Abstract: Pesticides and drugs used in agriculture and veterinary
medicine may end up in aquatic environments and bioaccumulate in
the food chain, thus causing serious problems for fauna and human
health. For determination of the toxic effects of atrazine herbicide on
Caspian kutum, Rutilus frisii kutum larvae, the 96-h LC50 of atrazine
was measured for newly hatched larvae as 18.53 ppm. Toxicity of
atrazine herbicide on Caspian kutum larvae was investigated using
concentrations: 9.25ppm, 4.62 ppm and 2.31 ppm for 7 days.
Comparison of the length, weight and condition factor showed that
no significant differences between atrazine exposed and control
groups. The concentration of Na+, K+, Ca2+, Mg2+ and Cl- in whole
body of larvae in control and atrazine exposure groups were
measured and the results showed that concentrations of all these ions
is higher in atrazine exposure group than control group. It is obvious
from this study that atrazine negatively affects osmoregulation
process and changes ion compositions of the body even at sublethal
concentration and acute exposure but have no effects on growth
parameters of the body.
Abstract: This research presents the first comprehensive survey of congener profiles (7 indicator congeners) of polybrominated diphenyl ethers (PBDEs) in sediment samples covering ten sites in CauBay River, Vietnam. Chemical analyses were carried out in gas chromatography–mass spectrometry (GC–MS) for tri- to hepta- brominated congeners. Results pointed out a non-homogenous contamination of the sediment with ∑7 PBDE values ranging from 8.93 to 25.64ng g−1, reflecting moderate to low contamination closely in conformity to other Asian aquatic environments. The general order of decreasing congener contribution to the total load was: BDE 47 > 99 > 100 > 154, similar to the distribution pattern worldwide. PBDEs had rare risks in the sediment of studied area. However, due to the propensity of PBDEs to accumulate in various compartments of wildlife and human food webs, evaluation of biological tissues should be undertaken as a high priority.
Abstract: These studies have been carried out on the behavior of pesticides in aquatic environments of marshes to monitoring water and sediment. A total of 25 water and 25 sediment samples were collected at five sampling station during April, June and September. 2013 the levels of organochlorine (OCP) pesticide as a case study to find out the extent of pesticide contamination and accumulation, in water was the concentration of OCPs (0.02, 0.066, 0.7, 0.8, 0.072, 0.058) ppb. In sediment was the concentration of OCPs (5.897, 10.987, 0.089, 0.096, 7.897, and 12.389) ppb respectively in DDT, DDE, Chlordane, Heptachlor, Lindane, and Endosulfan. There is a relationship between pesticides and sediment and water with physical properties because the concentrations of pesticide in water and sediment are not always in equilibrium Furthermore, when sediments are smaller, the rate of deposition is slower. There the wetlands of pesticides due to factors of high temperature and evaporation but used in the control of pesticides in water and sediment also there still exist a variety of organochlorine pesticide residues in water and sediments of wetlands.
Abstract: A cross sectional study design and standard
microbiological procedures were used to determine the prevalence
and antimicrobial susceptibility patterns of Escherichia coli,
Salmonella enterica serovar typhimurium and Vibrio cholerae O1
isolated from water and two fish species Rastrineobola argentea and
Oreochromis niloticus collected from fish landing beaches and
markets in the Lake Victoria Basin of western Kenya. Out of 162
samples analyzed, 133 (82.1%) were contaminated, with S.
typhimurium as the most prevalent (49.6%), followed by E. coli
(46.6%), and lastly V. cholerae (2.8%). All the bacteria isolates were
sensitive to ciprofloxacin. E. coli isolates were resistant to ampicillin,
tetracycline, cotrimoxazole, chloramphenical and gentamicin while
S. typhimurium isolates exhibited resistance to ampicillin,
tetracycline, and cotrimoxazole. The V. cholerae O1 isolates were
resistant to tetracycline and ampicillin. The high prevalence of drug
resistant enteric bacteria in water and fish from the study region
needs public health intervention from the local government.
Abstract: Ciprofloxacin (CIP) and Carbamazepine (CBZ), nonbiodegradable pharmaceutical residues, were become emerging pollutants in several aquatic environments. The objectives of this research were to study the possibility to recover these pharmaceuticals residues from pharmaceutical wastewater by increasing the selective adsorption on synthesized functionalized porous silicate, comparing with powdered activated carbon (PAC). Hexagonal mesoporous silicate (HMS), functionalized HMSs (3- aminopropyltriethoxy, 3- mercaptopropyltrimethoxy and noctyldimethyl) were synthesized and characterized physico-chemical characteristics. Obtained adsorption kinetics and isotherms showed that 3-mercaptopropyltrimethoxy functional groups grafted on HMS provided highest CIP and CBZ adsorption capacities; however, it was still lower than that of PAC. The kinetic results were compatible with pseudo-second order. The hydrophobicity and hydrogen bonding might play a key role on the adsorption. Furthermore, the capacities were affected by varying pH values due to the strength of hydrogen bonding between targeted compounds and adsorbents. Electrostatic interaction might not affect the adsorption capacities.
Abstract: The increasing usage of antibiotics in the animal
farming industry is an emerging worldwide problem contributing to
the development of antibiotic resistance. The purpose of this work was
to investigate the prevalence and antibiotic resistance profile of
bacterial isolates collected from aquatic environments and meats in a
peri-urban community in Daejeon, Korea. In an antibacterial
susceptibility test, the bacterial isolates showed a high incidence of
resistance (~ 26.04 %) to cefazolin, tetracycline, gentamycin,
norfloxacin, erythromycin and vancomycin. The results from a test for
multiple antibiotic resistance indicated that the isolates were
displaying an approximately 5-fold increase in the incidence of
multiple antibiotic resistance to combinations of two different
antibiotics compared to combinations of three or more antibiotics.
Most of the isolates showed multi-antibiotic resistance, and the
resistance patterns were similar among the sampling groups.
Sequencing data analysis of 16S rRNA showed that most of the
resistant isolates appeared to be dominated by the classes
Betaproteobacteria and Gammaproteobacteria in the phylum
Proteobacteria.