Chlorpyrifos (CPF) is an organophosphorus insecticide that has gained significant attention cue to the reported toxicity associated with developmental exposure. While the canonical mechanism of toxicity of CPF involves the inhibition of brain acetylcholinesterase (AChE), we have reported that exposure of juvenile rats to levels of CPF that do not yield any inhibition of brain AChE results in neurobehavioral alterations at later ages. However, it is unclear what effect exposure to these low levels of CPF has on blood esterase activities which are frequently used not only as biomarkers of exposure but also to set exposure levels in risk assessment. To determine this, male and female rat pups were exposed orally from postnatal day 10 to 16 to either corn oil (vehicle) or 0.5, 0.75, or 1.0 mg/kg CPF. At 12 h after the final exposure, serum cholinesterase (ChE), butyrylcholinesterase (BChE), and carboxylesterase (CES), and red blood cell (RBC) and brain AChE activities were determined. There were no differences between sexes in either the controls or individual treatments for all enzymes. Only the highest dosage of 1.0 mg/kg CPF yielded significant brain AChE inhibition (22-24%) but all dosages significantly inhibited the blood esterases with inhibition being highest with serum CES (65-85%) followed by serum BChE (57-76%), RBC AChE (35-65%), and then serum ChE (16-32%). Our data verify that blood esterases are inhibited at dosages of CPF that alter neurobehavioral performance in the absence of effects on brain AChE activity.

International Journal of Scientific Research in Environmental Science and Toxicology volume5-issue1-ijsret contains the reinventing research ideas into the articles belonging to the present time, and scheduled for publication in a future issue of the journal. Readers can cite these articles with proper referencing.

The transfer of two insecticides (acetamiprid and chlorpyrifos) from cotton fields to a nearby water reservoir together with the ecotoxicological risks involved for this receiving environment were assessed by measuring their concentrations in runoff water and sediment samples collected both at the exit of the crop plots and in the reservoir after treatment. The multi-residue method by UPLC-MS/MS was used to determine the concentration of the different active substances in the collected samples. The results obtained indicate that acetamiprid and chlorpyrifos are almost always present regardless of the treatment period. The physico-chemical properties (solubility in water and adsorption to soil particles) explain a difference in behaviour between acetamiprid, present mainly in water, and chlorpyrifos, more concentrated in sediments. Calculations show that 0.005% of the acetamiprid applied in the basin around Gambanè flows to the reservoir, compared to 0.0003% of the chlorpyrifos applied. Depending on the sampling dates, the average runoff quantities for acetamiprid vary from 0.002 to 0.156 g/ha over 96 g/ha and from 0.001 to 0.039 g/ha for chlorpyrifos. The study shows that the transfer by runoff from the fields is relatively fast but is nevertheless influenced by rainfall, the distance of the fields to the reservoir, the slope and the characteristics of the environment. At the concentrations of acetamiprid observed in this receiving environment, the ecotoxicological risk would be negligible (Environmental Risk Index = 4) for aquatic organisms, earthworms and birds. However, concentrations of chlorpyrifos in the environment could be harmful to these organisms (Environmental Risk Index = 272). The aquatic ecosystem in this area is therefore exposed to the harmful effects of these active substances. Key words: acetamiprid; chlorpyrifos; UPLC-MS/MS; cotton

Diazinon is a widely used household and agricultural pesticide that accumulates in the aquatic environment and adversely affects non-target organisms such as mammals, birds, and fish. Sub-lethal pesticide levels occur in natural waters, and can impact the health, physiology and fitness of fish populations. This study was conducted to assess the effects of chronic, sub-lethal diazinon exposure to skin, liver, kidney, spleen, heart, gut, intestine, and gas bladder tissues of alligator gar, Atractosteus spatula. In two studies, gar were exposed to sub-lethal concentrations of 0.01, and 0.1 mg/L diazinon for 15 and 30 day periods. Skin, gills, liver, and kidney of exposed fish demonstrated remarkable microscopic lesions. These changes included skin lesions in the head and body, which started as white spots and progressed into deep ulcerations, hepatic vacuolation, swollen hepatocytes, steatosis, aggregation of macrophages, necrosis, and hepatic fibrosis. Gill tissues demonstrated epithelial hyperplasia in the secondary lamellae. Vacuolar degeneration was also present in the hematopoietic tissues of the kidney. Lesion occurrence and severity were correlated to increased diazinon dose and exposure time. Our findings revealed the harmful effects of chronic, sub-lethal diazinon exposure on alligator gar, and suggest other aquatic organisms may also be affected by sub-lethal concentrations of pollutants in their environment.

Perchlorate, a manufactured and naturally occurring chemical, was first detected in drinking water supplies in California in the 1980s. In the 1990s, perchlorate contamination (in the parts-per-billion range) was detected in drinking water supplies across the U.S. EPA began evaluating perchlorate for regulation in drinking water in 1998 and has spent 21 years issuing various proposals and findings on perchlorate, with a proposed (not final) drinking water regulation issued on June 26, 2019. The lack of a drinking water standard has had ramifications, including lack of trust in public drinking water resulting in economic hardship, particularly among Department of Defense personnel and other low-wealth communities, the states setting a patchwork of their own regulations on perchlorate, and lack of monitoring or clean-up of perchlorate in Department of Defense water systems. The reasons for EPA’s two-decade rulemaking process for perchlorate include the process EPA uses to determine regulatory feasibility under the Safe Drinking Water Act and the multi-year scientific review process. Key recommendations for shortening the process include amending the Safe Drinking Water Act and increasing transparency of the rulemaking process. List of Abbreviations: BMDL- Benchmark Dose Level; CCL- Contaminant Candidate List; DOD- Department of Defense; DWEL- Drinking Water Equivalent Level; EPA- Environmental Protection Agency; GAO- General Accountability Office; HRL- Health Reference Level; IRIS- Integrated Risk Information System; LOAEL- Lowest-Observed-Adverse-Effect Level; MCL- Maximum Contaminant Level; MCLG- Maximum Contaminant Level Goal; NOAEL- No-Observed-Adverse-Effect Level; NRC- National Research Council; RfD- Reference Dose; RSC- Relative Source Contribution; SAB-Science Advisory Board; SDWA- Safe Drinking Water Act

This study investigated the glyphosate adsorption by water treatment residual using the method of indirect Chemical Oxygen Demand (COD) in aqueous solution using the electrocoagulation process. The optimum glyphosate removal was obtained with typical operating conditions: initial pH of 5.8, initial herbicide concentration of 100 mg/L, current density 25 mA/cm2, type of electrolyte, and salt concentration of 1 g/L and temperature of 20oC. The results showed that the COD of glyphosate removal were 89.8% by using iron (Fe) electrodes at 40 min, 89.8% by using stainless steel S-S at 60 min, while were 84.8 % by using aluminum Al electrodes at the 80 min. It was found that the data fitted to Freundlich (R2 = 0.964) model. In glyphosate the electrocoagulation process can be described by a pseudo first order with rate constant (0.0059, 0.0052 and 0.005 min- 1) by using Fe, S-S and Al electrodes respectively. The consumption of electrical energy for glyphosate at optimum conditions as follows: (9.999, 13.9 and 19.0619 KWh/m3) using Fe, S-S and Al electrodes respectively. Keywords: Electrocoagulation; Electrodes; Herbicide; Glyphosate; Adsorption; Kinetics

Chlorine is extensively used as a powerful oxidizing agent in the countries surrounding the Arabian Gulf for water treatment and biofouling control. Its usage has been increasing significantly as demand for water grows considerably both in industry and for domestic use. This is due to the fact that it is a well-tested technology, has had a history of long-term worldwide industrial use and is of acceptable cost. While the Arabian Gulf waters support a range of coastal and pelagic marine habitats including mangrove forests, seagrass meadows and coral reefs, marine organisms in these waters are living close to their tolerance limits due to the extreme environmental stressors like temperature and salinity. Anthropogenic stressors such as chlorine may further exacerbate these natural stressors. In seawater, chlorine produces a mixture of hypochlorous acid and hypochlorite ion. These rapidly react with the bromide ion to form a mixture of hypobromous and hypobromite ion. Total residual oxidants formed by chlorination although are short lived and not persistent in seawater, they can be quite toxic. In the present study, toxicity data were obtained from 7 acute toxicity tests and 3 chronic toxicity tests using Arabian Gulf aquatic species from different trophic levels. The study also examined the effect of temperature and developmental stages on toxicity of chlorine. Furthermore, differences in the species sensitivity distribution between native and non-native species were compared. The main finding of the study showed that there was no significant difference between native and non-native species for chlorine toxicity. This would suggest that toxicity data from different geographic region can be used in deriving site- specific ecological risk assessment of chlorine. Keywords: Chlorine; Arabian Gulf; acute toxicity; chronic toxicity; risk assessment; species sensitivity distribution;

International Journal of Scientific Research in Environmental Science and Toxicology volume4-issue1-ijsret contains the reinventing research ideas into the articles belonging to the present time, and scheduled for publication in a future issue of the journal. Readers can cite these articles with proper referencing.

Observations through routine tree surveys and reports by estate managers and residents show an increasing rate of sudden fall of healthy looking trees recently in Shell Petroleum Development Company of Nigeria Residential Area (SPDC RA), thus creating a high potential risk to lives and facility. An earlier survey had suggested that a weakening of the root system due to the presence of mushroom species of a cosmopolitan basidiomycete in the genus Ganoderma may be responsible for the tree falls. Consequently, a team was constituted for an emergency tree hazard hunt exercise using the approved criteria for tree cutting as terms of reference. During the tree hunt exercise, a survey was undertaken with the aim of identifying the mushroom species involved and type of disease, disease symptoms, method of infection/spread, any diagnostic tools for the disease as well as curative and preventive measures for the management of the disease in order to proffer suitable recommendations. Forty-one (41) out of a total of two hundred and seventy-one (271) trees surveyed (15%) were impacted by the mushroom. Disease symptoms include yellowing, necrosis, wilting of the palms fronds and development of a basidiocarp at the tree base. The fungus is soil-borne, spreading from root to root and by migration of airborne basidiospores from basidiocarp. It overwinters in dead woody debris and tree stumps. Some diagnostic tools have been developed both in the laboratory and field for the diagnosis of this disease which include; Calorimetric method using Ethylenediamine-tetraacetic acid, Ganoderma selective media, use of Polyclinal Antibodies (PAbs) and Polymerase Chain Reaction (PCR), Remote Sensing System, application of colour indices using multispectral and thermal camera as well as tomography instrument. The use of trench system, soil mounding, fungicidal treatment and replanting techniques have great potentials in the management of this disease. Periodic checks, routine removal of basidiocarps, geo-referencing and superimposing the impacted trees positions on an existing RA Base map and replanting the cut trees to re-vegetate the environment in phases with seedlings around the camp are recommended. Proper taxonomic study on the Ganoderma species diversity in the RA environment is necessary. Keywords: Shell Petroleum Development Company Residential Area (SPDC RA); Basidiomycete; Basidiocarp; Calorimetric method; Polyclinal Antibodies (PAbs); Polymerase Chain Reaction (PCR); Remote Sensing; Taxonomic study; etc.;

Canal Suez is one of the supreme engineering wonder of the world. The canal is owned and maintained by the Suez Canal Authority (SCA) of Egypt. Suez Canal is connecting Mediterranean and Red Seas and was officially opened on Nov 17, 1869. This maritime wonder took more than 15 years to plan and build. The Canal construction was repeatedly hundred by political disputes, labor shortages and even a deadly cholera outbreak. When finally completed, the 101 NM long waterways permanently transformed international shipping by allowing vessel to skip the long and deceitful transit around the southern tip of Africa. The Suez Canal has enjoyed increased traffic in recent years, with roughly 50 ships passing through its waters every day. However, the canal is still hampered by its narrow width and shallow depth, which are insufficient to accommodate two way traffic from modern tanker ships. In 2014, Egypt’s Suez Canal Authority announced an ambitious plan to deepen the canal and create a new 22-mile lane branching off the main channel. Preliminary work has already begun which Egyptian authorities claim could more than double the canal’s annual revenue by 2023. It is an interesting reviewed paper based both on primary and on secondary information and some critical analysis. Paper describes history, engineering wonders, interesting fact and figure of Suez Canal and excellent ambition of human and present status of one of the maritime success of shipping trade that improving the international maritime business and transportation. Keywords: Canal; Suezmax; Traffic;