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At least 307 records · Page 17Linked to original sources
PubMed2006

Reactive oxygen species in in vitro pesticide-induced neuronal cell (SH-SY5Y) cytotoxicity: role of NFkappaB and caspase-3.

Oxidative stress has been implicated in pesticide-induced neurotoxicity, based on its role in the cascade of biochemical changes that lead to dopaminergic neuronal cell death. We have, therefore, examined the role of oxidative stress caused by the pesticides endosulfan and zineb in human neuroblastoma cells (SH-SY5Y) in culture. Upon treatment with 50-200 microM concentrations of either of these pesticides, SH-SY5Y cells generated both superoxide anion and hydrogen peroxide in a dose-and time-dependent manner. Mixtures of the pesticides significantly enhanced the production of these reactive oxygen species compared to individual pesticide exposures. Pesticide treatment decreased superoxide dismutase, glutathione peroxidase, and catalase activities in SH-SY5Y cells. Additionally, these pesticides induced lipid peroxide (thiobarbituric acid reactive products) formation in these cells. While both pesticides individually (at 100 microM) increased caspase-3 activity, cells exposed to a mixture of the pesticides exhibited significantly low levels of this enzyme, probably due to excessive necrotic cell death. Furthermore, exposure to these pesticides increased nuclear NFkappaB activity. Taken together, these findings suggest that the cytotoxicity of endosulfan and zineb, both individually and in mixtures may, at least in part, be associated with the generation of reactive oxygen species with concomitant increased expression of NFkappaB.

Caspase 3↗
PubMed2006

Genotoxic evaluation of workers employed in pesticide production.

Pesticides are widely used throughout the world in agriculture to protect crops and in public health to control diseases. Nevertheless exposure to pesticides can represent a potential risk to humans. Pesticide manufacturing unit workers are prone to possible occupational pesticide exposure. Therefore, this study was performed to evaluate the genotoxic effect of pesticide exposure in these workers. In the present investigation 54 pesticide workers and an equal number of control subjects were assessed for genome damage in blood lymphocytes utilizing the chromosomal aberration analysis and the buccal epithelial cell by adopting the micronucleus test. The results suggested that pesticide workers had a significantly increased frequency of chromosomal aberrations when compared with controls (mean+/-S.D., 8.43+/-2.36 versus 3.32+/-1.26; P<0.05). Similarly, the pesticides exposed workers showed a significant increase in micronucleated cells compared with controls (1.24+/-0.72 versus 0.32+/-0.26; P<0.05). Analysis of variance revealed that occupational exposure to pesticides had a significant effect on frequency of micronuclei (P<0.05), whereas smoking, age, gender and alcohol consumption had no significant effect on genetic damage (P>0.05). However, no association was found between years of exposure, smoking, age, gender, alcohol consumption and higher levels of genetic damage as assessed by the chromosomal aberration assay (P>0.05). Our findings indicate that occupational exposure to pesticides could cause genome damage in somatic cells.

Adult↗
PubMed2005

Disposal of unwanted pesticides in Stellenbosch, South Africa.

BACKGROUND: Unwanted pesticides in developing countries are major environmental health threats. This study followed-up a previous audit of unwanted and obsolete pesticides on farms in a rural district of South Africa six years after a National Retrieval Project (NPR) was undertaken. METHODS: A descriptive survey of 37 farms that had been in possession of unwanted pesticides in a 1995 survey and a purposive sample of 34 neighbouring farms, was carried out. The survey data included farm details; details of unwanted pesticide stocks, volumes of empty containers and safety and hygiene of pesticide stores. In addition, management was asked if they had been informed about and participated in the 1997 NPR and similarly whether they were aware of the retrieval planned by the African Stockpiles Programme (ASP). RESULTS: Forty (56%) farms were in possession of obsolete pesticides of which 24 (59%) were farms that had unwanted stocks in the previous survey. There were more than 9 tonnes of these pesticides, 50% more than in the previous survey, including 20 chemicals banned, withdrawn or restricted in South Africa or classified as WHO Class I toxicity. Over 2,800 kg of pesticides (30%) were not identifiable. None of the farms participated in the NPR, although 47 knew of the initiative. Only six farmers (9%) knew of the ASP initiative. Fifty-nine farms (83%) had empty containers on the premises. Most pesticide stores (67%) had floors contaminated with chemicals. CONCLUSION: The survey found that despite the NPR, the problem of unwanted pesticides in the study area and probably throughout South Africa has deteriorated. National and international policies should control the problem at source and encourage more sustainable agriculture.

Agriculture↗
PubMed2006

Use and storage of domestic pesticides in the UK.

Several epidemiological studies, particularly from the United States, have suggested health concerns may arise from the chronic exposure of young children to pesticides in their home environment. Most of these studies are retrospective and the available pesticide exposure information is either subject to the problem of recall or derived from surrogate information. Currently, little is known about the extent of pesticide use in homes and gardens in the UK. This was investigated in this study using a sample of parents from the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort in and around Bristol. The level and extent of pesticide use by parents was explored through interviews that took place at the homes of the participants during August to November 2001, followed by an inventory of products stored in the home. From the results, 93% of parents had used at least one pesticide over the preceding year with the highest use being in the garden, second inside the home, followed by treating pets and head lice. Most households reported using one to five different products over the past year, with a mean of 3.5. The frequency of pesticide use showed that a minority of parents are using pesticides in the high frequency range. Over 85 different pesticide products were found to be stored in 76% of homes, with 76 different types of pesticide active ingredients. Insecticides were the most commonly used and stored pesticide.

Animals↗
PubMed2004

The combined antiandrogenic effects of five commonly used pesticides.

In this study, mixture effects of five dissimilarly acting pesticides were analyzed for antiandrogenic effects in vitro and in vivo. Deltamethrin, methiocarb, prochloraz, simazine, and tribenuron-methyl are all commonly used for agricultural and horticultural purposes. Concentration-response curves for the inhibition of R1881-induced transcriptional activity of the androgen receptor (AR) in vitro of each pesticide alone and in an equimolar mixture were obtained. The IC25 values for deltamethrin, methiocarb, prochloraz, and the mixture were 5.8, 5.8, 3.5, and 7.5 microM, respectively. Simazine and tribenuron-methyl were ineffective. Applying the isobole method resulted in an isobole coefficient of 0.94 at IC25 for the effect of the mixture, indicating additive effects of the compounds. Comparison of observed effects and effects calculated by assuming additivity also strongly indicated additive effects of the pesticides in vitro. In vivo, each of the five pesticides and a mixture of the pesticides were tested for antiandrogenic effects in castrated testosterone-treated Wistar rats. The mixture induced a significant change of weights of the levator ani/bulbocavernosus muscle and adrenal glands. Changes in gene expression in ventral prostates were observed as distinct effects on levels of ornithin decarboxylase (ODC) mRNA and effects on levels of prostate binding protein subunit C3 (PBP C3) mRNA. No pesticide-induced effect on the level of testosterone-repressed prostatic message 2 (TRPM-2) mRNA was observed, whereas flutamide increased TRPM-2 levels. In conclusion, the pesticides were found to act additively in vitro. In vivo, the organ weight changes indicated that the pesticides had an accumulating effect that was not observed for the individual pesticides. Several pesticide-induced gene expression changes were observed, indicating that these are either very sensitive antiandrogenic end-points or that these changes are induced by a pathway not related to AR.

Androgen Antagonists↗
PubMedDate not supplied

[Pesticide application practices in agricultural workers].

OBJECTIVE: We describe the sociodemographic characteristics and determinants of pesticide exposure in agricultural workers applying pesticides. METHODS: The workers selected were included in a case-control study carried out in the Autonomous Community of Valencia in Spain. Contact was made by telephone and individuals who had been involved in agricultural work during the relevant period of exposure were interviewed face-to-face to gain information on the following determinants of pesticide exposure: crops and periods worked, mixing of products, treatment equipment, participation in the washing of equipment, use of personal protection during the treatments and knowledge of the risks of pesticide exposure. RESULTS: Eighty-nine workers, aged between 16 and 46 years old, were included. Most of the interviewees had primary education or less. Pesticide treatments were mostly applied on high crops (82%), with manual equipment (61%) and throughout the year (45%). Workers frequently performed tasks involving additional exposure to pesticides (mixing chemicals, 66%, or washing equipment, 60%). Sixty-five percent of the workers used no personal protection or used it defectively. No differences were found in personal protection use according to age, family income or education. Most of the workers (90%) reported knowledge of the health risks of pesticide exposure and 21% of them rated the risk as null. CONCLUSIONS: Workers involved in pesticide application use personal protection measures very defectively. There is a clear need to develop specific prevention programs for these workers. The determinants of pesticide exposure in agricultural workers described in this study should be properly assessed in epidemiological studies of the health effects of pesticides on agricultural workers.

Adolescent↗
PubMedDate not supplied

Pesticide poisoning: a major health problem in Sri Lanka.

Acute pesticide poisoning is a major public health problem in Sri Lanka. In several agricultural districts, it precedes all other causes of death in government hospitals. Most of the acute poisoning cases are intentional (suicide) and occur among young adults, mainly males. Poisoning due to occupational exposure is also common, but less well documented. In an irrigation area in Sri Lanka a very high incidence of serious pesticide poisoning was observed, with 68% due to intentional ingestion of liquid pesticides. It is argued that the easy availability and widespread use of highly hazardous pesticides is the most important reason for this high number of poisoning cases. The frequent application of highly hazardous pesticides in high concentrations was often irrational and posed serious health and financial risks to the farmers. Sales promotion activities and credit facilities promoted this excessive pesticide use, which was not counteracted by an agricultural extension service. Hazardous practices when spraying pesticides were due to the impossibility of applying recommended protective measures under the local conditions, rather than to lack of knowledge. Current emphasis on programs that promote the safe use of pesticides through education and training of farmers will be ineffective in Sri Lanka because knowledge is already high and most poisoning cases are intentional. Instead, enforcement of legislation to restrict availability of the most hazardous pesticides would result in an immediate health benefit. Improved agricultural extension services to promote alternative non-chemical methods of pest control is the most important strategy, in the long term, to prevent acute pesticide poisoning.

Adult↗
PubMed2000

Effectiveness of interventions in reducing pesticide overexposure and poisonings.

OBJECTIVE: The objective of this paper was to review the effectiveness of interventions to reduce pesticide overexposure and poisonings in worker populations. METHODS: We used the Cochrane Collaboration search strategy to search the following databases for articles that tested the effectiveness of interventions in reducing human pesticide exposure or poisonings: MEDLINE, EMBASE, and Occupational Safety and Health (NIOSHTC). Interventions considered included comparisons of pesticide application methods, pesticide mixing methods, worker education, biological monitoring programs, personal protective equipment (PPE) use, pesticide substitutions, and legislation. The outcomes of interest included biological monitoring measures or personal exposure monitoring indicating a reduction of pesticide exposure, observed increased use of PPE, reduction in lost workdays, and where possible, evidence of changes in pesticide poisoning rates as identified by registries and population surveys. Studies were reviewed in depth with special attention to size and study design. RESULTS: Most studies evaluated exposure during differing configurations of PPE or during different mixing or handling methods. Most studies were small field tests of protective equipment involving less than 20 workers. Some studies examined biological indices of exposure such as cholinesterase or urinary metabolites. Studies showed that PPE was effective in reducing exposure. No controlled studies were found that addressed reducing pesticide poisonings. CONCLUSIONS: Changes in application procedures, packaging, mixing, use of personal protective equipment, and biological monitoring reduced pesticide exposure under controlled conditions. Cholinesterase monitoring can identify workers with a higher risk of overexposure. Most techniques were not tested in actual worksite programs. Interventions should be examined for their ability to reduce pesticide overexposure in actual working populations. No controlled evaluations of large legislative initiatives were found.

Environmental Monitoring↗
PubMed2003

Genotoxicity of pesticides: a review of human biomonitoring studies.

Pesticides constitute a heterogeneous category of chemicals specifically designed for the control of pests, weeds or plant diseases. Pesticides have been considered potential chemical mutagens: experimental data revealed that various agrochemical ingredients possess mutagenic properties inducing mutations, chromosomal alterations or DNA damage. Biological monitoring provides a useful tool to estimate the genetic risk deriving from an integrated exposure to a complex mixture of chemicals. Studies available in scientific literature have essentially focused on cytogenetic end-points to evaluate the potential genotoxicity of pesticides in occupationally exposed populations, including pesticide manufacturing workers, pesticide applicators, floriculturists and farm workers. A positive association between occupational exposure to complex pesticide mixtures and the presence of chromosomal aberrations (CA), sister-chromatid exchanges (SCE) and micronuclei (MN) has been detected in the majority of the studies, although a number of these failed to detect cytogenetic damage. Conflicting results from cytogenetic studies reflect the heterogeneity of the groups studied with regard to chemicals used and exposure conditions. Genetic damage associated with pesticides occurs in human populations subject to high exposure levels due to intensive use, misuse or failure of control measures. The majority of studies on cytogenetic biomarkers in pesticide-exposed workers have indicated some dose-dependent effects, with increasing duration or intensity of exposure. Chromosomal damage induced by pesticides appears to have been transient in acute or discontinuous exposure, but cumulative in continuous exposure to complex agrochemical mixtures. Data available at present on the effect of genetic polymorphism on susceptibility to pesticides does not allow any conclusion.

Chromosome Aberrations↗
PubMed2006

Atmospheric deposition of current-use and historic-use pesticides in snow at national parks in the western United States.

The United States (U.S.) National Park Service has initiated research on the atmospheric deposition and fate of semi-volatile organic compounds in its alpine, sub-Arctic, and Arctic ecosystems in the Western U.S. Results for the analysis of pesticides in seasonal snowpack samples collected in spring 2003 from seven national parks are presented herein. From a target analyte list of 47 pesticides and degradation products, the most frequently detected current-use pesticides were dacthal, chlorpyrifos, endosulfan, and gamma-hexachlorocyclohexane, whereas the mostfrequently detected historic-use pesticides were dieldrin, alpha-hexachlorocyclohexane, chlordane, and hexachlorobenzene. Correlation analysis with latitude, temperature, elevation, particulate matter, and two indicators of regional pesticide use reveal that regional current and historic agricultural practices are largely responsible for the distribution of pesticides in the national parks in this study. Pesticide deposition in the Alaskan parks is attributed to long-range transport because there are no significant regional pesticide sources. The percentage of total pesticide concentration due to regional transport (%RT) was calculated for the other parks. %RT was highest at parks with higher regional cropland intensity and for pesticides with lower vapor pressures and shorter half-lives in air.

Agriculture↗
PubMed2003

Comparative persistence of pesticides on selected cultivars of specialty vegetables.

The behavior and dissipation of several pesticides on selected cultivars of specialty vegetable crops were compared to determine appropriate preharvest intervals for compliance with maximum residue limits. To reduce application variability, a tank mix of pesticides was applied for each trial. Residues of eight pesticides applied to bok choi, Chinese broccoli, and fuzzy squash were similar for the two leafy vegetables; residues were higher than on squash because of the latter's larger mass-to-surface area ratio. Whereas residues of five of the nine pesticides applied to cabbage, Chinese cabbage, and bok choi did not differ significantly from 3 to 14 days after application, residues of cypermethrin and three fungicides were significantly higher on Chinese cabbage and bok choi. The residue deposits of the pesticides were about 50% lower on Chinese cabbage and 90% lower on cabbage than on bok choi. Dissipation of residues on different cultivars of lettuce and cabbage were compared after application of nine pesticides. With the exception of captan, residues on head lettuce were lower than on the other lettuces on day 1; cultivar differences were not significant for most of the nine applied pesticides on days 3 and 8. Generally, residues of the nine individual pesticides on storage cabbage, savoy cabbage, Chinese cabbage, and tah tsai did not differ significantly from day 1 to day 7 after application. Residue concentrations were generally significantly higher on bok choi than on the other cultivars. Residue deposits generally correlated with the rate of application; residues of captan, however, were about 50% of the predicted value. Significant differences in deposit and dissipation were observed among cultivars and pesticides, with dramatic initial decreases for diazinon and parathion. Because of their higher exposed surface area-to-mass ratios, leafier crops had higher residue concentrations than head varieties. Residues on lettuce cultivars were higher than on the cabbages. The results clearly indicate that structure significantly affects residue deposit and dissipation, and pesticide recommendations cannot always be extended to specialty crops without an investigation of the changes in preharvest intervals to prevent violations of the maximum residue limits.

Brassica↗
PubMed2006

Multiresidue method for determination of 35 pesticides in virgin olive oil by using liquid-liquid extraction techniques coupled with solid-phase extraction clean up and gas chromatography with nitrogen phosphorus detection and electron capture detection.

A method for the multiresidue determination of 35 pesticides (30 insecticides and five herbicides) in olive oil by gas chromatography (GC) is described. Three liquid-liquid extraction (LLE) procedures based on (i) partition of pesticides between acetonitrile (ACN) and oil solution in n-hexane, (ii) partition of pesticides between saturated ACN with n-hexane and oil solution in n-hexane saturated with ACN, and (iii) partition of pesticides between ACN and oil were tested for the optimization of the highest pesticide recoveries with the lowest oil residue in the final extracts. Experimental tests were preformed in order to study the efficiency of different clean up procedures with N-Alumina, Florisil, C18, and ENVI-Carb solid-phase extraction (SPE) cartridges for the compounds analyzed by GC-nitrogen phosphorus detection. A second step of clean up was also performed for the compounds analyzed by GC-electron capture detection (ECD), by using phenyl-bonded silica (Ph), diol-bonded silica (Diol), cyanopropyl-bonded silica (CN), and amino propyl-bonded silica (NH2) SPE cartridges. LLE of the oil solution in hexane with ACN followed by an ENVI-Carb SPE clean up of the extract gave the best results for all target compounds. The ACN extract was additionally cleaned through a Diol-SPE cartridge for the determination of pesticides analyzed mainly by GC-ECD. Pesticide recoveries form virgin olive oil spiked with 20, 100, and 500 microg/kg concentrations of pesticides ranged from 70.9 to 107.4%. The proposed method featured good sensitivity, pesticide quantification limits were low enough, and the precision, expressed as relative standard deviation, ranged from 2.4 to 12.0%. The proposed method was applied successfully for the residue determination of the selected pesticides in commercial olive oil samples.

Chromatography, Gas↗
PubMed2006

Lysimeter experiment to investigate the potential influence of diffusion-limited sorption on pesticide availability for leaching.

Pesticide leaching from soil has been shown to decrease with increasing time from application to irrigation. It is hypothesized that the availability of compounds for leaching decreases due to diffusion and sorption inside soil aggregates. Previous work showed that pesticide sorption inside soil aggregates increases significantly during the first days after application. The study presented here tested if diffusion into aggregates could explain the leaching of four aged pesticides from manually irrigated soil cores. Azoxystrobin, chlorotoluron, cyanazine, and bentazone were applied to 30 undisturbed cores (25 cm long, 23.7 cm diameter) from a clay loam soil. The soil cores were irrigated 1, 3, 7, 14, and 28 days after application. Leachate was collected and analyzed. The amount of pesticide found in leachate decreased rapidly with time from application. Pesticide losses in leachate declined 2.5-27 times faster than total residues in soil. The decline was 4-5 times faster for the more strongly sorbed pesticides (azoxystrobin, chlorotoluron, and cyanazine) than for bentazone. In previous work, we derived a model to describe sorption and diffusion of the pesticides in small aggregates from the same soil. The diffusion model was used here to describe sorption inside the large aggregates in the soil cores and extended to describe pesticide leaching by interaggregate flow. The model showed a significant decline in leaching with time from application, which supports the theory that diffusion-limited sorption in aggregates influences the availability for pesticide leaching, although it does not exclude alternative explanations for this decline. The model well described the decline in leaching for three out of four pesticides. The interaggregate transport model could, however, not account for the amount of preferential flow in the cores and underestimated the leaching of bentazone.

Benzothiadiazines↗
PubMedDate not supplied

Using GIS and historical records to reconstruct residential exposure to large-scale pesticide application.

Investigation of pesticide impacts on human health depends on good measures of exposure. Historical exposure data are needed to study health outcomes, such as cancer, that involve long latency periods, and other outcomes that are a function of the timing of exposure. Environmental or biological samples collected at the time of epidemiologic study may not represent historical exposure levels. To study the relationship between residential exposure to pesticides and breast cancer on Cape Cod, Massachusetts, historical records of pesticide use were integrated into a geographic information system (GIS) to estimate exposures from large-scale pesticide applications between 1948 and 1995. Information on pesticide use for gypsy moth and other tree/vegetative pest control, cranberry bog cultivation, other agriculture, mosquito control, recreational turf management, and rights-of-way maintenance is included in the database. Residents living within or near pesticide use areas may be exposed through inhalation due to drift and volatilization and through dermal contact and ingestion at the time of application or in later years from pesticides that deposit on soil, accumulate in crops, or migrate to groundwater. Procedures were developed to use the GIS to estimate the relative intensity of past exposures at each study subject's Cape Cod addresses over the past 40 years, taking into account local meteorological data, distance and direction from a residence to a pesticide use source area, size of the source area, application by ground-based or aerial methods, and persistent or nonpersistent character of the pesticide applied. The resulting individual-level estimates of relative exposure intensity can be used in conjunction with interview data to obtain more complete exposure assessment in an epidemiologic study. While the database can improve environmental epidemiological studies involving pesticides, it simultaneously illustrates important data gaps that cannot be filled. Studies such as this one have the potential to identify preventable causes of disease and guide public policies.

Agrochemicals↗
PubMed2003

Transfer efficiencies of pesticides from household flooring surfaces to foods.

The transfer of pesticides from household surfaces to foods was measured to determine the degree of excess dietary exposure that occurs when children's foods contact contaminated surfaces prior to being eaten. Three household flooring surfaces (ceramic tile, hardwood, and carpet) were contaminated with an aqueous emulsion of commercially available pesticides (diazinon, heptachlor, malathion, chlorpyrifos, isofenphos, and cis- and trans-permethrin) frequently found in residential environments. A surface wipe method, as typically used in residential exposure studies, was used to measure the pesticides available on the surfaces as a basis for calculating transfer efficiency to the foods. Three foods (apple, bologna, and cheese) routinely handled by children before eating were placed on the contaminated surfaces and transfers of pesticides were measured after 10 min contact. Other contact durations (1 and 60 min) and applying additional contact force (1500 g) to the foods were evaluated for their impact on transferred pesticides. More pesticides transferred to the foods from the hard surfaces, that is, ceramic tile and hardwood flooring, than from carpet. Mean transfer efficiencies for all pesticides to the three foods ranged from 24% to 40% from ceramic tile and 15% to 29% from hardwood, as compared to mostly non-detectable transfers from carpet. Contact duration and applied force notably increased pesticide transfer. The mean transfer efficiency for the seven pesticides increased from around 1% at 1 min to 55- 83% when contact duration was increased to 60 min for the three foods contacting hardwood flooring. Mean transfer efficiency for 10-min contact increased from 15% to 70% when a 1500 g force was applied to bologna placed on hardwood flooring. Contamination of food occurs from contact with pesticide-laden surfaces, thus increasing the potential for excess dietary exposure of children.

Air Pollution, Indoor↗
PubMed2003

Assessment of data quality for the NHEXAS--Part II: Minnesota children's pesticide exposure study (MNCPES).

The Minnesota Children's Pesticide Exposure Study (MNCPES) of the National Human Exposure Assessment Survey (NHEXAS) was conducted in Minnesota to evaluate children's pesticide exposure. This study complements and extends the populations and chemicals included in the NHEXAS Region V study. One of the goals of the study was to test protocols for acquiring exposure measurements and developing databases for use in exposure models and assessments. Analysis of the data quality is one element in assessing the performance of the collection and analysis protocols used in this study. Data quality information must also be available to investigators to guide analysis of the study data. During the planning phase of MNCPES, quality assurance (QA) goals were established for precision, accuracy, and quantification limits. The data quality was assessed against these goals. The assessment is complex. First, data are not available for all analytes and media sampled. In addition, several laboratories were responsible for the analysis of the collected samples. Each laboratory provided data according to their standard operating procedures (SOPs) and protocols. Detection limits were authenticated for each analyte in each sample type. The approach used to calculate detection limits varied across the different analytical methods. The analytical methods for pesticides in air, food, hand rinses, dust wipe and urine were sufficiently sensitive and met the QA goals, with very few exceptions. This was also true for polynuclear aromatic hydrocarbons (PAHs) in air and food. The analytical methods for drinking water and beverages had very low detection limits; however, there were very little measurable data for these samples. The collection and analysis methods for pesticides in surface press samples and soil, and for PAHs in dust wipes were not sufficiently sensitive. Accuracy was assessed primarily as recovery from field controls. The results were good for pesticides and PAHs in air (75-125% recovery). Recovery was lower (<75%) for pesticides in drinking water and beverages. The recovery of pesticides from hand rinses met QA goals (75-100%), but surface press samples showed lower recovery (50-70%). Analysis by gas chromatography-mass spectrometry (GC-MS) did not confirm the presence of atrazine and other pesticides in hand rinse and surface press samples that had been detected by GC-ECD, but instead GC-MS confirmed background interferences. Assessment of the precision of sample collection and analysis is based on the percent relative standard deviation (%RSD) between the results for duplicate samples. Data are available only for pesticides and PAHs in air. Precision was good (<20% RSD) for analytes with measurable data. There were a few analytes with %RSD >20%, but the number of data pairs was very small in these cases. Precision for instrumental analysis of food sample extracts was excellent, with the median %RSD < 20 for all measurable pesticides. The median %RSD for the analysis of replicate aliquots of food from the same sample composite was considerably higher, indicating the potential for inhomogeneity of food homogenates.

Child↗
PubMed2004

Qat chewing and pesticides: a study of adverse health effects in people of the mountainous areas of Yemen.

Chewing qat leaves, Cathula Edulis, is now a very common behaviour among the people of the mountainous areas of Yemen. For about the past 20 years, in tandem with national development, qat chewing has been rapidly expanding, and the use of chemical pesticides in qat production has been increasing. In this study, the adverse effects on human health of qat chewing combined with pesticide use were investigated. Results of interviews and questionnaires showed that chewers of qat grown with few or no chemical pesticides and chewers of qat grown with chemical pesticides have considerably different subjective symptoms. Chewers of qat produced in fields where chemical pesticides are used regularly have more symptoms than chewers of qat produced in fields where chemical pesticides are rarely or never used. Chewers of qat produced with more chemical pesticides, in particular, experience acute adverse effects on the digestive system and chronic adverse effects such as body weakness and nasal problems. Farmers who chew homemade qat on which they spread chemical pesticides by themselves may have the highest health risks regarding the combination of qat and pesticides. It is concluded that chewing qat grown with chemical pesticides causes considerable adverse health effects in human beings.

Administration, Oral↗
PubMed2005

Risk factors to pesticide exposure and associated health symptoms among cut-flower farmers.

The study looked into the risk factors associated with pesticide exposure among cut-flower farmers. A survey questionnaire was given to 102 respondents in Barangay Bahong in La Trinidad, the center of cut-flower production in the Philippines. Results showed that 32% were symptomatic or had experienced pesticide-related illnesses since their first use of pesticides. The majority of the pesticides used by the farmers were Categories Ib and II which are moderately or highly hazardous chemicals. Individuals with signs and symptoms most often centered on the eye, ear, nose and throat (EENT) (44 respondents reporting these symptoms) followed by general and neuralgic (16 respondents) and the integumentary (14 respondents). The most common general signs and symptoms manifested were weakness followed by fatigue and muscle pain then by chills and fever. The most common EENT manifestations were eye itchiness and blurring of vision. For neurological signs and symptoms, dizziness followed by headache was reported. Logistic regression showed that illnesses for the past 12 months were associated with certain risk factors such as farm use of pesticides, exposure to pesticide while applying it, respiratory inhalation of pesticide vapours and mists (p = 0.05). Moreover, those who re-entered a recently sprayed area were 20 times more likely to get ill during the past 12 months than those who did not. Those who used pesticide-contaminated pieces of fabric to wipe sweat off their faces were 2% more likely to get ill, and those who had spills on their bodies while applying pesticide were 26 times more likely to get ill. The study suggested that the risk factors to pesticide exposure should be considered in policy formulations for the cut-flower farmers in the country.

Adolescent↗