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Environmental Checklist and City of Pleasanton–10x Genomics Project <br />Environmental Evaluation Initial Study/Mitigated Negative Declaration <br /> <br /> <br />40 FirstCarbon Solutions <br />Https://adecinnovations.sharepoint.com/sites/PublicationsSite/Shared Documents/Publications/Client (PN-JN)/2148/21480024/ISMND/wp/21480024 10x Genomics Project Full Screencheck ISMND.docx <br />Estimation of Cancer Risks <br />The BAAQMD has developed a set of guidelines for estimating cancer risks that provide adjustment <br />factors that emphasize the increased sensitivities and susceptibility of young children to exposures <br />to TACs.24,25 These adjustment factors include age-sensitivity weighting factors, age-specific daily <br />breathing rates, and age-specific time-at-home factors. The recommended method for the <br />estimation of cancer risk is shown in the equations below with the cancer risk adjustment factors <br />provided in Table 7 for several types of sensitive/residential receptors (infant, child, and adult). <br />Cancer Risk = CPF x DOSEAIR x ASP x ED/AT x FAH (EQ-1) <br />Where: <br />Cancer Risk = Total individual excess cancer risk defined as the cancer risk a hypothetical <br />individual faces if exposed to carcinogenic emissions from a particular source for specified <br />exposure durations; this risk is defined as an excess risk because it is above and beyond the <br />background cancer risk to the population; cancer risk is expressed in terms of risk per million <br />exposed individuals. <br />CPF = Inhalation Cancer Potency Factor (1.1) <br />ASF = Age Sensitivity Factor (see Table 7) <br />ED = Exposure Duration (BAAQMD recommends 3 years for short-term projects less than 3 <br />years in duration) <br />AT = Averaging Time for lifetime cancer risk (70 years) <br />FAH = Fraction of time At Home <br />DOSEAIR = CAIR x DBR x A x EF (EQ-2) <br />Where: <br />CAIR = TAC concentration from air dispersion model (µg/m3) <br />DBR = Daily Breathing Rate (BAAQMD recommends 95th percentile for residential receptors; <br />liter of air per kilogram of body weight per day) <br />A = Inhalation Absorption factor (1) <br />EF = Exposure Frequency (workdays/365 days) <br />The California Office of Environmental Health Hazard Assessment (OEHHA) recommended values for <br />the various cancer risk parameters, as described by equations 1 and 2 above (EQ-1 and EQ-2), are <br />provided in Table 7. <br /> <br />24 Bay Area Air Quality Management District (BAAQMD). 2017. California Environmental Quality Act Air Quality Guidelines. May. <br />Website: https://www.baaqmd.gov/~/media/files/planning-and research/ceqa/ceqa_guidelines_may2017-pdf.pdf?la=en. Accessed <br />June 8, 2020. <br />25 Bay Area Air Quality Management District (BAAQMD). 2020. BAAQMD Health Risk Assessment Modeling Protocol. August. Website: <br />https://www.baaqmd.gov/~/media/files/ab617-community-health/facility-risk- <br />reduction/documents/baaqmd_hra_modeling_protocol_august_2020-pdf.pdf?la=en. Accessed January 6, 2020.