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To determine the priority control sources, an approach was proposed to evaluate the source-specific contribution to health risks from inhaling PM 2.5 -bound heavy metals (PBHMs). A total of 482 daily PM 2.5 samples were collected from urban and suburban areas of Beijing, China, between 2018 and 2019. In addition to the PMF-PSCF model, a Pb isotopic IsoSource model was built for more reliable source apportionment. By using the comprehensive indicator of disability-adjusted life years (DALYs), carcinogenic and noncarcinogenic health risks could be compared on a unified scale. The study found that the annual average concentrations of the total PBHMs were significantly higher in suburban areas than in urban areas, with significantly higher concentrations during the heating season than during the nonheating season. Comprehensive dust accounted for the largest contribution to the concentration of PBHMs, while coal combustion contributed the most to the DALYs associated with PBHMs. These results suggest that prioritizing the control of coal combustion could effectively reduce the disease burden associated with PBHMs, leading to notable public health benefits. • Most PBHMs have higher concentrations in Beijing suburban areas than in urban areas. • The PMF-PSCF-IsoSource model can reduce the uncertainty in source apportionment. • Coal and fuel oil combustion should be controlled with a priority for public health. • The disease burden of noncarcinogenic effects must not be overlooked. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are the main toxic components bound to PM 2.5 that have carcinogenic, teratogenic and mutagenic toxicity. Priority control sources were determined by integrating source apportionment with a comparative health risk index of disability adjusted life years (DALYs). The positive matrix factorization (PMF) method was applied to 255 daily PM 2.5 -bound PAH concentrations detected during 2017 in urban Beijing. Three sources and mass contributions were determined: vehicle emissions (62.6%); coal and natural gas combustion and petroleum volatilization (29.5%); and biomass combustion (8.0%). The conditional probability function (CPF) analysis of the three sources revealed that the near-distance potential source direction was southeast of Beijing. The higher ratio of (3 + 4) ring PAHs/(5 + 6) ring PAHs in the summer implied a longer transport distance of PAHs and a larger emission region for the summer than for the other three seasons. The source-attributed DALYs were estimated based on the source mass contribution from PMF, the inhalation unit risk of PAHs for each disease and the individual DALYs for each disease. The total burden of some typical diseases attributable to PM 2.5 -bound PAHs was 923.44 DALYs/year, or 6.82 × 10−5 DALYs/person/year. Among these diseases, the carcinogenic effect imposed the greatest burden, accounting for 99.6% of the total burden of disease (upper respiratory cancer accounted for 16.0% and tracheal, bronchial and lung cancer accounted for 83.6%). Although the order of sources by disease burden was identical to that by mass contribution, vehicle emissions contributed a much larger disease burden (79.7%) and thus should be reduced further. The DALYs index breaks the barrier between noncarcinogenic and carcinogenic risk assessments. This enables comparison of the disease burden among different regions and pollutants and is thus helpful for source control and risk management. Image 1 • DALYs and PMF were combined to quantify the PAH source-attributed disease burden. • More systemic toxic effects were considered in addition to critical effects. • Morbidity was estimated from PAH exposure and the unit risk of diseases. • Vehicle emissions were the highest contributor to DALYs due to PM 2.5 -bound PAHs. [ABSTRACT FROM AUTHOR]

PM 2.5 -bound toxic metals (TMs) are derived from various sources, and they can cause many adverse health effects on the human body. To effectively reduce the disease burden of TMs by controlling the relative sources, an integrated approach of quality-adjusted life years (QALYs) and source-apportionment (positive matrix factorization, PMF) was proposed and applied to some typical diseases induced by TMs in 2017 in Beijing. The estimation included two parts; first, the number of potentially affected people was calculated based on the source mass contribution from PMF and the inhalation unit risk of TMs; second, the QALYs lost per affected person was calculated based on the disease duration, expected years of life lost (EYLL) and quality of life (QoL) for both affected people and the general population. The results showed that QALYs lost per person for renal cancer (17.3 QALYs), pneumonia (14.4 QALYs), lung cancer (14.2 QALYs), skin cancer (12.7 QALYs) and diabetes mellitus (12.6 QALYs) were higher than those for other diseases. Combined with PMF, the source contributions to the overall burden of typical diseases from the TMs followed the order of coal combustion (50.2%) > vehicle emissions (24.4%) > fuel oil combustion (11.4%) > Cr-related industry (10.9%) > resuspended dust (3.0%). The rank was further compared with that assessed for noncancer and cancer risks, and we verified the reasonability of the QALYs method. For seasonal contributions to coal combustion, winter and spring had the highest contributions, which coincided with the fact that coal was the main fuel for heating in Beijing. The QALYs lost attributed to TMs for coal combustion decreased by 49.1% from 2016 to 2017, which may indicate an effective policy associated with coal control. Overall, the integrated approach was successfully employed for estimating the disease burden induced by TMs from each source and was an effective solution to identify the control rank of sources for TM reduction. Unlabelled Image • QALYs and PMF were integrated to quantify the source-attributed disease burden for TMs. • A model of calculating the QALYs lost per person for typical diseases was built. • The ranks of source-attributed QALYs lost from PM 2.5 -bound TMs were clarified. • Coal burning contribution to the QALYs lost to TMs was the highest but sharply decreased. • More pollutants/toxic effects should be included to determine priority source control. [ABSTRACT FROM AUTHOR]