Publications by authors named "Stefan M Waliszewski"

Organochlorine pesticides are persistent organic pollutants (POPs) that can enter the body through environmental exposure and food consumption. The aim of this study was to investigate the influence of parity and breast milk consumption on dichlorodiphenyltrichloroethane (DDT) concentrations in women from Southern Mexico. Gas chromatography was used to detect o,p'-DDT, p,p'-DDT, and p,p'-dichlorodiphenyldichloroethylene (DDE) in milk samples.

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This study aims to establish the relationship between the consumption of certain foods and the presence of organochlorine pesticides in human milk. A total of 167 samples of breastmilk were collected. Sample analysis was carried out by gas chromatography with electron capture detector.

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The population that lives in areas where organochlorine pesticides were spread in the past is still exposed to them through contaminated food, particulate matter, and vapors. Due to their lipophilic properties and resistance to metabolic reactions, they accumulate in tissues and fluids rich in lipids. The aim of the study was to monitor the concentrations of organochlorine pesticides in forensic adipose tissue samples of adult inhabitants of Veracruz City, Mexico, and compare their time trend levels from 1988 to 2014.

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The aim of the study was to evaluate genotoxic effects of Pirimor-50®, a pirimicarb-based formulation (50 % active ingredient), in human lymphocyte cultures and Vicia faba root meristems. Furthermore, the objective was to examine a combined influence of insecticide treatment with mammalian microsomal S9 and vegetal S10 metabolic fractions or S10 mix metabolic transformation extracts (after Vicia faba primary roots treatment with Pirimor-50®). We used sister chromatid exchange assay-SCE and measured cell cycle progression and proliferation (proportion of M1-M3 metaphases and replication index ratio-RI).

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Gasoline is a blend of organic compounds used in internal combustion engines. Gasoline-station attendants are exposed to gasoline vapors, which pose a potentially mutagenic risk. According to the International Agency for Research on Cancer, exposure to gasoline and engine exhaust is possibly carcinogenic to humans.

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This study evaluated direct and metabolic genotoxic effects caused by Lannate-90®, a methomyl-based formulation (90 % active ingredient), in human lymphocyte cultures using sister chromatid exchange assay (SCE). Two processes were used for the plant promutagens evaluation: in vivo activation, applying the insecticide systemically in plants for 4 h and subsequently adding plant metabolites containing extracts to lymphocyte cultures; and in vitro activation, where the insecticide was incubated with Vicia faba S10 mix plus human lymphocyte culture. Direct treatment with the insecticide significantly increased SCE frequency in human lymphocytes (250-750 mgL-1), with cellular death observed at 1000 mgL-1 concentration.

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This study was conducted with the objective of determining whether there is a depuration of organochlorine pesticides in breast milk according to breastfeeding time. In total, 171 samples from mothers that lived in the State of Guerrero, Mexico were analyzed. There was a weak negative relationship between pp'DDE (r = -0.

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Burning the sugar cane field before harvesting has a negative impact on both air and human health, however this issue had not been explored in Mexico. The objective of this work was to determine the chromosomal damage in workers from sugar cane burning fields in Sinaloa, México. To this purpose, we analyzed 1000 cells of buccal exfoliated epithelia from 60 exposed workers and 60 non-exposed controls to determine micronucleus frequencies and other nuclear abnormalities.

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Organochlorine pesticides, due to their hydrophobic nature and persistence, accumulate in tissues rich in lipids, which had been used as a biomarker for environmental pollution. In humans, organochlorine pesticides are continuously circulating and equilibrating among body compartments. The objective of the study was to evaluate the concentrations of organochlorine pesticides in blood serum and compare their levels to the total lipid contents in Veracruz, México inhabitants.

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Glutamate, the major excitatory amino acid, activates a wide variety of signal transduction cascades. This neurotransmitter is involved in photic entrainment of circadian rhythms, which regulate physiological and behavioral functions. The circadian clock in vertebrates is based on a transcription-translation feedback loop in which Brain and muscle aryl hydrocarbon receptor nuclear translocator (ARNT)-like protein 1 (BMAL1) acts as transcriptional activator of others clock genes.

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Organochlorine pesticides have been used in Mexico in malaria control programs and against ectoparasites. The objective of this study was to compare the levels of organochlorine pesticides: HCB, α-β-γ-HCH, pp'-DDE, op'-DDT and pp'-DDT in adipose tissue of female inhabitants from three Mexican states: Veracruz, Puebla and Tabasco. Data analyses indicated higher β-HCH levels in Puebla inhabitants.

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In Mexico, organochlorine pesticides were used in public health and agriculture programs, causing chronic exposure to the population. Human breast milk samples were collected from 171 mothers who were residents from Guerrero, Mexico. Analysis was carried out by gas chromatography.

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Organochlorine pesticides (OCPs) can cause environmental damage and human health risks since they are lipophilic compounds with high resistance to degradation and long half-lives in humans. As most persistent OCPs have been banned years ago, it is expected to find these compounds at trace levels in environment. Therefore, increasingly sensitive and reliable analytical techniques are required to ensure effective monitoring of these compounds.

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In rabbit pups, nursing by the mother is the prevailing entraining signal for their circadian rhythms during at least the first two weeks of life. Therefore, they are considered a natural model of food anticipatory activity. However, the photic entrainment of the circadian system in rabbit pups during this developmental stage is not well understood.

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The objective of this study was to determine the levels of organochlorine pesticides HCB, α-β-γ-HCH, p,p'-DDE, o,p'-DDT and p,p'-DDT in 150 adipose tissue of inhabitants of Tabasco, Mexico. The following pesticides were detected: p,p'-DDE in 100% of samples at mean 1.034 mg/kg; p,p'-DDT in 96.

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Rabbit pups represent a natural model of food anticipatory activity (FAA). FAA is the behavioral output of a putative food entrainable oscillator (FEO). It had been suggested that the FEO is comprised of a distributed system of clocks that work in concert in response to gastrointestinal input by food.

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The objective of this study was to determine the levels of organochlorine pesticides HCB, α-β-γ-HCH, pp'DDE, op'DDT and pp'DDT in adipose tissue of females living in Puebla, Mexico. Organochlorine pesticides were analyzed in 75 abdominal adipose tissue samples taken during 2010 by autopsy at the Forensic Services of Puebla. The results were expressed as mg/kg on fat basis.

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The objective of the present study was to monitor the levels of organochlorine pesticides HCB; α-, β-, γ-HCH; pp'DDE; op'DDT; and pp'DDT in blood serum of Veracruz, Mexico inhabitants. Organochlorine pesticides were analyzed in 150 blood serum samples that constituted that which remained after clinical analyses, using gas chromatography-electron-capture detection (GC-ECD). The results were expressed as milligrams per kilogram on fat basis and micrograms per liter on wet weight.

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The objective of the present study was to monitor the levels of organochlorine pesticides HCB, α-β-γ-HCH, pp'DDE, op'DDT and pp'DDT in 150 adipose tissue samples of Veracruz, Mexico inhabitants. In analyzed samples, the following pesticides were detected: p,p'-DDE in 100% of the samples at mean 1.643 mg/kg; p,p'-DDT in 99.

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The black carbon is a pollutant species primarily emitted from the combustion of fossil fuels (diesel). Their concentrations associated to PM2.5 were monitoring at two sites in the city of Guadalajara.

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Since the discovery of insecticide properties of DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane) and HCH (hexachlorocyclohexane), they have provided great benefits to humans in sanitary actions to combat the spread of infection-borne disease vectors. Public Health Programs in Mexico used DDT and HCH until 1999 as the insecticides of choice to control disease-transmitting organisms. Because of their persistence and accumulative properties, organochlorine pesticides bioconcentrate in lipids of the human body, reflecting the rate of environmental exposure.

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The scientific basis for the statement that plants and their active constituents play an important role in the prevention of chronic and degenerative diseases is continously advancing. The object of the present study was to evaluate the effect of Hibiscus sabdariffa L. dried calyx ethanolic extract on the serum lipid profile of Sprague-Dawley rats.

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Samples of human blood sera (N = 118) for the determination of organochlorine pesticide levels were obtained at autopsy from auto accident victims in Veracruz, Mexico, during the years 2000 and 2001. The presence of hexachlorobenzene (HCH), beta-hexachlorocyclohexane (beta-HCH), 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (p,p'-DDT), and o,p'-DDT was confirmed by gas-liquid-electron-capture detection chromatography. During the years 2000 and 2001, the respective mean levels of (a) HCB, (b) beta-HCH, (c) p,p'-DDE, (d) o,p'-DDT, (e) p,p'-DDT, and (f) total DDT were (a) 2.

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The aim of our study was the induction of sister chromatid exchanges (SCE) in human lymphocytes in vitro and in root tip meristems of Vicia faba to evaluate the genotoxic effects of metribuzin and ametryn. Direct treatments of these herbicides on human lymphocytes in vitro applied 24 h after the beginning of culture did not induce SCE; however, they showed a cytotoxic effect in the cultures expressed as cellular death. On the contrary, when extracts of V.

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The organochlorine pesticides are lipophilic and persistent and tend to accumulate in soils and growing plants. The contamination of growing plants occurs by adhesion of volatile substances from the air to the plant surface and by the migration of contaminants through xylem in inner ascendant transport. Persistent organochlorine pesticides (HCB, alpha,gamma-HCH, pp'DDE, op'DDT, pp'DDT) levels were determined in soils and rye plants.

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