Toxicología ambiental y analítica

This research was conducted to determine the productivity, vitamins and heavy metals concentration of Pleurotus ostreatus (Jacq: Fr) Kumm. friut bodies cultivated on different wood logs. Pure mycelium culture of P. ostreatus was aseptically multiplied by grain-to-grain transfer using sorghum grains. Fully colonized spawn was used to inoculate Mangifera indica, Dacryodes edulis and Treculia africana logs and incubated in the dark at 27°C ± 2 M. Fruit body primordia were first observed in D. edulis followed by T. africana and lastly on M. indica logs after 11, 13 and 15 days respectively. M. indica log substrate gave the highest (245.8100 g/kg) yield of P. ostreatus fruit bodies among other log substrates. Vitamin contents were significantly highest in P. ostreatus cultivated on D. edulis logs while P. ostreatus cultivated on all the log substrates accumulated copper more than every other heavy metals analyzed. Both vitamins and heavy metals contents of P. ostreatus across various log substrates were significantly different p<0.05. Cultivation of P. ostreatus on M. indica logs especially before they are used for firewood will help boost food provision.

To study the characteristic of inorganic elements, carbon species, PAHs of exposure and elements health risk to PM2.5 for urban cyclists in Tianjin. Exposure to PM2.5 samples in cycling were collected during Summer in Tianjin. The non-carcinogenic risk and carcinogenic risk of personal exposure heavy metal in PM2.5 were discussed. The average personal exposure mass concentration of PM2.5 is 340.63 μg/m3 in the weekday, 281.25 μg/m3 at the weekend for cyclists. Enrichment factor analysis showed that Pb, Zn, Ni, and Cu exhibited heavy or extreme contamination, indicating the influence of anthropogenic sources, but K, Ca, Mg, Mn and Fe were minimally enriched and were mainly influenced by crustal sources or lesser anthropogenic sources. The average SOC is 23.33 μg/m3. The proportion of SOC is 34.78% in OC. PAHs in PM2.5, 2-ring and 3-ring compounds were predominant with NAP, PHE and ACY accounting for 25%, 48% and 9% of PAHs for the personal exposure for cyclist, respectively. For non-carcinogenic effects, Hazard index values for all studied metals were lower than the safe level of 1 for cyclists. The carcinogenic risk for Cr and Ni were all below the acceptable level (10-4~10-6). The present study demonstrated the elements health risk in Urban Cyclists. The study may provide a scientific basis for protecting cyclists’s health and safety.

Liquefied Petroleum Gas (LPG) is widely used as fuel at homes and in vehicles in the compressed gas cylinders. Previously, some reports of toxicity with gas inhalation causing different symptoms from a simple headache and dizziness to coma and death had been published. In this report, the states of 2 children, a 5-year-old girl and her 2-yearold brother, who developed convulsion and reduced level of consciousness following playing with and opening the gas valve of a portable cooking gas stove at the kitchen, are explained.

A flow injection hydride generation atomic (FI-HG-AAS) method was developed for determination of arsenic in certified reference materials after open wet digestion of samples. Steps of the method were optimized and analytical as well as statistical parameters of the method were determined (Detection limit 1 μg/kg-1, Quantification limit 3 μg/kg-1). Accuracy of the method was evaluated using GBW10043 (Rice), GBW100052 (Green tea), T0770 (soya flour), NCS-ZC 73013 (Spinach), NCS-ZC 73015 (Milk powder) reference materials.

The present study explored the removal of toxic Cr(VI) ions by MnO2 coated polyaniline nanofibers (MPNF) adsorbent by batch mode technique. The MnO2 coated polyaniline nanofibers were synthesized by in-situ oxidative polymerization of polyaniline by rapid mixing technique and were employed for the removal of Cr(VI) ions from aqueous solution. The synthesized adsorbent was characterized by various techniques to elucidate the structure, composition, and morphology. The effects of pH, initial Cr(VI) concentration, adsorbent dose, temperature and operating time on adsorption were investigated. The maximum adsorption removal efficiency was observed at low pH i.e., 1.0. Spectrophotometric method was used to examine the Cr(VI) concentration in the filtrate after batch adsorption studies. The equilibrium adsorption capacity and adsorption kinetics followed Freundlich isotherm and pseudo-second-order respectively, with a capacity of 39.3 mg/g. The thermodynamic study parameters like: ΔH°, ΔS° and ΔG° revealed that the adsorption process is spontaneous and endothermic at high temperature.

Natural and anthropogenic factors affect soil pollution which significantly reduces environmental quality. In this study, six hazardous elements namely Chromium (Cr), Nickel (Ni), Arsenic (As), Cadmium (Cd) and Lead (Pb), in 12 different sampling sites around brick kiln vicinity from Bangladesh were assessed. The ranges of Cr, Ni, Cu, As, Cd and Pb in studied soils were 0.77–21.71, 4.74– 27.67, 3.08–38.56, 2.51–28.44, 1.03–8.06 and 2.23–18.31 mg/kg, respectively. Presence of these hazardous elements in soils is indicating a potential risk to the environment. Certain indices, including the enrichment factor (EF), pollution load index (PLI) and contamination factor (Ci f), geoaccumulation index (Igeo), toxic unit analysis and principal component analysis (PCA) were used to assess the ecological risk posed by hazardous elements in soils. The Ci f values of As (15.34) and Cd (37.89) revealed that the examined soils were strongly impacted by As and Cd where Pollution load index in As (1.01) and Cd (2.61) indicating progressive deterioration of soil due to metal contamination. In view of the above results, soils from all sampling sites showed considerable to very high potential ecological risk.

Objective: In order to explore the impacts of environmental hormones (EHs) on plants, the relationship between EHs pollutants and Spinacia oleracea HSP70-9 expression was studied in this paper. The researchers studying HSP70 have primarily investigated high temperature stress, low temperature stress, water stress and other environmental factors, such as heavy metals, wind stress, salt stress. However, as a type of environmental pollutant, EHs may affect the growth and development of plants.
Methods: Two typical EHs, PAEs (phthalates esters) and BPA (bisphenol A), were selected for the study. RT-qPCR was used to study HSP70-9 expression at the transcriptional level under single and combined pollution conditions in spinach seedlings.
Results: The result of the present study showed that, the spinach HSP70-9 expression is downregulated with single and combined treatments of EHs.
Conclusion: The conclusion is that BPA and PAEs had certain effects on the expression of HSP70-9 in spinach.

The study was conducted in Gozamen district of East Gojam Zone of the Amhara region to assess the major feed resources, the grazing land condition, the floristic composition, and biomass yields of herbaceous species to generate baseline information which can be used for future management of grazing land resources and to identify feed constraints in the area. The survey data was collected by interviewing a total of 120 households by random selection of two rural kebeles from three altitudes (high, mid and low). To assess grazing land condition, the district was stratified into three altitudes (high, mid and low altitudes). From each altitude, communal and enclosed grazing areas were selected randomly. From each altitude 8 composites and 12 composites from enclosed and 12 composites from communal grazing for herbaceous vegetation and 4 transects from each altitude of communal grazing were selected. Thus, a total of 72 quadrats were used for herbaceous and 12 transects for woody species. For the natural pasture condition assessment, analyses of variance (ANOVA) were carried out by the General Linear Model (GLM) procedure of SAS. Mean separation was tested using the least significant difference. The main feed resources to the livestock in all altitudes were natural pasture, crop residues and stubble grazing. During dry season, crop residues was the first livestock feed source followed by natural pasture in all altitudes. However, during wet season, natural pasture was the first livestock feed source followed by crop resides in all altitudes. In terms of dry matter (DM) crop residues contributed the highest proportion (66.7%) of the total feed sources. The DM obtained from crop residues significantly varied (P<0.05) among the altitudes. The total annual estimated available feed supply to maintain the livestock in the area satisfied only 79.4%. The conservation of feed resources in the form of hay in high, mid and low altitudes was 38.5, 80, and 22.5%, respectively. But, none of the respondents used silage in the study area due to lack of knowledge how to make it. In the district, a total of 21 herbaceous species were identified, from these 57, 24 and 19% were grasses, legumes and other species, respectively. Based on dry matter of biomass, Medicago polymorpha in high and mid altitudes and Eleusine floccifolia in low altitude were the dominant species. Altitude and grazing have effects on grazing land conditions and biomass production. The average dry matter yield of grasses, legumes and total biomass had a significant difference among altitudes in enclosed and communal grazing areas. The average dry matter yield of grasses, legumes, and total biomass were higher in enclosed area than communal grazing areas in all altitudes. There were a significant (P<0.01) interaction of altitude and grazing on biomass and species composition. There was positive correlation of species composition, grass species composition and basal cover with biomass. Crop residues and natural pastures are the major feed resources in dry and wet seasons, respectively. The total annual dry matter does not meet the total livestock requirement per annum in district. Further research and development work is recommended to alleviate feed shortage through different options such as development of improved forages and alternative means of crop residue utilization and conservation of feed in the form hay and crop residues.

The Present study was aimed to estimate and investigate some physico-chemical parameters of Dal Lake of Kashmir, India. During the present study water samples from five basins were collected and analyzed for the physicochemical properties. Analysis showed a great variation in water quality among the different basins. Much polluted basins i.e., Telebal and Jogilankar are having deteriorated water qualities and possible reason for this could be the increasing eutrophication resulting from agricultural practices in the nearby catchment area or tourism activity.

This study indicated the status of drinking water containing two heavy metals (Zinc and Lead) in case of the areas adjacent to tannery industries located in Dhaka city as well as outside areas. The drinking water was collected from both tube wells and taps, and then metals were determined using Flame AAS. Both Zinc and Lead content was found highest in the tap water of the area of tanneries named Hazaribagh expressing as 54 ppb and 200 ppb respectively. But in tube well water of this area, the amount of Zinc ranges from 31 ppb to 50 ppb but the Lead content was found as nil. Again areas far from tanneries, the lead content was found 138 ppb as highest.

This study was carried out to determine the potential occurrence of pesticide residues in the milk of buffalo and women, which exists in vegetables and fruits farming community in Rosetta region Northern of Delta, Egypt. Milk samples were analyzed by gas chromatography-electron capture detector. Halogenated pesticides were selected includes: 1- Organochlorines; Hexachlorocyclohexane isomers (a, ß, ?-HCHs), dichlorodiphenyltrichloroethane (p, p' – DDT) and its degradates; p, p'-DDD and DDE, and cyclodiene compounds; Aldrin, dieldrin and endrin. 2- Organophosphorous pesticides; Chlorpyrifos, chlorpyrifos methyl and profenofos. 3- Pyrethroids; Cypermethrin and lambda-cyhalothrin. The tested organochlorine pesticides were detected in most of the samples analyzed at lower frequencies and levels ranged from 2.38 to 3.57 µg/kg in buffalo than of human milk (2.4-5.78 µg/kg). Whereas organophosphorous and pyrethroids found at high predominance of frequencies among all the tested compounds in the buffalo milk than in human milk analyzed. Generally, all samples were positive for at least one of the pesticides; Chlorpyrifos, chlorpyrifos, methyl, profenfos or cypermethrin with mean levels ranged from 1.9 to 5.14 µg/kg of the two milk types, except lambdacyhalothrin at below detection limit in all human breast milk samples. Statistically, significant difference and correlation of organochlorines levels (but no significant difference or correlation for organophosphorous and pyrethroids) were found between the two types of milk investigated. The data available for estimation of daily intakes (ADIs) and extraneous and maximum residue limits (ERLs & MRLs) revealed that these compounds were found to be lower than the safety thresholds level. Results of this study indicated that in spite of the banning much of organochlorine pesticides (rather than the currently applied (e.g., organophosphorous and pyrethroid pesticides), still contaminating the food stuffs, particularly milk.