Background. Pollution in aquatic ecosystems is a serious environmental concern. There is a great need for constant assessment and monitoring of hazardous substances, particularly in aquatic environments in developing countries, as rivers are media with easy trans-boundary transport of chemical substances. Objectives. The present study assessed the occurrence and distribution of organochlorine pesticides (OCPs) in the sediments of the Niger River, Nigeria. Methods. A total of 120 samples of sediment were collected from 15 locations along the river using Van Veen grab. The Environmental Protection Agency (USEPA) 3570 method with slight modification was used for sample preparation. Organochlorine pesticides were analyzed using Hewlett Packard 5890 series II gas chromatography with electron capture detector. Confirmation of OCPs was performed using a gas chromatograph/mass spectrometer (Shimadzu QP2010) and capillary column type HP1MS (30 m × 0.25 um × 0.25 mm id). Results. The highest concentration of ∑OCPs in the sediment samples of the River Niger (5023±1596 μg/kg, 4672–7009 μg/kg) was detected in a location at Onitsha, while the lowest concentration (1570±204.5, 1214–1820 μg/kg) was detected in a location at the Nicolas River. Discussion. High values of ∑OCPs (>2000 μg/kg) were detected in all of the locations except in three locations where lower levels were detected. The ∑OCPs were higher during the dry season compared to the rainy season. This may be because the resident time of the sediment transported was higher during the dry season compared to the rainy season, which is characterized by storms, high current, and bottom scour. The chlordane concentration ranged between 24.4 and 134.1 μg/kg dry weight (dw) in locations Nicolas 14 and Lokoja 5; and the Probable Effect Concentration guidelines were exceeded. Dieldrin was detected at very low levels in most of the locations and ranged from 5.67 to 70.3 μg/kg dw in locations Onitsha 9 and 8; and the Probable Effect Concentration guideline was only exceeded in location Onitsha 8; however, the Toxic Effect Concentration guideline was exceeded at all of the locations. Dichlorodiphenyldichloroethane (DDD) was not detected in location Lokoja 6 or 7, and Onitsha 8 and 9, although the concentration in all other locations exceeded the guidelines. Dichlorodiphenyldichloroethylene (DDE) concentrations exceeded the guidelines except in location Nicolas 13. Conclusions. Due to the environmental/human risk and potential danger of the elevated levels of OCPs, there is a need for continuous monitoring of the Niger River. Competing Interests. The authors declare no competing financial interests.

Background. Evidence from various epidemiological studies has shown an association between particulate matter 2.5 (PM2.5) and diabetes mellitus. A prospective study from the United States reported that exposure to PM2.5 alters endothelial function, and leads to insulin resistance and reduction in peripheral glucose uptake. There is a paucity of data on the relation between air pollution and diabetes in low- and middle-income countries. Objectives. To estimate the prevalence of type 2 diabetes among people living in areas with higher exposures of suspended PM2.5 compared to people living in areas with lower exposures in Chennai, Tamil Nadu, India. Methods. A cross-sectional study was carried out in two areas of Chennai city. The PM2.5 affecting vulnerable areas were stratified from a list of air quality monitoring stations in Tamil Nadu Pollution Control Board and Central Pollution Control Board. The highest and lowest areas of exposure were selected from the list. Households were randomly selected for the study. A total of 201 (67 male, 134 female) individuals from a high exposure area (HEA) and 209 (76 male 133 female) individuals from a low exposure area (LEA) were recruited for the study. Adults over 18 years of age were screened for random capillary blood glucose (RCBG) by glucometer (OneTouch Ultra). Results. The prevalence of diabetes (34.8% vs 19.6% p =0.001) was 77.5% higher among people living in areas of high particulate matter exposure compared to people living in less exposed areas. Multivariable logistic regression analysis showed that age, gender, residential area, and family history of diabetes were significantly associated with the prevalence of diabetes (p<0.05). Conclusions. The present study indicates a link between high levels of exposure to PM2.5 and diabetes mellitus. Further prospective studies on populations exposed to elevated pollution are needed to establish whether this association has a causative link. Participant Consent. Obtained Ethics Approval. The study was approved by the Ethics Committee of the Prof. M Viswanathan Diabetes Research Centre, Chennai, India Competing Interests. The authors declare no competing financial interests.

Background. Water supplies can be contaminated by anthropogenic activities. The poultry industry uses a variety of heavy metals as additives in chicken feed, but excretion, runoff and dumping of heavy metals can threaten water bodies and have adverse effects on human health. Objectives. The aim of the present study was to determine the environmental impact of heavy metals from poultry waste discharged into the Olosuru stream, located in Ikire, southwest Nigeria. Methods. In order to study changes in heavy metal loads, samples were collected six times during the wet season (September, October 2014 and April 2015) and dry season (November 2014, January and February 2015). The inhabitants of Olosuru village use water for domestic and agriculture purposes from the Olosuru stream which is located only a few meters from a poultry farm discharge point. Three stations were sampled, upstream to downstream, with 500 meter distance between each point. Results. Selected heavy metals concentrations in the Olosuru stream were all above the World Health Organization (WHO) standard for drinking water. The highest mean concentrations of heavy metals were recorded at the downstream station, while arsenic, iron and lead showed significant spatial and seasonal differences. Seasonally, the highest iron concentrations were recorded in the dry season (0.104±0.401 mg/L), while the mean concentrations of other heavy metals recorded during the sampling period were higher during the wet season. Conclusions. Concentrations of heavy metals in the present study were above acceptable limits. Poultry waste discharged into the Olosuru stream, can have negative impacts on the stream and health implications for local residents. Competing Interests. The authors declare no competing financial interests.

Background. High concentrations of total petroleum hydrocarbons (TPH), iron (Fe), and manganese (Mn) were identified in soil samples from two shipyards where vessel dismantling activities take place in Tanjungjati Village, Indonesia, and subjected to bioremediation. Objectives. The aim of the present study was to determine whether the combination of surfactant solution, bioaugmentation (a consortium of Bacillus subtilis and Acinetobacter lwoffii), and biostimulation (nutrient amendment and aeration intermittent) would reduce TPH, Fe, and Mn levels from soil contaminated from ship dismantling activities. Methods. Iron and Mn bioavailability were examined according to the Indonesian technical guidelines for soil chemical analysis with the help of atomic absorption spectrophotometry. The n-hexane solvent soil was extracted using the ultrasonic water bath method for TPH analysis. Results. The highest removal results achieved were TPH (69.62%), Fe (87.10%), and Mn (29%) for Soil 1 samples and elimination of TPH (28.80%), Fe (65.10%), and Mn (57.38%) for Soil 2 samples using a combination of surfactant solution, bioaugmentation, and biostimulation (nutrient amendment and without aeration intermittent). Iron and Mn removal in the controls was higher than in the treated soils, which showed that Fe and Mn could decrease naturally in both contaminated soils. Conclusions. The present study showed that bioremediation using a combination of surfactant solution, a consortium of Bacillus subtilis, and Acinetobacter lwoffii, as well as a nutrient amendment, has the potential to degrade hydrocarbons in contaminated soil. Furthermore, Bacillus subtilis and Acinetobacter lwoffii consortium used for bioaugmentation have the potential to enhance the degradation of hydrocarbons in soil. Competing Interests. The authors declare no competing financial interests.

Background. The worldwide emergence of multi-drug resistant bacteria has become a health crisis, as fewer or sometimes no antimicrobial agents are effective against these bacteria. The Rio Grande River is the natural boundary between the United States (US) and Mexico. It spans a border region between Texas, New Mexico and Mexico. Underserved populations on the Mexican side use the river for recreational purposes, while on the US side, the river is used for irrigation and as a source of drinking water. Objectives. The purpose of the present study was to evaluate the concentration of antibiotic residues, to determine the presence of genetic elements conferring antibiotic resistance and to characterize multi-drug resistant bacteria in the waters of the Rio Grande River. Methods. Water samples were obtained from the Rio Grande River. Deoxyribonucleic acid (DNA) was extracted from both isolated bacteria and directly from the water. Amplification of selected genetic elements was accomplished by polymerase chain reaction. Identification and isolation of bacteria was performed through MicroScan autoSCAN-4. Fecal contamination was assessed by IDEXX Colilert. Antibiotic residues were determined by liquid chromatography and mass spectrometry. Results. Antibiotics were found in 92% of both water and sediment samples. Antibiotic concentrations ranged from 0.38 ng/L - 742.73 ng/L and 0.39 ng/l - 66.3 ng/g dry weight in water and sediment samples, respectively. Genetic elements conferring resistance were recovered from all collection sites. Of the isolated bacteria, 91 (64.08%) were resistant to at least two synergistic antibiotic combinations and 11 (14.79%) were found to be resistant to 20 or more individual antibiotics. Fecal contamination was higher during the months of April and July. Conclusions. The 26 km segment of the Rio Grande River from Sunland Park NM to El Paso, TX and Juarez, Mexico is an area of concern due to poor water quality. The presence of multidrug resistant bacteria, antibiotics and mobile genetic elements may be a health hazard for the surrounding populations of this binational border region. Policies need to be developed for the appropriate management of the environmental natural resources in this border region. Competing Interests. The authors declare no competing financial interests.

The present systematic experiment was conducted to estimate the impact of behavioral and pathological indices on freshwater fish Channa punctatus exposed to sub-lethal concentration (5 ppm) of an organophosphorus insecticide chlorpyrifos (CPF). Fish were segregated into four experimental groups (G1, control; G2, 10 days; G3, 20 days; and G4, 30 days exposure), each group comprises 15 fish in triplicate. The behavioral and histological changes were assessed in each group. Severe behavioral changes were observed in the 30 days, moderate changes in the 20 days, and mild changes in the 10 days exposure groups respectively when compared with the control group. The pathologic lesions such as inter lamellae space, necrotic lamellae, fused lamellae, and lifting of lamellae epithelium in gills; vacuolation, blood conjunctions, and necrotic hepatocytes in the liver; and lamina propria, fusion of villi, and flattened villi in the intestine were observed. These structural alterations of the gills, liver, and intestine could affect respiration, osmotic and ionic regulation; absorption, storage and secretion; digestion; and absorption of nutrients respectively, which in turn could adversely affect the growth and survival of freshwater fish Channa punctatus. This study serves as a biomonitoring tool for the effects of organophosphorus insecticide CPF on the aquatic biota.

Polycyclic aromatic hydrocarbons (PAHs) are toxic organic pollutants and omnipresent in the aquatic and terrestrial ecosystems. A high-efficient pyrene-degrading strain CP13 was isolated from activated sludge and identified as Mycobacterium gilvum based on the analysis of 16S rRNA gene sequence. More than 95% of pyrene (50 mg L⁻¹) was removed by CP13 within 7 days under the alkaline condition. Pyrene metabolites, including 4-phenanthrenecarboxylic acid, 4-phenanthrenol, 1-naphthol, and phthalic acid, were detected and characterized by GC-MS. Results suggested that pyrene was initially attacked at positions C-4 and C-5, then followed by ortho cleavage, and further degraded following the phthalate metabolic pathway. Analysis of pyrene-induced proteins showed that the extradiol dioxygenase, a key enzyme involved in pyrene degradation, was highly up-regulated in pH 9 incubation condition, which illustrated the high efficiency of CP13 under alkaline environment. The present study demonstrated that the isolated bacterial strain CP13 is a good candidate for bioremediation of alkaline PAH-contaminated sites.

The aim of this study was to determine the distribution of cadmium (Cd) and lead (Pb) in muscle and liver tissue of Haemulopsis axillaris and Diapterus peruvianus from the Eastern Pacific in Mexico and to assess the health risk to consumers. Fish were collected as bycatch on the continental shelf between the coasts of Sinaloa and Guerrero (Eastern Pacific). Cd and Pb were quantified in muscle and liver tissue using graphite-furnace atomic absorption spectrophotometry (GF-AAS).Concentration of Cd was greater in muscle tissue than in liver tissue; with Pb, however, the opposite pattern was found. The highest concentration of Cd (0.177 μg g⁻¹) was found in muscle tissue of H. axillaris from Sinaloa. For Pb, the highest level (0.692 μg g⁻¹) was found in the liver tissue of H. axillaris also from Sinaloa. Levels of Cd and Pb in muscle tissue were both below Mexican Guidelines (0.5, 1.0 μg g⁻¹ wet weight for Cd and Pb respectively) and International Guidelines. The hazard index (HI) for both metals in the edible portion of studied considering metal levels in the edible portion and the rate of fish consumption by the Mexican population (in adults and children) was less than 1 (HI < 1), values which do not represent a health risk to consumers.

In the present scenario, the utilization of petroleum fuel is expanding forcefully worldwide in the vitality store and plays a highly hazardous role in the ecological system. Biofuel stands out among the most tenable keys for this issue. The lemongrass oil is used as a biofuel because of low density and viscosity when compared with diesel. The lemongrass oil is extracted by steam distillation process. In the present investigation, partially stabilized zirconium, due to its higher thermal conductivity, is selected as coating material. The top surface of the piston and the inlet and exhaust valves are coated up to the preferred thickness of 500 μm by the plasma spray technique. The lemongrass emulsion fuel is prepared in the proportion of 94% of lemongrass oil, 5% of water, and 1% of surfactant span 80. The nanoparticles of cerium oxide were used with lemongrass oil (LGO) nano-emulsion in the measurement of 30 ppm. The four-stroke diesel engine execution, ignition, and the outflow extent were contrasted in the diesel and lemongrass oil (LGO) compared with the base diesel engine. The performance characteristic curves of lemongrass-cerium oxide nano-emulsion fuel show the increase in brake thermal efficiency of 17.21% when compared with the mineral diesel fuel. The emission characteristics of lemongrass-cerium oxide nano-emulsion fuel show a drop in hydrocarbon and carbon monoxide emission by 16.21% and 15.21%, respectively, when compared with base diesel fuel and also there is a decrease in oxides of nitrogen and smoke emission by 24.1% and 6.3%, respectively, when compared to mineral diesel fuel.