Monitoring of pesticides water pollution-The Egyptian River Nile.

BACKGROUND: Persistent organic pollutants represent about 95 % of the industrial sector effluents in Egypt. Contamination of the River Nile water with various pesticides poses a hazardous risk to both human and environmental compartments. Therefore, a large scale monitoring study was carried on pesticides pollution in three geographical main regions along the River Nil water stream, Egypt. METHODS: Organochlorine and organophosphorus pesticides were extracted by liquid-liquid extraction and analyzed by GC-ECD. RESULTS: Organochlorine pesticides mean concentrations along the River Nile water samples were 0.403, 1.081, 1.209, 3.22, and 1.192 µg L-1 for endrin, dieldrin, p, p'-DDD, p, p'-DDT, and p, p'-DDE, respectively. Dieldrin, p, p'-DDT, and p, p'-DDE were above the standard guidelines of the World Health Organization. Detected organophosphorus pesticides were Triazophos (2.601 µg L-1), Quinalphos (1.91 µg L-1), fenitrothion (1.222 µg L-1), Ethoprophos (1.076 µg L-1), chlorpyrifos (0.578 µg L-1), ethion (0.263 µg L-1), Fenamiphos (0.111 µg L-1), and pirimiphos-methyl (0.04 µg L-1). Toxicity characterization of organophosphorus pesticides according to water quality guidelines indicated the hazardous risk of detected chemicals to the public and to the different environmental compartments. The spatial distribution patterns of detected pesticides reflected the reverse relationship between regional temperature and organochlorine pesticides distribution. However, organophosphorus was distributed according to the local inputs of pollutant compounds. CONCLUSIONS: Toxicological and water quality standards data revealed the hazardous risk of detected pesticides in the Egyptian River Nile water to human and aquatic life. Thus, our monitoring data will provide viewpoints by which stricter legislation and regulatory controls can be admitted to avoid River Nile pesticide water pollution.

Veterinary antibiotic resistance, residues, and ecological risks in environmental samples obtained from poultry farms, Egypt.

In Egypt, poultry production constitutes one of the main sources of pollution with veterinary antibiotics (VAs) into the environment. About 80 % of meat production in Egypt is of poultry origin, and the potential environmental risks associated with the use of VAs in these farms have not yet been properly evaluated. Thus, the main purpose of this research was to evaluate the prevalence of antibiotic-resistant enteric key bacteria and the incidence of residual antibiotics in poultry farm environmental samples and to determine whether fertilizing soils with poultry litter from farms potentially brings ecological risks. From December 2011 to September 2012, a total of 225 litter, bird dropping, and water samples were collected from 75 randomly selected boiler poultry farms. A high prevalence of Escherichia coli (n = 179; 79.5 %) in contrast to the low prevalence of Salmonella spp. (n = 7; 3.1 %) was detected. Amongst E. coli isolates, serotypes O142:K86, O125:K70, O91:K, and O119:K69 were the most common. Meanwhile, Salmonella enterica serotypes emek and enteritidis were recovered. The antibiograms using the disc diffusion method revealed significantly more common resistant and multi-resistant isolates in broiler poultry farms. Residues of tetracycline and ciprofloxacin were detected at 2.125 and 1.401 mg kg(-1) mean levels, respectively, in environmental samples contaminated with E. coli-resistant strains by HPLC. The risk evaluations highlighted that tetracycline residues in poultry litter significantly display environmental risks with a hazard quotient value above 1 (1.64). Our study implies that ineffective implementation of veterinary laws which guide and guard against incorrect VA usage may potentially bring health and environmental risks.

Polychlorinated Biphenyls Water Pollution along the River Nile, Egypt.

Ten polychlorinated biphenyl (PCB) congeners were determined in water samples collected along the River Nile using gas chromatography-electron capture detector (GC-ECD). PCB concentrations ranged from 14 to 20 µg/L, which were higher than those reported in previous studies, indicating serious PCB pollution in the River Nile. PCB congener profiles varied depending on the sampling sties. PCB-138 was the predominant congener accounting for more than 18% of total PCBs. The composition of PCB congeners in the water revealed that highly chlorinated PCB technical mixtures such as Aroclor 1254 was the main PCB production historically used in Egypt. An increasing trend in PCB levels from the upper stream to the Nile estuaries was observed. The calculated flux of PCBs indicated that 6.8 tons of PCBs is dumped into the Mediterranean Sea each year from the River Nile. The hazard quotients and carcinogenic risk caused by PCB pollution in the River Nile were above the acceptable level indicating that PCBs in the River Nile water pose adverse health effects for all age groups. Our findings revealed that PCBs possess a serious risk to the Egyptian population that depends mainly on the River Nile as a source of water. Thus, stricter legislation and regulatory controls should be applied to reduce the risk of PCBs in Egypt.

Trace metal levels in water, fish, and sediment from River Nile, Egypt: potential health risks assessment.

The purposes of this study were to describe the impact of metal pollution on the main economic fish species Tilapia nilotica and to assess the potential health risk from consuming this contaminated fish in Egypt. Trace metals, including Ag, Al, Cd, Bo, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, St, V, Zn, and As, were determined in water, Tilapia nilotica, and sediments from the River Nile, Domiate branch, Egypt. Metal concentrations in fish of Al, Cd, Co, Fe, Mn, Pb, V, and Zn (mg/kg dry weight [dw]) and concentrations in sediment of Cd, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn (mg/kg dw) were above the International Atomic Energy Agency (IAEA-407) levels. However, trace metals in river water were still at permissible levels for Egyptian standards. The hazard index (HI) of estimated metal mixtures for intake of Tilapia nilotica (23.37) demonstrated that intake resulted in higher noncarcinogenic risk. In conclusion, the overall problem of metal contamination in fish collected from the River Nile was more serious than postulated to occur in an industrialized and densely populated area. In the light of known risks to public health, environmental protection laws are needed in Egypt.