5% 300-550 5 % 505+ 4% p. 2 TSCA Document Processing Center August 10, 2006 Attn : Section 8(e)/FYI Page 6 of 10 Table 1 . Descriptive data on subjects>age 20 (n=23,942 ) Age 20-39 38% 40-49 23% 50-59 19% 60-69 12% 70-79 6% 80+ 2% White 98% Female 54% Current smoker 26% Schoo l <12 11% High School/GED 43% Some College 34% College degree 12% C8 median 48ppb C8 mean 130ppb C8 <10 ppb 8% 10-49 43% 50-99 20% 100-149 9% 150-199 5% 200-299 5% 300-550 5% 550+ 4 % BMI mean 28 .9 BMI median 27 .9 BMI 30+ 30% % prevalent heart disease 8 .5% % prevalent stroke 2% Cholesterol mean 200 mg/d l Cholesterol median 196 mg/dl p. 3 TSCA Document Processing Center August 10, 200 6 Attn : Section 8(e)/FYI Page 7 of 10 Table 3 .2 Blood C8 in participants by water district reported a s source of drinking water (last address, ignoring those not reporting one of the six water districts as source) . Mean, median and 10th and 90th percentiles . (Units ug/1). Distr ict of last address (DW) N mean(c8) med c8 10 c8 p90(c8) 1 : City of Belpre,OH 2,831 71 .6 45 .2 17 .6 134 .9 2 : Tupper Plains 4,807 63 .0 48 .9 18 .5 111 .7 3 : Little Hocking Water Association 4,338 396 .9 290 .0 83 .6 820 .5 4 : Lubeck Public Service District 5,494 131 .7 90 .4 30 .9 237 .0 5 : Mason County 3,522 19 .1 6 : Village of Pomeroy 734 18 .6 Other 8,903 82 .6 15 .5 7 .4 34 .2 15 .6 7 .1 32 .6 29 .1 91 138 .3 Total 30,629 123 .0 47 .8 11 .7 284 .9 Table 3 .3 Mean, median and range within some percentile fractions (Unit s ug/1) . N mean(c8) med (c8) min max Lowest 3,117 8 . 10 % 8 .5 .25 11 . Uppei 3,063 664 . 479 285 11391 .9 10% ' Lower 15,323 22 . 21 .2 50% .25 47 .8 Upper 15,306 223 .2 113 47 .9 11391 .9 50% p. 4 TSCA Document Processing Center August 10, 2006 Attn: Section 8(e)/FYI Page 8 of 10 Figure 3 .1 Distribution of log c8 in bloo d ~ . . ,. 3 .3 Power Power is presented in Table 3 .4 as the chance of being able to detect a significant result for a modest increase in RR (1 .25) and a substantial increase in RR 2 .0 for the simplest comparison between the upper and lower half of the population (with C8 in blood, mean 223 ug/l and 23 ug/l respectively). [With alpha 0 .05, two sided . Calculated with 'sampsize' in STATA.] Note that this may underestimate power relative to analyses that consider the full range of exposure or ordered categories, but ignores more complex models with multiple covariates which can reduce power somewhat . Nonetheless, these estimates convey a good sense of the magnitudes of association we will be capable of detecting . Table 3 .4 summary of power calculations % Power to detect RR of: Expected n 1 .25 2 .0 Bladder 106 18 92 Breast (fem) 559 75 10 0 Kidney 113 19 93 Testes 59 11 68  p . 5 TSCA Document Processing Center August 10, 2006 Attn : Section 8(e)/FYI Page 9 of 10 The Science Panel also reports the following with respect to a trend observed in the C-8 blood levels: 3 The C8 health project data and trends in PFOA levels in the study area [The Science Panel has] a very detailed source of good quality data on C8 levels at an individual level by virtue of the large amount of data collected by the Brookmar team. This will be supplemented by a detailed assessment of the patterns of metabolism and clearance of C8 in the half life study component . This data have been assembled over nearly a year and an initial examination of it reveals a significant trend in C8 by community, which has implications for the design of our study . He following figure shows the pattern of C8 levels for people classified by the current water district in which they live (after excluding those who live outside the catchment area of the 6 water districts) . Each point is the average of a weeks' collection of blood samples over 47 weeks of data collection. In each water district they appear to have a downward slope . 1 2 3 ? ~~. .~:~w"~~%o^~ 4 :/.~/+rwr:...w.r.: 5 +wS r ~w i 8 C~ 50 l 50 Idetew 0 f imean> c8 Fitted valws Craphs hy l water <ource as-is pune_ select Istnct 50 The trends are more readily seen in the log-transformed C8 data : the following graphs illustrate the similar proportional trend in average weekly mean log c8 within each of the six water districts :  p. 6 TSCA Document Processing Center Attn: Section 8(e)/FYI August 10, 2006 Page 10 of 10 ~ -- ,--.--_~ ~._~-_--._-._.-. -. . .- ~z_~.~ .. ~~, . .~ .~ .,,~_ ~ ~, . . .--.+- .~ . . ~ : .. _ `~ . .~ . a qr ~t . z= to to . _ ~ 1~ ' . ~ ~ ~ r, . t ~ ~ ! w ' ~ .~ ' .! . 0 10 20 ~ bpcB_t bqd_: Fa .E vMns - Fil.d .a~rs byct 1 qy~Y. --T- ~T 30 40 50 Idatwv fn .dx.Wi FNOrWn "A-5 1 IWA-6 F/1.l .7Y.l F/.. .4kM4 The magnitude of the slope is about a 7% drop per month : If the within-individual trend is comparable to the observed slope for the community (i .e . the observed slope is not due to a downward trend in the proportion of individuals who happen to have relatively high C8 in blood unlikely to have been repeated in each water district) then this would indicate a rather steep decline : the combination of reducing intake and clearance would then appear to be associated with a half life of less than a year . At this rate the c8 level in the blood has fallen by nearly 60% in a year .