Toxicologie environnementale et analytique

Most regulatory agencies assume that there is no safe level of exposure to carcinogens but that a threshold, or “safe” exposure level exists for non-carcinogens. However, recent discoveries have cast serious doubt on the validity of this concept. Five examples of non-carcinogens without an apparent threshold (neonicotinoids, dioxin, dieldrin, endocrine disruptors, and sulfhydryl-reactive metals) are presented. It is also clear by now that the threshold model for non-carcinogens may seriously underestimate actual risk. Risk assessments can no longer assume thresholds for non-carcinogens when the shape of the dose-response curve is linear at low concentrations. Risk management of such chemicals should be based on the ALARA principle (“as low as reasonably achievable”).

Karaçomak Dam is main source of drinking water in Kastamonu city (Turkey) for this reason, In this study used Water quality index which provides a single value to express overall quality based on 13 variables that were determined during the period between September 2015 until July 2016. Sampling points chosen as described by first station at intake point of the drinking water supply for Kastamonu city, second station was opposite intake point of the drinking water supply about (449) m along at main dam. The parameters namely Electrical Conductivity (EC), pH, Temperature (T), Dissolved oxygen (DO), Turbidity (TUR), Total hardness (Ha), Total alkalinity, Ammonia nitrogen (NH4-N), Nitrite nitrogen (NO2-N), Nitrate nitrogen (NO3-N), Phosphate (PO4-P), Biochemical oxygen demand (BOD), Chemical oxygen demand (COD) were analyzed according to Standard Methods for the Examination of Water and Wastewater. The resulted WQI shows that (35.5 and 32.4) for sites (S1 and S2) respectively. On the other hand, there was significant temporal variations in water quality index among poor quality to excellent quality whereas that January 2016 showed high level of deterioration at (S1, S2), this may be due to starting the winter 2016 where high contribution from runoff at downstream areas which increase of deterioration body water in the Dam. The results clearly show that Water Quality index (WQI) was useful tool to obtain the right decision and evaluating water quality. In future, evaluation of water quality in Karaçomak dam should be given main priority of using the microbiological parameters with physico-chemical parameters in WQI calculations and to water quality monitoring.

In the current scenario of global change, the impact of anthropogenic stressors is affecting the aquatic ecosystems, especially essential microorganisms such as phytoplankton, driving toward a biodiversity crisis. Classic ecotoxicology studies, focused on the immediate tolerance to pollution, have provide an over simplistic understanding of the long time impact of pollutants on phytoplankton (because of the usual misconception that evolutionary changes can only take place at long-term), inadequate to enable a suitable environmental risk assessment (ERA). Currently, concepts such as predictive ecology and integrating strategies are rising rapidly in prominence with regard to forecasting phytoplankton response to human impact. This review compiles the state of the art of multigenerational and evolutionary experimental studies and the mechanisms that trigger rapid adaptation in phytoplankton to anthropogenic stressors, highlighting the importance of ecology and evolution. Ecological realisms is one of the challenging parts of the stressors hazard, considering the broad phytoplankton diversity and the multifactorial character of the natural ambiances. Field and community experiments contribute to a better discerning of ecology interactions and network relations. Moreover, laboratory experiments exploring evolutionary mechanisms that allow rapid adaptation to contaminants (e.g., fluctuation analysis or ratchet procedures) have proven to be useful linking concentration of pollutants and adaptation strategy. When environmental change exceeds the range of variation that can be coped with by organisms through plasticity, selection processes may occur and evolutionary dynamics take place. Ecology and evolution are necessary to enhance the ERA knowledge and novel experiments may well emerge from the when contemplated as whole.

Two dimensional (2D) cell cultures have been the standard in vitro model for environmental safety research. However, it does not properly mimic in vivo system which hampered cellular proliferation and differentiation over an extended culture time and quickly lost its function. In this study, we constructed a new three dimensional (3D) zebrafish liver cell model that more closely mimics the in vivo micro-environment for pharmaceuticals metabolism studies. The magnetic levitation method was used to maintain the controlled and uniform 3D spheroids. These spheroids were then tested with carbamazepine (CBZ) treatment to determine the applicability of this assay in metabolism study. The results demonstrated that the 3D cell model is more resistant to CBZ over 2D cell culture and in vivo and 3D culture cells are noticeable in CYP1a1 activity and the concentration of carbamazepine-10,11-epoxide (CBZ-EP) than 2D cell culture. This 3D cell culture model will provide useful information toward the development of improved biomimetic organ functions for alternatives to animal testing in environmental contaminants.

The great demand for hair dyes can be seen by the proliferation of hair salons. Their ability to impart temporary or permanent colour change to the hair satisfies the desire of consumers for beauty, fashion, and a look-younger image. para-Phenylenediamine (PPD) is found in more than 1000 hair dye formulations and is the most frequently used permanent hair dye component in Europe, North America, and East Asia. In addition, PPD containing permanent hair dyes account for three-quarters of global use and more than one-third of women use in Europe, North America, and East Asia. However, PPD has been banned in Germany, France and Sweden in the early 1900's as a hair dye component and the hazard of PPD on health has been discussed for the past few decades. PPD containing hair dyes have been associated with cancer and mutagenicity, with supportive evidences from both clinical and laboratory studies. Apart from that, PPD has potential toxicity which includes acute toxicity such as allergic contact dermatitis and subacute toxicity. In this article, we provide comprehensive review on the chemical ingredients of hair dyes, roles of PPD in hair dye, metabolic mechanisms of PPD through in vivo and in vitro studies, and mechanism involvement in the health effect of PPD as evidenced from both clinical and laboratory studies.

In this short communication, we report a novel and inexpensive approach to synthesize Beta-Cyclodextrin functionalized Graphene Oxide (GOCD) which has been fabricated for the adsorption of water soluble organic dyes from aqueous solution. The adsorbent GOCD has been synthesized using facile sonochemical route and accordingly characterized using techniques such FTIR, TGA, RAMAN and TEM respectively. Brilliant green dye (BG), a cationic, water soluble dye, commonly used as green pigment in textile/dye printing technology, is a highly toxic compound and consequently GOCD has been employed for its removal before recyclability of the waste water. The adsorption study of BG onto GOCD is investigated using UV-vis absorption spectroscopy. The exploration established the fact that the as-synthesized material GOCD has appreciable capability in dye removal and therefore possesses significant roles in waste water treatment technology.

Internet retailing is a B2C E-commerce mode that is significantly contributing to China’s economic growth. In fact, online retailing in China has developed so rapidly that as of 2014, the country ranks first globally, accounting for 34% of the world’s Internet retailing market share. Along with its financial windfall, however, Internet shopping also brings with it some serious environmental issues. This article will focus on online shopping packaging garbage, which is an aspect of Internet retailing that has not yet received enough attention from either the Chinese government or Chinese consumers. Approximately 14 billion online shopping parcels were shipped in China in 2014, an increase of 52% over 2013. If this trend continues, the waste generated from these shipments will become a massive environmental problem. Excessive packaging and packaging garbage are not only a huge waste of resources, but they also endanger human health and the ecological environment. Internet retailing is important for developing China’s economy, but the development of the Internet economy should not be made at the expense of the environment. China's regulation and disposal of online shopping packaging waste has important reference values for other countries that are developing an Internet retailing economy.

Celebration and commemoration are what we deem fit to showcase historical values of heroes and important people in the society. These are done through various means such as – street naming, excellent awards, chieftaincy titles, and icons on generally acceptable objects of use like currency, dedicating images and creating artworks. Outdoor sculpture, as an appendage of public art, fits into this scenario. It can be defined as a three-dimensional (3-D) or relief work of art or design created by sculptors, and specifically cited in a restricted or unrestricted open space, it can be small or big, life or above life size, or colossal in size. To critically access the role and effect of weather on outdoor Sculptures in Southwestern Nigeria, we have to define weather or simply imply that this project is the definition of weather on outdoor sculptural pieces which could be simply defined as " The state of atmosphere on a particular space and time as regards various climatic variables such as Rainfall, Temperature and Humidity etc. as they affect outdoor sculptures in the Southwestern part of Nigeria, depending on the type of material used for their execution. Sculptures can be carved, modeled, cast, constructed or assembled in whatever form as they attract attention where they are placed. The effect of weather on these sculptures communicates community values, heighten awareness, question assumptions, and transform a landscape; they can have the power, to transform the images in the area of existence over time. To corroborate this, Ref. [1] posits that ‘we can celebrate our loved ones and heroes, with these images we can as well use these sculptural pieces to celebrate our ideals. She goes further to affirm that after some time, less interest is shown by people toward the care of these sculptures. As good as various outdoor sculptures are in the environment they exist, they face unprecedented threats from the effects of weather, most especially when a few people recognize further responsibility towards their care. Artists as well as Meteorologists understand the abrupt humidity and temperature change or other climatic variables on artworks, over time which affects the outdoor sculptures. Expansion, corrosion and contraction weaken fundamental materials of outdoor sculptures. The uneven "breathing" causes a break in the adhesion between different types of materials used in the formation. The result of these negative tendencies can cause breakages and peeling of materials. Relative humidity, Temperature and Rainfall are considerably most important climatic variable affecting outdoor sculpture in this region. This scenario is not unconnected with DeChillo [2] (ibid) affirmation that “metals tarnish, bronze corrodes, and marble and even resin crack”. This paper therefore identifies and analyzes the various harsh effects of weather on outdoor sculptures in Southwest Nigeria, it also catalogues suggestive ways of ameliorating the effects.

Teleostean fish, Oreochromis niloticus was exposed to almix herbicide under field (8 g/acre) and laboratory (66.67 mg/l) conditions for a period of 30 days. Histological and ultramicroanatomical responses were investigated in stomach and intestine. In stomach, light microscopy displayed damaged Columnar Epithelial Cells (CEC) and mucosal folds, thinning of the top plate and fused mucosal folds under laboratory condition but no such significant alterations were observed except mucus secretion in field study. Electron microscopic observation revealed alterations in epithelial contour, damage in microridge structures and excessive mucin mass over epithelial surface under Scanning Electron Microscopic (SEM) study in both conditions, but the damage was more severe in laboratory study. Transmission Electron Microscopic (TEM) study disclosed severe deformed nucleus and mitochondria, cellular necrosis and severe vacuolation under laboratory study, but comparatively less symptomatic changes were observed in field study. Intestine showed damage in CEC and rupture in intestinal villi in both the conditions under light microscopy, while ultrastructural study showed degenerative changes in CEC and excess mucus secretion in laboratory condition under SEM study. TEM study depicted deformed nucleus and mitochondria, severe vacuolation, and appearance of double layered cell structures in the laboratory condition but no significant alterations were observed under SEM and TEM study in field condition. The present results clearly demonstrated comparatively less pathological lesions under field study than laboratory observations and these responses displayed by the fish species could be considered as bio indicator for evaluating herbicidal toxicosis in aquatic environment.

Post-harvest management of contaminated phytoremediation byproducts for combating the problem of heavy metal contamination is of utmost significance in recent years. Soil fertility is greatly affected by expensive conventional remedial technologies and subsequently causes negative impacts on the ecosystem. Phytoremediation proved to be a cost effective, environment friendly and aesthetically pleasing approach which is most suitable for developing countries. In spite of these benefits phytoremediation technique contributes huge quantities of contaminated materials to the environment and creates further pollution problems. Post-harvest management of these byproducts through advanced techniques like composting and compaction, combustion and gasification, phytomining and pyrolysis is essential. A lot of contaminated biomass is produced during phytoremediation processes, which uses high biomass weeds. So it needs proper disposal and management to restrict the passage of contaminants into the food chain. The high biomass plant selected for phytoremediation should be non-edible, disease resistant and tolerant plants, which can provide renewable energy. Post-harvest management of phytoremediation technique is an alternative for biomass to biofuel conversion. This enhances the practicability of phytoremediation technology. Postharvest strategies are essential with preharvest approaches for developing a sustainable phytoremediation technology.

Nanotechnology is an interesting area of multifaceted research in agricultural perspective. This technology incorporates the manufacturing of material at nano level. Nanoparticles (NPs) have now become an integral part of research because of their unique features like their size, shape and surface reactivity. In agriculture sector engineered nanoparticles (ENPs) i.e., metal NPs, metal oxide NPs and Carbon Nano Tubes (CNTs) etc has been used in the form of nanofertilizers and nanopesticide/ herbicides. Therefore, the appropriate use of nanoparticles could provide a proficient sustainable platform to achieve the food requirement of global massive population. As of the application of nanotechnology to agriculture and food industry is outturn in enhanced crop yield with better food quality as well as safety. Inspite of the significances of nano-material, negative outcomes should also be taken in consideration before applying it on a large scale.

In this study, the environmental effects of suspended particulate matter include accelerated corrosion of metals, as well as damage to paints, sculptures, and soil-exposed surfaces on man-made structures. It can be concluded that among the residential areas. In Jabalpur city at Ranji Basti is showing the high SPM quantity and Chotiline phatak is the high traffic zone with the highest concentration of SPM. It has been found that pollution level caused by the SPM is comparatively high in Badafuhara, In all over the year, Adhartal industrial sector is showing the maximum pursuance of SPM in the city among the three industrial sectors, This indicates that the pollution level is less in the industrial zones of the city as compared with the other major cities/metros, as the industrial zone is not so very well established.

In this work the specific activities of natural radionuclides namely (238U series, 232Th series and 40K) has been measured in collected sedimentary phosphate deposits samples from El-Hamraween, El-Quser and Safaga phosphate mines in Egypt. HPGe γ-spectrometry was used. This study was undertaken to estimate the radiation hazard indices in phosphate mining at the studied mines on their occupational workers, and to establish correlation relationships between the some measured heavy metals such as As, Cd and Pb in blood workers and their concentration in phosphate rock ores. As well as determination the biomarkers in the blood workers such as malondialdehyde (MDA) and superoxide dismutase (SOD). The phosphate mine sample of El-Hamrawein has the lowest activity concentration of 226Ra, 232Th and 40K in compared to the phosphate mine samples of El-Quseir and Safaga (El-Hamraweinheavy metals than young ages. There is a good relation between the concentration of the investigated metals in phosphate mine samples and their concentration in blood of the occupational workers in these mines.

Phytoremediation is described as the treatment of environmental problems through the use of plants that mitigate the same without the need to excavate the contaminated material and dispose it elsewhere. Some plants proved to be popular organism for bio-monitoring to determine and identify the sources of heavy metal soil pollution and their detoxification by phytoextraction techniques. In the present work an attempt has been made to remediate Lead (Pb) and Nickel (Ni) from the polluted soil. Soil and plant (luxuriously growing as hyperaccumulator) samples were collected from the polluted sites to find out the extent of Pb and Ni accumulation in them. We found Saccharum, Brassica juncea, Tamarix and Ricinus as efficient accumulators of heavy metal from the soil. Accumulation of Pd was higher than Ni in soil samples from all the sites. For greenhouse experiment B. juncea was selected for Phytoremediation study. Results of AAS of digested samples of both plants and soils of greenhouse experiments showed that heavy metal content declined in pot soil after plants have been grown and harvested. B. juncea reduced 73.15% Pb and 60.13% Ni from their initial concentration in soil thereby proving itself to be a good accumulator of heavy metals and a remedy for controlling heavy metal soil pollution. Most important in phytoremediation is to use wild plants as accumulators in the greenhouse experiment as it minimizes the chances of biomagnification of heavy metals in food chain.

A double extraction method comprising ultrasound assisted QuEChERS treatment combined with hollow-fiber liquid phase micro extraction was developed for the determination of diphenylamine in various fruit samples using gas chromatography coupled to a single-quadrupole mass spectrometer. Briefly, a known portion of fruit sample underwent an ultrasound assisted QuEChERS treatment. The organic phase resulting from QuEChERS treatment of a fruit sample was diluted 5-fold with pure water followed by a hollow fiber liquid-phase micro extraction procedure for further cleaning and preconcentration. In the late procedure, the analyte was extracted from the diluted sample into a thin layer of (dodecane+10% tri-n-octylphosphine oxide) sustained in the pores of a porous hollow fiber. The analyte was back extracted into acetonitrile located inside the lumen of the hollow fiber. Selected ion monitoring mass spectrometry was used for quantitative determination. The calibration curve was linear over the concentration range of 20-200 µg kg-1. The relative recovery was in the range of 76-108% while, precision varied between 6.4-13.7%. Finally, the applicability of the joint method was tested through analysis of diphenylamine in various fruit samples.

Synthetic chemicals foreign to a particular ecological system and has a biological activity can be called xenobiotic compounds. Xenobiotics include drugs, industrial chemicals, naturally occurring poisons and environmental pollutants. Some microorganisms have the ability of breaking down the xenobiotic compounds partially or entirely. But some xenobiotics are recalcitrant in nature because of various reasons. Some of them cannot be used as substrate by microbes, some cannot transport them due to absence of transporting enzymes and some are in accessible to microbes due to larger structure and insolubility. They can be divided into different groups depending on their chemical composition. Biological and non-biological remediation techniques are the most reliable techniques to degrade these compounds. Bacterial biodegradation used in land filling and composting are most economical methods which uses both the wild type and genetically modified bacterial strains. There are many non-biological techniques which have been grouped under thermal and non-thermal techniques which are suitable for xenobiotic degradation.