Laserfiche WebLink
L <br /> Health Risk Assessment <br /> bw <br /> The SJVUAPCD has a significance threshold for health risk exposure to diesel emissions of 10 <br /> cancers per million for 70-year exposure; indicating the primary concern from diesel engine. <br /> exhaust emissions is a potential long-term health risk to sensitive receptors. <br /> CANCER RISKS <br /> The cancer risks from DPM occur exclusively through the inhalation pathway;therefore the <br /> cancer risks can be estimated from the following equation: <br /> CRDPM =CDPM •URFDPM •LEA <br /> Ys <br /> where, <br /> CRDPM Cancer risk from DPM;the probability of an individual developing cancer as <br /> a result of exposure to DPM. <br /> r1 CDPM Annual average DPM concentration in µg/m3. <br /> URFDPM Unit risk factor for DPM;estimated probability that a person will contract <br /> y^ cancer as a result of inhalation of a DPM concentration of 1 µg/m' <br /> continuously over a period pf 70 years. <br /> ~ LEA Lifetime exposure adjustment; values range from 0.14 to 1.0. <br /> LThe inhalation unit risk factor for diesel particulate was established by CARB as 300 in one <br /> million per continuous exposure of I µg/m3 of DPM over a 70-year period. In order to protect <br /> public health, and in accordance with the recommendations of the State of California Office of <br /> L Environmental Health Hazard Assessment (OEHHA), a 70-year lifetime exposure is assumed for <br /> receptor locations. The LEA for most residential or sensitive receptors is 1.0. However, <br /> exposure adjustments can be made based on the exposure duration (ex., schools and industrial <br /> workers). <br /> 6a NON-CANCER RISKS <br /> The relationship for the non-cancer health effects of DPM is given by the following equation: <br /> HIDPM=CDPM/RELDPM <br /> L where, <br /> HIDPM Hazard Index; an expression of the potential for non-cancer health effects. <br /> t. <br /> Ir <br />