Sediment analysis and water quality assessment in the Pixquiac basin: drinking water supply of Xalapa city (Veracruz, Mexico).

Fluvial sediment analysis and water quality assessment are useful to identify anthropic and natural sources of pollution in rivers. Currently, there is a lack of information about water quality in the Pixquiac basin (Veracruz state, Mexico), and this scarcity of data prevents authorities to take adequate measures to protect water resources. The basin is a crucial territory for Xalapa, the capital city of Veracruz state, as it gets 39% of its drinkable water from it. This research analyzed 10 physicochemical parameters and 12 metal concentrations in various rivers and sources during two seasons. Dissolved metals presented average concentrations (µg/L): Al (456.25) > Fe (199.4) > Mn (16.86) > Ba (13.8) > Zn (7.6) > Cu (1.03) > Pb (0.27) > As (0.12) > Ni (0.118) (Cd, Cr and Hg undetectable). Metals in sediment recorded average concentrations (ppm): Fe (38575) > Al (38425) > Mn (460) > Ba (206.2) > Zn (65.1) > Cr (29.8) > Ni (20.9) > Cu (16.4) > Pb (4.8) > As (2.1) (Cd and Hg undetectable). During the rainy season, Water Quality Index (WAWQI) classified stations P17 and P18's water as "unsuitable for drinking" with values of 110.4 and 117.6. Enrichment factor (EF) recorded a "moderate enrichment" of Pb in sediment in P24. Pollution was mainly explained by wastewater discharges in rivers but also because of erosion and rainfall events. Statistical analysis presented strong relationships between trace and major metals which could explain a common natural origin for metals in water and sediment: rock lixiviation.

Identifying pollution dynamics using discrete Fourier transform: From an urban-rural river, Central Mexico.

The quality of life and human survival is dependent on sustainable development and sanitation of water bodies in an environment. The present research focuses on cyclicity data of more than 750,000 records of parameters associated with the water quality from a rural-urban river monitoring stations in real-time from River Atoyac in Central Mexico. The events detected in the instrumental records correlated with 2528 laboratory and instrumental determinations. The 64 polluting compounds were grouped into inorganic compounds (metals and metalloids) and organic compounds (pesticides, herbicides, hydrocarbons). Metal associated compounds were grouped along mechanical, pharmaceutical and textile industries which associates itself with the entry of polluting components. The cyclicity of the events was detected through Discrete Fourier Transformation time series analysis identifying the predominant events in each station. These highlight the events at 23-26 h corresponding to a circadian pattern of the metabolism of the city. Likewise, pollution signals were detected at 3.3, 5.5, and 12-14 h, associated with discharges from economic activities. Multivariate statistical techniques were used to identify the circadian extremes of a regionalized cycle of polluting compounds in each of the stations. The results of this research allow pollution prevention using a mathematical analysis of time series of different quality parameters collected at monitoring stations in real-time as a tool for predicting polluting events. The DFT analysis makes it possible to prevent polluting events in different bodies of water, allowing to support the development of public policies based on the supervision and control of pollution.

Impacts on water quality by in situ induced ozone­oxygen oxidation in a polluted urban reservoir.

The results of the successful implementation of a treatment based on the injection of ozone (O3) and oxygen (O2) into a contaminated body of water are reported for the first time. Three decontaminating units (SCAVENGER™), which have the capacity to inject up to 120 g O3/h and 250 Kg O2/h in the form of microbubbles (90 ± 10 µm in diameter), were placed in the contaminated Valsequillo reservoir, Central Mexico. In order to evaluate the efficacy of the treatment, 20 physicochemical parameters, 18 organic compounds, 66 inorganic compounds and 11 biological indicators were measured before, during and after the treatment; all of them in several representative sites of the east side of the Valsequillo reservoir. After 5 months of operating the SCAVENGER™ units in the eastern part of the reservoir, the concentration of Dissolved Oxygen (DO) increased 68%. Likewise, the chemical reducing conditions of the reservoir reflected by the low oxidation-reduction potential (ORP; -237 ± 75 mV) became quasi-oxidant (10 ± 58 mV). The treatment was efficient in water disinfection, presenting an 80% reduction in Fecal Coliforms (FC). Some heavy metals also showed a decrease in their concentration, being as follows: Al (65%), Cr (35%), Pb (46%), Zn (60%), Mn (20%), Mo (40%), Fe (32%), As (58%) and Co (26%). Due to the selective reactivity of ozone towards aliphatic and aromatic unsaturated compounds, several organic compounds reduced in their concentration by up to two orders of magnitude. Based on the above, it is evident that the treatment with ozone and oxygen was effective in substantially improving the quality of water in the east side of the Valsequillo reservoir.

Detection, provenance and associated environmental risks of water quality pollutants during anomaly events in River Atoyac, Central Mexico: A real-time monitoring approach.

River Atoyac is considered to be one of the most polluted rivers in Mexico due to the discharges of untreated or partially treated wastewater from industrial and municipal activities. In order to improve the river water quality, it is obligatory to identify the possible contaminant sources for upholding a well-balanced ecosystem. Henceforth, the present study incorporates the application of a continuous real-time monitoring system to identify the provenance of pollutants of the river mainly from anomaly events. Four monitoring stations were installed all along the River Atoyac in the State of Puebla, Central Mexico. The real-time monitoring systems have an ability to measure various water quality parameters for every 15 minutes such as Temperature (T), pH, Conductivity (EC), turbidity (TURB), Dissolved Oxygen (DO), Oxidation Reduction Potential (ORP) and Spectral Absorption Coefficient (SAC). In total, eight water samples of anomaly events (i.e.) 2 per monitoring station during rainy (August-September) and winter seasons (November-December), that were detected using the parameters previously mentioned were procured and also analyzed in the laboratory for evaluating almost 54 physicochemical, inorganic and organic characteristics. Statistical results of factorial analysis explained that 30% of the total variance corresponded to textile effluents, 23% related to discharges produced by automobile and petrochemical industries, and 18% of the total variance defined the agricultural activities. Additionally, indices like Overall Index Pollution, Heavy Metal Evaluation Index, Screening Quick Reference Table and Molecular ratios of hydrocarbons for PAH sources was also calculated to estimate the grade of pollution and associated ecotoxicological risks. The present study also enlightens the fact that the assessed results will definitely provide valuable information for the management of river water quality by developing stringent public policies by governmental agencies for the sustainable conservation of Atoyac River.

Repeated Pap smear screening among Mexican-American women.

The factors that influence repeated cervical cancer screening among Latina women are not well understood. Studies of compliance in this population over-emphasize initial or recent screening and under-emphasize how this practice is repeated over time. The purpose of this study was to identify the demographic and psychosocial factors associated with repeated Pap smear screening among low-income Mexican-American women living in two urban communities in Texas. A total of 1804 Mexican-American women were interviewed as part of a community survey. Multiple regression results indicate that demographic characteristics such as age, marital status, level of acculturation and health insurance were associated with the total number of Pap smears reported for the 5 years prior to the interview. Pap smear beliefs were the strongest predictor of repeated screening, while global beliefs about cancer did not significantly explain the results. Health promotion interventions should take into consideration the cultural and psychosocial needs of Mexican-American women, placing emphasis on their specific screening-related beliefs, if they are to succeed in promoting repeated compliance with Pap smear screening guidelines.

Social networks and cancer screening in four U.S. Hispanic groups.

BACKGROUND: Evidence shows that social relationships play an important role in health and health behavior. We examined the relationship between social networks and cancer screening among four U.S. Hispanic groups. METHODS: We used telephone surveys to collect data in eight U.S. regions that have concentrations of diverse Hispanic-origin populations. We interviewed 8903 Hispanic adults, for a response rate of 83%; analysis was restricted to the 2383 women aged > or =40. As a measure of social integration, we formed a social network index from items on the number of close relatives and friends, frequency of contact, and church membership. We used logistic regression to estimate the effects of social integration on screening, adjusting for sociodemographic factors. RESULTS: Among Mexican, Cuban, and Central-American women, the effect of social integration on mammography screening was slight. The odds ratios (OR) per unit change in social integration category ranged from 1.16 to 1.22 with confidence intervals (CI) that overlapped with the null. For Pap smear screening, the effect was strongest among Mexican-American women (OR=1.44, 95% CI=1.21 to 1.72), but also evident among Central-American women (OR=1.22, 95% CI=0.72 to 2.06) and Cuban women (OR = 1.25, 95% CI = 0.81 to 1.93). Among Puerto Rican women, social integration had no effect on either mammography (OR=1.03) or Pap smear screening (OR=1.08). CONCLUSIONS: Independent of socioeconomic factors, social integration appears to influence cancer screening participation of Hispanic women. The modest effect is not universal across Hispanic groups and was stronger for Pap smear than for mammography screening behavior. Researchers should recognize Hispanic group differences in social network characteristics and the potential of social networks to change screening behavior.

Family versus individually oriented intervention for weight loss in Mexican American women.

Mexican Americans are more likely to be obese than non-Hispanic whites, yet little research has been conducted on the treatment of obesity in Mexican Americans. The purpose of this study was to compare a family-based intervention with a traditional program oriented to the individual for achieving weight loss by obese Mexican American women. A total of 168 obese women were randomly assigned to one of three groups. Group 1 served as a comparison group and received only printed materials on nutrition, exercise, and behavioral principles for weight loss. Subjects in the individual group (group 2) received the same printed information, but they also attended classes led by bilingual registered dietitians. Subjects in the family group (group 3) received materials and attended classes that emphasized a family-oriented approach to making changes in eating habits and exercise behavior. Spouses and children attended classes with subjects in this group. Results revealed a significant linear trend in both body mass index and weight reduction across the groups, with losses greatest in the family group, followed by the individual group, and least in the comparison group. Both the individual and the family groups lost significantly more weight than the comparison group, although the difference between these two groups was not statistically significant. The results suggest that a culturally and linguistically appropriate program can achieve significant weight reduction among Mexican Americans. More research should be conducted on the effects of family and other types of social support on weight loss by Mexican Americans.

Smoking cessation in Texas-Mexico border communities: a quasi-experimental panel study.

UNLABELLED: BACKGROUDd. Smoking-related disease and injury is prominent among the numerous health problems on the U.S.-Mexico border, but little is known about the methods that might help promote smoking cessation among the low-income populations in this region. METHOD: Media campaigns were combined with different forms of intensive and community-wide interpersonal communication to encourage smoking cessation in a border U.S. city and in a Mexican city. Panels of moderate to heavy smokers were followed in four groups to allow quasi-experimental comparison of smoking cessation rates. RESULTS: Over a five-year study period smoking cessation rates of 17% (self-reported) and 8% (verified) were observed in panels in the program community (N = 160). In the comparison community (N = 135) corresponding rates of smoking cessation were 7% (self-reported) and 1.5% (verified). Within the program community, no differences were observed in smoking cessation among smokers exposed to a community-wide program and those assigned to receive personal counseling. DISCUSSION: Although the observed changes in smoking were unexpectedly small in the treatment and comparison groups, the approximately 8% effect size for the community-wide program was close to what was predicted. Results indicate that such programs may yield effects similar to those of more intensive approaches, but further research with greater statistical power will be necessary to confirm that point.

Cuidando El Corazon--a weight-reduction intervention for Mexican Americans.

Cuidando El Corazon (CEC; Taking Care of Your Heart) was designed to assess the effectiveness of a culturally adapted weight-reduction and exercise program for achieving long-term weight loss in Mexican Americans. CEC used a family-oriented approach to achieve lifestyle change in behavior. Participants were assigned to 1) a booklet-only comparison group that received a manual including behavior change, nutrition, and exercise information and traditional recipes modified in fat content; 2) an individual group that received the same manual and attended year-long classes; or 3) a family group that received a manual and attended classes that emphasized techniques for making changes in the family's eating and exercising habits. The family and individual groups had significantly greater weight losses than the information-only group. Weight loss was greatest in the family-involvement group and least in the information-only comparison group.

Communicating health information to urban Mexican Americans: sources of health information.

Data from a six-week hypertension campaign aimed at urban Mexican Americans were analyzed to document how they receive their health information and to identify the communication channels most likely to reach different segments of the Mexican-American community. The nine sources of information examined were doctor, nurse, pharmacist, family, friends, radio, newspaper, television, and magazine. The most common source of health information reported was doctor, followed by television, newspapers, magazines, family, and radio. Interview language (Spanish or English) was a significant predictor of the amount of health information received from all nine sources. Sex, family income, education, and age also were shown to affect the amount of health information received from various sources. Profiles of respondents most likely to use each source of health information are presented and implications for health educators are discussed.

El asesino silencioso: a methodology for alerting the Spanish-speaking community.

Information describing the health status of the Spanish-speaking population, the nation's second largest minority, is extremely scarce. In particular, few studies have attempted to document the prevalence or ascertain the extent of treatment or the level of public awareness of hypertension or other cardiovascular diseases in this minority population. However, before any large scale effort to determine the prevalence or to determine the treatment and awareness needs related to hypertension is initiated, preliminary questions concerning how to reach and motivate the Spanish-speaking population to adopt cardiovascular health risk-reducing behaviors must be answered.