Assessment of Human Exposure to Traditional and Novel Organophosphate Esters via Multiple Personal Matrices.

Herein, 16 traditional and 13 novel organophosphate esters (OPEs) in skin wipes, personal PM2.5, sputum, and nails (fingernails and toenails) and 7 OPE metabolites in urine synchronously obtained from 64 college students were analyzed. Similar compositional profiles of the OPEs were found in skin wipes and nails and in personal PM2.5 and induced sputum. Significant correlations were observed between the concentrations of high-lipophilicity low-volatility OPEs in skin wipes and nails and between the concentrations of high-volatility low-lipophilicity OPEs in personal PM2.5 and sputum. These results imply that OPEs in fingernails and toenails may mainly come from external sources rather than internal exposure, and human nails and sputum can be used as indicators of human exposure to OPEs. A comparison between the daily exposure doses of the OPEs in personal PM2.5 and sputum shows that more volatile compounds may have higher inhalation bioavailability, which should be considered to improve the accuracy of inhalation exposure assessments. According to comprehensive external and internal exposure assessment, dermal absorption may be a more dominant pathway than inhalation, and skin wipes may be the best representative environmental matrix of human exposure to OPEs.

Face mask as an indicator and shield of human exposure to traditional and novel organophosphate esters.

Herein, the trapping effectiveness of N95, filter KN95, medical surgical masks (MSMs), and disposable medical masks (DMMs) against 19 airborne traditional and novel organophosphate esters (OPEs) was evaluated. Laboratory simulations (n = 24 for each type of mask) showed that time-dependent accumulation of ∑19OPEs on the four types of masks ranged between 30.1 and 86.6 ng in 24 h, with the highest and lowest median amounts trapped by the N95 masks (53.3 ng) and DMMs (43.2 ng), respectively. The trapping efficiency of the four types of masks for ∑19OPEs decreased over time from 84 % to 39 % in 24 h, with N95 masks showing the highest median efficiency (70 %). Further, field investigations were conducted in five types of microenvironments (train, hospital, bus, supermarket, and canteen), and an analysis of 200 samples showed that ∑19OPEs were accumulated in the masks with a variable amount from 3.7 to 117 ng/mask. Consistent with the laboratory simulations, the N95 masks (29.0 ng/mask) exhibited the highest hourly median amount of trapped OPEs, followed by the KN95 masks (24.5 ng/mask), MSMSs (17.4 ng/mask), and DMMs (15.8 ng/mask). Triethyl phosphate (TEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tri-n-butyl phosphate (TNBP), and cresyl diphenyl phosphate (CDP) as well as 4-isopropylphenyl diphenyl phosphate (4IPPDPP) and 2,4-diisopropylphenyl diphenyl phosphate (24DIPPDPP) were the most commonly detected traditional and novel OPEs. Based on the amount of OPEs trapped on the masks, we estimated the concentration of ∑19OPEs in the train microenvironment to be the highest (222 ng/m3), which is approximately 2-5 times higher than that in the other microenvironments. The results of this study prove that masks can effectively protect humans from exposure to OPEs and act as low-cost indicators of indoor contamination.

Characteristics of airborne particles retained on conifer needles across China in winter and preliminary evaluation of the capacity of trees in haze mitigation.

To fully understand the characteristics of particulate matter (PM) retained on plant leaves (PMR) and the effect of vegetation on haze on a large spatial scale, we investigated needle samples collected from 78 parks and campuses in 31 cities (30 provincial cities) of China and developed a comprehensive method to characterise PMR. Both the PMR load (including water-insoluble particulate matter (WIPM), water-soluble inorganic ions (WSIS) and water-soluble organic matter (WSOM)), with a mean value of 554 ± 345 mg m-2 leaf area, and component profiles of PMR showed obvious spatial variation across the cities. Though haze pollution levels vary greatly among the 31 cities, the PM retention capacity of needles does not depend on haze level because PMR generally reaches saturation before precipitation in winter. The water-soluble component (WSC, the sum of WSIS and WSOM) accounted for 52.3% of PMR on average, among which WSIS and WSOM contributed 21.4% and 30.9% to PMR, respectively. The dominant ions of WSIS in PMR in the cities were Ca2+, K+ and NO3-, indicating that raised dust, biomass combustion and traffic exhaust are significant sources of PM in China. Compared with previous reports, the particle size distributions of PMR and PM across China were consistent, with fine PM (PM2.5) constituting a substantial proportion (43.8 ± 17.0%) of PMR. These results prove that trees can effectively remove fine particles from the air, thereby reducing human exposure to inhalable PM. We proposed a method to estimate the annual amount of PMR on Cedrus deodara, with an average value of 11.9 ± 9.6 t km-2 canopy yr-1 in China. Compared with the load of dust fall (atmospheric particles naturally falling on the ground, average of 138 ± 164 t km-2 land area yr-1 in China), we conclude that trees play a significant role in mitigating haze pollution.

Impact of Formal Care Use on Informal Care from Children after the Launch of Long-Term Care Insurance in Shanghai, China.

The impact of formal care (co-paid by long term care (LTC) insurance) on informal care is critical to the improvement and promotion of public policy. We conducted an interview-based survey to examine how the use of formal care impacts the use of informal care in Shanghai, which was one of China's first long-term insurance pilots in 2016. In addition to total informal care time, the following four types of informal care were considered: (1) household activities of daily living (HDL) tasks, (2) activities of daily living (ADL) tasks, (3) instrumental activities of daily living (IADL) tasks, and (4) supervision tasks. Of the 407 families, an average of 12.36 h (SD = 6.70) of informal care was crowded out each week. Among them, ADL tasks, HDL tasks, and supervision tasks were reduced an average of 4.60 (SD = 3.59), 5.50 (SD = 3.38), and 2.10 h (SD = 3.06) per week, respectively. Each additional hour of formal care reduced 0.473 h of informal care. Care recipients' gender and health status were also determined to be associated with crowding out hours of informal care. These findings can be utilized as empirical evidence for decision-makers to consider the scope of funding for formal care, and this study provides comparable results to developing countries and regions.

Size-distribution-based assessment of human inhalation and dermal exposure to airborne parent, oxygenated and chlorinated PAHs during a regional heavy haze episode.

The adverse health effects of haze and particle-bound contaminants in China have recently caused increasing concern, and particle size plays a significant role in affecting human exposure to haze-correlated pollutants. To this background, size-segregated particulate samples (nine size fractions (<0.4, 0.4-0.7, 0.7-1.1, 1.1-2.1, 2.1-3.3, 3.3-4.7, 4.7-5.8, 5.8-9.0 and > 9.0 µm) were collected in three scale-gradient cities in northern China and analysed for a series of parent, oxygenated and chlorinated polycyclic aromatic hydrocarbons (PAHs, O-PAHs and Cl-PAHs). The total geometric mean concentrations of PAHs and O-PAHs for Beijing, Zhengzhou and Xinxiang were 98.1 and 27.2, 77.9 and 77.5, 41.0 and 30.7 ng m-3, respectively, which were 50-200 times higher than those for Cl-PAHs (0.5, 0.7 and 0.4 ng m-3). Though unimodal size-distribution patterns were found for all these contaminants for these three cities, PAHs represented distinctly higher concentration levels around the peak fraction (0.7-2.1 µm) than O-PAHs and Cl-PAHs. With 4-6 ring PAHs as dominant components in all samples, the percentage proportion of 2-3 ring PAHs (ranging from 1% to 26%) generally increased with particle size increasing, implying the sources of these compounds varied little among the 9 size fractions in all three cities. The International Commission on Radiological Protection (ICRP) model and permeability coefficient method were synchronously applied to the size-segregated data for inhalation and dermal exposure assessment to intensively estimate the human exposure doses to airborne PAHs. Further, the incremental lifetime cancer risk (ILCR) was calculated and it's found that ILCR from inhalation was higher than that from dermal uptake for children and adults in Beijing and Zhengzhou, while the ILCR for Xinxiang presented a contrary pattern, revealing dermal uptake to be an equally significant exposure pathway to airborne PAHs compared to inhalation.

Higher health risk resulted from dermal exposure to PCBs than HFRs and the influence of haze.

To investigate the influence of haze on human dermal exposure to a series of halogenated flame retardants (HFRs) and polychlorinated biphenyls (PCBs), paired forehead wipes were collected from 46 volunteers (23 males, 23 females) using gauze pads soaked in isopropyl alcohol under heavy and light haze pollution levels. The median levels of ∑27HFRs and ∑27PCBs in all 92 samples were 672 and 1300ng/m2, respectively. Decabromodiphenyl ether (BDE-209) (171ng/m2) and decabromodiphenylethane (DBDPE) (134ng/m2) were the dominant components of HFRs, indicating that dermal exposure may also be the significant pathway for non-volatile compounds. PCB-37 contributed the most to ∑27PCBs, with a median concentration of 194ng/m2, followed by PCB-60 (141ng/m2). Generally, PBDE, PCB and DD (dehalogenated derivatives of DPs) levels on the foreheads of female participants (291, 1340, 0.92ng/m2) were higher (p=0.037, 0.001, and 0.031, respectively) than those of male participants (226, 989, and 0.45ng/m2). A significant difference (p=0.001) in PCBs was found between light (1690ng/m2) and heavy (996ng/m2) haze pollution conditions. Nevertheless, HFR levels under heavy (median=595ng/m2, ranging from 295 to 1490ng/m2) and light haze pollution conditions (ranging from 205 to 1220ng/m2 with a median of 689ng/m2) did not show significant differences (p=0.269). The non-carcinogenic health risk resulting from dermal exposure to ∑8HFRs and ∑27PCBs was 8.72×10-5 and 1.63×10-2, respectively, raising more concern about populations' exposure to PCBs than HFRs.