环境与分析毒理学

Synthetic turf, made with an infill of rubber crumb from used tyres or virgin rubber, is now common in many sporting facilities. It is known that it contains compounds such as polycyclic aromatic hydrocarbons (PAHs) and heavy metals. We evaluated in nine samples of rubber crumb the total content of some heavy metals (Zn, Cd, Pb, Cu, Cr, Ni, Fe) normally found in tyres by microwave mineralization and the levels of the 14 US EPA priority PAHs by Soxhlet extraction and HPLC analysis. The results showed high levels of PAHs and zinc in all rubber crumb samples compared to rubber granulate limits set by Italian National Amateur League (LND). Following the precautionary principle, a risk assessment at 25°C was done, using the Average Daily Dose (ADD) assumed by athletes, expressed in terms of mass of contaminant per unit of body weight per day (mg/kg day), and the Lifetime Average Daily Dose (LADD) and then evaluating the Hazard Index (HI) and the Cumulative Excess Cancer Risk (ΣECR). In the different rubber granulates samples the HI ranges from a minimum of 8.94×10-7 to a maximum of 1.16×10-6, while the ΣECR ranges from a minimum of 4.91×10-9 to a maximum of 1.10×10-8. Finally, the aim of this study was to estimate the “hazard” for athletes inhaling PAHs released at the high temperatures this synthetic turf may reach. Then a sequence of proofs was carried out at 60°C, a temperature that this rubber crumb can easily reach in sporting installations, to see whether PAH release occurs. The toxicity equivalent (TEQ) of evaporates from rubber crumb is not negligible and represents a major contribution to the total daily intake of PAHs by different routes.

The preparation of Activated Carbon from Apricot Stone (ASAC) with H3PO4 and its ability to remove the Coomassie Blue (CB) used in textile industry from aqueous solutions are reported in this study. The FTIR spectroscopy is used to get information on interactions between the adsorbent and CB. A series of contact time experiments were undertaken in stirred batch adsorber to assess the effect of the system variables. The results were discussed and showed that ASAC can be used in the wastewater treatment. A comparison of two models on the overall adsorption rate showed that the kinetic of adsorption was better described by the pseudo-second order model. The adsorption isotherms of CB onto ASAC are determined and correlated with common isotherms equations. The smaller RMSE values obtained for the Freundlich model indicate the better curve fitting; the monolayer adsorption capacity of CB is found to be 10.09 mg/g at temperature 22.5 °C and 98.022 mg/g at temperature 50 °C and pH ~ 2. The thermodynamic parameters indicate the spontaneous and exothermic nature of the adsorption process. The positive value of the entropy (ΔS) clearly that the randomness in decreased at the solid-solution interface during the CB adsorption onto ASAC, indicating that some structural exchange may occur among the active sites of the adsorbent and the ions. The activation energy (66.161 kJ/ mol) indicates that the chemical adsorption was predominant.

Concentrations of copper, lead and zinc in sediments downstream of a metallurgical facility on the the Upper Columbia River (UCR) were significantly greater than those in regional reference locations. Sturgeons inhabit benthic habitats and there is concern that they might be at greater risk of exposure. A laboratory based, flow-through, experimental exposure system was used to characterize toxicity of metals in the different matrices associated with sediments collected from the UCR, and to assess risk to early life stages of white sturgeon (Acipenser transmontanus) under chronic bioassay conditions. Bioavailability and concentrations of metals in pore water, overlying water, and at the sediment-water interface were characterized. Several sampling methods including peepers, diffusive gradients in thin films (DGTs), and active sampling/suction techniques were employed. Results indicated that concentrations of metals in site sediments were significantly greater in comparison to upstream reference sediments. Of the four primary metals of concern, concentrations of copper, primarily in pore water, were significantly greater in exposure chambers containing site sediments compared to reference sediments. In addition, the different sampling techniques resulted in varying estimates of concentration depending on matrix, analyte, and method, and the present study highlights challenges in assessing the true risk of exposure. The analytical data reported herein is utilized in a parallel article to characterize risk and compare predictions to the bioassay results.

In the Upper Columbia River (UCR) between Trail, BC, and Grand Coulee Dam, WA, it has been hypothesized that metals associated with sediments might be contributing to poor recruitment of white sturgeon. Accordingly, the present study employed laboratory flow-through tests to characterize chronic toxicity of UCR sediments to early life stages of white sturgeon (Acipenser transmontanus). Sediments were collected from areas of the UCR known to be sturgeon spawning- and/or nursing-grounds and contained a range of concentrations of metals of primary interest, including copper (Cu), cadmium (Cd), lead (Pb), and zinc (Zn). Early life stage white sturgeon were exposed for 60 days and survival and growth were related to concentrations of metals in bulk sediment, pore water, overlying water, and water at the sediment-water interface. Based on probable effect concentrations (PECs) and excess simultaneously extracted metals (SEMX), site sediments in the present study had the potential to elicit adverse effects to sediment-dwelling organisms. In addition, the Biotic Ligand Model (BLM) was used to allow for more explicit consideration of bioavailability of metals to white sturgeon. BLM predictions indicated that concentrations of Cu in pore water slightly exceeded the threshold for effects (up to a factor of 2.2) for two of the five site sediments, while concentrations of metals in overlying water and at the sediment-water interface were below the threshold for effects. No effects were observed, however, in survival or growth of white sturgeon exposed to site sediments that were relatable to concentrations of metals. Of the methods used to characterize potential effects due to exposure to metals associated with sediments, BLM predictions corresponded best with the observed results.

Although there are few published studies of residential exposures to environmental contaminants in Nepal, there may be substantial exposures to multiple contaminants in Nepali households. Pesticides, which can be harmful to human health, are often used by Nepali farmers, and many farmers lack an understanding of the appropriate procedures for the safe use, handling and storage of pesticides. In addition, many Nepali families use wood burning stoves, leading to the potential for exposure to polycyclic aromatic hydrocarbons from wood smoke. This study measured the levels of four organophosphate pesticides, 22 organochlorine pesticides, and over thirty polycyclic aromatic hydrocarbons in house dust from two rural Nepali villages. Floor dust samples were collected in early summer from a total of 18 households, including nine households in the village of Keraghari, in Kavrepalanchok District, and nine homes in the village of Kafaldanda, in Lalitpur District. These villages have similar environmental features and are located at an altitude of approximately 2,000 meters. In these two villages, many of the homes have improved cookstoves to reduce smoke levels in the homes. The dust samples were collected using pre-ashed glass fiber filter cloths saturated with isopropyl alcohol. In both villages, the organochlorine pesticide that was present in the highest concentrations was the DDT metabolite p,p’-dichlorodiphenyldichloroethylene (4,4’-DDE). Among the organophosphates, methyl parathion accounted for much of the organophosphate mass detected. Across both villages, the median total organochlorine pesticide value (287 ng/m2) was 5-fold higher than the median total organophosphate pesticide value (54.3 ng/m2). The median total polycyclic aromatic hydrocarbon concentration in house dust from both villages was 14,700 ng/m2. Interventions are needed to improve safe handling and use of pesticides in Nepali villages. Additional studies are also needed to assess the extent to which improved cookstoves reduce polycyclic aromatic hydrocarbon exposure, during both winter and summer.

The purpose of this study was to produce data on the ethanol concentrations in ambient air that result from hand rubbings with hydroalcoholic solutions (HAS) or the use of ethanol-based varnishes, and then to predict the blood ethanol levels (BELs) that result from these procedures. The concentration of ethanol in air at the volunteer’s nose after the application of HAS on hands was measured with five volunteers who performed five tests in two different environments: 1) in an inhalation chamber (air change rate ~18 h-1), and 2) in a closed office (poorly ventilated) with two different amounts (1.5 and 3 g) of HAS. In the case of varnish, 125 ml were applied on a 1-m2 wood surface placed in the middle of an inhalation chamber (n=4). The ethanol concentration was measured 20 cm and 40 cm from the center of the board for the next 60 minutes. As for HAS we noted a large intra- and inter-individual variability in ethanol levels in inhaled air. As expected the highest concentration in the inhalation chamber (~1250 ppm) was lower than in the office (~2352 ppm). For the application of the varnish, the ethanol concentrations greatly exceeded 1000 ppm for a short duration (< 4 min). Physiologically-based pharmacokinetic (PBPK) modeling of ethanol concentrations based on ethanol levels measured in inhaled air predicted the following maximum BELs in women (men): 0.39 and 0.37 mg/L (0.37 and 0.35 mg/L) in the office, and 0.26 and 0.42 mg/L (0.25 and 0.40 mg/L ) in the inhalation chamber for 1.5 g and 3 g, respectively. The total dose of ethanol absorbed estimated for a working day involving 42 hand rubbings with 1.5 or 3 g of HAS averaged 0.20 g. For the varnish, the predicted highest BELs for men and women were 0.77 and 0.79 mg/L, respectively. In all cases, the BELs remained below 1 mg/L. The results of this study should make it easier to assess the risk related to chronic inhalation of low levels of ethanol in the general population and among workers associated with these practices.

This paper describes a method for simultaneous determination of eleven mycotoxins in chilli powder, dried fish, peanuts and rice using Liquid Chromatography-Mass Spectrometry (LC-MS/MS). The method is based upon a single extraction step followed by analysis of the diluted crude extract. The proposed method was applied for the simultaneous quantification of multi-residue mycotoxins in 80 samples. The results showed that four chilli powder and twelve peanut samples of a total 80 analyzed samples were contaminated with levels greater than the EC regulatory limit for AFB1.

Tyres are a mixture of vulcanized or cross-linked polymers, carbon black, dispersing oil, sulphur, synthetic fibres, pigments, processing chemicals and steel/fiberglass. Burning of tyre materials produces smoke and toxic air pollutants, including benzene, dioxins, furans, heavy metals and polycyclic aromatic hydrocarbons (PAHs). We investigated the effects of the accumulation of these toxicants on fish smoked with waste tyre materials as fuel source on liver function and oxidative stress parameters in Albino Wistar rats. In this toxicological study, some of the rats were exposed to diet formulated with the smoked fish and some were allowed diets formulated with smoked fish and/or Solanum lycopersicum and Allium cepa. At the end of the study period, the liver function parameters (total protein, albumin, AST, ALP, ALP, bilirubin and cholesterol) indicated negative hepatic changes with adverse fluctuations in oxidative stress parameters (GPx, catalase, SOD, GSH and MDA). Incorporation of S. lycopersicum and A. cepa in the diets ameliorated these adverse biochemical changes in rats exposed to fish smoked with these toxic materials.

Co-precipitation technique using copper (II) methylbutyldithiocarbamate prior to Nickel (II), manganese (II), cobalt (II), lead (II) and chromium (III) determinations their aqueous standard solutions by spectrophotometric method was developed in this study. The effect of pH, sample volume, amounts of methylbutyldithiocarbamate and copper (II) on the recovery of metal ions were studied. The heavy metals in the precipitate were determined by Flame Atomic Absorption Spectrophotometry (FAAS). The detection limits for the determination ranged from 0.003 mg/L to 0.006 mg/L. The coprecipitation procedure was applied for spectrophotometric determination of the heavy metals in water and sediment samples from River Ufara in Igbokoda of Ondo State, part of Nigeria where oil companies were at a time already operating. The mean concentration (ppm) of Ni, Mn, Co, Pb and Cr were 11.7 ± 5.5 and 13.2 ± 1.1; 18.7 ± 4.2 and 63.4 ± 18.2; 1.52 ± 0.11 and 5.60 ± 1.30; 7.8 ± 1.5 and 21.9 ± 3.2; 6.06 ± 0.80 and 19.5 ± 0.9 for water and sediment samples respectively. The mean concentrations of these metals for samples from this area were significantly different from corresponding concentrations for control samples which signified an evidence of metal pollution attributed to oil relating activities. There was also no significant difference in the concentrations of metals in samples using spectrometric technique with co-precipitation procedure and without co-precipitation procedure.

The present study was initiated to investigate the influence of oral application of charcoal, sauerkraut juice and humic acids on specific gastrointestinal microbiota and selected enzymes, electrolytes, and substrates in the blood of dairy cows fed GMO feeds containing glyphosate. A total of 380 Schleswig Holstein cows suffering from symptoms of chronic botulism were fed sequentially with 400 g/animal charcoal daily for 4 weeks (weeks 1-4 of the study), 200 g/ animal charcoal (weeks 5-10 of the study), 200 g charcoal and 500 ml Sauerkraut juice/animal (weeks 11-14 of the study), 120 g/animal humic acids (weeks 15-18 of the study) 200 g charcoal and 100 mL Aquahumin/animal (weeks 19- 20 the of study), or 100 g charcoal and 50 mL Aquahumin (weeks 21-22 of the study) followed by 4 weeks without any supplementation. There was a significant reduction of glyphosate in urine following supplementation with a combination of 200g charcoal plus either 500 mL sauerkraut juice or humic acid. From all of the parameters investigated in blood and urine, distinctive effects were only seen as a lack of manganese and cobalt and a significant reduction of creatinine excretion by urine. All other measured parameters such as creatine kinase (CK), alkaline phosphatase (AP), glutamate dehydrogenase (GLDH), glutamate oxaloacetate transaminase (GOT), and cholesterol, urea, and blood creatinine) were not significantly changed. A significant increase of fecal Gram-negative bacteria and enterococci were only seen at week 8 (200 g charcoal/d) and week 20 (200 g charcoal+100 mL Aquahumin). In conclusion, a charcoal-sauerkraut juice combination and humic acids reduced glyphosate excretion by urine and led to the improved health of animals.

The present study is undertaken to evaluate the protective effects of vitamin C (VC) against methomyl-induced oxidative stress and testicular injures in Wister rat. Male rats were randomly divided into 4 groups of 6 rats each. The route of application selected for the study was oral gavage for 28 consecutive days. Group 1 was served as a control, whereas group 2 was supplemented with VC (200 mg kg-1 body weight, bw). Group 3 was administered with a dose of methomyl equivalent to 1/10 LD50 (2.034 mg kg-1 bw), whereas group 4 was co-administered VC and methomyl as the same dose of groups 2 and 3, respectively. Sub-acute exposure of rats to methomyl for 28 consecutive days resulted in a significant increase in testicular lipid peroxidation (LPO) and a decrease in glutathione (GSH) level. In addition, the testicular activities of catalase (CAT), superoxide dismutase (SOD) and glutathione-S-transferase (GST) enzymes were significantly decline in response to methomyl exposure. Furthermore, histopathological studies in testis of rats treated with methomyl exhibited incomplete spermatogenic series in seminiferous tubules and necrosis of spermatogoneal cells lining seminiferous tubules. Notably, the co-administration of VC modulated the biochemical parameters and the intensity of histopathological findings. The effect of VC on transcriptional activity of four key stress and apoptosisrelated genes (CASP3, CASP9, Tp53 and Bcl2), in response to methomyl exposure in rats, was investigated. Results revealed a significant up-regulation in the level of the expression for the tested genes, however supplementation of VC to methomyl-treated rats modulated the observed significant up-regulation in the level of the expression for those genes, indicative of an protective interfering role in the signaling transduction process of methomyl-mediated toxicity. In conclusion, these data suggested that administration of VC may partially protect against methomyl induced testicular oxidative damage and apoptosis-related genes.

This study entailed the assessment of physical parameters of selected tropical wetlands within Lake Victoria Basin. The research study measured rainfall, flow rate, turbidity, and pH of Kigwal/Kimondi, Nyando and Nzoia wetland ecosystems found within eastern side of Lake Victoria Basin by use of Vernier Calliper Instrument. The study found out that approximately 78 to 89% of recharge water was retained with the highest calculated water budget being for Nzoia wetland (26.24(0.99) × 106 m3) during rainy season with Kigwal/Kimondi (8.85 (2.91) × 106 m3) and Nyando (11.47 (0.75) × 106 m3). There was a seasonal variation of flow rate, pH, and turbidity with rain season indicating high levels of turbidity, flow rate and variable pH levels in the wetland ecosystems as compared to dry seasons. A statistically significant correlation existed between the measured parameters with coefficient of correlation ranging from r=0.8976 to 0.9987 with p < 0.05). Turbidity values of the three wetlands at the inlets during rainy season were above the recommended values by EPA but decreased considerably at the exit of the wetlands to within the recommended NTUs by EPA of 1 to 5 NTUs. There was a highly correlated relationship between rainfall amounts, flow rate and turbidity.pH values ranged from slightly acidic (6.79(± 0.55)) at the inlets) to basic nature (8.44(± 0.17)) especially at the outlets of the wetland ecosystems. Intervention programs should be initiated to ensure that physical properties of wetlands are secured.

Eight samples of commonly consumed powdered milk by adults were collected from local markets in Oke-Ogun area, Nigeria and analyzed using gamma ray spectrometer with NaI(Tl) detector for radioactive analysis and Atomic Absorption Spectrophotometer for heavy metal analysis (Pb, Fe, Cd and Cu). The main activity concentration detected is that of 40K with average of 39.6 Bq.kg-1 while the activities of 226Ra and 232Th were below detection limit (BDL). The total annual effective dose due to the ingestion of radionuclide in the milk sample was estimated to be <33.7 μSv.y-1 which is lower than the ICRP recommended limit of 1mSv.y-1 for all ages. The geometric means of Pb, Cd, Fe and Cu in the samples were found to be 0.024, 0.328, 2.168 and 0.242 mg.kg-1, respectively and the annual daily dose estimated were 0.1490, 0.010, 0.0002 and 0.0003 mg.day-1, respectively. The results of the hazard index revealed that the intake of heavy metal through ingestion of the milk samples did not exceeds the recommended limit of unity. Therefore, the consumption of these milk samples is safe.

Background: High prevalence of cataract especially in women, children and urban dwellers and associated blindness is a major problem of Pakistan and low and middle income countries. Prevalence of tobacco use is also very high in Pakistan. The aim of study was to identify association between cigarette smoking and development of cataract in people of Karachi and to determine effect of Lead, Cadmium and Copper in progression of Cataract Material and methods: 100 Cataract Patients including Smokers and Non-Smokers visiting LRBT Hospital. Karachi was selected randomly. After Surgical Removal, their lenses were analyzed for Cadmium, Lead and Copper Concentration by Atomic Absorption Spectrometer at Pakistan Council of Scientific and Industrial Research Results: Concentration of Cadmium, Lead and Copper were found to be significantly higher among Lenses of Smokers than Non-Smokers. Conclusion: Cataract development occurred earlier in heavy smokers with mean age 48.24 years as compared to non-smokers mean age 55.72 years along-with increased accumulation of Cadmium, Lead and Copper in their lenses. The result shows an association between Cigarette Smoking and progression of Cataract