Background. Biological mechanisms contribute to the relationship between polycyclic aromatic hydrocarbon (PAH) exposure and infertility in males by altering semen quality. Objectives. The aim of the present study was to evaluate the impact of PAHs on male infertility using the sperm chromatin dispersion test (Halo sperm assay). Methods. Sixty-six (66) infertile males under 45 years of age were examined for the determination of urinary metabolite and oxidative stress by measuring lipid peroxidation and antioxidant activity of glutathione and glutathione-s-transferase, as well as hormonal activity of follicle stimulating hormone (FSH), testosterone and prolactin and semen quality. Results. There was an increased level of urinary metabolite of 1-hydroxy pyrene, 1-hydroxy naphthalene and 2-hydroxy naphthalene in the urine of the infertile group. In addition, elevated concentrations of malondialdehyde coincided with a decreased level of antioxidants, leading to oxidative stress in the infertile group. Semen samples showed 30% sperm deoxyribonucleic acid (DNA) fragmentation. Conclusions. The data provide strong evidence of a statistical threshold for semen samples containing 30% sperm DNA fragmentation resulting in a reduced level of pregnancy success. Participant consent. Obtained Ethics Approval. Study approval was given by the ethics committee of Alexandria University (United States Department of Health and Human Services, institutional review board registration (IRB), IORG0008812 Medical Research Institute, expires 4/8/2019, OMB No: 0990-0279). Competing Interests. The authors declare no competing financial interests.

Background. Furniture making industries are small scale businesses that commonly use organic solvents. There has been minimal focus on the health effects of this chemical hazard on the nervous system among furniture makers in Nigeria. Objectives. The present study aimed to assess the association between organic solvents exposure and neurobehavioral status of furniture makers, using electronic technicians as a comparison group. Methods. A comparative cross-sectional study design was employed. A sample size of 108 was calculated for each group. A semi-structured interviewer-administered questionnaire was used to obtain data on the socio-demographic variables and use of personal protective equipment (PPE). A proforma was developed to collect neurobehavioral assessment data. A checklist was used to assess the furniture makers' workshops. Air was sampled from all of the workshops in both the study and comparison groups to determine the concentration of total volatile organic compounds (TVOCs). Results. The use of PPE was poor in both the study and comparison groups, with no significant difference between them (34.4% and 37.7% respectively). Total volatile organic compound and formaldehyde (HCHO) concentrations were significantly higher at the furniture makers' workshops compared with electronic technicians (p<0.001) for both chemicals. The 8-hour time-weighted average of TVOC was also higher in the furniture makers' workshops (4.4±0.6 mg/m3) compared with the control group (0.3±0.3 mg/m3). The neurobehavioral symptoms score was significantly higher among the study group relative to the comparison group (p<0.001). There was a significant difference in the outcome of the auditory verbal learning test, total recall (p=0.005), and delayed recall (p=0.003). There was no significant association between solvent exposure index and findings from the simple reaction time test Conclusions. Poor compliance with the use of PPE among furniture makers may increase their exposure to organic solvents. There were more neurobehavioral changes in the furniture makers with a higher exposure index. Measures are needed to educate artisans about workrelated chemical hazards and ensure compliance with basic occupational safety and hygiene standards. Participant Consent. Obtained Ethics Approval. Ethics approval was obtained from the Health Research and Ethics Committee of the Institute of Public Health, Obafemi Awolowo University (IPH/OAU/12/1049). Competing Interests. The authors declare no competing financial interests.

Background. Lead acid batteries are widely used, dependable, and inexpensive. Lead from these batteries can contaminate the surrounding ecosystem due to improper disposal and contribute to lead poisoning. Lead poisoning is an important public health issue that can cause adverse human health impacts. Objectives. The present study aimed to assess exposure to lead released from automobile repair shops handling lead acid batteries in the city of Dhaka, Bangladesh, as well as shop owner and worker perceptions of lead pollution. Methods. Ten dust samples were collected for atomic absorption spectrophotometer analysis to determine the concentration of lead. In addition, a questionnaire survey (N=75) was conducted to determine the level of knowledge of lead exposure and associated risks. Results. Lead contamination was found in all dust samples, with lead concentrations ranging from 11.40 ppm to greater than 1000 ppm. In addition, 80% of respondents did not have any knowledge about the harmful effects of lead pollution. Conclusions. The present study suggests the importance of defining permissible air lead levels and improving worker education on lead pollution. Ethics Approval. The study was approved by the Ethics Committee of the Department of Environmental Science, Stamford University, Bangladesh. Competing Interests. The authors declare no competing financial interests.

Raw coal fly ash (RCFA) was recycled as three kinds of adsorbents by hydroxyl anion (OH⁻), hydrogen ion (H⁺), and thermal activation, respectively, for the adsorption of Cr(VI) from water. The H⁺ activation can explore the adsorptive potential of RCFA more effectively than the other two methods. The specific surface areas of the adsorbents are 12.33, 16.32, and 13.89 m² g⁻¹ for OH⁻, H⁺, and thermal activation, respectively. The adsorption process follows the pseudo-second-order kinetic model and the Langmuir model better and exhibits exothermic property. The activation energy (20.65–31.88 kJ mol⁻¹) and the negative Gibbs free energy reveal that the adsorption is a physical and spontaneous process. The adsorbents derived from OH⁻, H⁺, and thermal activation can be used at least 5, 7, and 4 times, respectively, while the one from H⁺ activation has the best adsorption capacity (6.41 μg g⁻¹ for the first run). The adsorption process can introduce other metallic/toxic elements, but within the Chinese standard. The preparation cost of the H⁺ activation is $1103 ton⁻¹ adsorbent, while the treatment cost is $1.6 ton⁻¹ water. The more accurate parameters in the pseudo-second-order kinetic model and Langmuir model can be calculated by nonlinear method and provided by the error function of the sum of the squares of the errors.

Commercial activated carbon fiber (ACF) has been employed as particle electrodes to degrade aqueous m-cresol in 3-D electrode systems. To enhance the electrooxidation performance, three types of new ACF modification modes (anodic oxidation, cathodic reduction, and aqueous oxidation with concentrated HNO₃) were introduced in this paper. These pretreated samples were characterized by N₂ adsorption, scanning electron microscopy (SEM), cyclic voltammetry (CV), temperature-programmed desorption mass (TPD-MS), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FT-IR). It was revealed that the two new modification methods could efficiently modify the surface morphology as well as the chemical property. Eight types of surface oxygen groups (SOGs) were identified on the surface of ACF, and the types and amount of SOGs might be related to the oxidation effect of ACF on the 3-D electrodes. The effect and mechanism of these SOGs on electrooxidation performance were discussed with the aid of the frontier molecular orbital theory. It was demonstrated that the H₂O₂–·OH reaction mechanism was improved in the 3-D electrode system and the mechanism was elucidated.

To deliver accurate particulate matter information to citizens, a detailed particulate matter dispersion model including factors such as land use and meteorological information was developed and used to create particulate matter concentration distribution maps for Daejeon Metropolitan City (South Korea). The results showed differences from existing particulate matter concentration distribution maps created using established methods. For PM2.5, approximately 3600 concentration maps were constructed. Taking a map as an example, according to existing methods, the PM2.5 concentration was “good” in 56% and “moderate” in 44% of areas. However, according to our modeling, the PM2.5 concentration was good in 31%, moderate in 26%, “unhealthy” in 28%, and “very unhealthy” in 15% of areas. Furthermore, the existing methods indicated that no portion of the population was exposed to poor particulate matter concentrations, while the proposed model found that over 170,000 people were exposed to such concentrations. These results will contribute to sustainable urban and environmental planning.

Multi-level ditch area is a major component of the hydrographic net of plain area, China. Given the high concentration of nitrogen (N) in the surface water and vigorous biogeochemical interactions, ditch is likely to be the hot spots of N₂O emission. However, N₂O emission flux and emission factor (EF₅ᵣ) of multi-level ditches have not been determined. To address this knowledge gap, a 1-year field work in three ditches with different levels in Chengdu Plain was conducted. It is found that the annual flux of N₂O emission and EF₅ᵣ was higher in the lateral (0.0020 and 83.94 μg m⁻² h⁻¹) and field ditches (0.0019 and 110.75 μg m⁻² h⁻¹) than in the branch ditch (0.0016 and 46.38 μg m⁻² h⁻¹, P < 0.05). It is found that parameters of groundwater level, discharge, precipitation, and NH₄⁺ were the primary factors, and these parameters can model the N₂O flux well. Furthermore, the content of NH₄⁺ in the surface water of ditches presented better correlation with the emission of N₂O than the content of NO₃⁻. Therefore, controlling NH₄⁺ emission and lessening fertilizer usage in summer may be key solutions for indirect reduction of N₂O in Chengdu Plain.

The adverse effects of air emissions from animal feeding operations (AFOs) on public health, environment, and quality-of-life have been well-documented. Regulations or lawsuits may force AFOs to reduce their air emissions. Since livestock barn particulate matter (PM) has relatively high particle density and diameter and many gasses adsorb onto PM, its filtration might reduce air emissions. A porous windbreak wall that imposes acceptable backpressure (< 12.5 Pa) and covers the fan could be a promising option. Seventy-two different porous windbreak wall scenarios were modeled to compare their backpressure on the fan as well as average airspeed over the ground. These scenarios were combinations of shape (box, chamfered, curved), size (lengths of 2, 2.5, and 3 fan diameters), presence or absence of an opening (opened and closed), screen porosity (mosquito screen or clean screen, SunBlocker 70% or clogged screen), and fan angle and height. Backpressure and airspeed decreased with increasing windbreak wall length. Generally, the box-shaped windbreak wall had lower backpressure and airspeeds than the other shapes. The increased backpressure with clogged screen even at two fan diameters (2d) was acceptable. The tilted fan commonly used in poultry houses had higher backpressure and airspeed over the ground than the non-tilted fan used in swine houses due to the former’s lower surface area and tilt towards the ground. Overall, taking into account cost considerations and footprint size (for retrofittability), despite its higher airspeed over the ground (vs. larger footprints) and modest reduction in airflow rate, the 2d, open box model seems the most promising option.

Triclosan (TCS) is a potential endocrine-disrupting compound (EDC), which produces an adverse impact on aquatic life and human beings. Wastewater discharge is considered as the primary source of triclosan in water bodies. The study is aimed to investigate the occurrence and environmental risk of triclosan released by municipal wastewater treatment plants (WWTP). An analytical protocol was developed and validated to determine the presence of TCS in the samples through offline solid-phase extraction (SPE) and liquid chromatography - electron spray ionization (ESI)—quadrupole mass spectrum (LC/ESI/MS). The limit of detection and quantification of protocol was estimated as 2.8 ng/L and 6.25 ng/L, respectively. The season-wise influent and effluent samples from two WWTP in Chennai, India, were monitored. The TCS concentrations in samples were found in the range of 443 to 1757 ng/L. The Risk Quotient (RQ) method was performed to evaluate the environmental (ecotoxicological and human health) risk associated with the exposure of TCS-containing wastewater. The results of the study revealed that primary producer (algae) was highly vulnerable to exposure of TCS in the aquatic environment. The estimated daily intake of TCS was much lower than the reference dosage, and this indicates that TCS did not produce any considerable risk to human health. Also, it suggested that additional treatment was required for complete removal of triclosan residues.

Residues from mining, as metabasalt powder from amethyst exploration, can be used to improve soil properties. Although there is a high-load content of clay minerals in metabasalt, the effects of this residue on cooper (Cu²⁺) and zinc (Zn²⁺) sorption and desorption have not been studied. The aim of this work was to evaluate Cu²⁺ and Zn²⁺ sorption capacity of metabasalt powder and to discuss the mineralogical behavior facing this phenomenon. This residue sorption capacity was compared to reference clay minerals under two Cu²⁺ and Zn²⁺ concentrations (8 and 16 cmolc/kg) in a competitive system (Cu²⁺ + Zn²⁺). The sorption capacity was estimated by sequential desorption using cation exchange resin. A survey of mineralogical and Cu²⁺ and Zn²⁺ concentrations was performed on metabasalt before and after sorption, and after desorption tests. All materials sorbed higher amounts of Cu²⁺ than Zn²⁺. The sorption magnitude decreased in the following order: metabasalt > montmorillonite > illite > kaolinite. Cu²⁺ and Zn²⁺ desorption from metabasalt is lower than the standard clay minerals, since the metabasalt sorption sites are expandable interlayers of clay minerals. The relevance and application of our findings are critical in providing information for the management of metabasalt residue, suggesting potential use as a remediation agent in contaminated water, especially those with high Cu²⁺ and Zn²⁺ loading. It also suggests that the Cu²⁺ and Zn²⁺ enrichment of this residue could potentially be used for converting the metabasalt into a useful source of slow nutrient supply for agricultural soils.