Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PESTICIDES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,441 records · Page 80Linked to original sources
PubMed1977

Nitrosation in vitro and in vivo by sodium nitrite, and mutagenicity of nitrogenous pesticides.

37 nitrogenous pesticides, belonging to the chemical groups of amides, carbamates and ureas, were nitrosated with sodium nitrite in vitro. The nitrosated compounds were tested for mutagenic activity in the bacterial spot test with Salmonella typhimurium his G 46. Those pesticides reacting positively in this test after nitrosation were then fed to mice in combination with sodium nitrite in order to assess the formation and mutagenicity of these nitroso compounds in vivo. With the already known exception of ethylenethiourea (ETU), no pesticide produced enhanced numbers of micronuclei in mouse bone-marrow erythrocytes when fed together with nitrite. Dose-response experiments with intraperitoneal injection of N-nitroso-ETU revealed an apparent no-effect level of about 15--18 mg/kg. The findings are correlated with the pesticide residues actually present in the environment.

Animals↗
PubMed2004

Repeated dose 28-day oral toxicity study in Wistar rats with a mixture of five pesticides often found as residues in food: alphacypermethrin, bromopropylate, carbendazim, chlorpyrifos and mancozeb.

Six dose groups of 8 male and female rats respectively received a daily dose equivalent to 0, 0.15, 0.006, 0.03, 0.15 or 0.3 mg/kg b.w./day chlorpyrifos (groups 1-6) and the last four dose groups (groups 3-6) received in addition daily doses equivalent to 18 mg/kg b.w./day alphacypermethrin, 30 mg/kg b.w./day bromopropylate, 45 mg/kg b.w./day carbendazim and 12.5 mg/kg b.w./day mancozeb for 28 days. Plasma acetylcholinesterase was significantly decreased in the groups 2, 5 and 6 males. Total white blood cell count was significantly lower in females of group 6. Total red blood cell count, haematocrite and haemoglobin concentration was significantly reduced in both male and female rats of groups 5 and 6. Relative liver weight was significantly increased in groups 3-6 male and female rats. Absolute thyroid gland weight was significantly increased in groups 3, 5 and 6 male rats and of groups 3-6 female rats, and relative thyroid gland weight was significantly increased in groups 2-6 male rats and of groups 3-6 female rats. Absolute thymus weight of groups 3-6 male and female rats and relative thymus weight of groups 3-6 male rats and groups 3 and 4 female rats was significantly decreased. A mild degree of centrilobular cell hypertrophy of the liver was seen in all male rats and of three female rats of group 6. In the thyroid gland follicular cell hypertrophy was present in one female in the control group and in six females and seven males of group 6. It was concluded that inhibition of acetylcholinesterase activity in plasma and brain by chlorpyrifos was not enhanced by co-administration of the other four pesticides. Effects were seen in liver, thyroid, thymus and blood in the combination groups. However, identification of the pesticide(s) responsible for these changes would require further studies of the individually pesticides as well as various combinations of the pesticides.

Acetylcholinesterase↗
PubMed2005

Guidance on setting of acute reference dose (ARfD) for pesticides.

This paper summarises and extends the work developed over the last decade by the Joint FAO/WHO Meeting on Pesticide Residues (JMPR) for acute health risk assessment of agricultural pesticides. The general considerations in setting of acute reference doses (ARfDs) in a step-wise process, as well as specific considerations and guidance regarding selected toxicological endpoints are described in detail. The endpoints selected are based on the practical experience with agricultural pesticides by the JMPR and are not a comprehensive listing of all possible relevant endpoints. Haematotoxicity, immunotoxicity, neurotoxicity, liver and kidney toxicity, endocrine effects as well as developmental effects are taken into account as acute toxic alerts, relevant for the consideration of ARfDs for pesticides. The general biological background and the data available through standard toxicological testing for regulatory purposes, interpretation of the data, conclusions and recommendations for future improvements are described for each relevant endpoint. The paper also considers a single dose study protocol. This type of study is not intended to be included in routine toxicological testing for regulatory purposes, but rather to guide further testing when the current database indicates the necessity for an ARfD but does not allow a reliable derivation of the value.

Animals↗
PubMed2006

GerES IV pilot study: assessment of the exposure of German children to organophosphorus and pyrethroid pesticides.

Organophosphorus pesticides and pyrethroids are widely used in German agriculture and residential settings. Their occurrence in human biological samples can be used as an indicator for the exposure of children to these compounds. Using multivariate evaluation the routes of exposure can be identified. In the pilot study of GerES IV, metabolites of pyrethroids and organophosporus pesticides were analysed in urine of children aged 2-17 years (n = 396 and 363). The 95th percentiles for the metabolites of the pyrethroids in urine were: cis-DCCA 0.74 microg/l, trans-DCCA 1.7 microg/l, DBCA 0.52 microg/l, F-PBA < 0.1 microg/l, and 3-PBA 2.4 microg/l. 3-PBA was detected in 90% of the samples. The 95th percentiles for the organophosphorus metabolites in urine were: DMP 118 microg/l, DEP 20 microg/l, DMTP 124 microg/l, DETP 11 microg/l, DMDTP 11 microg/l, DEDTP < 1.0microg/l. DMTP was the metabolite most frequently detected in the samples (90%). Based on the metabolites analysed in urine the exposure to organophosphorus pesticides is mainly influenced by age, consumption of fresh fruits and fruit juice, living in an urban area, and season. A rough estimation revealed that the ADI values for organophosphorus pesticides might be exceeded. However, these results require further exploration. The exposure to pyrethroids is influenced by age, sampling location, consumption of boiled vegetables, and the use of biocides indoors at home. In addition, a significant correlation between permethrin in house dust and the metabolite concentrations in urine could be observed. Thus it seems likely that ingestion of house dust contributes to children's exposure.

Adolescent↗
PubMed2002

Fate of (14)C-labeled soybean and corn pesticides in tropical soils of Brazil under laboratory conditions.

The dissipation rate of seven currently used soybean and corn pesticides in two tropical soils (Ustox and Psamments) of Brazil was studied in a laboratory incubation experiment. Dissipation half-lives of pesticides ranged between 2 (monocrotofos) and 90 days (endosulfan-beta). The contrasting clay contents of the studied tropical soils (130 versus 470 g of clay kg(-1) of soil) did not influence the dissipation dynamics of pesticides substantially. Mineralization to CO(2) was high [up to 78% of the applied radioactivity (AR)] for the studied organophosphorus compounds and deltamethrin, which also formed considerable amounts of bound residues (>20% of AR) during the 80 days of incubation. The highest portion of nonextractable residues was found for alachlor and simazine (55-60% of AR). In contrast, the nonpolar trifluralin and endosulfan formed only small amounts of bound residues (mostly <20% of AR) but showed the highest dissipation half-lives (>14 days) in the studied soils, also due to a low mineralization rate. When endosulfan-sulfate, as the main metabolite of endosulfan, was considered, the half-life time of endosulfan compounds (sum of -alpha, -beta, and -sulfate) was enhanced to >160 days in both soils. In comparison with the laboratory experiments, dissipation half-life times of chlorpyrifos, endosulfan-alpha, and trifluralin were shortened by a factor of 10-30 in field trials with the same soils, which was related to the volatilization potential of pesticides from soils.

Acetamides↗
PubMed2007

Solid-phase extraction combined with high-performance liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry analysis of pesticides in water: method performance and application in a reconnaissance survey of residues in drinking water in Greater Cairo, Egypt.

Monitoring of water resources for pesticide residues is often needed to ensure that pesticide use does not adversely impact the quality of public water supplies or the environment. In many rural areas and throughout much of the developing world, monitoring is often constrained by lack of testing facilities; thus, collection of samples and shipment to centralized laboratories for analysis is required. The portability, ease of use, and potential to enhance analyte stability make solid-phase extraction (SPE) an attractive technique for handling water samples prior to their shipment. We describe performance of an SPE method targeting a structurally diverse mixture of 25 current-use pesticides and two common degradates in samples of raw and filtered drinking water collected in Greater Cairo, Egypt. SPE was completed in a field laboratory in Egypt, and cartridges were shipped to the United States for elution and high-performance liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry analysis. Quantitative and reproducible recovery of 23 of 27 compounds (average = 96%; percent relative standard deviation = 21%) from matrix spikes (1 microg L-1 per component) prepared in the field and from deionized water fortified similarly in the analytical laboratory was obtained. Concurrent analysis of unspiked samples identified four parent compounds and one degradate in drinking water samples. No significant differences were observed between raw and filtered samples. Residue levels in all cases were below drinking water and "harm to aquatic-life" thresholds, indicating that human and ecological risks of pesticide contamination were relatively small; however, the study was limited in scale and scope. Further monitoring is needed to define spatial and temporal variation in residue concentrations. The study has demonstrated the feasibility of performing studies of this type using SPE to extract and preserve samples in the field. The approach should be broadly applicable in many settings.

Chromatography, High Pressure Liquid↗
PubMed1980

Perspectives of the chemical fate and toxicity of pesticides.

The wide-spread use of pesticides in modern agriculture has created a need to investigate the chemical transformation of pesticides in plants and animals. This paper reviews the chemical and biochemical fate of various pesticides and other xenobiotics. Photochemical mechanisms appear to be the most common pathways for the abiotic transformation of these chemicals. Biotic transformation includes a large group of biochemical reactions which may result in either deactivation (detoxication) or activation (toxication) of bioactive compounds. The need for quality control in the production of pesticides is also discussed.

Animals↗
PubMed1980

Analytical approaches for determining human exposure to pesticides.

The presence of pesticides, both persistent and biodegradable, in the environment is a problem which is both significant and potentially dangerous to humans. An index of biodegradability is presented which is based on the correlation between environmental stability and fat solubility. Halogenated pesticides are, therefore, both more fat soluble and more resistant to biodegradation, while methylated pesticides are more water soluble and, therefore, more biodegradable. Three methods for detecting low-levels of halogenated pesticides are presented: the Macro, the Micro "Florisil," and the Micro "Silica." A method is also presented to detect these chemicals in blood. Two methods for the detection of nonpersistent, organophosphorus and carbamate insecticides, Cholinesterase inhibition and urinary metabolites, are described. Finally, methods of monitoring human exposure through the detection of phenols, phenoxy acids, alkyl phosphates, and anilines are presented.

Adipose Tissue↗
PubMed1999

Current trends in immunoassay-based kits for pesticide analysis.

Detection of pesticides and their metabolites in food and environmental samples in real time is the goal of many industries. Immunoassay technology has several attributes that make it a useful tool for screening purposes (e.g., selectivity, sensitivity, portability, and rapid turnaround time). Approximately 90% of the developed immunoassays for the pesticide residue analysis use the ELISA technique. Commercial kits are tailored to target different analytes, thus eliminating in some cases the need for clean-up steps. The manageability of the immunoassay test kit, together with its accuracy and speed of analysis, allows the rapid determination in situ of many samples simultaneously. This article gives an overview on the applications of the immunokits for pesticide analysis in drinking water and foods, as well as examples of different immunoassay formats commonly used. Special attention is given to sample extraction and clean-up procedures. Application to the determination of common pesticides and their detection limit are summarized. Immunoassay kits offer many practical advantages, and the acceptance of these methods depends on several factors, including the demonstration of quality and validity compared with reference methods. Although the advantages of the technique and their applications to food industry quality control are scarcely referred to in the literature.

Enzyme-Linked Immunosorbent Assay↗
PubMed1985

Reconstituted halogenated hydrocarbon pesticide and pollutant mixtures found in human tissues: effects on the immature male Wistar rat after short-term exposure.

Halogenated hydrocarbon insecticides and polychlorinated biphenyl (PCB) mixtures are routinely detected as residues in human adipose tissue, serum, and milk. Based on average values observed in analytical studies, reconstituted halogenated hydrocarbon pesticide mixtures and PCB mixtures were prepared and administered to immature male Wistar rats. The mixtures were administered at dose levels which approximate the concentrations which would be absorbed by an infant suckling for 180 days (low dose, L), and at three higher dose levels (2 X L, 10 X L, and 100 X L). The pesticide mixture contained isomeric hexachlorocyclohexanes, dieldrin, heptachlor epoxide, oxychlordane, trans-nonachlor, hexachlorobenzene, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane, and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene; the reconstituted PCB mixture contained 13 of the major congeners which have been identified in human milk samples. Administration of the L dose level of the pesticide (0.95 mg/kg), PCB (0.45 mg/kg), and pesticide plus PCB mixture (0.95 + 0.45 mg/kg, respectively) in corn oil on days 1 and 3 did not significantly alter hepatic drug-metabolizing enzyme activities or elicit any observable pathological damage 6 days after the first exposure. In contrast, administration of the higher dose levels of this mixture elicited a dose-dependent induction of several hepatic drug-metabolizing enzymes. Moreover, despite the short duration of exposure to these chemicals, the rats treated with the higher doses (10 X L and 100 X L) of these mixtures exhibited mild alterations in thyroid architecture, changes in hepatocellular nuclei including variations in chromatin distribution, vesiculation of larger nuclei, and frequent appearance of pyknotic shrunken nuclei.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2006

Possible mechanism of pesticide toxicity-related oxidative stress leading to airway narrowing.

The study was conducted to assess the magnitude of oxidative stress and lung function abnormalities in 34 male pesticide sprayers on exposure to pesticides in mango plantations. Biochemical studies on blood antioxidant enzymes revealed an unchanged glutathione level and increased level of malondialdehyde (P < 0.001), which indicates that pesticide sprayers may have suffered from oxidative stress. Decreased acetyl-cholinesterase levels (P < 0.001) in sprayers compared to the controls suggest inhibition of cholinesterase activity. The present study shows that pesticide toxicity might lead to oxidative stress and airway narrowing resulting in decreased peak expiratory flow rate.

Adolescent↗
PubMed2001

Effect of pesticides on Colpoclypeus florus (Hymenoptera: Eulophidae) and Trichogramma platneri (Hymenoptera: Trichogrammatidae), parasitoids of leafrollers in Washington.

Pesticides were evaluated for their effect on two parasitoid species, Colpoclypeus flouts and Trichogramma platneri, that are potential biological control agents of leafrollers in apple orchards. Organophosphate and carbamate insecticides were highly toxic to both parasitoids in topical applications, but foliar residues of some products were nontoxic after 7 d. At reduced rates, topically applied pyrethroids were low in toxicity to C. florus were highly toxic to T. platneri, and foliar residues were nontoxic after about 7 d. Imidacloprid and abamectin were highly toxic when applied topically to both parasitoids but were not toxic as 1-d-old residues. Insect growth regulators did not cause mortality either as topical applications or residues; however, diflubenzuron caused severe sublethal effects, completely blocking the production of C. florus offspring. Biorational pesticides, such as soap, oil, and B. thuringiensis products, caused no toxicity to C. florus but had a direct impact on T. platneri as topical applications through physical immobilization. The potential to integrate different pesticides with biological control of leafrollers and the need for a step-wise approach to evaluate the impact of pesticides against natural enemies is discussed.

Animals↗
PubMed1985

Pesticides.

The last 30 years have been marked by concern regarding the effects of pesticides on human health and on the environment. Unwanted and adverse effects on man and other nontarget organisms have been reported from many countries. The health effects recorded for thousands of people yearly are mainly caused by the inappropriate handling of pesticides or by accidents. The important task is to identify and evaluate the specific hazards of the handling and application of pesticides and the need to collaborate with the World Health Organization (WHO) and other organizations on promoting the health protection of exposed workers. The selectivity of chemical control methods can often be markedly improved by the proper choice of formulation and application techniques and, of course, by an appropriate choice and use of the pesticide itself. This work is an integral part of the international program on chemical safety based on and incorporating current WHO activities. The situation in the developing countries creates a new dimension for the work to be done. In these countries the working populations are affected by the general diseases prevailing in the community, as well as by many uncontrolled hazardous agents at work.

Food Contamination↗
PubMed2001

Trends of pesticide use in The Netherlands.

In 1991, a policy plan was adopted in the Netherlands, one of whose aims was a 50% reduction in pesticide use by 2000. The present paper surveys pesticide sales since 1974 and the use of such compounds in different crops per hectare as well as for the country as a whole. The results show that by the mid-1990s, pesticide consumption in kilogram terms had been reduced by about 50% compared to the mid-1980s. This reduction, however, was almost totally caused by the reduction in the use of soil disinfectants, while reduction targets for herbicides and fungicides were not met at all. Arable crops, especially potatoes and maize, which cover large areas in the Netherlands, contributed most to total consumption, while apples, tulips and lilies also made considerable contributions. On a per hectare per year basis, pesticide consumption was highest in ornamental plants like roses, chrysanthemums, lilies and hyacinths, followed by vegetables grown in greenhouses, apples and pears and mushroom cultivation. A remarkable feature is that the majority of the 20 most commonly used compounds (in terms of total consumption in kilograms of active ingredient or area sprayed) had already been introduced before 1980. On a kilogram basis, fungicides and soil disinfectants were used in the largest quantities, together with mineral oil and followed by herbicides. On a per hectare basis, herbicides played a more important role, while one insecticide also featured.

Agriculture↗
PubMed2001

POCER, a new pesticide risk indicator.

POCER, the pesticide occupational and environmental risk indicator, has been developed in order to be able to quantify the health and environmental risk from the use of pesticides in agriculture. The POCER indicator is used as a decision tool to rank and choose between alternative pesticides, to evaluate the effect of certain pesticide reduction measures and to evaluate the effectiveness of policy measures. The practical use of the indicator is explained using examples.

Agriculture↗
PubMed2001

Pesticide assessment of the banana sector in an Ecuadorian watershed.

A survey was conducted in several Ecuadorian banana plantations to determine the actual pesticide management and their environmental impacts. It was detected that glyphosate, propiconazole, imazalil, tridemorph and imazalil are the pesticides most used in the Ecuadorian banana sector. As a first step, two screening models (EQC and EXAMS) were used to determine the overall distribution of these pesticides in a unitary environment. Whereas EQC evaluates soil, water, sediment and air compartments, EXAMS only takes into account water and sediment compartments. Although both models show different results due to their different approaches, a comparison can still be done considering only the aquatic portion of the unitary environment. For the case study presented here, all 5 pesticides tend to affect more the soil and water compartment.

Agriculture↗
PubMedDate not supplied

Determination of organophosphorus and triazine pesticides in olive oil by on-line coupling reversed-phase liquid chromatography/gas chromatography with nitrogen-phosphorus detection and an automated through-oven transfer adsorption-desorption interface.

A method is described for the simultaneous determination of organophosphorus and triazine pesticides in olive oil, whereby reversed-phase liquid chromatography (LC) is coupled to gas chromatography by means of an automated through-oven transfer adsorption-desorption (TOTAD) interface. The olive oil needs to be filtered only before it is loaded into the liquid chromatograph, where preseparation of the pesticide residues from the other olive oil components is carried out by using methanol-water as the eluant. The LC fraction containing the pesticides is automatically transferred to the gas chromatograph by using the TOTAD interface, which almost totally eliminates the solvent, so that water-sensitive detectors such as the nitrogen-phosphorus detector can be used. Detection limits range from 0.07 to 0.38 microg/L for organophosphorus pesticides and from 6.0 to 7.0 microg/L for triazines. The results were compared with those obtained by flame ionization detection.

Adsorption↗
PubMed1991

Development of dermal and respiratory sampling procedures for human exposure to pesticides in indoor environments.

No standard methods presently exist for measuring air and surface residues in indoor environments following pesticide applications. Four studies of chlorpyrifos broadcast applications for flea control were conducted to test preliminary sampling guidelines developed by Health and Welfare Canada. Air and wipe samples were collected for 24 hr following 0.5% or 0.48% chlopryifos applications. Ventilation from open doors or windows reduced air concentrations substantially. Air concentrations also varied with sampler height; i.e., greater near the floor than at one m above the floor. Wipe sampling from aluminum foil exhibited high precision (less than 10% coefficient of variation), and wipe sampling of carpets and other surfaces did not show variability in excess of the variability in initial pesticide deposits produced by the application procedures. Residues recovered from treated surfaces decreased by 60-70% over 24 hr, while residues on untreated surfaces increased 200-300% over this period. The Guidelines for Assessment of Indoor Occupant Exposure to Pesticides developed by Health and Welfare Canada have been revised in light of these findings, and provide a set of standard procedures for monitoring indoor air and surface residues. Further studies will be required to determine human exposures and health risks resulting from indoor pesticide applications.

Air Pollutants↗