Allium cepa derived EROD as a potential biomarker for the presence of certain pesticides in water

Allium cepa root length inhibition test is a well recommended bioassay for the evaluation of the toxicity of various polluted waters. The utility of EROD (7-ethoxy resorufin O-deethylase) as a potential biomarker of pesticide pollution was investigated using the Allium cepa system. Onion bulbs exposed to model water samples containing any of the six pesticides viz. 2,4-D, HCB, malathion, carbaryl, DDT and endosulphan were analyzed for EROD activity. The pesticide treatment resulted in the enhanced activity of the enzyme, with carbaryl and HCB causing 63- and 53-fold induction respectively with respect to the control at a dose of 1.2 ppb. The industrial wastewater samples from Ghaziabad city of Northern India resulted in about a 68-fold rise in the EROD activity, whereas the Aligarh samples did not exhibit any change within the statistical limit. These results suggest the presence of the test pesticides in the Ghaziabad sample and their absence in the Aligarh sample. Pesticide analysis in the test water samples by HPLC supported this to a large extent. Presence of cycloheximide in the test system brought down the EROD activity, equal to that of control, suggesting the de novo synthesis of the enzyme following the exposure of Allium cepa to pesticides. These studies suggest that the Allium cepa derived EROD can act as a potential biomarker of certain pesticides since even 1ppb of total/individual pesticides brought about >10-fold induction of EROD. We recommend the assay of EROD in the Allium cepa system as a presumptive test for the detection of these pesticides before using analytical techniques like HPLC.     

Environmental effects of new herbicides for vegetation control in forestry

Environmental fate of and toxicity data for ammonium ethyl carbamoylphosphonate [fosamine ammonium], N-(phosphonomethyl)glycine [glyphosate], and 3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4(1H, 3H)-dione [hexazinone] which appear promising for vegetation control in forestry are reviewed. None of the three herbicides is very persistent in soil, with half-lives reported of about 7–10 days for fosamine ammonium, 8–19 weeks for glyphosate, and 1–6 months for hexazinone, depending on soil type and climatic conditions. Degradation in soil is primarily via microbial routes. Whereas hexazinone is a very mobile herbicide (with mobility dependent on soil type), fosamine ammonium and glyphosate are strongly adsorbed and not readily leached in many soil types. Based on bioassay results, the three herbicides exhibit “very low” to “low” toxicity. Fosamine ammonium is not mutagenic and was not teratogenic when fed to pregnant rats at 10,000 ppm. Data on hexazinone indicate no carcinogenic effect in rats, negative in bacterial and mammalian point mutation assays, and not embryotoxic or teratogenic at up to 5000 ppm in diet of rats. The three herbicides have minimum-to-nil effect on soil microorganisms and exhibit little or no potential for bioaccumulation. Limitations of the available data are discussed and suggestions are made for future studies.     

Release,deposition and elimination of radiocesium (137Cs) in the terrestrial environment

Radionuclide contamination in terrestrial ecosystems has reached a dangerous level. The major artificial radionuclide present in the environment is ¹³⁷Cs, which is released as a result of weapon production related to atomic projects, accidental explosions of nuclear power plants and other sources, such as reactors, evaporation ponds, liquid storage tanks, and burial grounds. The release of potentially hazardous radionuclides (radiocesium) in recent years has provided the opportunity to conduct multidisciplinary studies on their fate and transport. Radiocesium’s high fission yield and ease of detection made it a prime candidate for early radio-ecological investigations. The facility setting provides a diverse background for the improved understanding of various factors that contribute toward the fate and transfer of radionuclides in the terrestrial ecosystem. In this review, we summarize the significant environmental radiocesium transfer factors to determine the damaging effects of radiocesium on terrestrial ecosystem. It has been found that ¹³⁷Cs can trace the transport of other radionuclides that have a high affinity for binding to soil particles (silts and clays). Possible remedial methods are also discussed for contaminated terrestrial systems. This review will serve as a guideline for future studies of the fate and transport of ¹³⁷Cs in terrestrial environments in the wake of the Fukushima Nuclear Power Plant disaster in 2011.     

Metabolic and endocrine effects of bisphenol A exposure in market seller women with polycystic ovary syndrome

Bisphenol A (BPA) is one of the synthetic monomer which can be found in the environment. Limited animal and human studies have demonstrated that BPA alters endocrine and or metabolic functions. The aims of the present study were to evaluate serum BPA level in marketing seller women with polycystic ovary syndrome (PCOS) and hormonal and metabolic effects of this exposure compared to a control paired group. In a case-control study, 62 PCOS women who work as marketing sellers and 62 healthy women with similar jobs were included. The two groups were body mass index (BMI)- and age-matched. Serum samples were analyzed for BPA content, fasting blood sugar (FBS), triglyceride, cholesterol, HDL and LDL levels, thyroid stimulating hormone (TSH) concentration, and LH:FSH ratio. Significant higher serum BPA content (0.48 ± 0.08 vs. 0.16 ± 0.04 ng/ml), triglyceride (103.05 ± 13.10 vs. 91.65 ± 12.52 mg/dl), cholesterol (165.05 ± 10.79 vs. 161.21 ± 10.31 mg/dl) levels and LH:FSH ratio (3.64 ± 0.86 vs. 0.62 ± 0.14) and significant lower TSH concentration (1.56 ± 0.68 vs. 2.15 ± 1.09 IU/ml) were detected in case against control group, respectively (P < 0.05). No significant differences were detected in FBS, LDL, and HDL levels between the two groups. Also, there were no significant associations between serum TSH concentration and BPA level neither in case (P = 0.269) nor in control (P = 0.532) groups. In BPA-exposed PCOS women, BPA level was higher than healthy women and this difference maybe the cause of significant differences in levels of triglyceride, cholesterol, TSH, and LH:FSH ratio. These observations confirm the potential role of BPA in PCOS pathophysiology.     

Biology and management of two important <Emphasis Type="Italic">Conyza</Emphasis> weeds: a global review

Weed management is one of the prime concerns for sustainable crop production. Conyza bonariensis and Conyza canadensis are two of the most problematic, noxious, invasive and widespread weeds in modern-day agriculture. The biology, ecology and interference of C. bonariensis and C. canadensis have been reviewed here to highlight pragmatic management options. Both these species share a unique set of biological features, which enables them to invade and adapt a wide range of environmental conditions. Distinct reproductive biology and an efficient seed dispersal mechanism help these species to spread rapidly. Ability to interfere strongly and to host crop pests makes these two species worst weeds of cropping systems. These weed species cause 28–68 % yield loss in important field crops such as soybean and cotton every year. These weeds are more prevalent in no-till systems and, thus, becoming a major issue in conservation agriculture. Cultural practices such as crop rotations, seed rate manipulation, mulching, inter-row tillage and narrow row spacing may provide an effective control of these species. However, such methods are not feasible and applicable under all types of conditions. Different herbicides also provide a varying degree of control depending on crop, agronomic practices, herbicide dose, application time and season. However, both these species have evolved resistance against multiple herbicides, including glyphosate and paraquat. The use of alternative herbicides and integrated management strategies may provide better control of herbicide-resistant C. bonariensis and C. canadensis. Management plans based on the eco-biological interactions of these species may prove sustainable in the future.     

Suicide bombings: process of care of mass casualties in the developing world

In recent times Pakistan's biggest city, Karachi, has witnessed numerous terrorist attacks. The city does not have an emergency response system and only one of the three public sector hospitals has a trauma centre. We describe the pattern of injuries and management of two terror-related mass casualty incidents involving suicide bombers in a developing nation with limited resources. The first incident occurred in May 2002 with 36 casualties, of whom 13 (36%) died immediately and 11 (30.5%) died at the primary receiving hospitals. The second incident was targeted against the local population in May 2004. The blast resulted in 104 casualties, of which 14 (13.46%) died at the site. All patients had their initial assessment and treatment based on Advanced Trauma and Life Support principles and documented on a trauma form.     

Use of Pseudomonas spp. for the bioremediation of environmental pollutants: a review

Environmental pollution implies any alteration in the surroundings but it is restricted in use especially to mean any deterioration in the physical, chemical, and biological quality of the environment. All types of pollution, directly or indirectly, affect human health. Present scenario of pollution calls for immediate attention towards the remediation and detoxification of these hazardous agents in order to have a healthy living environment. The present communication will deal with the use of naturally occurring microbes capable of bioremediating the major environmental pollutants.     

Neural stem cell-based in vitro bioassay for the assessment of neurotoxic potential of water samples

Intensive agriculture activities, industrialization and growing numbers of wastewater treatment plants along river banks collectively contribute to the elevated levels of neurotoxic pollutants in natural water reservoirs across Europe. We established an in vitro bioassay based upon neural stem cells isolated from the subventricular zone of the postnatal mouse to evaluate the neurotoxic potential of raw wastewater, treated sewage effluent, groundwater and drinking water. The toxic potential of water samples was evaluated employing viability, proliferation, differentiation and migration assays. We found that raw wastewater could reduce the viability and proliferation of neural stem cells, and decreased the neuronal and astrocyte differentiation, neuronal neurite growth, astrocyte growth and cell migration. Treated sewage water also showed inhibitory effects on cell proliferation and migration. Our results indicated that relatively high concentrations of nitrogenous substances, pesticides, mercuric compounds, bisphenol-A, and phthalates, along with some other pollutants in raw wastewater and treated sewage water, might be the reason for the neuroinhibitory effects of these water samples. Our model successfully predicted the neurotoxicity of water samples collected from different sources and also revealed that the incomplete removal of contaminants from wastewater can be problematic for the developing nervous system. The presented data also provides strong evidence that more effective treatments should be used to minimize the contamination of water before release into major water bodies which may be considered as water reservoirs for human usage in the future.     

Using GIS tools to detect the land use/land cover changes during forty years in Lodhran District of Pakistan

Environmental Science and Pollution Research - Land use/land cover (LULC) change has serious implications for environment as LULC is directly related to land degradation over a period of time and...