Organophosphorus pesticide residues in Greek virgin olive oil: levels,dietary intake and risk assessment

The occurrence of organophosphorus pesticide (OPs) and their metabolite residues was investigated in 167 samples of Greek virgin olive oil during a 2-year (2004–2005) sampling campaign. A total of 30.5% of samples contained detectable residues, although only one sample contained dimethoate residues above the maximum residue limit. Among the seven detected OPs, fenthion and fenthion sulfoxide residues were detected in 10.8 and 14.4% of the samples, respectively, at levels of 0.003–0.61 mg kg^?1. Dimethoate was detected in 10.2% of the samples at 0.003–0.057 mg kg^?1. The acute dietary risk assessment was undertaken by determining the national estimated short-term intake (NESTI); for chronic dietary risk assessment, the national theoretical maximum daily intake (NTMDI) and national estimated daily intake (NEDI) were calculated. The estimated intakes (NESTI and NEDI) of each pesticide were <7 and <0.86% of the corresponding acute reference doses (ARfDs) and acceptable daily intakes (ADIs), respectively. A cumulative risk assessment was performed using the hazard index (HI) and toxicity equivalence factor (TEF), taking into account that OPs share the same toxicological mechanism. The determined HI and TEF values were found to represent only a small portion of the respective ADIs or ARfDs. These results indicate that there is neither acute nor chronic risk for the Greek population through olive oil consumption.     

Pesticide residue assessment in different types of olive oil and preliminary exposure assessment of Greek consumers to the pesticide residues detected

In this study the occurrence and levels of multi-class pesticides in different types of virgin olive oil quality and origination were determined and the contribution of olive oil in the chronic risk of pesticide residues consumption in the Mediterranean diet was estimated. For this purpose, a multiresidue method for the determination of 35 pesticides in olive oil was evaluated and applied to a total number of 100 olive oil samples. Ten percent of the samples produced from fruits of conventional cultivations contained no detectable residues whereas in the rest samples were detected residues of 20 insecticides. The highest detection rates were observed for the residues of fenthion, dimethoate and endosulfan. The highest occurrence and levels of pesticides were observed in extra virgin olive oil whereas results pointed that residues in olive oil from variety of olives with high oil yield may be higher. Furthermore, olive oil from organic cultivations could be contaminated with pesticide residues and/or contain low levels of pesticide residues that are not registered for use in olive cultivations. For there were multiresidues of pesticides present in olive oil, there is no zero risk in consumption of olive oil. However, the exposure of olive oil consumers to each detected residue is far below the acceptable daily intake (ADI).     

Organophosphorus pesticide residues in milled rice ( Oryza sativa ) on the Chinese market and dietary risk assessment

The present study investigates the occurrence of acetylcholinesterase (AChE)-inhibiting organophosphorus (OP) pesticide residues in milled rice samples obtained form local markets in China during the period 2004–2006 and estimates their cumulative exposure. Concentrations of OP pesticides were determined by gas chromatography with flame photometric detection (GC–FPD). The results showed that 9.3% of the samples contained detectable residues of at least one of the seven target OP pesticides (chlorpyrifos, dichlorvos, omethoate, methamidophos, parathion-methyl, parathion and triazophos) mainly used for agriculture in China, with concentrations ranging 0.011–1.756 mg kg^?1. Rice consumption data was obtained from an individual food consumption survey. Relative potency factors (RPFs) for each pesticide were calculated with methamidophos as the index compound (IC), using 1- or 2-year chronic non-observed adverse effect levels (NOAEL) for AChE inhibition, mostly in rat brain, obtained from international evaluations of pesticides. Exposure to AChE-inhibiting pesticides for the population above 7 years old at P99.9 represented 52–94.5% of the acceptable daily intake (ADI) expressed as methamidophos. Estimated exposure for children aged 2–4 and 4–7 years at P99.9 were 119 and 104.3% of the ADI level, respectively. This study suggests that a yearly monitoring program for OP pesticide residues and strict implementation of the national safety standard for milled rice is necessary.     

Survey of organophosphorus pesticide residues in virgin olive oils produced in Chile

Dimethoate, diazinon, parathion methyl, pirimiphos methyl, malathion, fenthion, chlorpyriphos, methidathion and azinphos methyl were determined in 71 olive oil samples produced in Chile from different varieties of olives (arbequina, frantoio, picual, lechino and blend) at three different harvest periods (2007, 2008 and 2009). The target pesticides were determined using a validated analytical method based on microwave-assisted liquid–liquid and solid-phase extraction with subsequent GC–FPD detection and GC–MS/MS for confirmation purposes. In 79% of the samples, five of the nine pesticides tested were detected with a frequency of one pesticide per sample. The highest detection rates were observed for the residues of chlorpyriphos and diazinon. The average concentration of chlorpyriphos, diazinon, azinphos methyl and methidathion were 0.084, 0.057, 0.024 and 0.010 µg g^?1, respectively. Higher contents of organophosphorus pesticides (OPPs) were found in regions where intensive agriculture is practiced. However, the levels of OPPs were reassuringly low and indicate that olive oil produced and exported from Chile does not currently represent any risk for consumers.     

Survey of pesticide residues in table grapes: Determination of processing factors, intake and risk assessment

The differences in residue pattern between Italy and South Africa, the main exporters of table grapes to the Danish market, were investigated. The results showed no major differences with respect to the number of samples with residues, with residues being found in 54-78% of the samples. Exceedances of the European Union maximum residue limit (MRL) were found in five samples from Italy. A number of samples were rinsed to study the possible reduction of residues. For copper, iprodione, procymidone and dithiocarbamates a significant effect of rinsing was found (20-49% reduction of residues). However, no significant effect was found for organophosphorus pesticides and pyrethroids, whereas the number of samples with residues of benzilates, phenylamids and triazoles was insufficient to demonstrate any significant effects. An intake calculation showed that the average intake from Italian grapes was 3.9 µg day^-1 for pesticides and 21 µg day^-1 for copper. Correspondingly, the intakes from South African grapes were 2.6 and 5.7 µg day^-1, respectively. When the total exposure of pesticides from grapes were related to acceptable daily intake, expressed as the sum of Hazard Quotients, the exposure were approximately 0.5% for Italian samples and 1% for South African samples.     

Unit to unit variation of pesticide residues options for acute dietary risk assessment

Within the context of the current UK policy for those commodities where the potential variability of residues in individual commodity units is taken into account, a variability factor nu , which reflects the ratio of a high level residue in the individual commodity unit to the corresponding composite residue level, is used. Data gathered from supervised industry trials in which individual items were analysed following treatment, although limited, show that variability is typically lower than that reflected by the default factors currently used and that the range of variability is reproducible over the limited range of different a.i./crop/method of application combinations investigated. In order to improve the accuracy of the acute dietary exposure estimate, the European Crop Protection Association (ECPA) proposes the following alternative to the current Tier I approach. The residue level input from a 'hot' unit within the dietary risk assessment should be determined using the highest composite sample residue from supervised field trials and a generic variability factor (nu) determined experimentally from supervised trials. The variability factor itself should be calculated as the 95th percentile level of the residue level found in an individual unit (or single serving portion for large crops) divided by sample mean for data produced from supervised trials. This would improve the accuracy of the Tier I approach and allow attention to be focused on particular a.i./crop/method of application combinations where the NESTI> acute RfD (based on a Tier I assessment) and generation of individual unit residue data for the particular outlet or other mitigation may be appropriate.     

Direct analysis of glucuronidated metabolites of main olive oil phenols in human urine after dietary consumption of virgin olive oil

In the present study we report on a UPLC-MRM validated method for the simultaneous direct analysis of main glucuronidated metabolites of olive oil phenols: tyrosol, hydroxytyrosol and its O-methyl metabolite homovanillyl alcohol in human urine after dietary olive oil ingestion. The developed method was linear within the concentration range 20–2000 ng/mL with adequate recovery of analytes (>86%). Intra- and inter-day precision and accuracy were according to standard requirements for method validation criteria. Using the developed method, urinary concentrations and excretion rates of glucuronides of olive oil phenols were successfully estimated in an intervention study with 11 healthy volunteers supplemented with a dietary dose of virgin olive oil (VOO) (50 mL). Therefore, about 13% of the consumed olive oil polyphenols were recovered in 24-h urine, where 75% of them were in the form of glucuronides (3′- and 4′-O-hydroxytyrosol glucuronides, 4′-O-glucuronides of tyrosol and homovanillyl alcohol) and 25% as free compounds.     

Geographical classification of Greek virgin olive oil by non-parametric multivariate evaluation of fatty acid composition

Fatty acid compositional data for Greek virgin olive oils from 24 years of harvest and various regions and cultivars were evaluated using chemometric methods. Non-parametric discriminant analysis after proper transformation of the data seems to be a suitable approach to characterise the oils according to the geographical origin and may produce a scientific basis for the assignment of an ‘appellation d'origine’ trade mark.     

Organophosphorus pesticide residues in market foods in Shaanxi area,China

The aim of this study was to investigate the organophosphorus (OP) pesticide residues in market foods (cereals, vegetables, and fruits) in the Shaanxi area of China. The concentrations of eight OP pesticides were determined by gas chromatography with flame photometric detection (GC-FPD). In 18 of 200 samples, five OP pesticides, including dichlorvos, dimethoate, parathion-methyl, pirimiphos-methyl and parathion, were found in concentrations ranging from 0.004 to 0.257 mg/kg. The mean levels of dimethoate in fruits and parathion in vegetables exceeded the maximum residue limits (MRLs) allowed by the Ministry of Health, of China. Other detectable OP pesticide residues levels were below their MRLs. Demeton, diazinon and sumithion were not found in any sample. The results provide important information on the current contamination status of a key agricultural area in China, and point to the need for urgent action to control the use of some excessively applied and potentially persistent OP pesticides, such as dimethoate and parathion.     

Polychlorinated biphenyls, hexachlorobenzene, hexachlorocyclohexane isomers, and pesticide organochlorine residues in cod-liver oil dietary supplements

Levels of polychlorinated biphenyls (PCBs), hexachlorobenzene, hexachlorocyclohexane isomers (alpha, beta, gamma), and chlorinated pesticides (DDTs) in cod-liver oil used as a dietary supplement were determined. Total PCB and DDT concentrations varied from 25 to 201 ng g(-1) lipid weight basis and from 25 to 133 ng g(-1) lipid weight basis, respectively. Hexachlorobenzene contributed very little to the overall contaminant burden of dietary supplement oils, whereas hexachlorocyclohexane isomers were below the instrumental detection limits in all samples. The daily intake of PCBs and DDTs derived by the consumption of cod-liver oil at manufacturer-recommended doses varied from 0.004 to 2.01 microg/day and from 0.004 to 1.24 microg/day, respectively. Relative to some dioxin-like PCB congeners (mono-ortho PCB 105, 118, and 156; non-ortho PCB 77, 126, and 169), the intakes calculated varied from less than 0.001 to 0.74 pg of toxic equivalency values (TEQ) per kg of body weight per day. These values, although below the range of 1 to 4 pg of TEQ per kg of body weight per day set by the World Health Organization, emphasize the need for strict and continuous monitoring of fish oil contamination to reduce, as much as possible, the risks to human health.     

Estimation of the dietary intake of pesticide residues, lead, cadmium, arsenic and radionuclides in France

Estimation of the dietary exposure of French consumers to 10 pesticides (omethoate, oxydemeton, phosalon, phosphamidon, triazophos, dicofol (op'+pp'), parathion ethyl, dichlorvos, procymidon and vinchlozolin), three heavy metals (lead, cadmium and arsenic) and three radionuclides (¹³⁴caesium, ¹³⁷caesium and ¹³¹iodine) from collected duplicate portion in mass catering establishments in 1998/1999 are reported, and compared with those from previous French studies as well as those from other countries. Dietary exposure estimates appear to be reassuring, in that Estimated Daily Intake (EDI) estimates are generally low, representing at maximum only 4% of the Acceptable Daily Intake (ADI) for pesticide residues and 28% of the Provisional Tolerable Weekly Intake (PTWI) for heavy metals. Moreover, none of the three radionuclides has been found in duplicate meals. When comparisons are possible, estimated dietary exposures for heavy metals are lower than those from previous French studies and similar or above those from other countries.     

初榨橄榄油风味化合物研究进展

阐述了初榨橄榄油风味的主要来源途径即脂氧合酶途径,对影响初榨橄榄油风味特征的若干因素如品种和地理环境,油橄榄果实成熟度,加工工艺,储藏条件等因素进行了讨论和分析.介绍了初榨橄榄油中挥发性化合物的分析检测方法,并且展望了橄榄油风味化合物研究的应用和发展前景.     

Chronic dietary risk for pesticide residues in food in Brazil: an update.

The objective was to conduct a dietary risk assessment of pesticides registered in Brazil up to 14 January 2004. The theoretical maximum daily intake (TMDI) was calculated for 275 compounds using the Brazilian maximum residue limits (MRL) and food consumption. The chronic dietary risk assessment was conducted by comparing the TMDI with the Brazilian acceptable daily intake (ADI) or, when not available, with the ADI from other sources. The TMDI was higher than the ADI (%ADI>100) in at least one Brazilian region for eight pesticides, including five organophosphorus insecticides. For these compounds, the higher TMDI (expressed as %ADI) ranged from 140 (metam sodium) to 14,000 (methyl bromide). Rice, beans, citrus and tomato were the commodities that contributed most to ingestion. Change in pesticide use patterns and the establishment of ADIs by the Brazilian government have reduced the number of compounds for which the TMDI exceeded the ADI in the last 4 years. Risk assessment methodology based on TMDI calculation, however, is conservative as it assumes that the food supply is always treated with all the registered pesticides for that crop and that one always consumes food containing residues at the tolerance level. Furthermore, for six compounds with TMDI exceeding the ADI, a more realistic estimation of the pesticide daily intake was conducted using monitoring residue data from the Brazilian National Pesticide Residue Program. For these compounds, the higher refined intakes ranged from 2% (dimethoate) to 180% (fenitrothion) of the ADIs. The implementation of a national pesticide residue monitoring programme by the government was important to allow the refinement of the risk assessment. However, adequate daily food consumption data are still needed to assess better the public health risk to Brazilian consumers from food produced from crops treated with pesticides.     

Effect of crushing on olive paste and virgin olive oil minor components

The present study focuses on the influence of the olive crushing technique on the minor composition of olive pastes and their corresponding virgin olive oils since these compounds are strongly related to their quality and characteristics. Two different cultivars, Arbequina and Cornicabra—known for their different minor component composition—were processed at laboratory scale using hammer mills at various breakage forces and grid hole diameters, a blade cutter and a mortar. Crushing and kneading produce a profound change in the composition of the phenolic compounds in the olive paste and in the final oil. Hydroxytyrosol derivatives in virgin olive oil were most affected by the crushing conditions. The stronger the crushing conditions (i.e. hammer crushers using smaller grid holes and a higher rotation speed), the higher the phenolic content in both olive paste and oil in both varieties. Interestingly, the effect on volatile compounds of milder or stronger crushing conditions was opposite to that described for the phenolic compounds.     

Recovery and characterisation of DNA from virgin olive oil

European Food Research and Technology - The characterisation of the genetic identity of DNA recoverable from olive oil could facilitate the assessment of its place of origin and conformity to type...     

Lipolytic yeasts distribution in commercial extra virgin olive oil

The olive oil lipase-producing yeasts can lower the quality of the product through the hydrolysis of the triacylglycerols. In this research the olive oil total yeasts were divided into five chromogenic groups, for each group the amount of the lipase-producing yeasts was evaluated and the more active isolates were classed. The trials showed the prevalence of more than three chromogenic yeast groups in the commercial poly-varieties of extra virgin olive oil mixture, whereas in the mono-varieties one, no more than one chromogenic yeast group prevailed according to the olive variety. The ratio of the lipase-producing yeast varied from 33% in the smooth brown chromogenic group to 83% in the wrinkly bluish one. The physiological and genetic analyses of the more active lipase-producing yeast belonging to each chromogenic group allowed us to classify the wrinkly red 1892 strain and the wrinkly bluish 1890 strain as Candida parapsilosis, whereas the smooth white 1885 strain was classed as Candida wickerhamii. The ribosomal (26S) D1/D2 region sequencing results of the wrinkly white 1886 strain and the smooth brown 1887 strain are not identical to that of any known yeast species. They showed 8 substitution and 11 substitution plus 2 indels, respectively, different from Pichia mexicana and Pichia minuta. This is the first report where the human pathogen C. parapsilosis species was found in commercial extra virgin olive oil. The chromogenic group evaluation permitted the rapid preliminary identification of technological and human health important olive oil yeasts.     

Estimation of dietary intake of pesticide residues by the Italian population during 1997

In 1997 the Italian monitoring programme for pesticide residues in food comprised 7951 samples of 152 different foods for which a total of 275 pesticides were analysed. For 90 pesticides, the National Estimated Daily Intakes (NEDIs) were calculated by using the 90th percentile value and the food consumption data for the general Italian population. The calculated NEDIs were found to represent only a small portion of the respective Acceptable Daily Intake (ADI).     

Dietary intake of pesticide residues: cadmium, mercury, and lead.

Information on the dietary intake of chemical contaminants has been obtained from institutions participating in GEMS/Food. Contaminants studied include certain organochlorine and organophosphorous pesticides, PCBs, cadmium, mercury, and lead. The intakes are compared with toxicologically acceptable intake levels established by international expert groups. In most cases, dietary intakes of organochlorine and organophosphorous pesticides are well below the Acceptable Daily Intake (ADI) of the respective pesticide. Of some 21 countries providing information on the average dietary intake of cadmium, only in one case is the Provisional Tolerable Weekly Intake (PTWI) exceeded. Several countries identified cereals and cereal products and root and tuber vegetables as the main contributors to the dietary intake of cadmium. For mercury, all reported intakes are below the PTWI of methylmercury. The contribution of fish to the total intake of mercury varied from 20% to 85%, depending on the country. Therefore, the general assumption that fish is the main contributor to the total dietary intake of mercury may, at times, not be justified. Average dietary intake of lead exceeding or approaching the PTWI are reported for adults and infants and children in some countries. Foodstuffs which contribute most to the intake of lead vary from country to country, and have been identified as being alternately drinking water, beverages, cereals, vegetables and fruit.     

Detection of hazelnut oil in virgin olive oil by a spectrofluorimetric method

The possibilities of a spectrofluorimetric method joined to multivariate analysis to assess the genuineness of olive oil in admixtures with hazelnut oils were studied. Virgin olive, virgin hazelnut and refined hazelnut oil samples and admixtures between them at 5, 10, 15, 20, 25 and 30% adulteration were analysed at _ex=350 nm. The precision of the method, in terms of repeatability and internal reproducibility, was established by means of the analysis of a virgin olive oil sample under different conditions, the RSD showing values less than 10%. Raw data of the spectra were subjected to mathematical treatment by calculation of the first derivative, selection of the maximum values and application of one-way ANOVA, to assess the most prominent variables in the discrimination process. The response to the addition of adulterant was linear, adjusted-R²=0.99 for virgin olive and refined hazelnut oil mixtures, and 0.98 for virgin olive and virgin hazelnut oil mixtures. Stepwise linear discriminant analysis applied to each admixture separately and to the whole set of samples allowed 100% correct classifications.