Occurrence of pesticides and polychlorinated biphenyls in water of the Nile river at the estuaries of Rosetta and Damiatta branches, north of Delta, Egypt

A study was conducted from summer 1995 to summer 1997 to assess the seasonal occurrence of pesticide residues and other organic contaminants, polychlorinated biphenyls (PCBs), in water at the estuaries of Rosetta and Damiatta branches of the Nile river. The results indicated that organochlorine compounds (OCs) including HCB, lindane, p,p'-DDE, p,p'DDD, p,p'-DDT, aroclor 1254 and aroclor 1260 were present in all the water samples at concentration levels ranging between 0.195-0.240, 0.286-0.352, 0.035-0.067, 0.019-0.033, 0.024-0.031, 0.390-0.70 and 0.166-0.330 microgram/l, respectively. The levels of these compounds were higher in water of Damiatta branch than those found in water of Rosetta branch. Aldrin, dieldrin and endrin were not detected in all water samples. Only 4 compounds from 36 organophosphorus insecticides, fungicides and s-triazine herbicides tested were detected in water samples collected during summer and autumn seasons from Rosetta branch. The concentration levels of these detected compounds, dimethoate, malathion, captan, and ametryne, ranged from 0.011 to 0.340 microgram/l, respectively. Similar compounds during the same seasons as found in water of Rosetta branch were also detected in water of Damiatta branch except ametryne. The levels of the detected compounds (dimethoate, malathion and captan) ranged between 0.030 and 0.330 microgram/l. The levels of detected organophosphorus insecticides, fungicides and s-triazine herbicides were in the order: dimethoate > malathion > captan > ametryne.     

Occurrence of pesticides and polychlorinated biphenyls in water of the Nile river at the estuaries of Rosetta and Damiatta branches,north of delta,Egypt

Abstract

A study was conducted from summer 1995 to summer 1997 to assess the seasonal occurrence of pesticide residues and other organic contaminants, polychlorinated biphenyls (PCBs), in water at the estuaries of Rosetta and Damiatta branches of the Nile river. The results indicated that organochlorine compounds (OCs) including HCB, lindane, p,p‘‐DDE, p,p‘DDD, p,p‘‐DDT, aroclor 1254 and aroclor 1260 were present in all the water samples at concentration levels ranging between 0.195–0.240, 0.286–0.352, 0.035–0.067, 0.019–0.033, 0.024–0.031, 0.390–0.70 and 0.166–0.330 μg/l, respectively. The levels of these compounds were higher in water of Damiatta branch than those found in water of Rosetta branch. Aldrin, dieldrin and endrin were not detected in all water samples. Only 4 compounds from 36 organophosphorus insecticides, fungicides and s‐triazine herbicides tested were detected in water samples collected during summer and autumn seasons from Rosetta branch. The concentration levels of these detected compounds, dimethoate, malathion, captan, and ametryne, ranged from 0.011 to 0.340 μg/l, respectively. Similar compounds during the same seasons as found in water of Rosetta branch were also detected in water of Damiatta branch except ametryne. The levels of the detected compounds (dimethoate, malathion and captan) ranged between 0.030 and 0.330 μg/l. The levels of detected organophosphorus insecticides, fungicides and s‐triazine herbicides were in the order: dimethoate > malathion > captan > ametryne.     

Assessment of natural radioactivity levels in soil samples from some areas in Assiut, Egypt

The natural radioactivity of soil samples from Assiut city, Egypt, was studied. The activity concentrations of 28 samples were measured with a NaI(Tl) detector. The radioactivity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K showed large variations, so the results were classified into two groups (A and B) to facilitate the interpretation of the results. Group A represents samples collected from different locations in Assiut and characterized by low activity concentrations with average values of 46.15?±?9.69, 30.57?±?4.90, and 553.14?±?23.19 for ²²⁶Ra, ²³²Th, and ⁴⁰K, respectively. Group B represents samples mainly collected from the area around Assiut Thermal Power Plant and characterized by very high activity concentrations with average values of 3,803?±?145, 1,782?±?98, and 1,377?±?78 for ²²⁶Ra, ²³²Th, and ⁴⁰K, respectively. In order to evaluate the radiological hazard of the natural radioactivity, the radium equivalent activity (Ra_eq), the absorbed dose rate (D), the annual effective dose rate (E), the external hazard index (H _ex), and the annual gonadal dose equivalent (AGDE) have been calculated and compared with the internationally approved values. For group A, the calculated averages of these parameters are in good agreement with the international recommended values except for the absorbed dose rate and the AGDE values which are slightly higher than the international recommended values. However, for group B, all obtained averages of these parameters are much higher by several orders of magnitude than the international recommended values. The present work provides a background of radioactivity concentrations in the soil of Assiut.     

Risk posed by chlorinated organic compounds in Abu Qir Bay,East Alexandria,Egypt

Introduction  

In Egypt, the picture of threats to humans and the environment from the exposure to organic pollutants is still incomplete. Thus the objectives of this study were to assess the occurrence and distribution of polychlorinated biphenyls (PCBs), organochlorine pesticides, and chlorpyrifos in sediments and mussels of Abu Qir Bay and their risks for environment and human health.     

Remediation of a chlorinated aromatic hydrocarbon in water by photoelectrocatalysis

Photoelectrocatalysis driven by visible light offers a new and potentially powerful technology for the remediation of water contaminated by organo-xenobiotics. In this study, the performance of a visible light-driven photoelectrocatalytic (PEC) batch reactor, applying a tungsten trioxide (WO₃) photoelectrode, to degrade the model pollutant 2,4-dichlorophenol (2,4-DCP) was monitored both by toxicological assessment (biosensing) and chemical analysis. The bacterial biosensor used to assess the presence of toxicity of the parent molecule and its breakdown products was a multicopy plasmid lux-marked E. coli HB101 pUCD607. The bacterial biosensor traced the removal of 2,4-DCP, and in some case, its toxicity response suggests the identification of transient toxic intermediates. The loss of the parent molecule, 2,4-DCP determined by HPLC, corresponded to the recorded photocurrents. Photoelectrocatalysis offers considerable potential for the remediation of chlorinated hydrocarbons, and that the biosensor based toxicity results identified likely compatibility of this technology with conventional, biological wastewater treatment.     

Analysis of short chain chlorinated paraffins in sediment samples from the Czech Republic by short-column GC/ECNI-MS

Top layer sediment samples from the Czech Republic were analyzed to obtain the preliminary information about contamination of the region by chlorinated paraffins. Sediment samples from three locations with different industrial discharges were taken over the period of 2 years. The analysis was performed by short-column gas chromatography-electron capture negative ion mass spectrometry (SCGC/ECNI-MS). Short chain chlorinated paraffin sediment concentrations varied between 24.00 and 45.78 ng g(-1) (dry weight, d.w.) in the Kosetice area, 16.30-180.75 ng g(-1) (dry weight) in the Zlín area and 4.58-21.57 ng g(-1) dry weight in the Beroun area. Highly chlorinated undecanes prevailed in the samples. On the basis of these results, more detailed studies should be conducted to determine the magnitude and extent of chlorinated paraffin contamination in these regions.     

Trends in the levels of some chlorinated hydrocarbon residues in adipose tissue of Canadians

Trends in the levels of hexachlorobenzene, hexachlorocyclohexanes, oxychlordane, t-nonachlor, heptachlor epoxide, dieldrin, DDTs and polychlorinated biphenyls in adipose tissue of the Canadian population were followed from 1969 to 1985. Residues of lindane, dieldrin and p,p'-DDT continuously and significantly (P<0.025) decreased during that time, coinciding with restrictions on their use. Other residues also decreased significantly between 1969 and 1985, although not always continuously, while t-nonachlor levels did not change significantly since 1972. In general no consistent and/or significant differences were observed between the sexes, but in some instances differences were found for a particular residue in a given year. Three arbitrarily chosen age groups (0-25; 26-50 and > or =51 years) showed a downward trend in residue levels with time. The results of the surveys also indicate an increase in adipose tissue burden of chlorinated hydrocarbons with age, but this increase became apparently less significant with increasing age.     

GC/MS analysis of polynuclear aromatic hydrocarbons in sediment samples from the Niger Delta region

Thirteen sediment samples from different locations in the Niger Delta region of Nigeria were analyzed for the presence of 16 polynuclear aromatic hydrocarbons (PAHs) via gas chromatography/mass spectrometry. The specific target compounds for this study included naphthalene, acenaphthylene, acenaphthene, flourene, phenanthrene, anthracene, flouranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]flouranthene, benzo[a]pyrene, benzo[ghi]perylene, dibenz[a,h]anthracene, and indeno[1,2,3-cd]pyrene. Four isotopically labeled polynuclear aromatic hydrocarbons (acanaphthene-d10, phenanthrene-d10, chrysene-d12 and perylene-d12) were used for internal standardization. All 16 PAHs were found in most of the thirteen samples with concentration ranging from 0.1 microg/kg to 28 microg/kg. It was also found that the 5 and 6-ring PAHs were present in higher concentrations than all the other compounds, indicating their high resistance to microbial degradation.     

Perfluorinated compounds in water, sediment, soil and biota from estuarine and coastal areas of Korea

Soil, sediment, water, and biota collected from the western coast of Korea were analyzed to determine occurrence and sources of perfluorinated compounds (PFCs). PFCs were significantly concentrations of PFCs were measured in some water and biological samples, while concentrations of PFCs in soils and sediments were relatively low. The most widely detected compound was found to be perfluorooctanesulfonate (PFOS), with a maximum concentration in water of 450 ng/L and in fish of 612 ng/g, dw. PFOS concentrations in water and biota were both less than those thought to cause toxicity. However, in both cases concentrations were within a factor of 10 of the toxicity threshold concentration. Concentrations of PFCs were significantly greater downstream than those upstream on the same river, suggesting point sources. Overall, the detection of PFCs at relatively great concentrations in various environmental matrixes from this region of Korea suggests that further studies characterizing PFCs and their potential risk to both humans and wildlife are needed.     

Trace metal levels in freshwater fish, sediment and water

The trace metal concentrations in water, sediment and aquatic organisms, such as fish, could indicate the level and tendency of the pollution. This is important not only for the protection of the environment, but for evaluation of the quality of fish meat either captured from natural waters or cultured in fishponds. The total trace metal concentrations in samples of fish from different regions of Hungary and from different species have been determined by using an X-ray fluorescence technique (EDXRF). Water, sediment and fish samples from fishpond systems with different feeding and stocking has also been analyzed. In the case of zinc contents, differences have been traced between the cultured and wild common carp. In the case of common carp reared under different feeding conditions, differences were also observed in the zinc concentration. The retention of the trace metals in the fish has been studied by measuring the levels in sediment, water and feed. The different retention can be explained by the different availability of zinc in the applied feeds, which can be related to the presence of different metal species in the feeds.     

Evaluation of modifications of the simple spectrofluorometry method for estimating petroleum hydrocarbon levels in fresh and waste water samples

The monitoring of petroleum hydrocarbons in the water environment is very often performed using complicated methods. There are many difficulties encountered in analyzing a long number of samples in the monitoring programme. In such cases, a simpler though less precise and specific technique using inexpensive equipment to monitor a large number of water samples, might be more desirable.

This idea was realized in the assessment of the state of pollution of the Mediterranean Sea by petroleum hydrocarbons where the pollution of sea water with oil (dissolved and/or dispersed in sea water) was measured by spectrofluorometry. The paper describes an analytical evaluation of three modifications of simple the spectrofluorometry method, applied on numerous river and waste water samples collected from various areas of Croatia.     

Comparative study on the toxic effects of some heavy metals on the Nile Tilapia,Oreochromis niloticus,in the Middle Delta,Egypt

Heavy metals are the most dangerous hazards affecting aquatic biota in Egypt specially the Nile Tilapia, Oreochromis niloticus, which is an important species in commercial fisheries. Some areas were not fully studied to screen the hazards that may affect this economic fish. Therefore, the present study aimed to evaluate the potential hazards of heavy metals on O. niloticus in Al-Gharbiya Governorate in the Middle delta of Egypt. Water and fish samples were collected from Al-Qased canal, Kafr El-Zayaat Nile, El-Maash canal in Al-Gharbiya Governorate plus a reference site which is a fish farm at the Faculty of Agriculture, Damietta University, Damitta Governorate, Egypt. The results showed a significant increase (p?<?0.05) in the lead, zinc, magnesium, manganese, and copper levels while showed a significant decrease (p?<?0.05) in the iron level in the water from all the investigated areas. Cadmium level was significantly high (p < 0.05) in Kafr El-Zayaat Nile and EL-Maash canal only. These metals were also accumulated in the fish livers and gills. Consequently, ALT and AST activities and creatinine level were significantly (p?<?0.05) high in all the investigated areas. Histopathological examination revealed cytoplasmic and nuclear degeneration in the hepatocytes in all the investigated areas. Renal glomeruli and Bowman’s capsule were not completely intact in Al-Qased and El-Maash canals while conspicuous shrinkage of the glomeruli was determined in Kafr El-Zayaat Nile. Furthermore, slight damage in the secondary lamellae was detected in the gill from Al-Qased canal while in the other areas appeared vacuolated or destructed. Finally, spleen sections of fish from different sites showed the absence of melanin pigments and some vacuoles. In conclusion, the Nile Tilapia, Oreochromis niloticus, is affected by the toxic effects of the heavy metals in Al-Gharbiya Governorate in Egypt and this gives an alarm and should be taken into consideration.

     

Method development and application for triazine herbicides analysis in water,soil and sediment samples from KwaZulu-Natal

Penoxsulam is a triazolopyrimidine sulfonamide group of rice herbicide. The phototransformation of penoxsulam was studied under UV light (λ_max ≥ 290 nm) and sunlight in aqueous methanol and acetonitrile solvent system using TiO₂ as sensitizer. The rate of photodegradation of penoxsulam in different solvent systems followed first-order kinetics and calculated half-lives was found to be in the range of 51.89–73.41 h and 62.70–97.09 h for UV light and sunlight respectively in the presence or absence of sensitizer. From this study, a total of six photoproducts were identified and characterized on the basis of Q-Tof micromass spectral data. The plausible mechanism of phototransformation involved were hydrolysis, photo oxidation of the sulfonamide group, breaking of sulfonamide bond, loss of amino and sulfonic acid group.     

Metals in a northern Nile Delta lake: water,suspended particulates,sediments, and biota

Lake Edku is one of the important fishing areas in the Nile Delta. It is exposed to different quantities of serious pollutants in particular metals. To overall appraise the risk and status of metals in the lake, a comprehensive study of total concentrations of cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), and zinc (Zn) in sediments and spatial-temporal variations of these metals in the dissolved and suspended particulates, and some tissues of Tilapias niloticus, was conducted from ten sampling sites during 2016. Results showed that none of the investigated metals exceeded the limits considered as hazardous for aquatic life in water. The highest concentrations of Cd, Cu, Ni, and Zn were observed in suspended particulate matter, which may precipitate on the surface of the sediments. Potential ecological risk analysis of the majority of the investigated metals in the sediment indicated that Lake Edku posed a low ecological risk. The estimated values of all metals in tissues of Tilapia niloticus were below the international permissible limits. Moreover, the potential risk of metals to human via the consumption of Tilapia niloticus was estimated using the weekly intake levels, which was lower than the WHO’s safe provisional tolerant weekly intake levels. These results prove the importance of performing measurements of contaminants in various compartments of Lake Ecosystem including sediment, biota, and suspended particulate matter for proper management.     

Reaction rates and intermediates of chlorinated organic compounds in water and soil

Degradation reactions of thirteen chlorinated organic compounds were investigated in a water system and a water-soil system. Three compounds were degraded following the first order rate equation regardless of pH, and five compounds were degraded following the second order rate equation with a concentration of hydroxide ion in alkaline solution.The reaction rate constants and the activation energies of the reactions were obtained, and the intermediates were determined quantitatively for the eight compounds.From the result of the degradation of 1,1,1-trichloroethane in the water-soil system, it was found that 1,1,1 trichloroethane did not react on the soil surface and only reacted in the water phase.     

Influence of oil contamination levels on hydrocarbon biodegradation in sandy sediment

The influence of oil concentration on hydrocarbon biodegradation in a sandy sediment was studied in polyvinyl chloride reactors (0.45 x 0.28 x 0.31 m) containing 76.8 kg of beach sand in natura, where the upper layer was artificially contaminated with petroleum. The oil-degrading microorganisms used consisted of a mixed culture named ND, obtained from landfarming and associated with indigenous microorganisms. On the 28th day of the process, the degradation in reactors containing sandy sediment contaminated with light Arabian oil and presenting an initial oil content of 14, 21 or 28 g kg-1 reached the following levels (%): 33.7, 32.9 and 28.9 for oil and grease; up to 88.3, 35.3 and 13.0 for C14-C26 n-alkanes; and 100, 61.3 and 59.4 for pristane, respectively. Phytane removal (37.1%) was only detected in the reactor contaminated with the lowest oil concentration studied. These results, together with the expressive bacterial growth observed (from 10(6) to 10(11) cfu g-1) give strong support to the argument that biodegradation was the dominant component of the remediation process. Susceptibility to biodegradation was inversely proportional to increasing oil contamination. The degradation of branched alkane: pristane was not repressed by the presence of n-alkanes.     

Sterols in sediment samples from Venice Lagoon, Italy

Sterols of different origin were analysed in sediment samples collected in the Venice Lagoon. The purpose of the study was to investigate the degree of sewage contamination within the Lagoon using fecal sterols (coprostanol, epicoprostanol and coprostanone) and to analyse the pattern of the sterols to plot the origin of the organic matter.

Sedimentary coprostanol at Canal Grande within the city of Venice was more than one order of magnitude higher than other stations in the Lagoon and two orders higher than in a sediment sample collected in the open sea. The cholesterol/coprostanol ratio, like the percentage of coprostanol in total sterols at this sample site was very similar to values in sewage sludge. The different pattern of sterols at station 2 which had the largest amount of total sterol indicates a difference in the origin of the organic material. Nevertheless the sterols used as tracer of terrestrial vascular plants did not show any particular trend at this station, receiving fresh water inputs. (3-Sitosterol and cholestanol reached the highest levels at the station within the Chioggia basin.     

Occurrence of organotin compounds in water and sediment in Canada

Water and sediment samples from 265 locations across Canada were analyzed for butyltin and methyltin species, and inorganic tin. In 10% of the water samples the highly toxic tributyltin species was found at concentrations which could cause growth retardation upon chronic exposure to a sensitive organism, rainbow trout yolk sac fry. High concentrations of tributyltin were found in some sediments (up to 10 mg Sn/kg dry weight), but the biological availability of sediment-associated tributyltin is unknown. Tributyltin was mainly found in areas of heavy boating and shipping traffic, which is consistent with its use as an antifouling agent in some paints for boats, ships and docks. The methyltin species were found much less frequently in water and sediment than tributyltin and its degradation products.     

Occurrence and partition of perfluorinated compounds in water and sediment from Liao River and Taihu Lake, China

The concentrations of four perfluorinated sulfonate acids (PFSAs) and 10 perfluorinated carboxylate acids (PFCAs) were measured in water and sediment samples from Liao River and Taihu Lake, China. In the water samples from Taihu Lake, PFOA and PFOS were the most detected perfluorinated compounds (PFCs); in Liao River, PFHxS was the predominant PFC followed by PFOA, while PFOS was only detected in two of the samples. This suggests that different PFC products are used in the two regions. PFOS and PFOA in both watersheds are at similar level as in the rivers of Japan, but significantly lower than in Great Lakes. The contributions of PFOS and long chain PFCAs in sediments were much higher than in water samples of both watersheds, indicating preferential partition of these PFCs in sediment. The concentrations of PFOS and PFOA were three orders of magnitude of lower than that of polycyclic aromatic hydrocarbons in the same sediments. The average sediment-water partition coefficients (log K_oc) of PFHxS, PFOS and PFOA were determined to be 2.16, 2.88 and 2.28 respectively.     

Screening 31 endocrine-disrupting pesticides in water and surface sediment samples from Beijing Guanting reservoir

For screening 31 potential or suspected endocrine-disrupting pesticides in water and surface sediments, a multiresidue analysis method based on gas chromatography with electron capture detection (GC/ECD) was developed. Solid phase extraction (SPE) technology with Oasis^® HLB cartridge was also applied in sample extraction. The relevant mean recoveries were 70–103% and 71–103% for water and sediment, respectively. Relative standard deviations (RSD) are 2.0–7.0%, 4.0–8.0% for water and sediment, respectively. Thirty one pesticides (-HCH, β-HCH, γ-HCH, δ-HCH, hexachlorobenzene (HCB), aldrin, heptachlor, endosulfan I & II, p,p′-DDD, o,p′-DDT, p,p′-DDT, p,p′-DDE, endrin aldehyde, endosulfan sulphate, methoxychlor, hepachlor epoxide, -chlordane, γ-chlordane, dieldrin, endrin, dicofol, acetochlor, alachlor, metolachlor, chlorpyriphos, nitrofen, trifluralin, cypermethrin, fenvalerate, deltamethrin) in water and surface sediment samples from Beijing Guanting reservoir were analyzed. Concentrations of pesticides ranged from 7.59 to 36.0 ng g⁻¹ on a dry wt. basis for sediment samples, from 279.3 to 2740 ng l⁻¹ for pore waters and from 48.8 to 890 ng l⁻¹ for water samples, respectively, with a mean concentration of 10.7 ng g⁻¹ in sediment, 735 ng l⁻¹ in pore water and 295 ng l⁻¹ in water, respectively. The data obtained provides information on the levels and sources of endocrine-disrupting pesticides in Guanting reservoir. These results underscore the need to improved environmental protection measures in order to reduce the exposure of the population and aquatic biota to these endocrine-disrupting compounds.