Pilot Monitoring of Lead in Umbilical Cord Blood of Newborns Associated With the Use of Glazed Ceramics from Guanajuato, Mexico.

The use of lead-glazed pottery for cooking and storing food, a widespread practice in Mexico, represents a risk of exposure to lead from the human intrauterine stage. Therefore, a pilot study was carried out by means of the measurement of lead in umbilical cord blood by inductively coupled plasma mass spectrometry (ICP-MS) including 69 newborns from the Mexican state capital of Guanajuato, Guanajuato City, where the use of glazed clay is still widespread. Lifestyle and sociodemographic data were collected by interviewing the participating mothers. Hematological parameters and the anthropometry of the newborns and their mothers were analyzed; likewise, the G177C polymorphism in the ALAD gene was genotyped by PCR-RFLP as a marker of genetic vulnerability to lead. The geometric mean of lead in umbilical cord blood was 0.7 µg/dL (< limit of detection = 0.01-28.22). Boys presented higher values than girls (p = 0.03). Only 5.8% of these were above the safety value of the US Centers for Disease Control and Prevention (CDC) of 3.5 µg/dL. Correlations among lead concentrations, maternal age, weeks of gestation, newborn anthropometry, and hematological parameters were not found; however, the participating mothers who reported using glazed ceramics for cooking or storing food had the highest cord-blood lead concentrations (p = 0.04). Regarding genotyping, 97% had ALAD 1, while 3% had ALAD 1, 2; unfortunately, the sample size did not allow analysis of genetic vulnerability to lead. The preparation and conservation of food in handcrafted clay pottery increased the risk of having cord-blood lead values higher than those recommended by the CDC of 3.5 µg/dL (OR = 5; 95% CI:1.3-23; p = 0.01). Our preliminary results suggest that there continues to be intrauterine exposure to lead in Guanajuato.

Health Risk Assessment in Mexican Children Exposed to Fluoride from Sweetened Beverages.

The primary source of fluoride exposure is groundwater, but evidence suggests that beverages and food are additional fluoride sources. Intake of these products at an early age affects the optimal functioning of soft organs. An increase in sweetened beverage consumption by the pediatric population has been reported, suggesting an increase in fluoride exposure. The objectives of this study were to determine the fluoride concentrations in beverages and analyze the risk to human health from fluoride exposure to sweetened beverages consumed by children. Eighty-two sugar-sweetened beverages produced in different Mexican states were analyzed. The fluoride determination was carried out with an ion-selective electrode. The highest fluoride concentration was 1.92 mg/L; 73.2% of beverages showed fluoride values above permitted limits. Low-cost beverages had the highest fluoride values, suggesting that the water used for their production does not comply with fluorine regulations. According to the risk assessment in children from 3 to 6 years, the daily consumption of juices and sodas with concentrations that exceeded the normative of 0.7 mg/L could represent a risk to dental fluorosis development. It is crucial to control fluoride and regulate its concentrations in beverages for children to ensure food safety, especially in areas of endemic hydrofluorosis.

Environmental and biological monitoring of organochlorine pesticides in the city of Salamanca, Mexico.

The former Tekchem Industrial Unit located in the city of Salamanca, Mexico, constitutes an environmental liability in which the presence of high levels of organochlorine pesticides (OCPs) has been reported. In the present study, levels of OCPs were quantified using gas chromatography-mass spectrometry in 52 soil samples and in 88 blood samples from school-age children in the city of Salamanca. A median concentration of 70.6 ng/g (6.93-3299) was obtained for total OCPs in soil, while for the total sum of dichlorodiphenyltrichloroethane (DDT) the value was 49.6 ng/g (6.93-3276). In children, the median level of the total sum of OCPs was 390 ng/g lipid (7.34-14,895), and for the total sum of DDT was 175 ng/g lipid (< LOD-14,802). The OCPs that resulted in highest concentrations in soil were DDT and its metabolites, as well as aldrin and heptachlor epoxide, while in blood the highest levels corresponded to 4,4'-dichlorodiphenyltrichloroethane (4,4'-DDT) and its metabolites, followed by heptachlor and heptachlor epoxide. The spatial distribution of the concentrations of OCPs in soil shows that the facilities of Tekchem may be a significant potential source for the dispersion of these compounds toward the metropolitan area of Salamanca. The results obtained in the present study demonstrate the presence of OCPs in soil and in child population, providing important bases to study the problem from a broader perspective, while reiterating the importance of continuing efforts to generate resolute and precautionary measures with respect to the environmental liability of Tekchem.

Fluoride Concentration in Urine after Supplementation with Quelites in a Population of Adolescents.

Wild plants have detoxifying and protective properties. They reduce or neutralize the toxic effects caused by chemical agents and pollutants and have beneficial effects on the nutritional and health status. This research was conducted to complement a previous clinical intervention in which participants were exposed to high concentrations of arsenic and fluoride in drinking water to discover similarities or differences in the pattern of fluoride (F-) excretion after supplementation with partial areas of purslane and quelite cenizo (SP-Q). The study was 4 weeks long, and it was carried out on a sample of 27 adolescents in an age range of 11-12 years. Anthropometric and dietary evaluations were performed, and the concentrations of fluoride (F-) in urine and drinking water were quantified using the potentiometric method with an ion-selective electrode. The treated group increased urinary F- excretion after the first week (Baseline: 9.23 mg/g creatinine; Week 2: 0.73 mg/g creatinine), together with significant mobilization of F- and a recovery process at the end of the intervention (Week 4: 0.52 mg/g creatinine). The supplement may act by increasing the excretion of F- and the nutritional dietary conditions that contribute to mitigation and recovery in participants exposed to the contaminant while also managing access to drinking water.

Fluoride Exposure through Different Drinking Water Sources in a Contaminated Basin in Guanajuato, Mexico: A Deterministic Human Health Risk Assessment.

Water fluoride levels above the World Health Organization's guideline (1.5 mg/L), common in overexploited aquifers, represent a health hazard. Our objective was to assess the health risks posed by exposure to fluoride in different drinking water sources in a contaminated basin in Mexico. Fluoride was measured in mutual drinking water sources and in the urine of 39 children and women. Risks were estimated through hazard quotient (HQ) by drinking water source. Dental fluorosis was assessed in the children. Mean fluoride water concentrations (mg/L) were: well, 4.2; waterhole, 2.7; bottled, 2.1; rainwater, 0.4. The mean urinary fluoride concentrations (specific gravity adjusted) were 2.1 mg/L and 3.2 mg/L in children and women, respectively. Our multiple linear regression model showed children's urinary fluoride concentrations increased 0.96 mg/L for every 1 mg/L increase in water fluoride (p < 0.001). Dental fluorosis was diagnosed in 82% of the children, and their HQ according to drinking water source was: well, 1.5; waterhole, 1.1; bottled, 0.8; harvested rainwater, 0.3. The pervasive dental fluorosis indicates a toxic past fluoride exposure; urinary fluoride levels and HQs indicate high exposure and current health risks for most children. Drinking harvested rainwater will likely prevent most of the local fluoride exposure.

Exposure to arsenic and lead in children from Salamanca México, effects on telomeric lengthening and mitochondrial DNA.

Levels of urinary arsenic and levels of lead in blood were measured in children attending elementary schools located in an industrial zone in Salamanca, México. Its possible effects using telomere length and mitochondrial DNA copy number as biomarkers of genomic disequilibrium by oxidative stress were studied. Eighty-eight children (6-15 years old) were included and urine samples were collected for quantification of arsenic, while lead was measured in blood samples using inductively coupled plasma mass spectrometry (ICP-MS). DNA was isolated from peripheral blood and relative telomere length and the mitochondrial DNA copy number were determined by real-time PCR. The geometric mean of urinary arsenic was 54.16 µg/L (11.7-141.1 µg/L). Ninety-eight percent of the children were above 15 µg/L (biomonitoring equivalent value). With respect to the concentration of lead in blood, the mean was 3.78 µg/dL (LOD-22.61), where 24.5% of the participants had equal or above the reference value (5 µg/dL; Mexican Official Norm NOM-199-SSA1-2000, 2017). A positive association between urinary arsenic and telomere length was found (ß = 0.161; 95% CI: 0.12; 0.301; P = 0.034), while lead blood concentrations were negatively associated with mitochondrial DNA copy number (ß = - 0.198; 95% CI: - 2.81; - 0.17; P = 0.019), after adjusting by age, sex, and total white blood cell count. Differences in the mitochondrial DNA content were observed in children with lead blood levels from 2.5 µg/dL, (P ≤ 0.001), suggesting an effect at lead exposure levels considered acceptable (< 5 µg/dL). In conclusion, children living in an industrial area in Salamanca showed an exposure to arsenic and lead and an impact on telomere length and mitochondrial DNA content associated with arsenic and lead exposure, respectively.

Dosis de exposición a fluoruros por el consumo de diferentes tipos de leche en residentes de una zona con hidrofluorosis endémica en México / Level of exposure to fluorides by the consumption of different types of milk in residents from an area of Mexico with endemic hydrofluorosis

Introducción: Diversos estudios han demostrado la presencia de fluorosis (FD) en la dentición primaria, lo que puede indicar una exposición a los fluoruros (F-) en la primera infancia. La leche materna se recomienda como alimento exclusivo hasta los 6 meses de edad. Aunque se menciona que solo una pequeña cantidad de F- puede eliminarse por leche materna, estudios han demostrado la presencia de este elemento en leche de mujeres residentes de zonas contaminadas, así como en leche de fórmulas comerciales. El objetivo del proyecto fue evaluar la dosis de exposición a F- a través de leche en niños residentes de una zona con hidrofluorosis endémica. Metodología: Un total de 110 niños de entre 6 y 36 meses de edad del municipio de Lagos de Moreno, Jalisco, México, participaron en el estudio. Se colectaron muestras de agua de los hogares, leche y orina. Las muestras se cuantificaron con el electrodo de ion selectivo. Se calculó la dosis de exposición a F- a través del programa Oracle Crystal Ball. Resultados: Se observaron dosis superiores a la dosis de referencia para FD en la leche de fórmula reconstituida con agua de abastecimiento público, de vaca pasteurizada (entera) y de vaca sin tratamiento sanitario (cruda) en el percentil 90, 70 y 50, respectivamente, así como una correlación entre los niveles de F- en leche y F- en orina (r = 0,41; p < 0,001). Conclusiones: La identificación de fuentes de F- en etapas tempranas del desarrollo infantil podría reducir el riesgo de presentar FD

Introduction: Several studies have shown the presence of fluorosis (DF) in primary dentition, suggesting an exposure to fluorides (F-) in early childhood. Breast milk is recommended as an exclusive food until 6 months of age. Although it is mentioned that only a small amount of F- can be eliminated by breast milk, studies have shown the presence of this element in milk of women living in contaminated areas, as well as in infant formulas. The objective of this project was to evaluate the exposure level to F- through milk in children living in an area with endemic hydrofluorosis. Methodology: The study included 110 children between 6 and 36 months of age from the municipality of Lagos de Moreno, Jalisco. Water samples were collected from the homes, as well as samples of milk (maternal, formula, whole or raw), and urine. Measurments were made with a selective ion electrode. The exposure level of F- for milk intake was calculated using the Oracle Crystal Ball package. Results: Levels greater than the reference level for DF were observed in infant formula reconstituted with public supply water, pasteurised cow's milk (whole) and untreated cow's milk treatment (raw) in the 90th, 70th, and 50th percentile, respectively, with a correlation being found between the levels of F- in milk and F- in urine (r = 0.41, P < .001)

[Level of exposure to fluorides by the consumption of different types of milk in residents from an area of Mexico with endemic hydrofluorosis]. / Dosis de exposición a fluoruros por el consumo de diferentes tipos de leche en residentes de una zona con hidrofluorosis endémica en México.

INTRODUCTION: Several studies have shown the presence of fluorosis (DF) in primary dentition, suggesting an exposure to fluorides (F-) in early childhood. Breast milk is recommended as an exclusive food until 6 months of age. Although it is mentioned that only a small amount of F- can be eliminated by breast milk, studies have shown the presence of this element in milk of women living in contaminated areas, as well as in infant formulas. The objective of this project was to evaluate the exposure level to F- through milk in children living in an area with endemic hydrofluorosis. METHODOLOGY: The study included 110 children between 6 and 36 months of age from the municipality of Lagos de Moreno, Jalisco. Water samples were collected from the homes, as well as samples of milk (maternal, formula, whole or raw), and urine. Measurments were made with a selective ion electrode. The exposure level of F- for milk intake was calculated using the Oracle Crystal Ball package. RESULTS: Levels greater than the reference level for DF were observed in infant formula reconstituted with public supply water, pasteurised cow's milk (whole) and untreated cow's milk treatment (raw) in the 90th, 70th, and 50th percentile, respectively, with a correlation being found between the levels of F- in milk and F- in urine (r=0.41, P<.001). CONCLUSIONS: The identification of sources of F- in the early stages of child development could reduce the risk of developing DF.

Effect of a Supplementation with Two Quelites on Urinary Excretion of Arsenic in Adolescents Exposed to Water Contaminated with the Metalloid in a Community in the State of Guanajuato, Mexico.

Quelites are Mexican wild plants, reported as excellent sources of nutritional compounds such as amino acids (serine, glycine, and cysteine), minerals (Mg, Fe, and Zn), and phytochemicals, as phenolic acids (chlorogenic acid) and flavonoids (phloridzin and naringenin); on the other hand, high biological activity has been shown in these compounds. This work aimed to evaluate the effect of a supplementation with two endemic quelites of Mexico (Chenopodium berlandieri L. and Portulaca Oleracea L.); in addition to supplementation, a nutritional intervention was performed; the biomarkers of hemoglobin (Hb), urinary malondialdehyde (UMDA), and urinary arsenic (UAs) were measured in adolescents exposed to arsenic. A clinical intervention study was conducted in 27 adolescents ages 11 to 12 years for 4 weeks. Weekly anthropometric and dietary evaluations were carried out, as well as the concentration of Hb; the UMDA and UAs were performed by plate-based colorimetric measurement and atomic absorption spectrophotometry with the hydrides generation system, respectively. The results showed that UMDA concentrations had a significant improvement in the supplemented group (SG) vs. control group (CG) (SG = 1.59 ± 0.89 µM/g creatinine vs. CG = 2.90 ± 0.56 µM/g creatinine) in the second week of intervention; on the other hand, the supplemented group showed an increase in Hb levels (15.12 ± 0.99 g/dL) in the same week; finally after the second week, an increase in UAs levels was observed significantly compared to the baseline value (Baseline: 56.85; Week 2: 2.02 µg/g creatinine). Therefore, the results show that the mixture of quelites (a rich source of phytochemicals and nutrients) improved hemoglobin and UMDA levels, and urinary arsenic excretion from the second week in the exposed population.

Association of Leukocyte Telomere Length and Mitochondrial DNA Copy Number in Children from Salamanca, Mexico.

AIM: The purpose of this study was to determine if there is a correlation between telomere length (TL) and mitochondrial DNA copy number (mtDNAcn) in children. METHODS: Leukocyte TL and mtDNAcn were measured by real-time PCR in 98 Mexican children 6-12 years of age from Salamanca, México. RESULTS: A positive association was found between TL and mtDNAcn after a natural log transformation (Pearson correlation r = 0.72; p < 0.0001). No correlation between age and body mass index (BMI) biomarkers was found, and no differences according to sex were observed. After adjustment for these variables, a linear regression model showed an association between TL and mtDNAcn (ß = 0.739, 95% confidence interval 0.594; 0.885, p < 0.0001). CONCLUSIONS: A strong positive correlation between TL and mtDNAcn was found in the study population; age, sex, and BMI seemed to have no effect on this correlation.

Association between urine fluoride and dental fluorosis as a toxicity factor in a rural community in the state of San Luis Potosi.

OBJECTIVE: The aim of this study is to investigate urine fluoride concentration as a toxicity factor in a rural community in the state of San Luis Potosi, Mexico. MATERIALS AND METHODS: A sample of 111 children exposed to high concentrations of fluoride in drinking water (4.13 mg/L) was evaluated. Fluoride exposure was determined by measuring urine fluoride concentration using the potentiometric method with an ion selective electrode. The diagnosis of dental fluorosis was performed by clinical examination, and the severity of damage was determined using Dean's index and the Thylstrup-Fejerskov (TF) index. RESULTS: The range of exposure in the study population, evaluated through the fluoride content in urine, was 1.1 to 5.9 mg/L, with a mean of 3.14±1.09 mg/L. Dental fluorosis was present in all subjects, of which 95% had severe cases. Higher urine fluoride levels and greater degrees of severity occurred in older children. CONCLUSIONS: The results show that dental fluorosis was determined by the presence of fluoride exposure finding a high positive correlation between the severity of fluorosis and urine fluoride concentration and the years of exposure suggested a cumulative effect.

Parameters of lung inflammation in asthmatic as compared to healthy children in a contaminated city.

BACKGROUND: The impact of air pollution on the respiratory system has been estimated on the basis of respiratory symptoms and lung function. However; few studies have compared lung inflammation in healthy and asthmatics children exposed to high levels of air pollution. The aim of the study was to elucidate the modulatory effect of air pollution on Cysteinyl-leukotrienes (Cys-LTs) levels in exhaled breath condensate (EBC) among healthy and asthmatic children. METHODS: We performed a cross-sectional comparative study. Children between 7-12 years of age, asthmatics and non-asthmatics, residents of a city with high levels of PM10 were included. In all cases, forced spirometry, Cys-LTs levels in EBC, and the International Study of Asthma and Allergies in Childhood questionnaire were evaluated. We also obtained average of PM10, CO, SO2 and O3 levels during the period of the study by the State Institute of Ecology. RESULTS: We studied 103 children (51 asthmatics and 52 non-asthmatics). Cys-LTs levels were higher in asthmatics than in non-asthmatics (77.3 ± 21.6 versus 60.3 ± 26.8 pg/ml; p = 0.0005). Also, Cys-LTs levels in children with intermittent asthma were lower than in children with persistent asthma (60.4 ± 20.4 versus 84.7 ± 19.2 pg/ml; p = 0.0001). In the multiple regression model, factors associated with levels of Cys-LTs were passive smoking (ß = 13.1, p 0.04) and to be asthmatic (ß = 11.5, p 0.03). CONCLUSIONS: Cys-LTs levels are higher in asthmatic children than in healthy children in a contaminated city and its levels are also associated with passive smoking.

Apoptosis of peripheral blood mononuclear cells in children exposed to arsenic and fluoride.

In this study, we evaluated apoptosis induction in human immune cells in children exposed to arsenic (As) and fluoride (F). Children living in two areas in Mexico (Soledad de Graciano Sanchez (SGS) in San Luis Potosí and Colonia 5 de Febrero in Durango) were studied. Water, urine and blood samples were collected. Approximately 90% of the water samples in 5 de Febrero had As and F levels above the World Health Organization intervention guideline (10 µg/L and 1.5mg/L, respectively). In SGS, 0% of the water samples exceeded Mexican guidelines. Urinary As and F levels in children living in 5 de Febrero were significantly higher than the levels found in children living in SGS. In addition, the level of apoptosis was higher in children from the 5 de Febrero community when compared with the level of apoptosis in children living in SGS. Thus, in a worldwide context, our study demonstrates the health risks to children living in these regions.

Assessment of polychlorinated biphenyls and mercury levels in soil and biological samples from San Felipe, Nuevo Mercurio, Zacatecas, Mexico.

The aim of this work was to evaluate contamination by polychlorinated biphenyls and mercury in soil, and to assess exposure level to both contaminants in children living in San Felipe, Nuevo Mercurio, Zacatecas, Mexico. We found soil levels of total polychlorinated biphenyls ranging from non detectable (nd) to 190 µg/kg. Mercury soil levels ranged from 8.9 to 10215.0 mg/kg. Exposure levels of total polychlorinated biphenyls assessed in blood and urinary mercury in children living in the studied community were 1,600 ± 8,800 ng/g lipid and 4.2 ± 7.1 µg/g creatinine, respectively.

Decreased intelligence in children and exposure to fluoride and arsenic in drinking water.

Recent evidence suggests that fluoride (F) and arsenic (As) may adversely affect intelligence quotient (IQ) scores. We explore the association between exposure to F and As in drinking water and intelligence in children. Three rural communities in Mexico with contrasting levels of F and As in drinking water were studied: Moctezuma (F 0.8+/-1.4 mg/L; As 5.8+/-1.3 microg/L); Salitral (F 5.3+/-0.9 mg/L; As 169+/-0.9 microg/L) and 5 de Febrero (F 9.4+/-0.9 mg/L; As 194+/-1.3 microg/L). The final study sample consisted of 132 children from 6 to 10 years old. After controlling for confounders, an inverse association was observed between F in urine and Performance, Verbal, and Full IQ scores (beta values = -13, -15.6, -16.9, respectively). Similar results were observed for F in drinking water (beta values = -6.7, -11.2, -10.2, respectively) and As in drinking water (beta values= -4.30, -6.40, -6.15, respectively). The p-values for all cases were < 0.001. A significant association was observed between As in urine and Full IQ scores (beta = -5.72, p = 0.003). These data suggest that children exposed to either F or As have increased risks of reduced IQ scores.

Decreased intelligence in children and exposure to fluoride and arsenic in drinking water

Recent evidence suggests that fluoride (F) and arsenic (As) may adversely affect intelligence quotient (IQ) scores. We explore the association between exposure to F and As in drinking water and intelligence in children. Three rural communities in Mexico with contrasting levels of F and As in drinking water were studied: Moctezuma (F 0.8±1.4mg/L; As 5.8±1.3µg/L); Salitral (F 5.3±0.9mg/L; As 169±0.9µg/L) and 5 de Febrero (F 9.4±0.9mg/L; As 194±1.3µg/L). The final study sample consisted of 132 children from 6 to 10 years old. After controlling for confounders, an inverse association was observed between F in urine and Performance, Verbal, and Full IQ scores (beta values = -13, -15.6, -16.9, respectively). Similar results were observed for F in drinking water (beta values = -6.7, -11.2, -10.2, respectively) and As in drinking water (beta values= -4.30, -6.40, -6.15, respectively). The p-values for all cases were < 0.001. A significant association was observed between As in urine and Full IQ scores (beta = -5.72, p = 0.003). These data suggest that children exposed to either F or As have increased risks of reduced IQ scores.

Estudios recientes sugieren que el flúor (F) y el arsénico (As) pueden tener efectos adversos sobre el coeficiente intelectual (CI). En este estudio exploramos la asociación entre el F y el As y la inteligencia en niños expuestos a estas sustancias a través del agua. Tres comunidades rurales de México con diferentes niveles de F y As fueron estudiadas: Moctezuma (F 0,8±1,4mg/L; As 5,8±1,3µg/L); Salitral (F 5,3±0,9mg/L; As 169±0,9µg/L) y 5 de Febrero (F 9,4±0,9mg/L; As 194±1,3µg/L). La muestra final fue de 132 niños de 6 a 10 años de edad. Después de controlar por confusores, se obtuvieron asociaciones inversas entre F en orina y las puntuaciones de los CI (Desempeño, Verbal y Total) (valores beta = -13, -15,6, -16,9, respectivamente) p < 0,001 en todos los casos. Resultados similares se obtuvieron con F en agua (valores beta = -6,7, -11,2, -10,2, respectivamente) y con As en agua (valores beta = -4,30, -6,40, -6,15, respectivamente). En todos los casos p < 0,001. Para As en orina, se obtuvo una asociación inversa con las puntuaciones del CI total (beta= -5,72; p = 0,003). Estos datos sugieren que los niños expuestos al F o al As tienen mayor riesgo de tener disminución en las puntuaciones del CI.