Health risk assessment in children living in an urban area with hydrofluorosis: San Luis Potosí Mexico case study.

BACKGROUND: Fluoride is an inorganic element, which can be found in high concentrations in groundwater. Its consumption and exposure have consequences on human health. The objective of this study was to evaluate fluoride exposure and develop a health risk assessment in children from an urban area with hydrofluorosis in Mexico. METHODS: Water fluoride levels in active wells were provided by the Water State Agency and divided into three zones: agriculture zone (Zone A), metallurgical zone (Zone B), and industrial zone (Zone C). Urinary fluoride levels were determined by potentiometric method using an ion-selective electrode. Health risk assessment was performed through Monte Carlo model analysis and hazard quotient was calculated. RESULTS: According to fluoride well concentration, all zones have high concentration especially Zone B (2.55 ± 0.98 mg/L). Urinary fluoride concentrations were highest in children in Zone B (1.42 ± 0.8 mg/L). The estimated median daily intake dose of fluoride was 0.084 mg/Kg-day for the children living in zone B. The highest mean HQ value was to Zone B (1.400 ± 0.980), followed by Zone C (0.626 ± 0.443). CONCLUSION: The levels of fluoride exposure registered are a potential risk to generate adverse health effects in children in the San Luis Potosi metropolitan area.

Application of Focused Ultrasound-Assisted Extraction for the Quantification of Persistent Organic Pollutions in Liver Tissue of Giant Toad (Rhinella marina).

A simple and rapid focused ultrasound extraction method was developed for the determination of Persistent Organic Pollutants (POPs) in liver tissue obtained of giant toad (Rhinella marina) using a gas chromatography coupled to a mass detector with electron impact ionization. The performed method for POPs, was validated in fortified matrix, showing linearity from the LOQ up to 100 ng/mL; LODs and LOQs for each compound were between 1.7 and 4.8 and 3.5-7.5 ng/mL, respectively. Recovery rates were among 79%-116% for POPs determined. Finally, the method was applied in liver samples of giant toads found in a malarial area in Mexico. The sensitivity of the proposed method was good enough to ensure reliable determination of target analytes at concentration levels commonly found in this kind of samples.

Assessment of exposure to mixture pollutants in Mexican indigenous children.

The aim of the present work was to complete an exposure assessment in three Mexican indigenous communities using the community-based health risk assessment, which is the first step in the CHILD framework. We used 1-hydroxypyrene (1-OHP) as an exposure biomarker to polycyclic aromatic hydrocarbons (PAHs) and trans, trans-muconic acid (t,t-MA) as an exposure biomarker to benzene, persistent organic pollutants (POPs), lead, manganese, arsenic, and fluoride. Anthropometric measurements were also taken. In these communities, high percentages of children with chronic malnutrition were found (28 to 49 %) based on their weight and age. All communities showed a high percentage of children with detectable levels of four or more compounds (70 to 82 %). Additionally, our results showed that in indigenous communities, children are exposed to elevated levels of certain environmental pollutants, including manganese with 17.6, 16.8, and 7.3 µg/L from SMP, TOC, and CUA, respectively. Lead and HCB levels were similar in the indigenous communities (2.5, 3.1, and 4.2 µg/dL and 2.5, 3.1, and 3.7 ng/mL, respectively). 1-OHP and t,t-MA levels were higher in TOC (0.8 µmol/mol of creatinine, 476 µg/g of creatinine, respectively) when compared with SMP (0.1 µmol/mol of creatinine, 215.5 µg/g of creatinine, respectively) and CUA (0.1 µmol/mol of creatinine, 185.2 µg/g of creatinine, respectively). DDE levels were 30.7, 26.9, and 9.6 ng/mL in CUA, SMP, and TOC, respectively. The strength of this study is that it assesses exposure to pollutants with indications for the resultant risk before an intervention is made by the CHILD program to manage this risk in the indigenous communities. Considering the large number of people, especially children, exposed to multiple pollutants, it is important to design effective intervention programs that reduce exposure and the resultant risk in the numerous indigenous communities in Mexico.

Analgesic activity of Heliopsis longipes and its effect on the nervous system.

Heliopsis longipes S.F. Blake (Asteraceae: Heliantheae) (chilcuague) is used in Mexican traditional medicine against parasites and to alleviate tooth and muscle pains. Its biocide effect has already been experimentally demonstrated; however, its analgesic action and its action on the nervous system (NS) have not been investigated yet. The objectives of this study were to evaluate the analgesic action of affinin and the H. longipes root ethanol extract, as well as their effects on the NS using an animal model. The ethanol extract was obtained by maceration, and affinin was purified from it through chromatographic techniques. Chemical and thermal analgesia were used to assess their analgesic proprieties. Irwin's test was used to evaluate their stimulating or depressing effects. The ethanol extract and affinin displayed analgesic action similar to ketorolac and stimulating effect comparable to caffeine on the nervous system of adult mice.

Antinociceptive, genotoxic and histopathological study of Heliopsis longipes S.F. Blake in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: H. longipes S.F. Blake (Asteraceae) is a Mexican plant, whose roots are traditionally used as a condiment, as a mouth anesthetic, and as an antiparasitic. Affinin is the alkamide present in higher amounts in the roots of H. longipes. AIM OF THE STUDY: To date, there are no published studies regarding the relation between the analgesic properties, in vivo cytotoxicity, and DNA-damaging potential of H. longipes ethanol extract (HLEE). MATERIALS AND METHODS: The HLEE was chromatographically fingerprinted to validate its affinin contents. Biological evaluation was conducted in sets of 6-8 CD1(+) mice. Antinociceptive effect was evaluated using the writhing and hot-plate tests, and mutagenic and cytotoxic effects were evaluated with micronucleous test in CD1(+) mice. For histopathological studies, biological samples from liver, heart, kidneys, spleen, lung, and brain were collected and stained. RESULTS: Oral administration of HLEE (3-100 mg/kg) produced a dose-dependent antinociceptive effect in both assays. In micronucleus assay, the variability in the number of micronucleated polychromatic erythrocytes (MNPE) induced, and PE/NE index, the ratio of polychromatic erythrocytes with respect to the number of normochromatic erythrocytes induced by HLEE in the evaluated schedule, were small and nonsignificant. After histopathological results, HLEE showed polioencephalomalacia with 1000 mg/kg dose. CONCLUSIONS: This work provides evidence that HLEE exerts analgesic effects, with no genotoxic effects in vivo. These findings would be an important contribution to explain the use of H. longipes root as an effective analgesic in traditional medicine, and to establish for the first time the absence of genotoxic and cytotoxic effects of the root in bioactive doses in vivo.

Interaction between Heliopsis longipes extract and diclofenac on the thermal hyperalgesia test.

Heliopsis longipes is an herbaceous plant found in Mexico, used traditionally for its analgesic and anesthetic activities. Plant extracts in combined use with synthetic drugs may represent a therapeutic advantage for the clinical treatment of pain, allowing the use of lower doses, and limiting side-effects. Therefore, the main objective of this study was to determine the possible pharmacological interaction between Heliopsis longipes ethanolic extract (HLEE) and diclofenac in the Hargreaves model of thermal hyperalgesia in the mouse. HLEE, diclofenac or fixed-dose ratio HLEE-diclofenac combinations were administered systemically to mice and the antihyperalgesic effect was evaluated using the thermal hyperalgesia test. All treatments produced a dose-dependent antihyperalgesic effect. ED(30) values were estimated for all the treatments and an isobologram was constructed. The derived theoretical ED(30) value for the HLEE-diclofenac combination was 54.4+/-9.4 mg/kg body wt, significantly higher than the actually observed experimental ED(30) value, 8.6+/-4.0 mg/kg body wt. This result corresponds to synergistic interaction between HLEE and diclofenac in the Hargreaves model of thermal hyperalgesia. Data suggest that low doses of the HLEE-diclofenac combination can interact synergistically at the systemic level and that this association may therefore represent a therapeutic advantage for the clinical treatment of inflammatory pain.