Pesticides In Plasma Research Articles

ALTERACIONES DEL CICLO MENSTRUAL DE ADOLESCENTES EXPUESTAS NO OCUPACIONALMENTE A UNA MEZCLA DE PLAGUICIDAS DE UNA ZONA AGRÍCOLA DE SAN LUIS POTOSÍ, MÉXICO. ESTUDIO PILOTO

Persistent organic pollutants are a group of chemical compounds of global concern due to the health damages caused by the exposure to them. Their capacity as endocrine disrupters is one of their main characteristics, being women in reproductive age the most vulnerable population. The aim of the present study was to evaluate the effect of exposure to a mixture of pesticides in the menstrual cycle of a sample of 29 teenagers between the ages of 12 and 17 years old from El Refugio, San Luis Potosi, Mexico, a community whose predominant activity is agriculture. The participants were trained to record in a diary/logbook all the events related to their menstrual cycle. Serum levels of sex hormones were measured by chemiluminescence, and plasma concentrations of organochlorine (OC) pesticides and the level of dialkyl phosphates metabolites (DAPs) of organophosphorus agrochemicals presented in urine were measured through gas chromatography-mass spectrometry. Around 41.6 % of the participants presented some alteration in their hormonal levels, mainly of follicle-stimulating hormone and progesterone. Of these, OC pesticides in plasma were detected in 62 % (ΣOC = 1651.25 ng/g of lipid), and 66 % had detectable levels of DAPs (ΣDAP = 153.82 mg/g of creatinine). Together, these results suggest damage to the endocrine system that could be generated by exposure to a mixture of OC and organophosphorus pesticides could generate.

Organochlorine Pesticides and Polychlorinated Biphenyls in American Oystercatchers Nesting along the Texas Gulf Coast

The American Oystercatcher (Haematopus palliatus palliatus) is an important breeding species along the Texas Gulf Coast, particularly between Galveston Bay and Corpus Christi, Texas, USA. American Oystercatchers are considered a species of greatest conservation need and are on the priority list for conservation by the National Fish and Wildlife Foundation. American Oystercatchers feed mainly on oysters (Ostreidae) and other bivalves, which are known to accumulate significant amounts of pollutants. We determined accumulation and potential effects of environmental contaminants, particularly organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs) in blood of American Oystercatchers nesting along the Texas Gulf Coast, USA during 2012 and 2013. Plasma concentrations of OCs and PCBs were low. The most commonly detected OC pesticides were HCB, HCH, α chlordane, endosulfan, methoxychlor, p,p'-DDD, and p,p'-DDE. Total p,p'-DDE concentrations ranged from 2-10 ng/mL ww and total PCB concentrations ranged from 2-54 ng/mL ww. Mean p,p'-DDE concentrations were similar among regions; however, total PCBs were significantly greater (P = 0.0056) in blood from adult birds from West Galveston Bay, Texas, USA in 2013 than in blood from young collected in 2012, mostly also from West Galveston Bay. Overall, concentrations of OC pesticides in plasma were low; however, some PCB concentrations were above the NOAEC levels that have been associated with normal reproduction in other bird species.

Dispersive liquid–liquid microextraction based on solidification of deep eutectic solvent droplets for analysis of pesticides in farmer urine and plasma by gas chromatography–mass spectrometry

A new disperser–less, centrifuge–less, ice–bath less and deep eutectic solvent–based solidification of organic droplets dispersive liquid–liquid microextraction performed in a laboratory–made extraction apparatus coupled with gas chromatography–mass spectrometry has been developed for the analysis of ten pesticides in plasma and urine samples. For this purpose, a glass tube containing a glass membrane filter was fabricated and a new synthesized deep eutectic solvent with density lighter than water was used as an extractant. The extraction solvent was forced to pass through the glass filter under N2 stream and it was dispersed as the fine droplets in the sample solution. In this step, the analytes were transferred into the droplets. Due to low density of the extractant, it was collected on top of the sample solution without centrifugation. After performing the validation of the method, low limits of detection in the ranges of 2–17 and 4–36 ng L−1 in urine and plasma were obtained, respectively. Extraction recoveries were in the range of 79–97%. Enrichment factors were obtained from 379 to 485 in urine and 158–194 in plasma. Finally, plasma and urine samples of farmers were effectively analyzed using the method.

Selective extraction of organophosphorous pesticides in plasma by magnetic molecularly imprinted polymers with the aid of computational design

MIP-APTES-MNP was designed and characterized to selectively extract OPPs from plasma samples.

A single method for detecting 11 organophosphate pesticides in human plasma and breastmilk using GC-FPD.

Organophosphate (OP) pesticides are widely used for crop protection in many countries including Thailand. Aside from causing environmental contamination, they affect human health especially by over-stimulating of the neurotransmission system. OP pesticides, as with other non-persistent pesticides, degrade quickly in the environment as well as are metabolized quite rapidly in humans. Assessing human exposures to these compounds requires analytical methods that are sensitive, robust, and most importantly, suitable for specific laboratory settings. The aim of this study was to develop and validate an analytical method for measuring 11 OP pesticide residues in human plasma and breast milk. Analytes in both plasma and breast milk samples were extracted with acetone and methylene chloride, cleaned-up using aminopropyl solid phase extraction cartridges, and analyzed by gas chromatography with flame photometric detection. The optimized method exhibited good linearity, with the coefficients of determination of 0.996-0.999 and <7% error about the slope. Extraction recoveries from spiked plasma and breast milk samples at low and medium concentrations (0.8-5.0 and 1.6-10ngmL(-1), respectively) ranged from 59.4% (ethion) to 94.0% (chlorpyrifos). Intra-batch and inter-batch precisions ranged from 2.3-18.9% and 5.8-19.5%, respectively. Method detection limits of plasma and breast milk ranged from 0.18-1.36 and 0.09-2.66ngmL(-1), respectively. We analyzed 63 plasma and 30 breastmilk samples collected from farmworkers in Chiang Mai Province to determine the suitability of this method for occupational exposure assessment. Of the 11 pesticides measured, seven were detected in plasma samples and five were detected in breast milk samples. Mass spectrometry was used to confirm results. Overall, this method is rapid and reliable. It offers the laboratories with limited access to mass spectrometry a capacity to investigate levels OP pesticides in plasma and breastmilk in those occupationally exposed for health risk assessment.

Determination of the Genotype and Phenotype of Serum Paraoxonase 1 (PON1) Status in a Group of Agricultural and Nonagricultural Workers in the Coquimbo Region, Chile

Paraoxonase 1 (PON1) is a glycosylated enzyme that is found associated with high-density lipoproteins in blood. In addition to its endogenous antioxidant role, this enzyme is also involved in hydrolysis of organophosphate (OP) pesticides in plasma. PON1 activity shows great variability in the population as a result of a polymorphism in the coding sequence that is expressed as a Glu(Q)/Arg(R) substitution at position 192 of the amino acid sequence. The aim of this study was to determine the activity levels (phenotype) and genotype of PON1 in a group of 85 agricultural workers occupationally exposed to OP pesticides and compared to 97 control subjects without occupational exposure. Allelic and genotypic frequencies of PON1Q192R polymorphism, as well as their catalytic activities, were established for the first time in a group of agricultural Chilean workers. The Q allele was more frequently represented in our studied population (approximately 60%). The Q allele is less efficient than the R allele at metabolizing chlorpyrifos (CPF), the most widely used OP pesticide in the geographical areas where samples were obtained. Further, a large interindividual variability in PON1 activity was observed, suggesting wide variation of individual susceptibility to CPF, an issue that needs to be considered in human monitoring studies.

Levels of organochlorine pesticides in blood plasma from residents of malaria-endemic communities in Chiapas, Mexico.

Organochlorine (OC) pesticides have been extensively used for pest control in agriculture and against malaria vectors in the region of Soconusco, Chiapas, in southern Mexico. Our study aimed to identify whether the inhabitants of four Soconusco communities at different locations (i.e., altitudes) and with different history of use of OC pesticides, have been similarly exposed to residues of these pesticides. In particular, we analyzed the potential relationship between levels of OC pesticides in plasma and the age, gender, and residence of the study population (n = 60). We detected seven pesticides in total (γ-HCH, β-HCH, heptachlor, p,pʹ-DDE, p,p'-DDT, β-endosulfan, endrin aldehyde). Of these, p,pʹ-DDE and β-endosulfan were the most frequently found (in 98% and 38% of the samples, respectively). The low-altitude (<20 m above sea level; masl) and mid-altitude (520 masl) locations had the highest levels of p,pʹ-DDE, with geometric means of 50.6 µg/L and 44.46 µg/L, respectively. The oldest subjects (>60 years) had the highest p,pʹ-DDE level (56.94 ± 57.81 µg/L) of all age groups, while men had higher p,pʹ-DDE (34.00 ± 46.76 µg/L) than women. Our results demonstrate that residents of the Soconusco region are exposed to p,pʹ-DDE because of high exposure to DDT in the past and current environmental exposure to this DDT-breakdown product.

Polychlorinated biphenyls and organochlorine pesticides in plasma of older Canadians

No nationwide study has ever measured polychlorinated biphenyl (PCB) and organochlorine pesticide (OCP) body burden in Canadians aged 65 years and over. The objective of this study was to determine plasma concentrations of PCB congeners and OCPs in participants from a sub-cohort of the Canadian Study of Health and Aging and to examine the effects of socio-demographic, anthropometric and lifestyle characteristics on selected organochlorine concentrations. Archived plasma samples collected from 2023 subjects were analyzed by gas chromatography−mass spectrometry using negative chemical ionization for 15 PCB congeners and 11 OCPs. Descriptive statistics were used to report PCB congeners and OCP plasma concentrations. Multivariate models were used to study whether age at blood collection, sex, education, body mass index, rural residence, geographic region, smoking status and alcohol intake influences PCB 153, the most abundant congener, and the major OCP (beta-hexachlorocyclohexane, hexachlorobenzene, trans-nonachlor, p,p′-DDE) plasma concentrations. Statistical analyses were restricted to 1979 subjects and 17 organochlorine compounds for which at least 50% of the samples had concentrations above the limit of detection. Of these, 775 were men (mean age: 82.2 years) and 1204 were women (mean age: 84.6 years). The median concentrations (ng/g lipid) of PCB 153 in the plasma of men and women were 70.9 and 75.4, respectively. The levels of the sum of PCBs and the sum of dioxin-like PCBs were 276 and 31.3 for men, and 300 and 45.5 for women, respectively. The median concentrations (ng/g lipid) of p,p′-DDE, the most abundant OCP, were 565 for men and 828 for women. All compounds were positively and significantly intercorrelated (rs=0.39–0.99; p<0.001). Except for trans-nonachlor, the multivariate models revealed that age and male sex were the determining characteristics that showed, respectively, strongly positive and negative associations with selected organochlorine concentrations. These plasma concentrations from a large population based study can be considered as baseline data for body burdens of older Canadians.

Assessment of oxidative stress due to exposure to pesticides in plasma and urine of traditional limited-resource farm workers: Formation of the DNA-adduct 8-hydroxy-2-deoxy-guanosine (8-OHdG)

The objective of this study was to assess the risk of genotoxicity caused due to oxidative stress using plasma and urinary levels of 8-hydroxy-2-deoxyguanosine (8-OHdG) in farm workers for six months during a growing season. Blood and urine samples were collected once a month for six months (June to November 2003) from farm workers (n = 15) and urban unexposed controls (n = 10). Plasma and urinary levels of 8-OHdG were evaluated by Enzyme Linked Immunosorbent Assay (ELISA) technique. There was no significant difference in the urinary levels of 8-OHdG between the farm workers and the control group, but there was an approximately four-fold increase in mean values of plasma 8-OHdG levels in the farm worker group (P ≤ 0.05).

Polychlorinated Biphenyls and Organochlorine Pesticides in Plasma and the Embryonic Development in Lake Erie Water Snakes (Nerodia sipedon insularum) from Pelee Island, Ontario, Canada (1999)

From three locations along a 34-km shoreline of Pelee Island, Ontario, 30 gravid female Lake Erie water snakes (Nerodia sipedon insularum) were sampled to determine the organochlorine (OC) contaminant levels in plasma and the number of live and dead embryos present in the body cavity. Plasma was analyzed for 59 polychlorinated biphenyl (PCB) congeners and 14 organochlorine pesticides. Concentrations of pesticides were low (< or =0.1 ng/g wet wt) in all snakes, but there was significant variation in mean PCB concentrations in plasma from among the sampling locations on Pelee Island. Snakes (n = 5) from the West shore and dock area of the island had significantly higher PCB concentrations (90.4 +/- 15.0 ng/g wet wt) in plasma than those from Lighthouse Point (n = 5; 34.4 +/- 13 ng/g wet wt) and the south shore of the island (n = 5; 29.4 +/- 16.3 ng/g wet wt). Body mass of the female snakes ranged from 252 to 880 g, and mean masses were not significantly different among sample sites. The number of live embryos found ranged from 13 to 46 female snakes and no dead embryos were detected. There were significant positive correlations among body mass, snout-vent length, and number of young per female. There were no significant correlations among body mass, snout-vent length, number of young per female, or per-gram body mass of female snakes and contaminant concentrations in plasma. It was concluded that an interim estimate of a no-effect level on embryonic survival in N. sipedon insularum may be a maximum average concentration of 90.4 ng/g wet wt PCBs and a maximum average concentration of 3.6 ng/g wet wt p,p'-dichloro-diphenyl-dichloroethylene in plasma.