Dynamics of pesticide residues in nectar and pollen of mustard (Brassica juncea (L.) Czern.) grown in Himachal Pradesh (India)

Residues dynamics of Endosulfan (525.00 g a.i. ha(-1)), Imidacloprid seed treatment (21 g a.i. kg(-1)), Lambdacyhalothrin (75.00 g a.i. ha(-1)) and Spiromesifen (225.00 g a.i. ha(-1)) in nectar and pollen of mustard, Brassica juncea (L.) Czern. grown in Himachal Pradesh (India) were determined through bioassay (using Drosophila melanogaster Meig. as test organism) and GC (Gas chromatographic) and HPLC (High performance liquid chromatographic) methods. In general chromatographic methods were more sensitive for the determination of above given pesticides compared to bioassay method. Average recoveries in nectar samples varied between 82.85 and 88.90% by bioassay and 91.20 and 93.55% by chromatographic techniques. In pollen samples, recoveries varied between 81.44 and 86.44% by bioassay and 88.50 and 91.30% by chromatographic methods. Imidacloprid residues were neither found in nectar nor in pollen samples at the time of sampling i.e. 50% of flowering. The order of average half life of residues was: Lambdacyhalothrin (12.45 h) < Spiromesifen (19.99 h) < Endosulfan (27.49 h) for nectar and Spiromesifen (9.69 h) < Lambdacyhalothrin (12.44 h) < Endosulfan (17.84 h) for pollen samples. It was found that Imidcloprid seed treatment was practically harmless to honey bees, whereas a waiting period of 5 days must be observed on crops sprayed with these chemicals during blooms to avoid any accidental hazards to honey bees.     

Size Distribution of Aerosols (PM10) and Lead (Pb) near Traffic Intersections in Mumbai (India)

The size distribution of aerosols was measured near traffic intersections of Marol link road in air quality control region (AQCR1), which is a moderately industrial area and Dadar Khodad circle in AQCR2, which is a heavily commercial core of the Mumbai City. The reason behind selecting the two unidentical regions was to study the contribution from vehicles to the size separated PM10 and that of Pb. It is recognised that particulates in urban air are responsible for serious health effects. As very small particles are assumed to be important for the adverse health effects, the particle size distribution is thus an important factor that needs to be addressed whenever the particulates pollution is concerned. The size measurements were done with a cascade impactor of eight stages with a back-up filter. It effectively separates the particulate matter into nine-sizes ranging from 0.0-0.4 to 9.0-10.0 microm. Samples were analysed in nine-particle size fractions with special reference to a toxic metal - lead (Pb) by atomic absorption spectrophotometry (AAS). It was found that PM10 and Pb at both the intersections could easily be classified by the size distribution. The fractions of the PM10 and that of Pb showing a tendency of trimodal distributions with the first peak at coarse mode approximately 9.0-10.0 microm, second at approximately 5.8 microm and the third at coarse mode approximately1.1 microm. The significant percentage of Pb was found in the range below 2.5 microm at both the intersections. However, Pb in AQCR1 is found in the coarser range as well, which could probably be the influence of various industrial activities in the area. PM10 concentration values in the coarser range in AQCR2 are associated with the resuspension of dust particles and mechanical erosions.     

Analysis of umbu (Spondias tuberosa Arruda (Anacardiaceae)) in different landscape management regimes

Plant domestication is an evolutionary process guided by human groups who modify the landscape for their needs. The objective of this study was to evaluate the phenotypic variations between populations of Spondias tuberosa Arruda (umbuzeiro) when subjected to different local landscape management strategies. The influence of the landscape management system on these populations was evaluated in five identified regional units (mountains, base of mountains, pastures, cultivated areas and home gardens). Ten individuals were randomly selected from each region and subjected to morphological and chemical fruit analysis. The diversity index, based on Simpson's index, was determined for the different populations. We then evaluated the morphological differences between the individual fruits from the distinct landscape areas. We observed no significant differences in morphological diversity between the areas studied. Our data suggest that the umbuzeiro specimens in this region may be in the process of incipient domestication.     

The effect of light and iron(II)/iron(III) on the distribution of Tl(I)/Tl(III) in fresh water systems

The distribution of aqueous Tl(I)/Tl(III) as a function of light exposure and solution properties was studied by quantifying the oxidation states after separation with ion chromatography and on-line detection with ICP-MS. Ultraviolet irradiation of aqueous solutions containing 1 microg l(-1) Tl(III) and in equilibrium with the atmosphere increases the reduction rate. In systems with photoreduction of Fe(III)(aq) a quantitative oxidation of Tl(I)(aq) was observed, notably at low pH. The process is reversible, as indicated by formation of Tl(I) when the irradiated systems were kept in the dark. In systems with colloidal silica-stabilised ferrihydrite, UV irradiation also leads to oxidation of Tl(I)(aq), but not quantitatively. It is suggested that adsorption of thallium to the ferrihydrite determines the rate of oxidation. Detectable, but not quantitative, oxidation of Tl(I)(aq) took place when natural water samples with 1 microg l(-1) Tl(I)(aq) were exposed to either sunlight or UV-light. For these samples, the reduction was not quantitative when they were kept in the dark for 24 h. The results suggest that the light dependent iron cycle in fresh water systems strongly influences the redox state of thallium.     

A regional survey of malformed frogs in Minnesota (USA) (Minnesota malformed frogs)

In late 1995, school children discovered malformedfrogs in a south central Minnesota pond. Press coverage resultedin numerous citizen reports of frog malformation across Minnesotain 1996. After some initial site investigation, 3 affected frogsites and 4 nearby reference sites were selected for moredetailed evaluation. Field biologists made 89 visits to studysites beginning spring 1997 through fall 1999 to examine thenumber and type of frog malformations. Over 5,100 Leopardfrogs (Rana pipiens) were captured and examined atall study sites. Water elevations and associated littoralinundation were recorded from 1997-2000. Results indicate thatmalformation occurred at all study sites above historicalbackground levels. Rana pipiens malformation across allsites over three seasons averaged 7.9% and ranged from 0 to 7% at reference sites and 4 to 23% at affected sites. At onenorthern Minnesota site, mink frog (Ranaseptentrionalis) malformation was 75% in 1998. A sitecharacteristic common to the most affected sites was an elasticzone of littoral inundation. Climate driven hydrologic variationlikely influenced water depth and associated breeding locations.     

Lead (Pb) and arsenic (As) bioaccessibility in various soils from south China

Serious problems are faced in several parts of the world due to the presence of high concentration of fluoride in drinking water which causes dental and skeletal fluorosis to humans. Nalgonda district in Andhra Pradesh, India is one such region where high concentration of fluoride is present in groundwater. Since there are no major studies in the recent past, the present study was carried out to understand the present status of groundwater quality in Nalgonda and also to assess the possible causes for high concentration of fluoride in groundwater. Samples from 45 wells were collected once every 2 months and analyzed for fluoride concentration using an ion chromatograph. The fluoride concentration in groundwater of this region ranged from 0.1 to 8.8 mg/l with a mean of 1.3 mg/l. About 52% of the samples collected were suitable for human consumption. However, 18% of the samples were having less than the required limit of 0.6 mg/l, and 30% of the samples possessed high concentration of fluoride, i.e., above 1.5 mg/l. Weathering of rocks and evaporation of groundwater are responsible for high fluoride concentration in groundwater of this area apart from anthropogenic activities including irrigation which accelerates weathering of rocks.     

Polycyclic aromatic hydrocarbons (PAHs) in starfish body and bottom sediments in Mohang Harbor (Taean), South Korea

The concentrations of 27 polycyclic aromatic hydrocarbons (PAHs) were determined in bottom sediments and starfish from Mohang Harbor (MH) in Taean peninsula, South Korea. In December 2007, crude oil washed ashore from the M/V Hebei Spirit and was subsequently cleaned up within a few months of the incident. The ecological risk, bioaccumulation factor (BAF), and composition of the 27 PAHs were examined. The PAH concentrations in the bottom sediment ranged from 24 to 366 μg/kg dried weight, and the ecological risk was determined as minimal (mERL-Q?<?1). Total PAH concentrations in Asterina pectinifera (inside seawall) and Asterias amurensis (outside seawall) were 1,226 and 1,477 μg/kg dry weight (d.w.), respectively. The total BAFs (∑BAF) for A. amurensis was 3.8 times higher than that of A. pectinifera, and the PAH concentrations of 5–6 log K _OW were highest in the two starfish species. Further, PAH fingerprint analysis (nine alkyl-substituted PAHs fraction, low molecular weight (LMW)/high molecular weight (HMW), Phe/Ant, and Flu/Pyr), and principal component analysis (PCA) based on three crude oil samples from the M/V Hebei Spirit showed no remaining influence of crude oil.     

Poly(sodium acrylamidoalkanoates) in water treatment

Poly(sodium 6-acrylamidocaproate), poly(sodium 11-acrylamidoundecanoate), poly(sodium 11-N-methylacrylamidoundecanoate) and poly(sodium 11-N-ethylacrylamidoundecanoate) have been synthesized. The performance of these anionic polyelectrolytes as coagulant aids in water treatment was assessed by the jar test. The effects of polymer dosage and pH on their performances were investigated in order to establish the optimum flocculation conditions. The effectiveness of these polyelectrolytes as well as a commercially available cationic polyamine organic coagulant aid was compared in terms of floc size, settling rate and the quality of treated water. Poly(sodium 6-acrylamidocaproate) and poly(sodium 11-acrylamidoundecanoate) were superior to poly(sodium 11-N-methylacrylamidoundecanoate) and poly(sodium 11-N-ethylacrylamidoundecanoate), and they are as effective as the commercial cationic coagulant aid.     

Airborne endotoxin in woodworking (joinery) shops

Symptoms such as shortness of breath and cough have been noted in woodworking facilities even where wood dust itself is well-controlled. Suspicion has fallen on other possible contaminants in the workplace atmosphere, including bacterial endotoxin. A few studies have indicated potentially high endotoxin exposure with exposure to fresh wood in sawmills and in the production of fiberboard and chipboard, but fewer studies have been carried out on exposure to endotoxin in dry wood work, for example in joineries. A study of the endotoxin content of airborne wood dust samples from US woodworking facilities is presented, from the re-analysis of samples which previously had been taken to establish mass collection relationships between the IOM sampler, the closed-face 37 mm plastic cassette (CFC) sampler and the Button sampler. Endotoxin was strongly correlated with total dust, but the endotoxin content of a few fresh wood samples was found to be up to ten times higher per unit of wood dust than for dried-wood samples, and this difference was significant. No long-term time-weighted average sample exceeded the recommended limit value of 50 EU m(-3) (EU, endotoxin units)used in the Netherlands, although a number of the IOM samples came close (seven samples or 44% exceeded 20 EU m(-3)) and one short-term (48 minute) sample registered a high value of 73 EU m(-3). The geometric mean concentration from the IOM samples (11 EU m(-3)) is within the range of geometric means found from Australian joineries (3.7-60, combined: 24 EU m(-3)). In contrast, the corresponding values from the CFC (3.6 EU m(-3)), and the Button sampler (2.1 EU m(-3)) were much lower and no samples exceeded 20 EU m(-3). Endotoxin is likely only to be a significant problem in working with dried woods when associated with very high dust levels, where the wood dust itself is likely to be a cause for concern. The results from the few samples in this study where fresh wood was being worked were similar to results from other studies involving fresh woods. The agreement between these studies is encouraging given the difficulties of endotoxin analysis and the wide variation often expected between different laboratories.     

Occurrence of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in Lake Maggiore (Italy and Switzerland)

Samples of air (gas and particulate phases), bulk deposition, aquatic settling material and sediments were collected in Lake Maggiore (LM) in order to determine their content of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Air (gas and particulate phases) concentrations were 0.5 pg m(-3), 80 pg m(-3), 13 pg m(-3) and 106 pg m(-3) for SigmaPCDD/Fs, SigmaPCBs, Sigma dioxin-like PCBs (DL-PCBs) and SigmaPBDEs, respectively. Deposition fluxes ranged from 0.7 ng m(-2) d(-1) for SigmaPCDD/Fs to 32 ng m(-2) d(-1) for SigmaPCBs. Aquatic settling material presented concentrations of 0.4 ng g(-1) dry weight (dw) for SigmaPCDD/Fs, 13 ng g(-1) dw for SigmaPCB, 3.4 ng g(-1) dw for SigmaDL-PCBs and 5.7 ng g(-1) dw for SigmaPBDEs. Mean sediment concentrations were 0.4 ng g(-1) dw for SigmaPCDD/Fs, 11 ng g(-1) dw for SigmaPCB, 3 ng g(-1) dw for SigmaDL-PCBs and 5.1 ng g(-1) dw for SigmaPBDEs. Similar PCDD/F and DL-PCB congener patterns in all the environmental compartments of LM point to an important, if not dominant, contribution of atmospheric deposition as source of these pollutants into LM. In contrast, PBDE congener distribution was not similar in the different environmental compartments. BDE 47 dominated air and settling material, while BDE 209 was the predominant congener in the bulk atmospheric deposition. Moreover, sediments showed two distinct PBDE congener profiles. Lower PBDE concentrated sediments were dominated by congeners 47 and 99, while BDE 209 dominated in higher PBDE concentrated samples. This suggests the influence of local sources as well as atmospheric input of PBDEs into LM.     

Preliminary screening of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD) and tetrabromobisphenol A (TBBPA) flame retardants in landfill leachate

The occurrence of selected brominated flame retardants, including nine polybrominated diphenyl ether (PBDE) congeners, hexabromocyclododecane (HBCDD) and tetrabromobisphenol A (TBBPA) in leachate samples from eight landfill sites in South Africa, were investigated. In addition, the possible influences of dissolved organic carbon on their levels were also evaluated. Filtered leachate samples were subjected to solid-phase extraction to isolate the various target compounds. PBDEs with six bromine substituents and above, as well as α-HBCDD, β-HBCDD and TBBPA, were generally found below the detection limit. However, the mean value of the total lower PBDE congeners ranged between 0.04 and 0.48 μg L^?1, and the concentrations of γ-HBCDD ranged from not detectable (ND) to 0.05 μg L^?1. No significant correlation was observed between the target compounds and dissolved organic carbon, although weak to moderate correlations were mostly observed for the lower PBDEs.     

Heavy metals in water and in tissues of himri (Carasobarbus luteus) from Orontes (Asi) River, Turkey

Concentrations of heavy metals (Ag, Cd, Cr, Cu, Fe, Ni, Pb ve Zn) were measured in running water and in tissues (muscle, liver, gill, skin and gonads) of one commercially valuable fish species (Carasobarbus luteus) from the Orontes (Asi) River (Güzelburç region) in Hatay (Southeastern Turkey). Results for levels in water compared with national and international water quality guidelines were found at the highest concentrations in international criteria’s WHO, EC and EPA, but Cd, Cu, Ni and Pb were found to exceed permissible level of drinking water in national criteria TSE-266 whereas Fe, Zn and Cr concentrations were within the permissible levels for drinking. The present study showed a significant seasonal variation (p?p?>?0.05), which showed seasonal variation of only Zn (p?C. luteus were below the permissible limit for human consumption, level of Cu being very close to the permissible limit. Consequently, continuous monitoring of heavy metal concentration in edible freshwater fish will be needed in Orontes River.     

Residual fate and persistence of endosulfan (50 WDG) in Bengal gram (Cicer arietinum)

A detailed study has been presented on heavy metal content of the Iture Estuary. Waters of the Sorowie and Kakum rivers that supply water into the Estuary were investigated to ascertain heavy metal pollution levels due to anthropogenic activities. Concentration s of Cd, Zn, Se and Pb were measured. The study shows pre-occupying pollution levels that constitute a threat to both terrestrial and aquatic ecosystems. The abundance of metals in the Estuary is in the order Zn > Pb > Cd > Se. The level of Cd in the Iture Estuary ranged between 0.011 mg/l and 0.041 mg/l while Se was in the range 0.018 mg/l to 0.029 mg/l, Pb 0.020 mg/l to 0.075 mg/l and Zn 0.040 to 2.45 mg/l. The impact of contaminated water from the Sorowie River on the Iture Estuary was outstanding and the study points out the importance of the Sorowie River as a primary pollution source to the Iture Estuary. The pollution of the Iture Estuary was found to be connected to human activities in its catchments.     

Concentrations of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in vacuum cleaner dust collected in Japanese homes

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are shown to be globally distributed, environmentally persistent and bioaccumulative. Although there is evidence that these compounds exist in the serum of non-occupationally exposed humans, the pathways leading to the presence of PFOS and PFOA are not well characterized. The concentrations of PFOS and PFOA in the vacuum cleaner dust collected in Japanese homes were measured. The compounds were detected in all the dust samples and the ranges were 11-2500 ng g(-1) for PFOS and 69-3700 ng g(-1) for PFOA. It was ascertained that PFOS and PFOA were present in the dust in homes, and that the absorption of the dust could be one of the exposure pathways of the PFOS and PFOA to humans. With regard to risk management, it is important to consider the usage of PFOS and PFOA in the indoor environment in order to avoid further pollution.     

电感耦合等离子体质谱法测定饮用水中的硒

应用电感耦合等离子体质谱法测定饮用水中的硒元素。结果表明,高能碰撞模式(HEHe)较碰撞/反应池气体模式(He模式)消除干扰效果更好;在HEHe模式下,~(78)Se在0.5~100μg/L范围内线性良好,相关系数0.999 9,方法检出限为0.06μg/L,相对标准偏差为0.4%~0.8%,加标回收率为97.1%~103.2%。方法性能指标均能较好满足饮用水中Se的定量测试要求。     

Occurrence of haloacetic acids (HAAs) and trihalomethanes (THMs) in drinking water of Taiwan

In this study, water samples were collected from 86 water treatment plants for analysis of haloacetic acids (HAAs) and trihalomethanes (THMs) from February to March, 2007 and from July to August, 2007. Both seasonal and geographical variations of disinfection by-products (DBPs) in drinking water of Taiwan were presented. The results showed that the five HAA concentrations (HAA5) were 1.0–38.9 μg/L in the winter and 0.2–46.7 μg/L in the summer; and the total THMs were ND-99.4 μg/L in the winter and ND-133.2 μg/L in the summer. For samples taken from the main Taiwan island, dichloroacetic acid (29.4–31.7%) and trichloroacetic acid (25.3–27.6%) were the two major HAA species, and trichloromethane was the major THM species (49.9–62.2%) in finished water. For water treatment plants located on the offshore islands outside of Taiwan, high bromide concentration was found in raw water, and higher percentage of brominated THMs and HAAs were formed in the overall formation. A statistically significant (P?<?0.005) logarithmic linear regression model was found to be useful to describe the correlations between TTHM and HAA5 or nine HAAs (HAA5?=?1.219 ×TTHM ^0.754, R ²?=?0.658; HAA9?=?1.824 ×TTHM ^0.735, R ²?=?0.678). No apparent difference was observed for DBPs concentrations between finished water and distribution samples in this study.     

测定电镀废水中铬(Ⅵ)的新光度法

在硝酸介质中,二甲基黄先显色而后在加热条件下褪色,铬( )能显著阻抑此褪色反应,且阻抑程度与铬( )含量相关,据此建立了测定痕量铬( )的新方法。方法检出限是1.55×10-10g/ml,线性范围0.1～1.2μg/10ml,用于电镀废水中铬( )的测定,结果满意。     

Determination of Pb(II), Zn(II), Cd(II), and Co(II) ions by flame atomic absorption spectrometry in food and water samples after preconcentration by coprecipitation with Mo(VI)-diethyldithiocarbamate

A new, simple, and rapid separation and preconcentration procedure, for determination of Pb(II), Cd(II), Zn(II), and Co(II) ions in environmental real samples, has been developed. The method is based on the combination of coprecipitation of analyte ions by the aid of the Mo(VI)–diethyldithiocarbamate–(Mo(VI)-DDTC) precipitate and flame atomic absorption spectrometric determinations. The effects of experimental conditions like pH of the aqueous solution, amounts of DDTC and Mo(VI), standing time, centrifugation rate and time, sample volume, etc. and also the influences of some foreign ions were investigated in detail on the quantitative recoveries of the analyte ions. The preconcentration factors were found to be 150 for Pb(II), Zn(II) and Co(II), and 200 for Cd(II) ions. The detection limits were in the range of 0.1–2.2 μg L^?1 while the relative standard deviations were found to be lower than 5 % for the studied analyte ions. The accuracy of the method was checked by spiked/recovery tests and the analysis of certified reference material (CRM TMDW-500 Drinking Water). The procedure was successfully applied to seawater and stream water as liquid samples and baby food and dried eggplant as solid samples in order to determine the levels of Pb(II), Cd(II), Zn(II), and Co(II) ions.