Soil degraded by coal mining activities can be remediated by amendment with agro-industrial organic sludge. However, the environmental impacts associated with this management practice must be properly addressed. In this context, the objective of this study was to evaluate the eco(geno)toxicity of a fresh and a stabilized sludge before use in a laboratory soil remediation test. Chemical analysis of the complex mixtures (degraded soil, fresh sludge, and stabilized sludge) was carried out, as well as a battery of eco(geno)toxicity tests on microbiological enzymes (fluorescein hydrolysis), earthworms, and higher plants (including Vicia faba genotoxicity test), according to published methodologies. The results of these tests showed that fresh sludge was more toxic than sludge stabilized over 6 months toward earthworms and higher plants (lettuce, corn, and wild cabbage), while phyto(geno)toxicity tests with V. faba indicated the same genotoxicity levels for the two types of sludge. In the soil remediation simulation using different mixtures of degraded soil and stabilized sludge, the proportions of 50:50 % (dry weight basis) provided the lowest phyto(geno)toxicity effects and this mixture can be used for the revegetation of the contaminated site.

In this study, we have considered the relationship between the spatial configuration of land use and water quality in the Three Gorges Reservoir Area. Using land use types, landscape metrics, and long-term water quality data, as well as statistical and spatial analysis, we determined that most water quality parameters were negatively correlated with non-wood forest and urban areas but were strongly positively correlated with the proportion of forest area. Landscape indices such as patch density, contagion, and the Shannon diversity index were able to predict some water quality indicators, but the mean shape index was not significantly related to the proportions of farmland and water in the study area. Regression relationships were stronger in spring and fall than in summer, and relationships with nitrogen were stronger than those of the other water quality parameters (R ² > 0.80) in all three seasons. Redundancy analysis showed that declining stream water quality was closely associated with configurations of urban, agricultural, and forest areas and with landscape fragmentation (PD) caused by urbanization and agricultural activities. Thus, a rational land use plan of adjusting the land use type, controlling landscape fragmentation, and increasing the proportion of forest area would help to achieve a healthier river ecosystem in the Three Gorges Reservoir Area (TGRA).

Heat pretreatment process can promote sludge hydrolysis and enhance the degradability of waste sludge. The effect of heat pretreatment at different temperatures on the changes of soluble chemical oxygen demand (SCOD), carbohydrates, and proteins and the structural and functional properties of organics in extracellular polymeric substances (EPS) and dissolved organic matters (DOM) were systematically investigated. Heat pretreatment was conducted at 65, 80, 100, and 121 °C for 30 min. The SCOD in DOM increased with pretreated temperatures. Three-dimensional excitation–emission matrix (3D-EEM) fluorescence spectroscopy was utilized to evaluate the biodegradable and non-biodegradable components in EPS and DOM. Moreover, the humification index (HIX) and the fluorescence index (FI) were used to evaluate the humification and DOM source. At 80 °C, the percent fluorescence response (P ᵢ,ₙ) of easily biodegradable soluble microbial by-product substance was higher than others; meanwhile, little non-biodegradable humic acid-like substance was accumulated. In order to enhance sludge biodegradability, 80 °C was chosen as the optimal temperature for heat pretreatment.

Formaldehyde (FA) is an aldehyde used in antiseptics and adhesives. The World Health Organization (WHO) and other institutes have linked FA to sick building syndrome and allergic diseases. Recent studies have reported that cadavers embalmed using formalin and ethanol-based preservative solutions release FA vapor during dissection and that FA vapor may adversely affect students and lecturers in gross anatomy laboratories. However, few details have been reported correlating dissection stage with increased FA vapor release. In this study, we evaluated the vapor level of FA released in each dissection stage. Six cadavers for which consent was given for use in anatomy research and education were examined in this study. Using an active sampling method, FA vapor was collected above the thoracoabdominal region of each dissected cadaver. FA was eluted from each sampler using acetonitrile and analyzed by high-performance liquid chromatography. Our data show that FA levels significantly increase after skin incision and that the vapor level of FA released differs between male and female cadavers. We also found that subcutaneous adipose tissues of the thoracoabdominal-region release FA vapor and that female cadavers release significantly higher levels of FA per kilogram of subcutaneous adipose tissue than do male cadavers. Based on these data, we propose the methods be developed to prevent exposure to FA vapors released from cadavers.

The concentrations and characteristics of 16 polycyclic aromatic hydrocarbons (PAHs) in 48 oil samples randomly collected from 30 catering services that employ six cooking methods were quantified via high-performance liquid chromatography (HPLC). These 16 PAHs were detected in almost all of the samples. The levels of Σ16PAHs, Σ4PAHs, benzo[a]pyrene (BaP), and total BaP equivalents (ΣBaPₑq) for the six cooking methods exceeded the legal limit. The concentrations of Σ4PAHs were approximately 9.5 to 16.4 times the legal limit proposed by the European Commission (Off J Eur Union 215:4–8, 2011), and the level of BaP exceeded the national standard in China by 4.7- to 10.6-fold, particularly in oil from fried foods. Low molecular weight PAHs (LMW PAHs) were predominant in fried food oil from different catering services and accounted for 94.8 % of these oils, and the ΣBaPₑq of the high molecular weight PAHs (HMW PAHs) was 11.5-fold higher than that of the LMW PAHs. The concentrations of Σ16PAHs (3751.9–7585.8 μg/kg), Σ4PAHs (144.6–195.7 μg/kg), BaP (79.7–135.8 μg/kg), and ΣBaPₑq (231.0–265.4 μg/kg) were highest in the samples from fast food restaurants/buffets (FB), followed by those from fried food stalls (FS) and then cooking restaurants/cafeterias (RC). The results of this study suggest that the government should strengthen control and supervision of PAH contamination in food and edible oils.

Mercury is a toxic trace metal, which can accumulate to levels threatening human and environmental health. In this study, contents of total mercury have been determined by ICP-MS spectrometry in fresh and processed tuna (110 samples) purchased from supermarkets in NW Spain. Mercury was present in all samples analyzed; however, only one sample of fresh tuna (1.070 mg kg⁻¹ wet weight (w.w.)) slightly exceeded the limit of the EU (1.0 mg kg⁻¹ w.w.). The average mercury concentration in processed tuna was lower than fresh, 0.306 mg kg⁻¹ w.w., and ranged from 0.080 to 0.715 mg kg⁻¹ w.w. Results were compared with literature data. In regard to the three types of preparation-packaging media for canned tuna, total Hg content was found in the following order: olive oil > natural > pickled sauce; the last showed significant statistical differences (p < 0.01) with the other two preparations. Between the two evaluated canned tuna species, significant statistical differences (p = 0.008) were observed and Thunnus alalunga presented a greater mean content (0.332 ± 0.114 mg kg⁻¹ w.w.) compared to Thunnus albacares (0.266 ± 0.171 mg kg⁻¹ w.w.).Taking into account the AESAN recommendation for adults and children, as well as the EU regulations and the tuna consumption by the Spanish population, the Hg levels obtained in this study pose no risk to consumer health. However, additional studies, a monitoring process, and efforts to reduce Hg concentration in tuna would be necessary, as well as considering other sources of exposure to Hg.

Oil fly and boiler ash samples were collected from the four major Egyptian power plants in order to determine their natural radioactivity. Secular equilibrium between ²³⁸U and ²³²Th and their decay products is significantly disturbed in oil ash samples. The ²²⁶Ra/²³⁸U ratios were between 440 and 1993 with an average value of 801, indicating that the concentrations of daughters ²²⁶Ra were very high compared to the parent ²³⁸U in the oil ash samples. While, the average ratios for ²¹⁰Pb/²²⁶Ra in most samples were 1.19 ± 0.05, indicating a secular equilibrium in the ²²⁶Ra–²¹⁰Pb sub series. The natural radioactivity due to ²³⁸U and ²³²Th was found to be negligible. While the activity concentrations of ²²⁶Ra ranged from 3205 to 12,320 Bq kg⁻¹ with an average value of 9284 Bq kg⁻¹, ²¹⁰Pb ranged from 5960 to 13,930 Bq kg⁻¹ with an average value of 11,513 Bq kg⁻¹. The results are compared with the reported data from other countries. The average value of radium equivalent activity was 9308 ± 2729 Bq kg⁻¹, while the external and internal hazard indexes were found to be 25 ± 7 and 50 ± 15, respectively. All the studied radiological parameters were higher than the recommended limit by the IAEA in all ash samples.

Nonionic surfactant-modified clay is a useful absorbent material that effectively removes hydrophobic organic compounds from soil/groundwater. We developed a novel material by applying an immobilized fungal laccase onto nonionic surfactant-modified clay. Low-water-solubility polycyclic aromatic hydrocarbons (PAHs) (naphthalene/phenanthrene) were degraded in the presence of this bioactive material. PAH degradation by free laccase was higher than degradation by immobilized laccase when the surfactant concentration was allowed to form micelles. PAH degradation by immobilized laccase on TX-100-modified clay was higher than on Brij35-modified clay. Strong laccase degradation of PAH can be maintained by adding surfactant monomers or micelles. The physical adsorption of nonionic surfactants onto clay plays an important role in PAH degradation by laccase, which can be explained by the structure and molecular interactions of the surfactant with the clay and enzyme. A system where laccase is immobilized onto TX-100-monomer-modified clay is a good candidate bioactive material for in situ PAHs bioremediation.

The present study was designed to study the effect of brick kilns emissions on the reproductive health and biochemical status of brick kiln workers and people living in the area near brick kilns. Body mass index (BMI) was significantly reduced in brick makers, carriers, and bakers compared to the control. Red blood cells count and hematocrit (%) were significantly high in brick bakers while MCH was significantly reduced in brick makers and brick bakers. Heavy metals (lead, cadmium, and chromium) concentration in whole blood of the brick kiln workers were significantly higher as compared to the control. Antioxidant enzymes (CAT, SOD, POD, GSH, and GR) were significantly reduced in brick kiln workers as compared to the control while TBARS level were significantly high in brick bakers as compared to the control. Plasma leutinizing hormone (LH) was significantly high in brick bakers while testosterone concentrations were significantly reduced in brick makers, carriers, and bakers. The present study shows that brick kiln workers and people living in the brick kiln vicinity are exposed to heavy metals and other pollutants that is a serious threat to their health. Alternate technology is needed to be developed and brick kilns should be replaced.