Measurement of atmospheric mercury speciation was conducted in a coastal city of the Yangtze River Delta, China from July 2013 to January 2014, in conjunction with air pollutants and meteorological parameters. The mean concentrations of gaseous elemental mercury (GEM), particulate bound mercury (HgP) and reactive gaseous mercury (RGM) were 3.26 ± 1.63 ng m−3, 659 ± 931 pg m−3, and 197 ± 246 pg m−3, respectively. High percentages of HgP during haze days were found, due to the increase in direct emissions and gas-particle partitioning of RGM. The average gas-particle partitioning coefficients (Kp) during moderate or severe haze days (PM2.5 > 150 μg m−3) were obviously decreased. GEM and HgP were positively correlated with PM2.5, SO2, NO2 and CO, suggesting a significant contribution of anthropogenic sources. Elevated HgP concentrations in cold seasons and in the morning were observed while RGM exhibited different seasonal and diurnal pattern. The ratio of HgP/SO2 and Pearson correlation analysis suggested that coal combustion was the main cause of increasing atmospheric Hg concentrations. The monitoring site was affected by local, regional and interregional sources. The back trajectory analysis suggested that air mass from northwest China and Huabei Plain contributed to elevated atmospheric Hg in winter and autumn, while southeast China with clean air masses were the major contributor in summer.

The effect of fireworks on the aerosol number characteristics of atmosphere was studied for an urban mega city. Measurements were made at 50 m height to assess the local changes around the festival days. Apart from the increase in total number concentration and characteristic accumulation mode, short-term increase of ultrafine particle concentration was noted. Total number concentration varies an order of magnitude during the measurement period in which peak occurs at a frequency of approximately one per day. On integral scale, it seems not possible to distinguish an episodic (e.g. firework bursting induced aerosol emission) and a normal (ambient atmospheric changes) event. However these events could be differentiated on the basis of size evolution analysis around number concentration peaks. The results are discussed relative to past studies and inferences are drawn towards aerosol signatures of firework bursting. The short-term burst in ultrafine particle concentration can pose an inhalation hazard.

Several pollutants, which include metals, are present in the Antarctic atmosphere, snow, marine and terrestrial organisms. This work reports the elements incorporated by Usnea sp thalli in Potter Peninsula, 25 de Mayo (King George) Island, South Shetlands, Antarctica. Geological origin was analyzed as possible sources of elements. For this purpose, correlations were done using a geochemical tracer, principal component analysis and enrichment factors were computed. Lithophile elements from particulate matter were present in most of the sampling sites. Bromine, Se and Hg showed the highest enrichment factors suggesting other sources than the particulate matter. Mercury values found in Usnea sp were in the same range as those reported for Deception Island (South Shetlands) and remote areas from the Patagonia Andes.

It has been known that substitution is not a suitable method to address non-detect (ND) data and can result in significant errors. However, reports of reliable statistical methods for handling ND data of polychlorinated dibenzo-p-dioxin/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in fish are rare. This work examines US-EPA's recommended statistical methods and traditional substitution-based methods for handling ND data in PCDD/F and DL-PCB datasets obtained from 240 fish samples. The Kaplan-Meier (KM) method was confirmed as a suitable statistical approach for dealing with our fish datasets. The results of the KM and substitution methods were compared; a significant difference was found in TEQs derived from KM and substitution for PCDD/Fs, suggesting that the handling of ND data is a critical issue for PCDD/Fs. For example, the substitution by ½LOD resulted in 20–25% overestimation of PCDD/F TEQs for fish samples with ND data (60–70%). In conclusion, the use of KM method is preferable for average TEQs, and if the use of KM is not applicable, substitution by zero is preferred. Based on this conclusion, the characteristics of fish contamination by PCDD/Fs and DL-PCBs in Korea were investigated.

Particulate matter data obtained from the national air quality monitoring network in China has become an essential and critical data source for many current and forthcoming studies as well as the formulation and implementation of air pollution regulatory policies on particulate matter (PM2.5 and PM10). However, the quality control of this data is dubitable and can affect many future studies and policies. This study identifies and elucidates two significant quality control issues with the data. They are PM2.5 levels exceeding concurrent co-located PM10 levels and the registration of same concentrations for consecutive hours at some stations. Future studies utilizing particulate matter data need to acknowledge and address these issues to ensure accurate and reliable results.

A thorough understanding of the labile status and dynamics of phosphorus (P) and iron (Fe) across the sediment-water interface (SWI) is essential for managing internal P release in eutrophic lakes. Fe-coupled inactivation of P in sediments is an important factor which affects internal P release in freshwater lakes. In this study, two in-situ high-resolution diffusive gradients in thin films (DGT) techniques, Zr-Oxide DGT and ZrO-Chelex DGT, were used to investigate the release characteristics of P from sediments in a large freshwater lake (Dongting Lake, China; area of 2691 km2) experiencing a regional summer algal bloom. Two-dimensional distributions of labile P in sediments were imaged with the Zr-Oxide DGT without destruction of the original structure of the sediment layer at four sites of the lake. The concentration of DGT-labile P in the sediments, ranging from 0.007 to 0.206 mg L−1, was highly heterogeneous across the profiles. The values of apparent diffusion flux (Fd) and release flux (Fr) of P varied between −0.027–0.197 mg m−2 d−1 and 0.037–0.332 mg m−2 d−1, respectively. Labile P showed a high and positive correlation (p < 0.01) with labile Fe(II) in the profiles, providing high-resolution evidence for the key role of Fe-redox cycling in labile P variation in sediments.

Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues to Lumbricus terrestris L. relative to the unamended control soil was assessed using 4-L soil microcosms with and without plant cover in a 48-day experiment. The use of aged dairy manure compost and biosolids compost was found to be effective, especially in the planted treatments, at lowering the bioavailability factor (BAF) by 18–39%; however, BAF results for DDT in the unplanted soil treatments were unaffected or increased. The pine chip biochar utilized in this experiment was ineffective at lower the BAF of pesticides in the soil. The US EPA Soil Screening Level approach was used with our measured values. Addition of 10% of the aged dairy manure compost reduced the average hazard quotient values to below 1.0 for DDT + DDE and dieldrin. Results indicate this sustainable approach is appropriate to minimize risks to wildlife in areas of marginal organochlorine pesticide contamination. Application of this remediation approach has potential for use internationally in areas where historical pesticide contamination of soils remains a threat to wildlife populations.

Studies indicated that occupationally exposed to metals could result in oxidative damage and inflammation and increase cardiovascular diseases risk. However, epidemiological studies about the associations of metals exposure with diabetes risk among coke oven workers were limited.This study aims to investigate the potential associations of 23 metals levels with the risk of diabetes among coke oven workers.The analysis was conducted in a cross-sectional study including 1493 participants. Urinary metals and urinary polycyclic aromatic hydrocarbons (PAHs) metabolites levels were determined by inductively coupled plasma mass spectrometer and gas chromatograph-mass spectrometer respectively. Multivariate logistic regression was used to investigate the associations of urinary metal levels with diabetes risk with adjustment for potential confounding factors including gender, age, BMI, education, smoking, drinking, physical activity, hypertension, hyperlipidemia and urinary PAHs metabolites levels.Compared with the normoglycemia group, the levels of urinary copper, zinc, arsenic, selenium, molybdenum, and cadmium were significantly higher in the diabetes group (all p < 0.05). Participants with the highest tertile of urinary copper and zinc had 2.12 (95%CI: 1.12–4.01) and 5.43 (95%CI: 2.61–11.30) fold risk of diabetes. Similar results were found for hyperglycemia risk. Besides, participants with the highest tertile of manganese, barium, and lead had 1.65(1.22–2.23), 1.60(1.19–2.16) and 1.45(1.05–1.99) fold risk of hyperglycemia when compared with the lowest tertlie.The results indicated that the urinary copper and zinc levels were positively associated with the risk of diabetes and hyperglycemia among coke oven workers. Urinary manganese, barium and lead levels were also associated with increased risk of hyperglycemia independently of other traditional risk factors. These findings need further validation in prospective study with larger sample size.

Rooftop and on-road measurements of O3, NO2, NOx, and CO concentrations were conducted to investigate the relationship between rooftop and on-road concentrations in a busy and shallow street canyon with an aspect ratio of ∼0.3 in Seoul, Republic of Korea, from 15 April to 1 May 2014. The median road-to-roof concentration ratios, correlation coefficients between rooftop and on-road concentrations, and temporal variations of rooftop and on-road concentrations are analyzed according to the rooftop wind directions which are two cross-canyon and two along-canyon directions. The analysis results indicate that the relationship is strong when the rooftop is situated on the downwind side rather than on the upwind side. Relative to the cross-canyon wind directions, one of the along-canyon wind directions can more enhance the relationship. A conceptual framework is proposed to explain the effect of ambient wind direction on the relationship between rooftop and on-road concentrations in a street canyon.

This study examined the short-term effects of temperature on cardiovascular hospital admissions (CHA) in the largest tropical city in Southern Vietnam. We applied Poisson time-series regression models with Distributed Lag Non-Linear Model (DLNM) to examine the temperature-CHA association while adjusting for seasonal and long-term trends, day of the week, holidays, and humidity. The threshold temperature and added effects of heat waves were also evaluated. The exposure-response curve of temperature-CHA reveals a J-shape relationship with a threshold temperature of 29.6 °C. The delayed effects temperature-CHA lasted for a week (0–5 days). The overall risk of CHA increased 12.9% (RR, 1.129; 95%CI, 0.972–1.311) during heatwave events, which were defined as temperature ≥ the 99th percentile for ≥2 consecutive days. The modification roles of gender and age were inconsistent and non-significant in this study. An additional prevention program that reduces the risk of cardiovascular disease in relation to high temperatures should be developed.