环境与分析毒理学

Historical and scientific data suggest that neurotoxins may have affected human health and consequently the history of Renaissance Europe. During the Anthropocene, the epoch we now live in, huge quantities of neurotoxins such as mercury, lead and manganese are added to the biosphere. Here we searched for proxies in biological materials such as plants and animal products for anthropogenic enrichment with such toxins. To put our results into geological perspective we also searched for such toxins in ancient materials dated to pre-human occupation of the earth. We examined the metal content in putative proxies for enrichment in fossil plants from the early Paleocene (~64 million years old) in New Mexico and from present-day New Mexico and compared this to similar proxies from Peru, a country with a rich mining history, which continues to this day, where neurotoxins ravaged pre-Hispanic settlers and affects present-day miners. We found proxies for metals in the plants and other biological materials. Sixty four million year old plant samples found in New Mexico contained more neurotoxins such as mercury, lead and manganese than samples from present-day New Mexico. Contemporaneous samples from Lima, Peru, had even more neurotoxins than the pre-human samples. Despite such geochemical and human enrichments the stability of systems over geological times was not affected by neurotoxin additions to the biosphere. Though intoxications have been well-documented in historical personages and in contemporaneous epidemics of poisoning, our findings imply that the addition of neurotoxins to the biosphere over geological time periods has, as yet, no discernible influence on human health.

Cancer is one of the main causes of death in the world. Prolonged exposure to genotoxic chemicals observed is one of the primary causes of cancer. A number of assays exist for detection of genotoxicity in a variety of experimental systems. The Comet assay also known as the single cell gel electrophoresis assay is used to detect DNA damage as an indicator of exposure to geno toxicogical agents. The Comet assay is a broadly used method in human, environmental, and eco genotoxicological studies. The aim of our review is to describe Comet Assay protocol with the advantages and limits and to develop some recent studies in which the authors have used comet test to confirm or reverse agent’s genotoxicity.

Loxoscelism is caused by the bite of a spider belonging to any of the Loxosceles species. We analyse the case of a pregnant woman, 35 weeks into gestation, who was accidentally bitten by a Loxosceles rufescens, in June 2015. She was treated with corticosteroids and antihistamines. After 36 hours of the bite, the patient went to Hospital having felt a lack of foetal movements. Foetal death was diagnosed and the woman was admitted for induction of labour. The autopsy stated as the cause of foetal death to be the presence of umbilical vein thrombosis and sub-funicular placental infarction. We propose that the activation of the thrombosis, in the case of this pregnancy was triggered by events linked directly with the venom of the spider. This venom possesses chemical components sufficient to activate the complement cascade which is closely linked to the coagulation system, and indirectly affected by the inflammation of the allergic response in a previously sensitized patient.

On the edge of petroleum exhausting and dependency, solutions are needed. In this short commentary/opinion an overview of the presence of human being in the have caused, and the solutions that can become a tool to address some of those issues. The biomass concept is discussed and presented as an alternative to producing products to compete with those from fossil sources towards the implementation of biorefineries.

Hyperbilirubinemia (also known as jaundice), caused by the accumulation of unconjugated bilirubin, is one of the most common clinical diagnoses in both premature and term newborns. Owing to the fact that bilirubin is metabolized solely through glucuronidation by UDP-glucuronosyltransferase (UGT) 1A1, it is now known that immaturity of UGT1A1 in combination with overproduction of bilirubin during the developmental stage acts as a bottleneck to bilirubin elimination and predisposes the infant to high TBS levels. While neonatal jaundice is mostly benign, excessively high levels of serum bilirubin in a small percentage of newborns can cause acute or chronic bilirubin-induced neurologic dysfunction (BIND), potentially progressing to acute encephalopathy leading to irreversible brain damage and death. As a series of hereditary UGT1A1 mutations have been identified that are associated with UGT1A1 deficiency, new evidence has verified that developmental expression of UGT1A1 is a tightly controlled event, and both genetic polymorphisms and developmental regulation of UGT1A1 are major contributing factors determining the severity of hyperbilirubinemia and bilirubin-induced neurotoxicity. This review recapitulates the progress that has been made in recent years in understanding etiology and physiopathology of severe hyperbilirubinemia, investigating molecular mechanisms underlying bilirubin-induced encephalopathy, and searching for potential therapies for treating pathologic hyperbilirubinemia. Several animal models have been developed to make it possible to examine bilirubin-induced neurotoxicity from multiple directions. Moreover, environmental factors that may alleviate or worsen the condition of hyperbilirubinemia are discussed.

The three most significant things in our life are air, water, and soil which are essential for life and any imbalance of these three cause a big problem in nature. Soil is one of the most common agents in life and supplies us with all the basic necessities. Portland cement is one of the common types of cement which is used in construction nowadays. But soil can be polluted by cement plants, where cement industries are established. The chemical composition of cement is a mixture of calcium aluminum silicate also, a trace amount of Cd, Pb, Fe, Ti and silica. According to several chemical analyses the area surrounding industries show that the further the area is from the factory, the better as soil pollution decreases. In this research paper, we checked the physiochemical pH, electrical conductivity, nitrate ions, sulphate ions, Lead ions and calcium ions content in soil in the Bazian area. The area is far from the surrounding industries and this shows that the further the area is from the factory, the better as soil pollution decreases. There is positive correlation between the calcium ions and electrical conductivity. There is negative correlation between pH and concentration of lead ions. There is also weak correlation between sulphate and nitrate ions concentrations in soil samples.

The residue levels of organochlorine (OCP) and organophosphorus (OPP) in some dairy products and baby foods samples in Assiut markets Egypt were determined. The concentrations of OCP and OPP were determined in milk powder, plain yoghurt, fruit yoghurt, breakfast cereals, wheat cereal-based baby foods, rice cereal-based baby foods and vegetables and fruit-based baby foods by gas chromatography/mass spectrometry. In dairy products, the highest values of OCP and OPP were 9.346 ± 0.950 μg/kg methoxychlor in fruit yoghurt and 2.282 ± 0.400 μg/kg disulfoton in plain yoghurt, respectively. Propachlor, dieldrin (OCP), chlorpyrifos, and parathion- methyl (OPP) were not detected in any dairy product samples. Maximum amounts of methoxychlor (12.710 ± 0.700 μg/kg) and disulfoton (5.369 ± 0.510 μg/kg) were recorded in vegetables and fruit-based baby foods, and wheat cereal-based baby foods, respectively. The analysis of dairy products and baby foods showed lower pesticides values than the permissible limit set by the European Commission in all products, except methoxychlor (OCP) in vegetables and fruit-based baby foods. The results will help in a scientific assessment of the implications of pesticide residues with regards to human risks in Egypt.

The climate changes that are taking place around the world became a serious environmental problem that should be concerned. Three experiments were performed to imitate conditions of the present climate changes and its effect on Nitzschia inconspicua surviving. The results revealed the high tolerance of Nitzschia inconspicua to increased water temperature. Water acidification and high salinities affected the density of Nitzschia inconspicua negatively. In conclusion, the drastic changes that happen in the environment do not affect Nitzschia inconspicua only but also affect other trophic levels. Therefore, we recommend making many efforts to help getting rid of the global warming and prevent its dramatic effects on the environment.

Background: Arsenic (As) in the groundwater is widely recognised as a global threat to human health. Millions of people from different countries including India are heavily dependent on groundwater containing elevated levels of arsenic for both drinking and irrigation purposes. Bihar and West Bengal located within the Middle-Gangetic plain (MGP), are the two worst arsenic exposed states in India. Today it is estimated that more than 5 million people in the Bihar state are drinking water with arsenic concentration greater than permissible limit of 10 μg/L recommended by World Health Organisation. In the present study, four villages Paghari, Habidih situated under Baheri block and Parri, Bairampur situated under Biraul block of Darbhanga districts of Bihar was taken up for the groundwater arsenic and blood arsenic estimation. The arsenic causing health related problems were also evaluated in the rural population.

Methods: Altogether 48 groundwater samples from Hand Tube Wells (HTWs) of four different villages (12 groundwater samples from each village) were randomly collected for arsenic estimation and 48 blood samples were collected from the subject of the same household for blood arsenic estimation (12 blood samples from each village). Assessment of health related problems due to arsenic poisoning was also carried out in this study.

Results: The highest arsenic concentration in groundwater was found to be 911 μg/L in Paghari village of Baheri block while in blood sample it was 252 μg/L observed from the same household in the Paghari village. The typical arsenicosis symptoms like hyperkeratosis in the palm and sole, melanosis of the skin and few cases of cancer were also reported among the population.

Conclusions: The present study thus, concludes that there was high arsenic concentration in the groundwater of four villages of Darbhanga district. Presence of arsenic in the blood samples indicates as a biomarker of arsenic exposure. Arsenic poisoning has caused severe health related problems in these population. Therefore, a proper strategy is urgently required to mitigate the groundwater arsenic contamination and minimize the severity of the arsenic poisoning in these villages.

The reuse of fused slags obtained by treatment of incineration ash produced during the disposal of city garbage or sewage sludge as building materials such as bricks is attracting attention. In this study, we performed elution tests and investigated the physical properties and metal contents of such materials to establish their safety during use. We examined the physical and chemical characteristics of ten slags, which were produced using various methods. A check of the physical properties showed that there were no problems, and we concluded that reuse is possible. Tests showed that elution of toxic metals was low when water was used as the eluent. However, when acid and alkali were used, metal elution increased. Analysis of the eluates showed that arsenic was not eluted from any of the slags tested, and that high concentrations of manganese were present in all the slags.