环境与分析毒理学

The objective of this study was to characterize the occurrence and concentration of pesticides and polycyclic aromatic hydrocarbons (PAH) in household dust in North Carolina. Human exposure to these contaminants in the indoor environment is of concern since little degradation takes place indoors resulting in chronic exposure to a mixture of contaminants. In addition, children may be more highly exposed due to hand-to-mouth activities and increasing time spent indoors. We recruited 199 households in Central and Eastern North Carolina and collected composite dust samples over two April-October sampling seasons during 2003 and 2004. Dust samples were analyzed for 16 pesticides (α-chlordane, γ-chlordane, 2,4-D(2-ethylhexyl) ester, alachlor, carbaryl, chlorpyrifos, cis- and transpermethrin, 4,4’-DDE, 4,4’-DDT, dieldrin, diazinon, heptachlor, lindane, methoxychlor, and ortho-phenylphenol) andfour PAH compounds (benzo(b)fluoranthene , chrysene/iso-chrysene, benzo(a)pyrene, and benz(a)anthracene). The frequency of detection varied for the pesticides; the median number of pesticides detected in sampled homes was seven. The four PAH were found in more than 97% of sampled homes. Detection frequency and concentration of insecticides banned for residential uses were significantly associated with whether the residence was built before or after the ban year (P<0.001 in all cases except for dieldrin where P<0.01, and methoxychlor). Under maximum exposure scenarios, somewhat elevated health risk estimates were calculated, with the majority of the risk attributable to exposure to the banned insecticides dieldrin and DDT. This study provides additional regional data about the mixture and level of contaminants in household dust in the southeastern U.S.

China implemented the South to North Water Division Project (SNWDP) in 2002, and the three-route (i.e., East, Middle, and West) Project is capable of transferring a total of 41.3 billion m3 of water annually from the water rich Yangtze River to the drought Northern China. The upper Han River basin is the water source area of the SNWDP’s Middle Route, thus its aquatic ecosystem and water quality is of great concern. Field surveys and estimated soil erosion concerned with morphological properties from digital terrain model and land use/land cover were conducted and water quality variables were examined in April and October 2006 respectively in order to determine the major eco-environmental consequences such as land use and soil erosion, water pollution and building of hydropower dams in the basin. Hydroclimatologic data from Ankang and Danjiangkou demonstrated temperature rise of 0.29 °C/10 a, and significantly decreases of precipitation and runoff (78×108 m3/10 a) in the recent 30 years. The upper Han River catchment with an erosion intensity of 1980-4400 t/km2/yr, transported 3×108 t/yr of soils to the river, and 40% of the riparian zone in some sub catchment was cultivated though the entire basin had a vegetated coverage of 77%. Moreover, chemical oxygen demand (COD) and nitrogen were the major pollutants in the upper Han River with considerably increases in the past 40 years, which would be further exaggerated by dam construction and global warming. Ultimately, corresponding strategies including proper land use, water pollution control, ecologically sustainable management for hydropower station and establishment of eco-environmental monitoring network were introduced for maintaining a scientifically sound aquatic ecosystem and satisfactory water quality in the upper Han River for the interbasin water transfer project.

Introduction: Medicinal plants have been used therapeutically all around the world, being an important aspect of various traditional medicine systems. However, the use of phytotherapy according to the efficacy and safety criteria is not sufficient to guarantee the quality of both the herbal medicine and its use.
Objective : The aim of this study was to determine the level of Cd, Pb, Ni, Cu , Hg and pesticide residues in some commonly used herbal medicines and herbal plants to assess the relative safety of these products based on world standard limits and potential health risk to local inhabitants.
Materials & Methods: 6 different medicinal herbal products and 6 herbal plants were purchased from Tehran’s market. Certain weight of each samples were digested with nitric acid by wet digestion method for determining of toxic metals. Atomic absorption spectrometry (AA) was used for the determination of the concentration of Pb, Cd, Ni, Cu and an automated continuous – flow hydride vapor generation system was used for Hg and pesticide residues were analyzed by gas-chromatography – mass spectrometry after extraction performed using solid – phase micro extraction technique.
Results: Results were compared with the permissible limits (Pl), acceptable daily intake (ADI) and provisional maximum tolerable daily intake (PMTDI) as set by world health organization (WHO), Food and Drug administration (FDA). Mercury, Lead and Cadmium were highly present in the majority of samples. In 100% of medicinal plant samples which brought randomly from the markets, the amounts of Diazinon, Fenitrothion, Malathion was higher than the allowed limits when compared to the MRL scale.
Conclusion: By a comparison between acceptable global standards and the level of Hg, Cd and Pb on investigated herbal medicine and medicinal plants, our results showed that the majority of medicinal plants samples had higher level of these heavy metals. Due to lack of research data and technical limitations at present, more research is needed in order to establish the scientific criteria for herbal medicines.

The effect of copper sulphate on liver, gills and kidney of fish Channa punctatus was observed as metabolic indicators. The fish were exposed to sub-lethal (0.36 mg l-1) concentrations for 15, 30 and 45 days. The observations revealed that in the presence of copper sulphate the metabolic enzymes aspirate amino transferases (ASAT) and alanine amino transferases (ALAT) can enhance their activity, while catalase activity significantly reduced in response to elevated level of superoxide production in exposed fish as compared to healthy subjects. The major effect of copper sulphate toxicity on exposed fish shows as reduced amount of protein content as compared to unexposed fish. However, ASAT level have a significant negative correlation between catalase activity (r = 0.833, t = 6.3872, p 0.05) and protein content (r = 0.8916, t = 8.3540, p 0.05) in the exposed organs. These findings suggest that the significant increase of transaminase activity while reduced amount of catalase and protein content might be the consequences of tissue damage in Channa Punctatus.

With more public awareness about environmental issues mainly in developed countries when they found the Chlorophenolic compounds (AOX) in the fish stock receiving bleach plant effluent, draw much attention regarding the toxicity value of bleach plant effluent. In this paper, I have mainly described the fish toxicity and microtox toxicity value of bleach plant effluents and their relationship in agro & wood based mills. Toxicity studies were done on chlorination stage, Extraction stage, Hypo stage and combined bleach effluents of agro and wood based mills. Studies show that the E-stage effluents are having high fish mortality rate at lower % volume concentration & high % inhibition of Luminescent bacteria, indicating that it is more toxic than the other stage bleach effluent. Studies also shows that scenario of agro based small pulp and paper mills are not good and releases high toxic bleach effluent as compared to wood based large pulp and paper mills due to low scale of operation and use of high dose of bleach chemical due to economical reason.

The adsorption and de-sorption properties of polycyclic aromatic hydrocarbons (PAH) which was represented by pure phenanthrene, on activated carbon were investigated. The influences of solvent (acetone,carbon tetrachloride, tetrahydrofuran, ethanol or distilled water), time and manner (with ultrasonic or not) on the desorption efficiency were investigated. The results show that the de-sorption efficiency reaches 91.40% which exhibits the highest efficiency when the ethanol is used as the de-sorption solvent and the system was treated with ultrasonic technology. The desorption test was also carried on the raw coconut shell-based activated carbon and it was not being used before. This determination is to understand the “baseline background” and the purity of raw activated carbon characteristics. The content of total de-sorption amounts was 0.043% of raw activated carbon. Through GC/MS analysis,the main desorption substance defined was 10-undecenoic acid methyl ester.

Environment pollution can be determined using physical and chemical methods and with bio-indicators. In recent years there has been an increased interest on the use of human bio-indicators such as teeth, bone, blood, nail and hair to monitor environment pollution with toxic heavy metals. Therefore the determination of heavy metals content in teeth is understood to play an important role for monitoring the impact of environmental pollution. The aim of this review of literature is to illustrate the current status of teeth used as indicators in environmental pollution with lead.

Environmental pollution of waters caused by the release of chemical substances is becoming a threat for both man and the environment. The active pharmacological agents discharged into the waters, can interact with the cell DNA and induce genetic damage. The aim of the present work was to evaluate the potential genotoxic effects of nine pharmacological agents, Atorvastatin, Sildenafil citrate, Gemfibrozil, Ibuprofen, Atenolol, Ofloxacin, Carbamazepine, Bezafibrate, and Diclofenac present in the waste waters of some Italian treatment plants. Genotoxic effects of the nine pharmacological compounds were evaluated by using four tests, the Comet Assay, the Diffusion Assay, the TUNEL test, and RAPD-PCR technique. The sperm cells were exposed in vitro for three different times: 15, 30 and 45 min at the mean concentrations detected in the waste waters. All drugs tested induced a statistically significant reduction in the integrity of sperm DNA and high fragmentation values. The drugs found in the wastewater were then able to induce damage to sperm DNA, highlighted in a very early stage of cell suffering, even before they are capable of inducing other metabolic disorders.