Combustion-Derived Pollutants Linked with Kidney Disease in Low-Lying Flood-Affected Areas in the Balkans.

Tens of thousands of people in southern Europe suffer from Balkan endemic nephropathy (BEN), and four times as many are at risk. Incidental ingestion of aristolochic acids (AAs), stemming from the ubiquitousAristolochia clematitis(birthwort) weed in the region, leads to DNA adduct-induced toxicity in kidney cells, the primary cause of BEN. Numerous cofactors, including toxic organics and metals, have been investigated, but all have shown small contributions to the overall BEN relative to non-BEN village distribution gradients. Here, we reveal that combustion-derived pollutants from wood and coal burning in Serbia also contaminate arable soil and test as plausible causative factors of BEN. Using a GC-MS screening method, biomass-burning-derived furfural and coal-burning-derived medium-chain alkanes were detected in soil samples from BEN endemic areas levels at up to 63-times and 14-times higher, respectively, than in nonendemic areas. Significantly higher amounts were also detected in colocated wheat grains. Coexposure studies with cultured kidney cells showed that these pollutants enhance DNA adduct formation by AA, - the cause of AA nephrotoxicity and carcinogenicity. With the coincidence of birthwort-derived AAs and the widespread practice of biomass and coal burning for household cooking and heating purposes and agricultural burning in rural low-lying flood-affected areas in the Balkans, these results implicate combustion-derived pollutants in promoting the development of BEN.

Face Mask as a Versatile Sampling Device for the Assessment of Personal Exposure to 54 Toxic Compounds in Environmental Tobacco Smoke.

Exposure to environmental tobacco smoke (ETS), which contains hundreds of toxic compounds, significantly increases the risk of developing many human diseases, including lung cancer. The most common method of assessing personal exposure to ETS-borne toxicants is by sampling sidestream smoke generated by a smoking machine through a sorbent tube or filter, followed by solvent extraction and instrumental analysis. However, the ETS sampled may not truly represent the ETS in the ambient environment, due to complicating factors from the smoke released by the burning end of the cigarette and from the absorption of the chemicals in the respiratory tract of the smoker. In this study, we developed and validated an alternative air sampling method involving breathing through a face mask to simultaneously determine personal exposure to 54 ETS-borne compounds, including polycyclic aromatic hydrocarbons, aromatic amines, alkaloids, and phenolic compounds in real smoking scenarios. The newly developed method was used to evaluate the risk associated with exposure to ETS released from conventional cigarettes (CCs) and that from novel tobacco products such as e-cigarettes (ECs) and heated tobacco products (HTPs), with the observation of cancer risk associated with exposure to ETS released from CCs significantly higher than that from ECs and HTPs. It is anticipated that this method offers a convenient and sensitive way to collect samples for assessing the health impacts of ETS exposure.

Highly time-resolved measurements of elements in PM2.5 in Changzhou, China: Temporal variation, source identification and health risks.

The temporal variation, sources, and health risks of elemental composition in fine particles (PM2.5) were explored using online measurements of 19 elements with a time resolution of 1 h at an urban location in Changzhou, China, from December 10, 2020 to March 31, 2021. The mass concentration of PM2.5 was 50.1 ±â€¯32.6 µg m-3, with a range of 3-218 µg m-3. The total concentration of 19 elements (2568 ±â€¯1839 ng m-3) accounted for 5.1 % of PM2.5 mass concentration. S, Cl, Si, and Fe were the dominant elementary species, accounting for 90 % of total element mass concentrations during the whole campaign. Positive matrix factorization (PMF) model was applied to identify the major emission sources of elements in PM2.5. Seven factors, named secondary sulfate mixed with coal combustion, Cl-rich, traffic, iron and steel industry, soil dust, fireworks, and shipping, were identified. The major sources for elements were iron and steel industry, followed by soil dust and secondary sulfate mixed with coal combustion, explaining 32.0 %, 23.5 % and 16.7 % of the total source contribution, respectively. The total hazard index (HI) of elements was 3.01 for children and 1.18 for adults, much greater than the admissible level (HI = 1). The total carcinogenic risk (CR) in Changzhou was estimated to be 5.87 × 10-5, which was above the acceptable CR level (1 × 10-6). Among the calculated metal elements, Cr, Co and As have higher carcinogenic risk, and Co was found to trigger the highest noncarcinogenic risk to Children. Our results indicate that industrial emission is the dominant CR contributor, emphasizing the necessity for stringent regulation of industry sources. Overall, our study provides useful information for policymakers to reduce emissions and health risks from elements in the Yangtze River Delta region.

Polyurethane Foam Face Masks as a Dosimeter for Quantifying Personal Exposure to Airborne Volatile and Semi-Volatile Organic Compounds.

Airborne volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) are commonly quantitated by collecting the analytes on solid sorbent tubes or passive air samplers, followed by solvent extraction and instrumental analysis, or by grab bag/canister measurements. We report herein a user-friendly sampling method by breathing through polyurethane foam (PUF) face masks to collect airborne VOCs and SVOCs for chemical analysis. Specifically, dibasic esters, phthalate esters, polycyclic aromatic hydrocarbons, linalool, and nicotine trapped on PUF masks were quantitated by gas chromatography-mass spectrometry analysis as model VOCs and SVOCs. Results showed that the amount of these model VOCs and SVOCs trapped on PUF masks is proportional to the exposure duration. After cross-validation by parallel sampling using XAD-2 packed sorbent tubes, the method was used to quantitate VOCs and SVOCs in a variety of indoor and outdoor environments with varying air concentrations of analytes, temperature, humidity, and wind speed. Because air pollution is considered a major cause of many human diseases and premature deaths and the developed PUF mask sampling method showed high trapping efficiencies for both VOCs and SVOCs, it is believed that the developed sampling method will find wide application in assessing air pollution-associated disease risks with possible extension to more classes of VOCs and SVOCs when coupled with suitable instrumental detection methods.

Polyurethane-Based Face Mask as a Sampling Device for Environmental Tobacco Smoke.

Environmental tobacco smoke (ETS), also known as secondhand smoking, contains human carcinogens associated with the development of many human diseases, including stroke, heart disease, leukemia, and lung cancer. Due to these adverse health effects, a sensitive and selective method is crucial for assessing the health impacts of ETS. While current methods to evaluate ETS exposure are either invasive or nonspecific and insensitive, in this study, we assessed the use of polyurethane foam face masks as a sampling medium to collect tobacco smoke-specific nicotine and nitrosamines for estimating personal exposure to ETS. This method was used in conjunction with tandem mass spectrometry coupled with isotope-dilution detection. After validation by comparison with the National Institute for Occupational Safety and Health standard method (NIOSH 2551) for nicotine, we quantitated ETS exposure in indoor and outdoor environments. The analysis shows the applicability of the method for monitoring nicotine down to ∼0.20 mg/m3 near an outdoor smoking hotspot and up to ∼5.2 mg/m3 in a room with burning cigarettes, all with a time resolution as short as 5 min. In comparison with the NIOSH method, the newly developed method is convenient, inexpensive, and does not require a personal sampling pump, thus can facilitate large-scale ETS exposure monitoring.

Estimating primary vehicular emission contributions to PM2.5 using the Chemical Mass Balance model: Accounting for gas-particle partitioning of organic aerosols and oxidation degradation of hopanes.

Particulate matter emitted from vehicles (PMvehicle) represents a major air pollution source in urban areas. Ambient measurements of hopanes and elemental carbon have traditionally been coupled with the Chemical Mass Balance (CMB) model to quantify the contributions to fine PM from diesel and gasoline vehicular emissions (VE). The organic carbon part of PMvehicle, however, undergoes gas-particle partitioning and oxidation degradation as VE move from exhaust pipe to receptor sites. This creates an issue of deviation from mass conservation in the utility of CMB. The impact of this issue on quantifying PMvehicle has remained largely uncharacterized. In this study, we incorporate in CMB the gas-particle partitioning of VE organic aerosols and hopane oxidation, which is equivalent to adopting dynamic VE source profiles. The modified version of CMB is applied to quantify primary PMvehicle contributions at a roadside and a general urban site in Hong Kong. For the roadside site, the modified CMB reports predominant PMvehicle by diesel VE, a result consistent with previous studies. For the general urban site, the apportioned gasoline contribution by the modified CMB is tripled (0.8 ± 0.5 vs. 2.7 ± 2.1 µg/m3) while the diesel contribution is reduced by one third (1.7 ± 1.2 vs. 1.1 ± 1.2 µg/m3), producing a gasoline-diesel split significantly different from that by traditional CMB (1:2 vs. 5:2). Our work strongly indicates that a static representation of VE source profiles in CMB modeling would create flawed PMvehicle estimation and demonstrates the necessity of considering gas-particle partitioning of organic aerosol and hopane oxidation degradation.

Hourly measurement of PM2.5-bound nonpolar organic compounds in Shanghai: Characteristics, sources and health risk assessment.

Fine particulate matter (PM2.5)-bound nonpolar organic compounds (NPOCs), including polycyclic aromatic hydrocarbons (PAHs) and alkanes, are commonly used as typical molecular markers for detailed source identification. Online thermal desorption aerosol gas chromatography-mass spectrometry (TAG) system can obtain ambient data with hourly resolution, which is of great importance for investigating the diurnal characteristics and refined source identification of NPOCs. From June to October 2020, hourly ambient aerosol samples were collected and analyzed to investigate the characteristics and sources of 14 PAHs and 15 alkanes (C21-C35) in PM2.5 using TAG at a suburban site of Baoshan district in Shanghai, China. The average concentration of summed PAHs and alkanes during the sampling period was 1.27 ± 1.4 ng/m3 and 8.87 ± 3.46 ng/m3, respectively, in which Benzo[b]fluoranthene (BbF), Benzo[ghi]perylene (BghiP) and Indeno[1,2,3-cd]pyrene (IcdP) are the dominant PAHs species, with n-Heptacosane (C27), n-Nonacosane (C29) and n-Hentriacontane (C31) being the most abundant n-alkane species. Carbon preference index (CPI) and carbon maximum (Cmax) number indicated that the sources of alkanes shifted from biogenic-oriented (such as plant wax) in the summer to anthropogenic-dominated (such as fossil fuels) in the autumn. Results from trajectory cluster analysis and potential source contribution function (PSCF) modeling showed that alkanes were mainly from the middle and lower reaches of the Yangtze River Plain including Anhui, Jiangxi, and Zhejiang provinces, while PAHs were mainly from northeastern China. Positive Matrix Factorization (PMF) model results indicated that gasoline (41.48%) and diesel (21.82%) were the two major sources of PM2.5-bound PAHs in summer and fall of 2020 in Shanghai, followed by coal consumption or catering (19.96%) and biomass burning (16.74%). Diurnal variation of PAHs sources resolved by PMF showed characteristic features consistent with the corresponding anthropogenic activities. For example, gasoline vehicle exhaust showed higher concentrations during traffic rush hours; while coal consumption or catering presented higher concentrations during lunch times from 10:00 to 12:00. In addition, the TAG data coupling with PMF also can be capable for source appointment of short-duration episodes. Health risk assessment showed that adult women were at greater lifetime cancer risk (ILCR) than people in other age groups, and people may subject to higher health risks at morning and night time. This work demonstrates that hourly NPOCs measured by TAG are uniquely specific on refined source identification and investigation into the characteristics of diurnal variations.

Characteristics and health impacts of VOCs and carbonyls associated with residential cooking activities in Hong Kong.

Cooking emission samples collected in two residential kitchens were compared where towngas (denoted as dwelling A) and liquefied petroleum gas (LPG) (denoted as dwelling B) were used as cooking fuels. A total of 50 different volatile organic compounds (VOCs) were quantified during the 90 min cooking periods. None of any carcinogenic compounds like formaldehyde, acetaldehyde or benzene are detected in the raw fuels, confirming that those are almost entirely derived due to cooking activity alone. Alkenes accounted for approximately 53% of the total measured VOCs collected at dwelling A, while alkanes contributed approximately 95% of the VOCs at dwelling B during the cooking periods. The concentration of aromatic hydrocarbons such as benzene and toluene also increased during the cooking periods. The total amount of carbonyls emitted from the cooking processes at dwelling A (2708 µg) is three times higher than that at dwelling B (793 µg). Acetaldehyde was the most abundant carbonyl at the dwelling A but its emission was insignificant at the dwelling B. Carcinogenic risks on chronic exposure to formaldehyde, acetaldehyde, and benzene for housewives and domestic helpers were evaluated. Formaldehyde accounts for 68% and close to 100% of lifetime cancer risks at dwelling A and B, respectively.

Determination of gaseous carbonyl compounds by their pentafluorophenyl hydrazones with gas chromatography/mass spectrometry.

A sensitive and reliable method has been developed for the simultaneous determination of 20 airborne carbonyl compounds in the C(1)-C(10) range. The carbonyls were collected onto solid sorbent coated with pentafluorophenyl hydrazine (PFPH), followed by solvent extraction and gas chromatographic (GC)/mass spectrometric (MS) analysis of the PFPH derivatives. The sorbent is packed into two separate sections in a glass sampling tube. The two-section design allows convenient checking of collection efficiency and breakthrough. The sampling tube, with a coating amount of 971 nmol PFPH per 100 mg Tenax TA and operated at a sampling flow rate of 80 mL min(-1), collects the 20 carbonyls with efficiencies above 95%. Hexane extracts the collected carbonyls in their PFPH derivatives in the sampling tube with better than 95% extraction efficiency. It is necessary to let the sampling tube sit at ambient temperature for 3 days before solvent extraction to ensure complete derivatization of the carbonyls. The limits of detection (LODs) of the tested carbonyls are in the range of 3.7-11.6 ng per sample. The method has been field-tested both in ambient environment and in an indoor environment from burning mosquito-repellent incense. Eighteen carbonyls were detected in the ambient air samples with the exception of o-tolualdehyde and m-tolualdehyde, while all the 20 target carbonyls were found in the incense smoke. Compare field test with classical DNPH-HPLC/UV method, good agreement exited between the two methods for lower molecular carbonyls but PFPH method is found to be a better analytical method for determination of high molecular weight carbonyls.

Evaluation of an in-injection port thermal desorption-gas chromatography/mass spectrometry method for analysis of non-polar organic compounds in ambient aerosol samples.

Thermal desorption coupled with gas chromatography/mass spectrometry (TD-GC/MS) is an alternative to solvent extraction (SE)-based GC/MS (SE-GC/MS) for the analysis of non-polar organic compounds in filter or impactor-collected aerosols. TD-GC/MS has no sample pretreatment and requires a small filter aliquot for detecting individual organic compounds. The performance of an in-injection port TD-GC/MS is evaluated for polycyclic aromatic hydrocarbons (PAHs), n-alkanes, iso-/anteiso-alkanes, hopanes, steranes, branched alkanes, cyclohexanes, alkenes, and phthalates in standards and ambient air samples. Replicate analysis for 132 organic compounds showed relative standard deviations <10%, with the majority <5%. Accuracy for 15 PAHs, determined with NIST standard reference material (SRM) 1649a urban dust, was within +/-5% of the certified values. TD-GC/MS and SE-GC/MS method comparisons for 14 Hong Kong ambient samples agreed within 11% for 106 non-polar compounds. For 19 Tong Liang, China samples, agreement was within 13% for 23 PAHs.

Determination of trace amounts of formaldehyde in acetone.

A method to quantify sub-ppm levels of formaldehyde in acetone has been developed and it is reported here. In this method, the different reactivities and stabilities of sulfite with formaldehyde and acetone are used to separate the two carbonyl compounds. Sulfite reacts with formaldehyde to form hydroxymethanesulfonate (HMS), the non-volatile and stable nature of which allows its separation from bulk acetone solvent. The resulting HMS is then converted back to formaldehyde under basic conditions, and formaldehyde is derivatized with 2,4-dinitrophenylhydrazine (DNPH) and quantified in its DNP hydrazone form using high-performance liquid chromatography-UV detection. The method detection limit at the 99% confidence level was 0.051 mg L(-1). A batch of samples can be processed within 4 h. The method has been applied to quantify the amount of formaldehyde in an analytical-grade acetone and in a commercial nail polish remover and the level of formaldehyde was found to be 0.175 and 0.184 mg L(-1), respectively.

In-injection port thermal desorption and subsequent gas chromatography-mass spectrometric analysis of polycyclic aromatic hydrocarbons and n-alkanes in atmospheric aerosol samples.

The traditional approach for analysis of aerosol organics is to extract aerosol materials collected on filter substrates with organic solvents followed by solvent evaporation and analytical separation and detection. This approach has the weaknesses of being labor intensive and being prone to contamination from the extracting solvents. We describe here an alternative approach for the analysis of aerosol alkanes and polycyclic aromatic hydrocarbons (PAHs) that obviates the use of solvents. In our approach, small strips of aerosol-laden filter materials are packed into a GC split/splitless injector liner. Alkanes and PAHs on the filter are thermally desorbed in the injection port and focused onto the head of a GC column for subsequent separation and detection. No instrument modification is necessary to accommodate the introduction of the aerosol organics into the GC-MS system. Comparison studies were carried out on a set of 16 ambient aerosol samples using our in-injection port thermal desorption (TD) method and the traditional solvent extraction method. Reasonably good agreement of individual alkanes and PAHs by the two methods was demonstrated for the ambient samples. The in-injection port thermal desorption method requires much less filter material for detecting the same air concentrations of alkanes and PAHs.

Concentrations of formaldehyde and other carbonyls in environments affected by incense burning.

Burning incense to pay homage to deities is common in Chinese homes and temples. Air samples were collected and analyzed for carbonyls from a home and a temple in Hong Kong where incense burning occurs on a daily basis. Carbonyls in the air were trapped on a solid sorbent coated with O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine, followed by thermal desorption and subsequent GC/MS analysis. The carbonyls identified include formaldehyde, acetaldehyde, acrolein, 2-furfural, benzaldehyde, glyoxal, and methylglyoxal. The levels of the above carbonyls correlate with the intensity of the incense-burning activities. The total mixing ratios of the carbonyls in the temple exceed those in the ambient air outside the temple by 11-23 times. Formaldehyde is the most abundant species, contributing to approximately 55% of the total carbonyl mixing ratios in both the temple and the home environments during incense burning. The mixing ratio of formaldehyde ranges from 108 to 346 ppbv in the temple and averages 103 ppbv in the home during incense burning. These values exceed the World Health Organization (WHO) air quality guideline of 100 microg m(-3) (88 ppbv) for formaldehyde. The highest formaldehyde level in the temple exceeds the WHO guideline by 3 times at peak incense burning hours. The mixing ratio of acrolein in the temple ranges from 20 to 99 ppbv, approaching or exceeding the WHO air quality guideline of 50 microg m(-3) (22 ppbv) for acrolein. Our measurements indicate that incense burning significantly elevates the concentrations of a number of carbonyls, most notably formaldehyde and acrolein, in the surrounding environments. This study provides preliminary insights on indoor air quality problems created by incense burning.