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F Olea-Serrano

Publications and source records attributed to F Olea-Serrano.

12 recordsLinked to original sources

Organochlorine pesticides in placentas from Southern Spain and some related factors.

During pregnancy, lipophilic xenobiotics stored in maternal adipose tissue can be mobilized and enter her blood circulation and reach the placenta. This study measured residues of oestrogen-mimicking organochlorine pesticides (OCs) in 150 placenta samples from women in Southern Spain. OCs were extracted from placenta by solid-liquid technique and purified by preparative liquid chromatography. Gas chromatography/electron-capture detection and mass spectrometry were used to identify and quantify p,p'-DDT and congeners/metabolites, endosulphan and congeners/metabolites, lindane, aldrin/dieldrin/endrin, hexachlorobenzene, methoxychlor and mirex. A mean of eight pesticides per placenta were detected (range, 3-15 pesticides). Endosulphan-ether, endosulphan-diol, endosulphan-I, p,p'-DDE, o,p'-DDD, p,p'-DDT, o,p'-DDT and lindane were detected in >or=50% of samples; p,p'-DDE was the most frequent (96.03%), followed by endosulphan-diol (76.86%) and lindane (74.17%). Presence of more pesticides was significantly associated with lower birth weight. Mean concentration of p,p'-DDE was 2.37+/-2.80 ng/g of placenta or 76.62+/-104.85 ng/g of lipid. Higher maternal body mass index was significantly associated with higher endosulphan concentrations in placenta, and greater maternal weight gain was significantly associated with higher p,p'-DDE concentrations. Prenatal exposure to OC xenoestrogens may be a causative factor in adverse reproductive health trends, and further studies are required to identify and describe pathways of this exposure to enhance preventive measures.

Adult↗

Organochlorine pesticides in serum and adipose tissue of pregnant women in Southern Spain giving birth by cesarean section.

Since the appearance of DDT, increasingly potent insecticides have been developed to overcome the resistance developed by insects to successive products. Pesticides are also used in public health programs to control disease vectors. Despite legislation to control the use of certain products, they repeatedly appear in the adipose tissue, milk and serum of human populations. The present study determined the presence of organochlorine molecules in the adipose tissue, serum, and umblical cord of women giving birth by cesarean section in order to establish a possible correlation in organochlorine molecule content between these biological compartments and to examine fetal exposure to molecules with hormonal effects. Presence of nine organochlorines was detected by GC/ECD and confirmed by GC/MS. Highly significant differences (p<0.000) were observed between adipose tissue and maternal serum in concentrations of lindane, HCB, DDE, DDD, and endosulfan but not (p>0.5) in concentrations of endosulfan II or endosulfan sulfate. Only DDE concentrations differed (p<0.001) between maternal serum and umbilical cord serum. An association between pp'DDE and op'DDT was observed in maternal serum (p<0.094). An association in pp'DDE and pp'DDD content was found between adipose tissue and umbilical cord serum, and in pp'DDT content between adipose tissue and maternal serum. Results obtained indicate that exposure can be measured solely in serum when relatively high concentrations of pesticides are present.

Adipose Tissue↗

Determination of endocrine-disrupting pesticides and polychlorinated biphenyls in human serum by GC-ECD and GC-MS-MS and evaluation of contributions to the uncertainty of the results.

The chemicals endosulfan-alpha, endosulfan-beta, endosulfan sulfate, endosulfan ether, endosulfan lactone, PCB-21, PCB-48, PCB-61, and PCB-136 have been determined in 100 serum samples from women living in agricultural areas of Almería (Spain). The study includes a surgically treated breast cancer patient and a matching group of women with no sign of estrogenic-dependent disease. The determination was performed by gas chromatography with electron capture detection (GC-ECD) and tandem mass spectrometry (GC-MS-MS). Recovery, precision, linear range, detection limit (LOD), and quantification limit (LOQ) were calculated for each pesticide as was the expanded uncertainty (U). The method was evaluated for our laboratory and could be applied to subsequent results with relevant quality-control data. Comparison of the results was performed. The advantage of MS-MS over ECD for determination of endocrine-disrupting compounds in complex matrices is presented. The most commonly encountered pesticide was endosulfan-alpha. Endosulfan-beta and the PCB-48 congener were detected at concentrations lower than their LOQ. Endosulfan sulfate, endosulfan ether, endosulfan lactone, PCB-21, PCB-61 and PCB-136 were not found in any of the serum samples analysed.

Breast Neoplasms↗

Diet and organochlorine contaminants in women of reproductive age under 40 years old.

The diet of the breast-feeding mother impacts on the quality and quantity of the milk that she feeds her child. Milk can be a vehicle for toxins, such as drugs and their metabolites, viruses, nicotine, caffeine, alcohol, and organochlorine molecules such as PCBs, DDT, HCB, HCH and dioxins, which can harm the health of the breast-feeding child. The 24-h recall diet was considered appropriate to adequately study the diet of breast-feeding mothers and was used in the present preliminary study to establish the possible relationship between the food items consumed and the presence of pesticides in her milk. Two groups of randomly selected healthy breast-feeding volunteers aged between 17 and 35 years from two different areas were recruited: 34 from intensive agriculture zone, El Ejido (Almeria), from the "Hospital de Poniente" and 21 urban zone, the city of Granada, from the "Clinico" University Hospital. Application of the Spearman Correlation Test to the results from Almeria showed a certain positive correlation between the total intake of fats and both the p,p'DDD (rho=0.53, p< or =0.05) and methoxychlor (rho=0.48, p< or =0.05) in mature milk, and between the energy supplied by vegetables and the endosulfan-lactone in mature milk (rho=0.50, p< or =0.05). Among the group of breast-feeding women from Granada, there was a strong correlation between the intake of fats and both the p,p'DDT in transition milk (rho=0.90, p< or =0.05) and the p,p'DDD in mature milk (rho=0.90, p< or =0.05). In conclusion, there is a statistically significant relationship between the consumption of fatty foods and some organochlorine molecules and between the consumption of vegetables and pesticides, and the latter relationship occurs in Almeria but not in Granada.

Adolescent↗

Trace determination of alpha- and beta-endosulfan and three metabolites in human serum by gas chromatography electron capture detection and gas chromatography tandem mass spectrometry.

Endosufan, alpha and beta, and three conversion products, sulphate, ether and lactone, were simultaneously determined in human serum by means of an analytical procedure which combines extraction with organic solvents, clean-up with H(2)SO(4) and by liquid column chromatography, and detection by gas chromatography (GC) using electron capture detection (ECD) and tandem mass spectrometry (MS/MS). The procedure was validated and the values of some merit figures, such as linear range, detection and quantitation limits, accuracy, precision and recovery, obtained with the GC/ECD and the GC/MS/MS methods, were compared. The lower limits of detection in GC/ECD and GC/MS/MS were 0.03 and 0.05 microg I(-1), respectively. The recovery of the pesticides at the 20 microg I(-1) concentration level was 60-65%, with the exception of endosufan alpha. Recovery studies at higher levels (100 and 200 microg I(-1)) were independent of pesticide concentration in serum samples. The application of the proposed analytical methodology to the determination of endosulfans and their metabolites in real samples was tested by analyzing serum samples from a population living in agricultural areas of Almeria (Spain). The results show the advantage of MS/MS over the ECD detector in the analysis of serum samples where matrix interferences can be confused with target pesticides.

Endosulfan↗

Quantitative determination of endocrine- disrupting polychlorinated biphenyls and organochlorinated pesticides in human serum using gas chromatography with electron-capture detection and tandem mass spectrometry.

A sensitive, selective and reliable procedure was developed and validated to determine organochlorinated compounds, which have endocrine-disrupting effects, in human serum. Target compounds were selected between polychlorinated biphenyls and organochlorinated pesticides. Sample workup consisted of (1) extraction of serum with organic solvents, (2) clean-up of the organic extract using acid treatment with H(2)SO(4), (3) elution of the cleaned-up extract through a liquid column chromatographic system and (4) analysis of the fraction eluted by gas chromatography with electron capture detection (ECD) and tandem mass spectrometry (MS/MS) detection. Performance characteristics, such as linearity, sensitivity, precision, accuracy and recovery, of both chromatographic methods were studied. The proposed analytical methodology was applied to determine the target compounds in serum samples from women living in agricultural areas of Almería (Spain). The results show the advantage of MS/MS over ECD in the analysis of real human serum samples where matrix interferences can be confused with target pesticides.

Blood Chemical Analysis↗

Assays to measure estrogen and androgen agonists and antagonists.

Substantial evidence has surfaced on the hormone-like effects of many xenobiotics in fish, wildlife and humans (Colborn et al., 1993). The endocrine and reproductive effects of xenobiotics are believed to be due to their 1) mimicking the effects of endogenous hormones such as estrogens and androgens, 2) antagonizing the effects of normal, endogenous hormones, 3) altering the pattern of synthesis and metabolism of natural hormones, and 4) modifying the hormone receptor levels. Estrogen mimics (xenoestrogens) are among the environmental chemicals found to cause reproductive impairment in wildlife and humans. All of these compounds were found to be estrogenic long after they had been released into the environment. A single causal agent can be identified in cases in which humans have had occupational exposures, whereas in cases where wildlife have shown signs of reproductive damage the exposure is usually a combination of endocrine disruptors that may have acted cumulatively. It has been hypothesized that environmental estrogens may play a role in the decrease of human semen quantity and quality of human semen during the last 50 years. They may also be partly responsible for the increased incidence of testicular cancer and cryptorchidism in males and breast cancer incidence in both females and males in the industrialized word. Testing this hypothesis will require: 1) the identification of xenoestrogens among the chemicals present in the environment, 2) the development of a methodology to assess the interactions among mixtures of xenoestrogens to which humans are exposed, and 3) the discovery of markers of estrogen exposure. The development of fast and sensitive bioassays is central to the achievement of these three goals.

Androgen Antagonists↗

The estrogenicity of bisphenol A-related diphenylalkanes with various substituents at the central carbon and the hydroxy groups.

The chemical structure of hydroxylated diphenylalkanes or bisphenols consists of two phenolic rings joined together through a bridging carbon. This class of endocrine disruptors that mimic estrogens is widely used in industry, particularly in plastics. Bisphenol F, bisphenol A, fluorine-containing bisphenol A (bisphenol AF), and other diphenylalkanes were found to be estrogenic in a bioassay with MCF7 human breast cancer cells in culture (E-SCREEN assay). Bisphenols promoted cell proliferation and increased the synthesis and secretion of cell type-specific proteins. When ranked by proliferative potency, the longer the alkyl substituent at the bridging carbon, the lower the concentration needed for maximal cell yield; the most active compound contained two propyl chains at the bridging carbon. Bisphenols with two hydroxyl groups in the para position and an angular configuration are suitable for appropriate hydrogen bonding to the acceptor site of the estrogen receptor. Our data suggest that estrogenicity is influenced not only by the length of the substituents at the bridging carbon but also by their nature. Because diphenylalkane derivatives are widespread and their production and use are increasing, potential exposure of humans to estrogenic bisphenols is becoming a significant issue. The hazardous effects of inadvertent exposure to bisphenol-releasing chemicals in professional workers and the general populations therefore deserve investigation.

Benzhydryl Compounds↗

Estrogenicity of resin-based composites and sealants used in dentistry.

We tested some resin-based composites used in dentistry for their estrogenic activity. A sealant based on bisphenol-A diglycidylether methacrylate (bis-GMA) increased cell yields, progesterone receptor expression, and pS2 secretion in human estrogen-target, serum-sensitive MCF7 breast cancer cells. Estrogenicity was due to bisphenol-A and bisphenol-A dimethacrylate, monomers found in the base paste of the dental sealant and identified by mass spectrometry. Samples of saliva from 18 subjects treated with 50 mg of a bis-GMA-based sealant applied on their molars were collected 1 hr before and after treatment. Bisphenol-A (range 90-931 micrograms) was identified only in saliva collected during a 1-hr period after treatment. The use of bis-GMA-based resins in dentistry, and particularly the use of sealants in children, appears to contribute to human exposure to xenoestrogens.

Adult↗

[Perspectives on endocrine disruption].

Two decades ago, reports of alterations in the reproductive function of some wild animal species and clear evidence of human and animal exposure to chemical substances with hormonal activity agonist and antagonist generated what is known now as the hypothesis of endocrine disruption. This is an emerging environmental health problem that has challenged some of the paradigms on which the control and regulation of the use of chemical compounds is based. The need to include in routine toxicology tests new research objectives that specifically refer to the development and growth of species and to the homeostasis and functionality of hormonal systems, has served to complicate both the evaluation of new compounds and the re-evaluation of existing ones. The repercussions on regulation and international trade have not taken long to be felt. On both sides of the Atlantic, screening systems for endocrine disrupters have been designed and established, and research programmes have been launched to characterise and quantify adverse effects on human and animal health and to develop preventive measures.

Animals↗

Inadvertent exposure to xenoestrogens in children.

This article reviews previous studies and presents new data on pesticide exposure in order to provide some indications of the extent and significance of childhood exposure to xenoestrogens, including pesticides, epoxy resins, and polycarbonates. After more than four decades of pesticide use, little is known about their adverse effects on health. There is a need to address the potential risks associated with the current contamination of water, soils, and foods in many agricultural areas. In southeastern Spain, along the Mediterranean coast, extensive areas alongside residential zones are devoted to intensive farming in plastic greenhouses, with the use of large amounts of pesticides. Human tissue samples have been investigated for pesticide residues. Samples of fat from children living in farm areas contained a total of 14 pesticides, including lindane, HCH, heptachlor, aldrin, dieldrin, endrin, endosulfan, o,p'-DDE, and o,p'-DDD, among others. Of the 113 samples studied, 43 were positive for one or more pesticides, some of which have estrogenic activity. The number of new substances that mimic the action of endogenous estrogens is increasing rapidly. These endocrine-disrupting chemicals are not restricted to pesticides. Several different compounds used in the food industry, in plasticizers, and in dental restorations are also estrogenic. The few studies that have investigated their effects in humans all indicate that concerns are warranted. If there is indeed an association between zexposure to substances with hormone-disruptive activity and certain disorders of sexual maturation, the incidence of such disorders should be greater in areas where exposure to agents with this activity is high. We used a spatial ecological design to search for variations in orchidopexy rates and to analyze relationships between these differences and geographical variations in exposure to pesticides. Our results are compatible with a hypothetical association between exposure to hormone-disruptive chemicals and the induction of cryptorchidism. Several methodological limitations in the study design make it necessary to evaluate the results with caution. In conclusion, a closer scrutiny is required to determine whether epoxy resins and polycarbonates contribute, together with estrogenic pesticides, to the exposure of human consumers, especially children, to xenoestrogens.

Adipose Tissue↗