Effect of phthalates exposure during perinatal period on hormonal profile in Mexican males during their first months of life.

Phthalates affect development of male reproductive system acting as an antiandrogenic agents. We sought to explore if perinatal exposure to phthalates could alter male hormone levels in humans during the first months of life. A cohort of 83 pregnant women and their male infants were studied. Five phthalate metabolites were measured in the mother's urine during the first, second, and third trimesters of pregnancy and during the first, third, and sixth months of life in the infants. Luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone and inhibin B were analyzed. Association between phthalate exposure and hormone variation was assessed using regression models for longitudinal data. Mono-butyl phthalate reduced FSH concentration (ß = -0.0012 international units [IU]/L, p < 0.01), mono-ethylhexyl phthalate reduced inhibin B (ß = -0.0094 pg/mL, p = 0.02), monoethyl phthalate reduced testosterone (ß = -0.0071 ng/L, p = 0.07), mono-ocytl phthalate reduced LH (ß = -0.0041 IU/L, p = 0.13). No effects were observed for exposure to mono-methyl phthalate. Our results are consistent with the findings in animal and human studies. Special precaution should be taken when measuring phthalate exposure in susceptible populations such as pregnant women and infants.

Phthalates exposure during pregnancy a study in a Mexican cohort.

A prospective cohort study was conducted to measure the concentration levels of three primary phthalate metabolites (MBP, MEHP, MEP) during pregnancy in a group of women from the State of Mexico. The urinary concentration levels of the three phthalate primary metabolites were measured by gas chromatography mass spectrometry during the first, second and third trimesters of pregnancy. The geometric mean and 95 % CI for MBP was 20.38 µg/mL (15.35-27.09); for MEHP 13.43 µg/mL (8.93-20.20), and MEP 52.47 µg/mL (39.88-69.04) adjusted to one g of creatinine. No significant trends were observed among the studied metabolites during the pregnancy period. MBP was higher in less educated women, while women who resided in industrialized zones showed higher levels of MEHP and MEP than women from non-industrialized zones. Consumption of plastic bottled beverages was associated with MBP and MEHP phthalate exposure. Women who used non-registered brands of plastic food containers for storage or for microwave oven use showed the highest levels of MBP and MEP phthalates. The pregnant women in our study were exposed to the three studied primary phthalate metabolites, and this could present a risk to their newborns. To better integrate public health policies, major exploration of potential exposure sources and effects at the regional level is required.

Night Shift Work and Risk of Breast Cancer in Women.

BACKGROUND: Night shift work involving circadian disruption has been associated with increased breast cancer rates in some epidemiological studies, but the evidence is still on debate. AIM OF THE STUDY: The objective of this study is to assess the association between night shift work and breast cancer in Mexican women. METHODS: A Case-control study was conducted with incident cases of breast cancer at the Instituto de Seguridad Social del Estado de México y Municipios. Cases were interviewed about past exposures prior to the final diagnosis. Controls were women without breast cancer matched on multiple sociodemographic characteristics. RESULTS: 101 cases and 101 matched controls were interviewed; this small sample size provided consistent, but wide estimates of the assessed associations. The multivariate conditional logistic regression showed that breast-feeding was associated with reduced risk for breast cancer (OR 0.12; 95% CI: 0.02-0.60); women who experienced early menarche (12 years) were more likely to develop breast cancer (OR 18.58; 95% CI 18: 2.19-148). Women who worked at night were more likely to develop breast cancer compared to women who never did (OR = 8.58; 95% CI: 2.19-33.8). CONCLUSIONS: Our results are consistent with studies from other countries, which positively associated night shift work with breast cancer.

A Pilot Study Evaluating Organochlorine and Organophosphate Pesticide Exposure in Children and Adolescents of Mexican Descent Residing in Hidalgo County, Texas.

Children and adolescents of Mexican descent residing in Hidalgo County (TX) were evaluated for exposure to organochlorine (OC) and organophosphate (OP) pesticides. A convenience sample of 60 participants enrolled in our pilot study. The lipid-adjusted serum concentrations of nine OC metabolites and creatinine-adjusted urinary concentrations of six OP metabolites were measured and compared with data from the Centers for Disease Control and Prevention's Fourth Report on Human Exposure to Environmental Chemicals. Descriptive statistics were used to summarize the concentration levels for each metabolite. Study participants were aged 5-18 years. For most of the OC and OP metabolites, our findings showed that participants had concentration levels within the distributional range of the national data. However, notable outlying levels (greater than the 95th percentile in the Fourth Report) were identified for the following OC metabolites: gamma-hexachlorocyclohexane, p,p'-dichlorodiphenyldichloroethene, and p,p'-dichlorodiphenyltrichloroethane. Among the children aged 5-11 years, one child had an outlying value for the OP metabolite: dimethylphosphate. Our findings on the levels of OC and OP pesticide exposure enhances the credibility of national estimates, and can serve as baselines for children and adolescents of Mexican descent residing in Lower Rio Grande Valley. Furthermore, our study contributes to the lacunae of knowledge regarding environmental exposures and presses further investigation of outlying OC and OP exposure levels.

A Study on the Knowledge, Perception, and Use of Breast Cancer Screening Methods and Quality of Care Among Women from Central Mexico.

Studies on health behaviors have observed several barriers to breast cancer screening, including lack of breast cancer knowledge, distrust of health care providers, and long waiting times to be screened or to receive screening results. We conducted a nested case-control study among a subsample of 200 women 21 years of age and older [100 patients (cases)], who had been diagnosed with breast cancer, and 100 controls, who were screened and found to be free of breast cancer), all residing in the Toluca metropolitan area in central Mexico. We examined how knowledge of breast cancer screening guidelines, perceptions of screening methods, and quality of health care influenced the use of breast cancer screening among study participants. Our study found that the most important factor associated with the decision to have breast cancer screenings was having a positive perception of the quality of care provided by the local health care centers, such as having competent clinic personnel, sufficient screening equipment, and reasonable waiting times to receive screening and to receive the screening results. Therefore, individual health care centers need to focus on the patients' perception of the services received by optimizing the care provided and, in so doing, increase the rates of early diagnosis and reduce the rate of mortality from breast cancer as well as its associated treatment costs.

Higher risk for obesity among Mexican-American and Mexican immigrant children and adolescents than among peers in Mexico.

We conducted a cross-sectional study among 1,717 children and adolescents of Mexican origin ages 5-19 years living in Mexico and Texas to explore the influence of country of birth and country of longest residence on their overweight and obesity status. Descriptive statistics were used to compare demographic and anthropometric characteristics of participants born and raised in Mexico (Mexicans), born in Mexico and raised in the United States (Mexican immigrants), and born and raised in the United States (Mexican-Americans). Univariate and multivariate nominal logistic regression was used to determine the demographic predictors of obesity adjusted by country of birth, country of residence, age, and gender. Almost half (48.8%) of the Mexican-Americans and 43.2% of the Mexican immigrants had body mass index at the 85th percentile or above, compared to only 29.3% of the Mexicans (P < .001). Thus, Mexican-Americans and Mexican immigrants were more likely to be obese than their Mexican peers [Mexican-Americans: odds ratio (OR) = 2.5 (95% confidence interval [CI] 1.8-3.4); Mexican immigrants: OR = 2.2 (95% CI 1.6-3.0)]. In addition, males were more likely than females to be obese [OR = 1.6 (95% CI 1.2-2.1)], and adolescents 15-19 years of age were less likely than their younger counterparts [OR = 0.5 (95% CI 0.4-0.7)] to be obese. The high prevalence of obesity among children of Mexican origin in the United States is of great concern and underscores the urgent need to develop and implement obesity preventive interventions targeting younger children of Mexican origin, especially newly arrived immigrant children. In addition, future obesity research should take into consideration the country of origin of the study population to develop more culturally specific obesity interventions.

Aplicabilidad del análisis por causa múltiple de muerte para el cáncer cervicouterino: la experiencia en México / Applicability of the analysis by multiple cause of death by cervical cancer: the experience in Mexico

Objecto. Explora-se a aplicabilidad da análise por causa múltipla de morte para o estudo do cancro cervicouterino. Métodos. Desenho de mortalidade proporcional para analisar todas as causas consignadas na totalidade dos certificados de morte por cancro cervicouterino de mulheres maiores de 18 anos do Estado de México (367), e 515 certificados de mulheres falecida por outras causas. Resultados. Encontrou-se uma razão de causa básica/múltipla de 2.9 nos certificados de morte, isto é pela cada causa básica encontraram-se 2.9 As mulheres falecidas por cancro cervicouterino morrem cinco anos dantes que as que morrem por outras causas (p<0.05). Ao ajustar as análise por causa múltipla para cancro cervicouterino por idade, escolaridad, estado civil, e direito habiencia, destaca a participação dos tumores malignos de lugares mau definidos como causas contribuintes e condicionantes [OR=14.24 (1.67-121.0) e OR=18.98 (2.28-157.56, respectivamente]; seguido pela diabetes mellitus também como contribuintes e sócias [OR=1.82 (1.02-3.27) e OR=7.78(1.46-41.37)] e a hipertensión arterial sistémica como causa sócia [OR = 3.0 (1.39-6.47)]. Conclusões. Causa múltipla é uma análise adequada para observar as doenças que intervêm, contribuem, condicionan e se associam ao cancro cervicouterino no momento da morte.

Objective. The study explores the applicability of the multiple-cause-of-death analysis for cervical-uterine cancer. Methods. A proportional mortality hazard design and the analysis of all causes of death due to cervical-uterine cancer from 367 death certificates of women older than 18 years of age from the State of Mexico, and 515 age and year adjusted sample of death certificates of women from the same region who died from other causes. Results. A basic multiple cause of death of 2.9 was observed in the death certificates, i.e., for every basic cause there were 2.9 multiple causes. When adjusting the multiple-causes-of-death analysis for cervical-uterine cancer by age, education, marital and insurability status, the most contributing and associated causes of death were malignant tumors from unspecified sites [OR=18.98 (2.28-157.56) and OR=14.25 (1.67-121.0)] respectively; Diabetes Mellitus as a contributing [OR=1.82 (1.02-3.27) and associated cause [OR=7.78 (1.46-41.37], and systemic arterial hypertension as an associated cause [OR=3.00 (1.40-6.47)]. Conclusions. The multiple-cause-of-death analysis is an adequate to observe the diseases that contribute condition and are associated to the cervical-uterine cancer.

[Applicability of the analysis by multiple cause of death by cervical cancer: the experience in Mexico]. / Aplicabilidad del análisis por causa múltiple de muerte para el cáncer cervicouterino: la experiencia en México.

Objective. The study explores the applicability of the multiple-cause-of-death analysis for cervical-uterine cancer. Methods. A proportional mortality hazard design and the analysis of all causes of death due to cervical-uterine cancer from 367 death certificates of women older than 18 years of age from the State of Mexico, and 515 age and year adjusted sample of death certificates of women from the same region who died from other causes. Results. A basic multiple cause of death of 2.9 was observed in the death certificates, i.e., for every basic cause there were 2.9 multiple causes. When adjusting the multiple-causes-of-death analysis for cervical-uterine cancer by age, education, marital and insurability status, the most contributing and associated causes of death were malignant tumors from unspecified sites [OR=18.98 (2.28-157.56) and OR=14.25 (1.67-121.0)] respectively; Diabetes Mellitus as a contributing [OR=1.82 (1.02-3.27) and associated cause [OR=7.78 (1.46-41.37], and systemic arterial hypertension as an associated cause [OR=3.00 (1.40-6.47)]. Conclusions. The multiple-cause-of-death analysis is an adequate to observe the diseases that contribute condition and are associated to the cervical-uterine cancer.

[Prenatal exposure to organochlorine pesticides and cryptorchidism]. / Exposición prenatal a los plaguicidas organoclorados y criptorquidia.

Fetuses and children are more susceptible to the effects of environmental toxins. The objective of this article is to determine the levels of organochlorine pesticides (HCB, ss-HCH, pp'DDT, op'DDT and pp'DDE) in the serum lipids of mothers of newborns with cryptorchidism and compare the levels to a control group of mothers of newborns with descended testicles. The cases were composed of newborns with cryptorchidism (n=41), and the controls (n=41) newborns with descended testicles. Blood samples from both groups of mothers were used to determine the organochlorine pesticide levels. Cryptorchidism was diagnosed at birth by a neonatologist. The results showed that the organochlorine pesticide residues were found in the serum lipids of both groups of mothers. The median serum lipid levels (mgkg-1 lipid-based) were statistically higher for the metabolites pp'DDT (0.464 vs. 0.269) and ss-HCH (0.263 vs. 0.192) in the cryptorchidism group compared to the control group (p<0.01). It could be concluded that the levels of the metabolites pp'DDT and ss-HCH are higher among mothers of newborns with cryptorchidism. It is possible that substances with anti-androgenic effects could produce endocrine disruption, such as cryptorchidism, during fetal development.

Exposición prenatal a los plaguicidas organoclorados y criptorquidia / Prenatal exposure to organochlorine pesticides and cryptorchidism

Los productos en desarrollo y los niños son particularmente vulnerables a los tóxicos ambientales. Nuestro objetivo es determinar los niveles de plaguicidas organoclorados (HCB, ß-HCH, pp'DDT, op'DDT y pp'DDE) en lípidos séricos de madres de niños con criptorquidia y comparar los niveles con un grupo control de madres de niños con testículos descendidos. El grupo de los casos fue constituido por recién nacidos con diagnóstico de criptorquidia (n=41). El grupo control (n=41) se conformó por niños con testículos descendidos. A las madres de ambos grupos se les determinaron los niveles de plaguicidas organoclorados. La criptorquidia fue diagnosticada al nacimiento por neonatólogo. Residuos de plaguicidas organoclorados fueron encontrados en lípidos séricos de ambos grupos. Los niveles de la mediana (mgkg-1 en base lipídica) fueron mayores para los metabolitos pp'DDT (0.464 vs. 0.269) y ß-HCH (0.263 vs. 0.192) en el grupo con criptorquidia comparado con el grupo control. (p<0.01). Los niveles de los metabolitos pp'DDT y ß-HCH son mayores entre las madres de los recién nacidos con criptorquidia. Es posible que sustancias con efectos antiandrogénicos puedan producir disrupción endocrina y criptorquidia durante el desarrollo fetal.

Fetuses and children are more susceptible to the effects of environmental toxins. The objective of this article is to determine the levels of organochlorine pesticides (HCB, ß-HCH, pp'DDT, op'DDT and pp'DDE) in the serum lipids of mothers of newborns with cryptorchidism and compare the levels to a control group of mothers of newborns with descended testicles. The cases were composed of newborns with cryptorchidism (n=41), and the controls (n=41) newborns with descended testicles. Blood samples from both groups of mothers were used to determine the organochlorine pesticide levels. Cryptorchidism was diagnosed at birth by a neonatologist. The results showed that the organochlorine pesticide residues were found in the serum lipids of both groups of mothers. The median serum lipid levels (mgkg-1 lipid-based) were statistically higher for the metabolites pp'DDT (0.464 vs. 0.269) and ß-HCH (0.263 vs. 0.192) in the cryptorchidism group compared to the control group (p<0.01). It could be concluded that the levels of the metabolites pp'DDT and ß-HCH are higher among mothers of newborns with cryptorchidism. It is possible that substances with anti-androgenic effects could produce endocrine disruption, such as cryptorchidism, during fetal development.

Maternal MTHFR polymorphisms and risk of spontaneous abortion / Polimorfismos maternos MTHFR y riesgo de aborto espontáneo

OBJECTIVE: To asses the association between intake of folate and B vitamins and the incidence of spontaneous abortion (SA) according to the maternal methylenetetrahydrofolate reductase (MTHFR) polymorphisms (677 C>T and 1298 A>C). MATERIAL AND METHODS: We conducted a nested case-control study within a perinatal cohort of women recruited in the state of Morelos, Mexico. Twenty-three women with SA were compared to 74 women whose pregnancy survived beyond week 20th. Intake of folate and B vitamins respectively, was estimated using a validated food frequency questionnaire. Maternal MTHFR polymorphisms were determined by PCR-RFLP and serum homocysteine levels by HPLC. RESULTS: Carriers of MTHFR 677TT and 1298AC genotypes respectively showed an increased risk of SA (OR 677TT vs. CC/CT=5.0; 95 percent CI: 1.2, 20.9 and OR 1298 AC vs. AA=5.5; 95 percent CI: 1.1, 26.6). CONCLUSIONS: Our results support the role of MTHFR polymorphisms as a risk factor for SA, regardless of dietary intake of B vitamins.

OBJETIVO: Evaluar la asociación entre aborto espontáneo (AE) y el consumo dietético de vitaminas B en mujeres mexicanas portadoras de los polimorfismos de la metilentetrahidrofolato reductasa (MTHFR) (677 C>T y 1298 A>C). MATERIAL Y MÉTODOS: Mediante un diseño de casos y controles anidados en una cohorte, se comparó la ingesta dietética materna de vitaminas B y folato, los polimorfismos maternos de la MTHFR y la concentración sérica de homocisteina de 23 casos de AE (< 20 semanas) y 74 controles (mujeres con embarazos > 20 semanas). RESULTADOS: Las portadoras de los genotipos MTHFR 677TT y 1298AC presentaron un incremento significativo en el riesgo de AE (RM 677TT vs. CC/CT=5.0; IC 95 por ciento: 1.2, 20.9 RM 1298 AC vs. AA=5.5; IC95 por ciento: 1.1, 26.6), respectivamente. CONCLUSIONES: Nuestros resultados apoyan el papel de la mutación de la MTHFR como posible factor de riesgo para el AE, independientemente del consumo de vitaminas B.

Maternal MTHFR polymorphisms and risk of spontaneous abortion.

OBJECTIVE: To asses the association between intake of folate and B vitamins and the incidence of spontaneous abortion (SA) according to the maternal methylenetetrahydrofolate reductase (MTHFR) polymorphisms (677 C>T and 1298 A>C). MATERIAL AND METHODS: We conducted a nested case-control study within a perinatal cohort of women recruited in the state of Morelos, Mexico. Twenty-three women with SA were compared to 74 women whose pregnancy survived beyond week 20th. Intake of folate and B vitamins respectively, was estimated using a validated food frequency questionnaire. Maternal MTHFR polymorphisms were determined by PCR-RFLP and serum homocysteine levels by HPLC. RESULTS: Carriers of MTHFR 677TT and 1298AC genotypes respectively showed an increased risk of SA (OR 677TT vs. CC/CT=5.0; 95% CI: 1.2, 20.9 and OR 1298 AC vs. AA=5.5; 95% CI: 1.1, 26.6). CONCLUSIONS: Our results support the role of MTHFR polymorphisms as a risk factor for SA, regardless of dietary intake of B vitamins.

Estimated risks of water and saliva contamination by phthalate diffusion from plasticized polyvinyl chloride.

Phthalates are additives commonly used to convert hard polyvinyl chloride (PVC) resins into flexible and workable plastics employed in the production of chewable rubber toys and other soft-plastic products. In theory, phthalates can diffuse in small quantities to the surface of a product, and from there they can enter the environment and the human body. The purpose of this study was to determine the diffusion of phthalates from plasticized PVC in water and artificial saliva; to determine the migration of di(2-ethylhexyl) (DEHP) phthalate in human saliva using gas chromatography; to compare the experimental values with theoretical values calculated using a model based on the principles of molecular diffusion in fluids; and to use the experimental values to estimate daily doses of DEHP received by Mexican children and infants using plastic and soft-plastic products (e.g., pacifiers, chewable toys, and bottles). Our findings indicated phthalate diffusion of 0.36 microg/cm2 per hour and 4.10 microg/cm2 per hour, respectively, in water and artificial saliva. The average value of phthalate diffusion in vivo was 6.04 microg/cm2 per hour. The daily oral phthalate exposure in Mexican infants and toddlers from oral use of rubber toys and soft-plastic products is 18.12 microg/kg. These daily doses are considerably lower than the maximum daily phthalate intake recommended by an international public health committee.

Maternal BMI and country of birth as indicators of childhood obesity in children of Mexican origin.

OBJECTIVE: The goal of this study was to evaluate the relationship between maternal and childhood BMI at baseline in a group of 5- to 18-year-old children and their mothers, all of whom were of Mexican origin, low socioeconomic status, and enrolled in a cohort study in Houston, TX. RESEARCH METHODS AND PROCEDURES: Using data from 438 mother-child dyads residing in the same household, we completed logistic regression analyses to determine maternal factors associated with the child being overweight or at-risk-for-overweight, after adjusting for the child's gender, age, and level of physical activity and other maternal confounders. RESULTS: Almost one-half of the boys and girls (47% and 44%, respectively) were either overweight or at-risk-for-overweight. Obese mothers were twice as likely to have an overweight and/or at-risk-for-overweight child compared with normal-weight mothers. Women born in the U.S. were twice as likely to have an overweight and/or at-risk-for-overweight child compared with women born in Mexico. In addition, women with less than a high school education were twice as likely to have an overweight child compared with their more educated peers. DISCUSSION: The high prevalence of overweight or at-risk-for-overweight among Mexican-origin children of low socioeconomic status suggests a continued need to develop and implement culturally sensitive preventive interventions for this minority population. Our data also suggest a need to tailor such interventions particularly for children of obese mothers and those born in the U.S.

Birthplace, years of residence in the United States, and obesity among Mexican-American adults.

OBJECTIVE: To evaluate the association between birthplace (Mexico or U.S.) and obesity in men and women and to analyze the relationship between duration of U.S. residency and prevalence of obesity in Mexican immigrants. RESEARCH METHODS AND PROCEDURES: We used cross-sectional data from 7503 adults of Mexican descent residing in Harris County, TX, to evaluate the relationships among BMI, birthplace, and years of residency in the U.S., controlling for demographic characteristics, physical activity level, and acculturation level. RESULTS: U.S.-born adults had an increased risk (between 34% and 65%) of obesity compared with their Mexican-born counterparts. After controlling for recognized confounders and risk factors, this association was maintained in the highly acculturated only. Among highly acculturated obese U.S.-born men, 6% of the cases were attributable to the joint effect of birthplace and acculturation; in women, this proportion was 25%. Among Mexican-born women, there was an increasing trend in mean BMI with increasing duration of residency in the U.S.. Compared with immigrants who had lived in the U.S. for <5 years, Mexican-born women who had resided in the U.S. for >or=15 years had an adjusted BMI mean difference of 2.12 kg/m2 (95% confidence interval, 1.53-2.72). DISCUSSION: Mexican-born men and women have a lower risk of obesity than their U.S.-born counterparts, but length of U.S. residency among immigrants, especially in women, is directly associated with risk of obesity. Development of culturally specific interventions to prevent obesity in recent immigrants may have an important public health effect in this population.

Self-Rated Health Among Adult Women of Mexican Origin.

Self-rated health (SRH), a consistent predictor of mortality among diverse populations, is sensitive to health indicators and social factors. American-born Hispanics report better SRH than their foreign-born counterparts but simultaneously report poorer health indicators and have shorter life expectancy. Using a matched prospective cross-sectional design, we analyzed data from 631 age-matched pairs of women, born in the United States or Mexico, enrolled in a cohort study based in Houston, Texas. Our first goal was to describe the relationships between SRH and health behaviors, physician-diagnosed chronic conditions, acculturation, and socioeconomic status (SES) by birthplace. Our second goal was to investigate the relative influence of SES, acculturation, health behaviors, and physician-diagnosed conditions in explaining expected differences in SRH between the two groups. Number of chronic conditions reported, particularly depression, more strongly influenced SRH than SES, acculturation, or reported health risk behaviors and the influence of birthplace is accounted for by these factors.