Endocrine disrupting activity in fruits and vegetables evaluated with the E-screen assay in relation to pesticide residues

Food is likely to be one of the most important routes of human exposure to endocrine disrupting compounds (EDCs). In the present study, we evaluated the total estrogenic activity of fruits and vegetables, which was calculated using the human breast cancer cell line (MCF-7 BUS) proliferation assay (E-screen), in relation to pesticide residues. We analysed 44 food samples, 30 fruits and 14 vegetables. Of these samples, 10 did not contain any pesticide residues. The other 34 samples contained from 1 to 7 pesticide residues in concentrations ranging from 0.03 to 1.91 ppm. Estrogenic activity was detected in the 59% of samples tested. The positive controls used were 17-β-estradiol (E2), the phytoestrogen genistein and the pesticide endosulfan. The average value of estradiol equivalency quantity (EEQ) for all positive samples was 0.15±0.32 μg/100g. A low correlation was found between the concentration of pesticide residues and the EEQ values (Spearman correlation r=0.376 and p=0.012). Using values obtained from the literature, we compared the estrogenic activity of food samples with the intrinsic content of phytoestrogens, but we found no correlations. Our results also suggested that the calculated intake of dietary EDCs might represent a concentration comparable to the normal endogenous estrogen concentration in human blood.     

Influence of tillage on soil macropore size, shape of top layer and crop development in a sub-humid environment

Topsoil macropores of two plots under no-tillage and conventional tillage were analyzed. A leguminous-cereal rotation was applied for six cycles under dry-land farming system (crop residues were removed). The clay-loam soil shows some vertic characteristics. The main goal is to identify the relationship between the top soil macro and meso-pore distribution for the two tillage systems (at the end of sixth cycle of cultivation) with the annual crop production (rainfall in normal growing period and crop production values are included). Unaltered topsoil samples were taken from 0 to 60 mm (row and interrow positions) and from the immediate depth (60 to 110 mm) in both plots (conventional and no-tillage). The morphometric analyses of 66 polished slices were carried out with the aim to identify differences in soil macro and meso-pore organisation. Soil macropores were classified by size (area) and elongation ratio and by form factor and equivalent pore diameter. No appreciable differences were observed. Soil macro and meso-pore distributions of samples were also compared. The main difference observed between topsoil’s treatments was a different macropore size distribution between topsoil positions. The presence of larger macropores was higher in conventional tillage compared to no-tillage. Samples taken from row and deeper positions of conventional tillage show a somewhat higher amount of macropores in the range between 2 to 2.3 mm equivalent pore diameter. Soil macropores contribute to increase soil aeration and soil drying when topsoil is too wet in critical periods of crop development. Conventional tillage (crop residues removed), provides to the topsoil of a larger lateral and vertical variability of macropore distribution than no-tillage topsoil.     

Analysis of Some Pesticide Residues in Tomatoes in Ghana

Pesticide residues, both natural and synthetic, can be found in most of the things we eat, for example, fruits, vegetables, bread, meat, poultry, fish, and the processed foods made from them. Some of this pesticide contamination is legal, but does this mean it is safe? Much of it is illegal, with residues found in excess of regulatory safe levels. Identifying and determining the level of trace contaminants in our food and environment is critical in protecting and improving human health and the environment. This study evaluates the residue levels of select pesticides used on tomato crops in Ghana that are likely to have accumulated in the tomatoes during application. The results obtained confirm that pesticide residues were indeed present in the tomatoes and further analysis quantified the amount present. Analysis of some organochlorine and organophosphorus residue levels in the fruits indicated that chlorpyrifos, which is an active ingredient of pesticides registered in Ghana under the trade name dursban 4E or terminus 480 EC for use on vegetables, has the greatest residue level of 10.76 mg/kg. The lowest residue level observed was that of pirimiphos-methyl with 0.03 mg/kg. Human health risk assessment was performed on the results obtained from the analysis using Human Health Evaluation computerized software-RISC 4.02. The risk assessment showed cancer risk for adults and children due to the presence of endosulfan and chlopyrifos. Endosulfan is not registered in Ghana as a pesticide for use on vegetables, therefore the detection of endosulfan in several samples indicates misuse of agrochemicals among Ghanaian farmers.     

Advances of organic products over conventional productions with respect to nutritional quality and food security

Organic products are derived from the organic production system, following organic agricultural cultivation standards, and processing schedules must be identified by an independent certificate authority. The main characteristic of the organic agricultural production system is that all artificial synthetic materials such as pesticides, fertilizers, growth regulators, feed additives, and gene engineering products are not allowed to use. However, there is much debate on organic production quality and health safety issues in academic circles. Some people believe that there is a “Three Cannot” problem with organic production, that is, organic products “cannot be distinguished, cannot be tasted and cannot be measured” compared to common ones. To objectively reflect the differences in nutritional quality and food safety between organic and conventional products, we combined extensive literatures with our research data and have reported some advances in the sensory quality, nutritional value, and safety of the two types of products. The results showed that organic products tasted better; the percentage of leanness was higher, and the products tasted much tender. The dry matter content of most organic crops was about 7–20% higher than that of conventional foods, and enriched vitamin C, anthocyanins, isoflavones, carotenoids, and other phenolic compounds and more elements such as P, Fe, and Mg and trace elements such as Zn, Cu, and Cr were verified in organic crops. Organic animal products contain more beneficial polyunsaturated fatty acids; the nitrate content in organic fruits and vegetables was 20–50% of that in normal fruits. No pesticide residues and less heavy metals were found in the organic products. Our investigation showed that there were obvious differences in quality and safety between the products that originated from organic agriculture systems and conventional alternatives. This conclusion can provide an important theoretical basis for the healthy development of the organic industry.     

Overview of pesticide residues in stored pollen and their potential effect on bee colony (Apis mellifera) losses in Spain

In the last decade, an increase in honey bee (Apis mellifera L.) colony losses has been reported in several countries. The causes of this decline are still not clear. This study was set out to evaluate the pesticide residues in stored pollen from honey bee colonies and their possible impact on honey bee losses in Spain. In total, 1,021 professional apiaries were randomly selected. All pollen samples were subjected to multiresidue analysis by gas chromatography-mass spectrometry (MS) and liquid chromatography-MS; moreover, specific methods were applied for neonicotinoids and fipronil. A palynological analysis also was carried out to confirm the type of foraging crop. Pesticide residues were detected in 42% of samples collected in spring, and only in 31% of samples collected in autumn. Fluvalinate and chlorfenvinphos were the most frequently detected pesticides in the analyzed samples. Fipronil was detected in 3.7% of all the spring samples but never in autumn samples, and neonicotinoid residues were not detected. More than 47.8% of stored pollen samples belonged to wild vegetation, and sunflower (Heliantus spp.) pollen was only detected in 10.4% of the samples. A direct relation between pesticide residues found in stored pollen samples and colony losses was not evident accordingly to the obtained results. Further studies are necessary to determine the possible role of the most frequent and abundant pesticides (such as acaricides) and the synergism among them and with other pathogens more prevalent in Spain.     

Evaluation of selected plant growth regulators and fungicide residues in fruits for dietary risk assessment

A total of 96 samples of fresh fruits were collected to investigate the residues of selected plant growth regulators and fungicides. The analyses utilized ultra-high-performance liquid chromatography coupled with tandem mass spectrometry after a modified QuEChERS method. The results were evaluated according to maximum residue limits (MRLs) by the Chinese regulation. All blueberries, litchis, and watermelons were pesticide-free, and only one (1%) fruit sample contained pesticide residues above MRLs. Concerning the most frequently detected pesticide residues, carbendazim was found in 20% of the samples analyzed. Data obtained were then used to estimate the potential health risks associated with the exposures to these pesticides. The short-term risks were below 3.25% and the long-term risks were also very low, ranging from 0.0005% for dimethomorph to 0.4302% for prochloraz.     

Organochlorine Pesticide Residues in Human Fat in the United Kingdom 1969-71

During the period 1969-71 samples of human body fat were taken during routine necropsies on 201 subjects over 5 years old and 20 stillborn babies and infants under 5 years old, and analysis was carried out for organochlorine pesticide residues. By comparing the results from this period with those from similar studies undertaken in 1963-4 and 1965-7, it is clear that a downward trend continues.     

Organochlorine pesticide residues in human fat in the United Kingdom 1976-7.

Between May 1976 and August 1977 samples of human body fat were taken during routine necropsies in the United Kingdom on 236 subjects aged over 5 years and four infants aged under 4 months. Comparison with results from earlier studies showed a further decline in residues of pp''-dichlorodiphenyltrichloroethane (pp''-DDT) and dieldrin (HEOD) and increased amounts of hexachlorobenzene residues; concentrations of other compounds were similar to those observed in the studies carried out in 1963-4, 1965-7, and 1969-71. Comparison of the data with those from other countries, showed that the concentrations of organochlorine pesticide residues and polychlorobiphenyls in human fat samples from residents of the United Kingdom remain among the lowest in Europe and, indeed, the world.     

Consumer Risk Assessment Associated with Intake of Pesticide Residues in Food of Plant Origin from the Retail Market in Poland

The aim of this study was to characterize short- and long-term risk for consumers associated with dietary intake of pesticide residues in fruits, vegetables, and other foodstuffs available on the Polish market based on 2010–2013 official surveillance results. Among 779 samples collected from 2010 to 2013 no pesticide residue was found in 39.7% samples while 58.5% contained residues at or below the EU Maximum Residue Levels (MRLs). Non-compliances (residues above the respective MRLs) were found in 14 samples (1.8%). Most of the estimated daily intakes were well below 1% of respective acceptable daily intake (ADI) values. The highest intake for children and adults was about 7% and 1.5% of ADI, respectively. For non-compliant results acute risk was characterized. Predicted short-term intakes for children and adults ranged from 0.7% to 425%, and from 0.2% to 100% of respective acute reference dose, respectively. Results of chronic risk characterization show that consumers in Poland are adequately protected; however, incidental cases where residue levels may potentially pose a threat to consumers’ health due to acute exposure cannot be excluded.     

Pesticide Residues in Agricultural Produce in Hubei Province,PR China

Pesticide residues in agricultural produce were examined in two villages of Qianjiang municipality, Hubei province, PR China. Six food groups were sampled from the fields prior to harvesting from the farmers' market and from farmers' homes. Organochlorine residues were detected in almost all examined food groups, with residue levels significantly lower than the national tolerances (MRL). Total BHC residues were on average 31.7?µg/kg and DDT 102.5 (µg/kg. Organophosphorus residues were detected in vegetable samples. Mean residue levels of phoxim and methamidophos in vegetables were 89.9?µg/kg and 36.5?µg/kg, respectively, both exceeding the MRL. Estimated daily intakes (EDIs) of pesticide residues per person, based on the six food groups sampled, were 4.88?mg for total DDT, 2.04 (µg for total BHC, and 19.33 (µg for methamidophos. The overall results show that the increased use and misuse of pesticides for crop protection in Qianjiang municipality, notably in vegetable production, have led to worrisome levels of pesticide contamination of agricultural produce that may carry certain risks for human health.     

The soil macrofauna and organochlorine insecticide residues at twelve agricultural sites near Huntingdon

Ten arable fields and two apple orchards were chosen from a total of thirty-five sites visited to represent typical soils, crop rotations and insecticide applications in the Huntingdon area of East Anglia. Pitfall traps were used to collect insects and other invertebrates during fortnightly periods from early April until harvesting and in one orchard until the following February. Estimates of active biomass were obtained for several groups of invertebrates and differences between the sites are discussed. Samples of beetles, earthworms and slugs were collected during June and were sent with soil samples to the Government Chemist for analysis of organochlorine residues. The soil residues are compared with those in respective invertebrate samples and with stated application rates. It is concluded that soil invertebrates could form a regular source of pesticide residues for ground-feeding birds but that the levels are generally too low to cause acute poisoning.     

Evaluation of meat products from cloned cattle: biological and biochemical properties

Agricultural utilization of cloned livestock produced by nuclear transfer and their products for food will require public and governmental acceptance. A series of studies of properties of meat derived from cloned cattle was carried out to collect data for the safety assessment of cloned cattle products. Meat samples obtained from embryonic cloned, somatic cloned and non-cloned cattle were analyzed for chemical composition, as well as amino acids and fatty acids. Digestibility, allergenicity, and mutagenicity of meat were also examined. There were no significant differences in these properties among embryonic cloned, somatic cloned and non-cloned cattle. The analyses and tests revealed that there were no significant biological differences in meat from a non-cloned, an embryonic cloned, or a somatic cloned animal. A 14-week feeding trial in rats showed there were no abnormalities in body growth, general condition, locomotor activity, reflexes, sexual cycle, urinalysis, hematology, blood biochemistry, and histology. This study showed for the first time that the biological/biochemical properties of meat of cloned cattle are similar to those of non-cloned cattle.     

DNA extraction from soil: comparison of different methods using spore-forming bacteria and theswrAA gene as indicators

Soil microcosms seeded with spores of a tracer organism (Bacillus subtilis strain PB5332) were used to test five different DNA extraction protocols hereby indicated as A, B, C, D and E. The representativity of DNA samples obtained from each procedure was evaluated by PCR amplification of theswrAA gene, unique to PB5332 strain, followed by Southern hybridization with a gene-specific probe. A significant improvement of DNA extraction from spores was obtained using grinding under liquid N2 associated with sodium-dodecyl sulphate (SDS)-based lysis in presence of 1% hexadecyltrimethylammonium bromide (CTAB; protocol C). The same procedure was tested on soil samples from two distinct greenhouse trials carried out with genetically modified white poplars (Populus alba L) expressing theStSy gene for resveratrol production and thebar gene for Basta® tolerance, respectively. The representativity of DNA samples recovered from the greenhouse soil was assessed using three spore-forming bacteria (SFB) as tracer organisms. The tracers (SFB-1, SFB-2 and SFB-3) were previously isolated from the same trials classified as members of the genusBacillus. All the tested DNA samples produced the expected amplification products, indicating the presence at the soil level of the tracers and confirming the reliability of the optimized DNA extraction protocol.     

Toxicological evaluation of multi-class pesticide residues in vegetables and associated human health risk study for adults and children

This article describes, for the first time in 10 years, the toxicological evaluation of pesticide residues in highly consumed vegetables (35 commodities) and health risk studies. Among 1075 vegetable samples consisting mainly of tuber, root, fruiting, and Brassica, 20% of samples contained 38 pesticides in the range of 0.005–18.7 mg/kg and 1% > maximum residue limits (MRLs). Organophosphates and chloronitrile were most frequently found (20%) in the pesticide class. The highest concentration of 18.7 mg/kg was noted for dichlofluanid. Fruiting vegetables (8%), especially tomatoes (5%), were the most contaminated, while multi-residues were determined in 5% of the samples. Risk assessment was performed by analytical results and consumption on the 97.5 percentile expressed as hazard index (HI) and hazard quotient (HQ). The highest chronic HI was calculated for diazinon in lettuce (32% Acceptable Daily Intake (ADI) adults and 36% children) and for forbidden dieldrin in carrots (26%, 62% ADI). The highest acute HI was estimated for dichlofluanid in lettuce (69% Acute Reference Dose (ARfD)) for adults, whereas for children it was above the acceptance values of ARfD (168%). Organophosphate insecticides with common mode of action showed the greatest HQ (108% ADI). Vegetables may not be a serious problem for consumers, but investigations on pesticide residues are necessary to ensure food safety and the protection of human health, especially toward children who are more highly exposed to pesticides than adults.     

Exploration of disorder in protein structures by X-ray restrained molecular dynamics

Conformational disorder in crystal structures of ribonuclease-A and crambin is studied by including two independent structures in least-squares optimizations against X-ray data. The optimizations are carried out by X-ray restrained molecular dynamics (simulated annealing refinement) and by conventional least-squares optimization. Starting from two identical structures, the optimizations against X-ray data lead to significant deviations between the two, with rms backbone displacements of 0.45 A for refinement of ribonuclease at 1.53 A resolution, and 0.31 A for crambin at 0.945 A. More than 15 independent X-ray restrained molecular dynamics runs have been carried out for ribonuclease, and the displacements between the resulting structures are highly reproducible for most atoms. These include residues with two or more conformations with significant dihedral angle differences and alternative hydrogen bonding, as well as groups of residues that undergo displacements that are suggestive of rigid-body librations. The crystallographic R-values obtained are approximately 13%, as compared to 15.3% for a comparable refinement with a single structure. Least-squares optimization without an intervening restrained molecular dynamics stage is sufficient to reproduce most of the observed displacements. Similar results are obtained for crambin, where the higher resolution of the X-ray data allows for refinement of unconstrained individual anisotropic temperature factors. These are shown to be correlated with the displacements in the two-structure refinements.     

Deinking of laser printed copy paper with a mediated free radical system

This work investigated the effect of a chelator-mediated bio-mimetic free radical treatment on repulping and flotation operations during the deinking of laser printed copy paper. A chelator-mediated free radical treatment was carried out at two different chemical levels and a two-step repulping method, which combined conventional alkaline repulping as well as free radical treatment, was also developed. Flotation trials were performed on each of these treated samples to separate ink particles. Results from image analysis and paper physical properties testing are presented, and the deinking efficiency for these different treatments is also compared. Results indicate that under properly controlled conditions, free radical treatment can perform better than conventional chemical deinking methods.     

Quantitative proteomics by 2DE and MALDI MS/MS uncover the effects of organic and conventional cropping methods on vegetable products

Organic farming aims to be environmentally sound, but the question as to whether organic cropping brings more nutritional benefits to farmers and consumers than the conventional cropping needs still to be answered. To gain insights into the molecular effects of organic farming we used proteome analysis to analyze cabbage (Brassica oleracea L. var 'capitata') and carrot (Daucus carota var. 'sativus') Our aim was to identify the metabolic pathways that are affected by different cropping regimes and thus, may have an effect on quality, storability and pathogen resistance of crops. By means of two dimensional gel electrophoresis and MALDI tandem mass spectrometry we compared proteomes of cabbage and carrot root, obtained in the first growth season, cropped under three different schemes. These included a conventional scheme (C) and two organic schemes, O1, in which nutrients were delivered in a form of slurry, in accordance to regulations of organic farming and O2, in which nutrient supply was based mainly on autumn green manures. Proteins were extracted from lyophilized plant tissues into a buffer containing high concentrations of urea/thiourea, two detergents and reducing agent. This approach allowed short handling times of fresh plant materials. In the case of cabbage samples, the abundance levels of 58 out of more than 1300 quantified protein spots varied significantly between conventional farming and any of the organic cropping systems. Proteome profiles were also very similar between carrot root samples, where 68 out of 1800 resolved protein spots varied significantly. Proteins of the glycolytic pathway and Krebs cycle as well as several proteins related to amino acid and protein metabolism were overexpressed in organically farmed cabbage. Proteins related to detoxification processes were overexpressed in conventionally grown cabbage. Proteins involved in metabolism of carbohydrates, polypeptides and secondary metabolites were affected by different cropping regimes in carrots. The proteomes of conventionally grown vegetables varied from organically grown vegetables to a larger extent than the two organic cropping schemes varied from each other. In conclusion, this proteomics platform is suitable and useful for systematic studies of the effects of organic and conventional farming techniques on plant metabolism.     

Quick and Label-Free Detection for Coumaphos by Using Surface Plasmon Resonance Biochip

Coumaphos is a common organophosphorus pesticide used in agricultural products. It is harmful to human health and has a strictly stipulated maximum residue limit (MRL) on fruits and vegetables. Currently existing methods for detection are complex in execution, require expensive tools and are time consuming and labor intensive. The surface plasmon resonance method has been widely used in biomedicine and many other fields. This study discusses a detection method based on surface plasmon resonance in organophosphorus pesticide residues. As an alternative solution, this study proposes a method to detect Coumaphos. The method, which is based on surface plasmon resonance (SPR) and immune reaction, belongs to the suppression method. A group of samples of Coumaphos was detected by this method. The concentrations of Coumaphos in the samples were 0 µg/L, 50 µg/L, 100 µg/L, 300 µg/L, 500 µg/L, 1000 µg/L, 3000 µg/L and 5000 µg/L, respectively. Through detecting a group of samples, the process of kinetic reactions was analyzed and the corresponding standard curve was obtained. The sensibility is less than 25 µg/L, conforming to the standard of the MRL of Coumaphos stipulated by China. This method is label-free, using an unpurified single antibody only and can continuously test at least 80 groups of samples continuously. It has high sensitivity and specificity. The required equipments are simple, environmental friendly and easy to control. So this method is promised for a large number of samples quick detection on spot and for application prospects.     

Bacterial pollution of Messina coastal waters: a one year study

A year's monitoring of faecal pollution of marine coastal waters surrounding Messina was carried out in 1996/97. The distribution of faecal coliforms was evaluated in 15 stations located along the Sicilian coastline, sampled monthly in coincidence of the two opposing current phases ("montante" and "scendente" currents) which characterise the Straits of Messina. The data obtained provided a complete picture of hygienic-sanitary conditions of the area and highlighted the presence of heavily polluted sites in correspondence with river outflows. Higher bacterial counts were associated with lower salinity values and higher ammonia concentrations; over an annual study, they occurred during the coldest months, showing the negative impact of continental water inputs on the bacteriological quality of coastal waters.     

Development of a Freeze-Dried Fungal Wettable Powder Preparation Able to Biodegrade Chlorpyrifos on Vegetables

Continuous use of the pesticide chlorpyrifos has resulted in harmful contaminations in environment and species. Based on a chlorpyrifos-degrading fungus Cladosporium cladosporioides strain Hu-01 (collection number: CCTCC M 20711), a fungal wettable powder preparation was developed aiming to efficiently remove chlorpyrifos residues from vegetables. The formula was determined to be 11.0% of carboxymethyl cellulose-Na, 9.0% of polyethylene glycol 6000, 5.0% of primary alcohol ethoxylate, 2.5% of glycine, 5.0% of fucose, 27.5% of kaolin and 40% of freeze dried fungi by response surface methodology (RSM). The results of quality inspection indicated that the fungal preparation could reach manufacturing standards. Finally, the degradation of chlorpyrifos by this fungal preparation was determined on pre-harvest cabbage. Compared to the controls without fungal preparation, the degradation of chlorpyrifos on cabbages, which was sprayed with the fungal preparation, was up to 91% after 7 d. These results suggested this freeze-dried fungal wettable powder may possess potential for biodegradation of chlorpyrifos residues on vegetables and provide a potential strategy for food and environment safety against pesticide residues.