Fish actively form shoals, which is a behavior highly sensitive to experimental changes in environmental conditions. Here we evaluated the potential for using the shoaling behavior of red crucian carp as an early-warning biosensor system for assessing water quality. To reliably characterize shoaling behavior, we propose a novel method for determining the size of the shoal based on a Delaunay triangle network. We examined the effect of group size (two to 10 fish) in the shoaling paradigm and evaluated whether measurements of shoaling behavior could be used to assess water quality using test fish exposed to chemicals. The test chemicals were sodium hydroxide (NaOH), hydrochloric acid (HCl) and glyphosate, which are commonly used in agriculture or industry. There was a significant effect of group size on the shoaling behavior of unexposed fish. Furthermore, NaOH (20 mg/L), HCl (20 mg/L) and glyphosate at three concentrations (0.1 mg/L, 0.05 mg/L and 0.025 mg /L) significantly decreased shoaling behavior relative to controls. The average alarm time in response to a change in water quality was about 21 min. We conclude that the shoaling behavior of red crucian carp is a useful tool for monitoring water quality.

Background: Children’s exposures to arsenic (As), lead (Pb), mercury (Hg), and cadmium (Cd) are of particular concern in early-life. Exposures to heavy metals are traditionally measured in whole venous blood, which is costly and invasive. As an alternative we describe a method for quantifying As, Pb, Hg, and Cd in dried blood spot (DBS) samples. Objectives: To validate a method for quantifying levels of As, Pb, Hg, and Cd in finger-stick DBS samples. Background metal contamination in blood collection cards poses a challenge for quantifying heavy metals in DBS samples. Here we report a method to remove background contamination from the filter paper prior to blood collection to improve assay precision. Methods: Matched samples of venous blood and finger-stick DBS samples were collected from 82 children ages 1-21. Whole venous blood samples were also applied to pre-cleaned and untreated blood collection cards. All samples were analyzed for As, Pb, Hg, and Cd using inductively coupled plasma mass spectrometry (ICP-MS). Results: Matched venous blood and finger-stick DBS samples from untreated cards were significantly correlated, but with relatively weak R2 values of 0.083, 0.186, 0.498, and 0.022 for As, Cd, Hg, and Pb, respectively. When blood collection cards were decontaminated prior to blood collection the correlations between venous blood and DBS samples were highly significant, with R2 values of 0.66, 0.99, 0.98, and 0.94 for As, Pb, Hg, and Cd, respectively. Conclusions: Standard blood collection cards contain significant and highly variable background levels of heavy metals. Once blood collection cards are treated to remove residual contamination, DBS sampling can be used as a minimally-invasive alternative to venipuncture to estimate exposures to toxic metals.

Water is one of the most valuable natural resource, and most people are aware of the limited supply and importance of water. In Vietnam, public water systems have not been spread to all of the regions yet. Using surface water and groundwater remains the common solution for most residents. However, in some areas, surface water and groundwater is unsuitable for drinking purposes. Rainwater is considered to be a unique alternative for alleviating this problem. This study, therefore, aims at tackling the issues of the water supply encountered at two Vietnam regions, and to propose solutions not only to protect the environment and human livelihood but also for cutting down economic cost.

The impact of a ferronickel smelting plant on the coastal zone has been investigated through metal bioconcentration by two common Mediterranean gastropod species (Patella caerulea and Phorcus turbinatus) collected seasonally together with seawater. P. caerulea presented higher Zn and Fe levels, while Ph. turbinatus higher Mn and Cu ones. The highest concentration of metals was measured in the stations close to the smelting plant in both species. P. caerulea displayed higher seasonal metal levels during autumn and winter as seawater did, while Phorcus displayed higher metal levels in spring. Statistically significant positive correlation was found between the dissolved concentration of Fe and Mn in seawater and the soft tissues in Ph. turbinatus, whereas the same was detected for Zn in P. caerulea. The Cluster analysis based of metals uptake was similar for both species except for Mn and Cu, in P. caerulea and Ph. turbinatus, respectively. The bioaccumulation metals in the two gastropods indicated that the ferronickel smelting plant has a heavily impact on the coastal zone, contaminating the coastal biocenoses with Fe, Mn and Zn. Finally, it seems that Ph. turbinatus reflects better the environmental conditions and could be considered as more efficient bioindicator.

The adsorption capacity of fly ash is much higher than the other adsorbents. The Fly ash was an effective adsorbent especially at high concentration of fluoride. This may be because of the presence of unburnt carbon particles in the fly ash which are known to be very efficient adsorbing materials. The main components of fly ash are silica, alumina, iron oxides, calcium oxide and residual carbon. The presence of unburnt carbon and surface area of ash make it a good candidate for utilization as an inexpensive adsorbent. In this method we use fly ash, generate from Chula. The 100 gm ash is mixed with 1 liter fluoridated water and stirs 45 to 60 minutes then leave it for settle down. After 2 hour this solution filters with G-3 crucible in a filtration unit. The fluoride was analyzed by using ions selective electrode method. This method removes fluoride satisfactory from drinking water but also increases some other parameters of water like alkalinity, chloride, TDS, nitrates etc.so after the view of side effects pre treatment of fly ash have been done with distilled water. The results were found very much satisfactory.

Degradation of coastal ecosystems is an issue of growing concern. Discharges of sewage effluents to sea water is a major contributor to marine pollution. This study examines the biogeochemical effects of sewage pollution on the condition factor and energy reserves of Nerita polita. A total of 135 molluscs were exposed to varying sewage concentrations of between 5%-50%. Physicochemical parameters of the exposure media were characterized using standard techniques. Condition factor of Nerita polita was determined weekly using the Fulton’s index. After the exposure period, the molluscs were sacrificed and energy reserves determined. Increase in sewage pollution resulted in elevation of ammonia (0.01-0.08 mg/L), phosphate (0.05-156 mg/L), nitrates (0.02-1.99 mg/L) and temperature (24.34-25.12oC), while pH (7.75 to 7.29) and dissolved oxygen (5.62-2.38 mg/L) were lowered. There was no correlation between the condition factor of Nerita polita and the sewage pollution. Glucose, lipid and protein concentrations in the mollusc tissues ranged from 29.6-71.3 mg/L, 171-677 mg/L and 338-445 mg/L, respectively, and they decreased along the increasing sewage gradient. Energy reserves in Nerita polita were highest in lipids, followed by proteins and glucose the least and they were affected by the pollution gradient. Findings of this work suggest that energy reserves are sensitive bio indicators but that conditional factor is an unreliable marker to assess acute sewage toxicity. In addition, increase in sewage pollution also leads to a decrease in the water quality and that sewage concentrations above 30% can have profound effects on Nerita polita.

The study of the macro-invertebrates community of Ediba River in Cross River State was carried out from October to December, 2014 using Pollution Tolerance Index (PTI). Macro-invertebrate fauna were sampled with sweeping net using kick sampling methods. Sixteen genera, belonging to nine orders and a total of 289 individuals were encountered. The dominant groups in the order were Oligochaeta (29.1%)>Diptera (24.62%)>Odonata (20.3%), showing insignificant difference between the three stations at p>0.05. Taxa richness was highest in Station 1 (2.985) and least in Station 3 (1.008) showing insignificant differences across station (p>0.05). Evenness ranges from 0.337 to 0.369 showing significant difference across stations (p<0.05). Station 1 had a PTI value of 39 indicating good quality water status, while Stations 2 and Station 3 had PTI values of 6 and 4 respectively indicating poor quality water status. The abundance of pollution tolerance species of the orders, Odonata Zygoptera, Oligochaeta, Diptera and the absence of pollution sensitive species of the orders, Ephemeroptera and Trichoptera in Stations 2 and 3 indicated the poor waters quality, coupled with the low PTI values in both stations, hence need for proper management of the river.

The adsorbent (activated carbon) was prepared from rice hull obtained from communal farmers in Mutoko North (Zimbabwe) by chemical activation using phosphoric acid and was used in the adsorption of aspirin, paracetamol and ibuprofen from hospital effluent. Characterization of the rice hull activated carbon was carried out using the following methods: SEM, XRD, FT- IR. Physical properties such as iodine number, porosity, ash content, moisture content and volatile matter content were also determined. Iodine number was found to be 815.0 ± 2.52 mg/g. FT-IR analysis showed the presence of various functional groups such as C=O, C=C, –OH, and C-H on the surface of the adsorbent whereas SEM micrograph showed that the external surface of the rice hull activated carbon is full of regular cavities. XRD pattern showed broad peaks indicating that rice hull activated carbon produced has amorphous structure. The effect of adsorbent dose, contact time, initial concentration and pH was studied. Adsorption of aspirin fits the Freundlich isotherm, whereas ibuprofen and paracetamol fit the Langmuir isotherm. Kinetic studies showed that adsorption of ibuprofen, aspirin and paracetamol obey pseudo-second order kinetics. Aspirin, paracetamol and ibuprofen were detected in two hospital wastewaters at the concentrations of 0.117 ± 0.0058 mg/L, 0.100 mg/L and 0.010 ± 0.0006 mg/L respectively. The studies showed that pharmaceutical compounds studied can be removed from wastewater using rice hull derived activated carbon.

Cyanobacteria biomass obtained from freshwater bodies is known to contain a large amount of fatty acids. Thus, the current need to produce large amount of lipids for different application has identified cyanobacteria as one of the important sources of fatty acids. However, the production of fatty acids and the characteristics of its composition is a function of nutrients. This paper therefore, reports on the efficient extraction procedures of fatty acids from cyanobacteria biomass using ionic liquid solvent and organic solvent under ultrasonic solid liquid extraction technique and the effect of the variation of iron concentration in the growth media on the fatty acids composition of cyanobacteria biomass. The determination of fatty acids composition was performed using gas chromatography coupled to a time-of-flight mass spectrometer (GCxGC-TOFMS). The obtained fatty acids composition was found to be dominated by tetradecanoic acid (C14:0), hexadecanoic acid (C16:0), 7-hexadecenoic acid (C16:1), pentadecanoic acid (C15:0), 6,9,12,15-octadecatetraenoic acid (C18:4), γ-6,9,12-octadecatrienoic acid (γ-C18:3), 9,12,15-octadecatrienoic acid (C18:3), 9,12-octadecadienoic acid (C18:2), 9-octadecenoic acid (C18:1) and octadecanoic acid (C18:0). Statistically it was proved that the ionic liquid extraction protocol and that of ultrasonic solid liquid extraction by organic solvent were not significantly different. It was also revealed that the total amount of fatty acids in cultured cyanobacteria increased with decrease in iron concentration in the growth medium.

Treated water effluent from Phakalane waste water secondary maturation ponds in Gaborone City (Botswana) enters the Limpopo River via Notwane River. Effluent samples from these ponds were collected and investigated using molecular and analytical methods to determine presence of mcy genes and microcystins (MCs), respectively. It was observed that, potentially toxic algal blooms were present in this effluent and therefore algal toxins. Using Polymerase Chain Reaction (PCR) method; cyanobacterial 16S-rRNA and mcyA, -B, -C, -D, -E and -G genes were amplified and PCR products separated by gel electrophoresis and visualized after ethidium bromide staining. DNA sequence for mcyA gene was obtained using PCR products from a newly designed primer pair for the amplification of mcyA gene. BLAST results of the obtained DNA sequence were evaluated and aligned to NCBI database for species identification. The alignment gave the highest similarity (100%) in nucleotide sequence that was aligned to the DNA sequence of a toxigenic M. novacekii T20-3 based on the published data. Microcystin-RR, -YR, -LR and -WR were chromatographed, identified and quantified from M. novacekii T20-3 cell extracts using LC-ESI-MS technique after liquid-partitioning (LP) and solid-phase extraction (SPE) steps complementing PCR findings. Higher quantities of MC-RR, -LR and YR: 53.620 ± 0.063, 12.114 ± 0.024 and 5.280 ± 0.035 μg/g DW were observed, respectively.