Attitudes and beliefs about environmental hazards in three diverse communities in Texas on the border with Mexico.

OBJECTIVE: Since communicating risk related to environmental hazards has consistently presented a challenge to government agencies and industries, our objective was to better understand the attitudes and beliefs of three communities, so as to help agencies and industries develop better risk communication interventions. METHODS: We explored attitudes and beliefs about environmental risks in three diverse communities in Texas on the border with Mexico, in the county of El Paso. During the summer of 1995, using a door-to-door survey, we interviewed 147 individuals, using a questionnaire based upon an existing instrument. Interviews were conducted in three very different areas of the county: semirural low-income, urban low-income, and suburban upper-income. We randomly selected specific sections in each of the three communities for inclusion in the sample. We assessed attitudes and beliefs about regulations and experts, risk and hazards, and how to address environmental issues. RESULTS: Attitudes and beliefs varied among the three communities, especially in the assessment of riskiness of various hazards. In general, there was mistrust of government agencies and of industries, a strong feeling that the environment can be improved, and a lack of understanding about what actions individuals might take to improve the environment. DISCUSSION: Agencies need to find ways to increase their credibility with the public, and they should assess communities in order to understand the attitudes of the residents.

Job satisfaction among nursing staff in a military health care facility.

Job satisfaction in the workplace affects absenteeism, turnover, and performance. We conducted a cross-sectional study of 201 nursing personnel to assess satisfaction among nursing staff at a military hospital in the southwestern United States. Participants completed a self-administered survey in which they rated professional status, autonomy, pay, organizational policies, task requirements, and interaction by importance and satisfaction. Autonomy, professional status, and pay were the most important factors and organizational policies was the least important factor. Military staff were slightly more satisfied with staff interactions than civilian staff. Nursing personnel working in specialty care units were significantly more satisfied with interactions and professional status, but they valued organizational policies less than those working in general units. Professionals were significantly more satisfied with pay and autonomy, whereas nonprofessionals were more satisfied with task requirements and professional status.

Effects of temperature and snowfall on mortality in Pennsylvania.

The relation between exposure to severe cold weather and mortality is examined in a retrospective study of deaths occurring during the month of January from 1991 to 1996 in Pennsylvania. Using division-days as units of observation (n = 1,560) aggregated from death certificates and geographic divisions, the authors estimated mortality rates for total deaths and deaths due to ischemic heart disease, cerebrovascular diseases, and respiratory diseases by analyses based on generalized estimating equations. Total mortality increased on days of "extreme" climatic conditions, that is, when snowfall was greater than 3 cm and when temperatures were below -7 degrees C (rate ratio (RR) = 1.27, 95 percent confidence interval (CI) 1.12-1.44). On days of extreme conditions, mortality due to ischemic heart diseases tripled among males aged 35-49 years (RR = 3.54, 95 percent CI 2.35-5.35), increased for men aged 50-64 years (RR = 1.77, 95 percent CI 1.32-2.38), and rose for males aged 65 years and older (RR = 1.58, 95 percent CI 1.37-1.82), when compared with milder conditions. Among females, mortality for those aged 65 years and older increased for respiratory causes (RR = 1.68, 95 percent CI 1.28-2.21) and cerebrovascular causes (RR = 1.47, 95 percent CI 1.13-1.91). Cold and snow exposure may be hazardous among men as young as 35 years.

Determination of niacin in infant formula and wheat flour by anion-exchange liquid chromatography with solid-phase extraction cleanup.

Niacin content must be included on food labels of infant formula products and bakery products containing enriched flour. Liquid chromatographic (LC) determination of niacin in complex food matrixes is complicated by the presence of endogenous compounds that absorb at the commonly used wave-length of 260 nm. Also, the presence of particulate matter in the standard sulfuric acid extraction procedure results in reduced life of LC columns and precolumns. A simple, rapid, solid-phase extraction (SPE) procedure for separation and cleanup of niacin from a complex food matrix digest has been developed. By using a vacuum manifold with the SPE column system, multiple samples can be processed quickly and efficiently for LC analysis, compared with gravimetric column cleanup. Sulfuric acid sample digest is passed over an aromatic sulfonic acid cation-exchange (ArSCX-SPE) or a sulfonated Florisil SPE column. Niacin is eluted with 0.25M sodium acetate-acetic acid, pH 5.6 buffer in vacuo. LC chromatograms of the resulting eluate are free of interference from other components absorbing at 260 nm at the retention time of niacin. Validation of the method was obtained from agreement of analytical results on available reference materials. For both SPE methods, values for niacin in SRM 1846 Infant Formula (milk-based powder) were within uncertainty ranges of the certified value. Use of several calibration procedures (the LC computer program, a peak area response graphic standard curve, or the method of standard additions) with both SPE procedures resulted in niacin values for 3 RM-Wheat Flours (not certified for niacin) in agreement (90-105%) with their respective values reported in the literature. Several commercial wheat flours showed a broad 260 nm interference, resulting in high niacin values. Niacin recoveries from spiked soy-based liquid infant formulas ranged from 95-107% with the ArSCX-SPE column. Calibration curves of niacin were linear up to 400 micrograms/mL, with a detection limit of 0.2 microgram/mL.

Hepatitis A among schoolchildren in a US-Mexico border community.

OBJECTIVES: A cross-sectional study investigated the association of hepatitis A seropositivity with environmental and personal risk factors among children in a United States-Mexico border community. METHODS: Hepatitis A serological markers and a questionnaire identifying risk factors were evaluated for 523 primary school children. RESULTS: Of the children studied, 16.9% tested positive for total antihepatitis A virus. Risk factors included being in the first grade, low maternal educational attainment, living in Mexico for more than 6 months, household crowding, and inadequate excreta disposal systems. CONCLUSIONS: To decrease enteric disease, improvements in excreta disposal infrastructures and educational programs are needed. Hepatitis A vaccine should be administered before school age.

Environmental interventions in developing countries: interactions and their implications.

This study assesses the effect of drinking water quality on diarrheal disease in good and poor sanitary conditions using a random sample of 2,355 Filipino infants over the first year of life. The study provides powerful confirmation of the importance of environmental factors on diarrhea: The effects of water quality, household sanitation, and community sanitation are strong, consistent, and statistically significant. The positive impact of improved water quality is greatest for families living under good sanitary conditions, with the effect statistically significant when sanitation is measured at the community level but not significant when sanitation is measured at the household level. Improving drinking water quality would have no effect in neighborhoods with very poor environmental sanitation; however, in areas with better community sanitation, reducing the concentration of fecal coliforms by two orders of magnitude would lead to a 40 percent reduction in diarrhea. Providing private excreta disposal would be expected to reduce diarrhea by 42 percent, while eliminating excreta around the house would lead to a 30 percent reduction in diarrhea. The findings suggest that improvements in both water supply and sanitation are necessary if infant health in developing countries is to be improved. They also imply that it is not epidemiologic but behavioral, institutional, and economic factors that should correctly determine the priority of interventions.

Drinking-water quality, sanitation, and breast-feeding: their interactive effects on infant health.

The promotion of proper infant feeding practices and the improvement of environmental sanitation have been two important strategies in the effort to reduce diarrhoeal morbidity among infants. Breast-feeding protects infants by decreasing their exposure to water- and foodborne pathogens and by improving their resistance to infection; good sanitation isolates faecal material from the human environment, reducing exposures to enteric pathogens. Taken together, breast-feeding and good sanitation form a set of sequential barriers that protect infants from diarrhoeal pathogens. As a result, breast-feeding may be most important if the sanitation barrier is not in place. This issue is explored using data from a prospective study of 2355 urban Filipino infants during the first 6 months of life. Longitudinal multivariate analyses are used to estimate the effects of full breast-feeding and mixed feeding on diarrhoeal disease at different levels of sanitation. Breast-feeding provides significant protection against diarrhoeal disease for infants in all environments. Administration of even small portions of contaminated water supplements to fully breast-fed infants nearly doubles their risk of diarrhoea. Mixed-fed and weaned infants consume much greater quantities of supplemental liquids, and as a result, the protective effect of full breast-feeding is greatest when drinking-water is contaminated. Similarly, full breast-feeding has stronger protective effects among infants living in crowded, highly contaminated settings.

PIP: Breast-feeding and good sanitation protect infants by decreasing their exposure to water- and foodborne diarrheal pathogens and by improving their resistance to infection. Using data from the Cebu Longitudinal Health and Nutrition Survey of 3080 children living in urban and rural areas of metropolitan Cebu city, Philippines, longitudinal multivariate analyses estimated the effects of full breast-feeding and mixed feeding on diarrheal disease at different levels of sanitation. 14 interviews of mothers were conducted during the third trimester of pregnancy, soon after birth, and every 2 months thereafter until the child was 2 years of age. The sample came from a 12-month cohort of all births in 17 randomly selected urban and periurban communities. Of the 2555 women recruited, 2355 had single, live births between April 1983 and May 1984. In urban Cebu, by 2 months of age 38% of the infants were mixed-fed, 19% were completely weaned, and 20% received nonnutritive liquids in addition to breast milk. The infants who were fully breast-fed dropped to fewer than 10% by the end of the first 6 months. During the first 6 months of life of the weaned children, breast-milk substitutes accounted for 88% of the total weight consumed at 2 months; 75% at 6 months. About half of the mixed-fed infants consumed breast-milk substitutes at 2 months of age. Approximately a quarter of those given the substitutes were exposed to milk products that had been stored without refrigeration for over an hour. By 4 months of age, semisolid foods were being given to almost half of the mixed-fed and weaned infants, and improper storage was common. In the multivariate model, both breast-feeding and environmental sanitation were important determinants of diarrheal disease during the first 6 months. The protective effect of full breast-feeding relative to no breast-feeding was large and statistically significant. Mixed-feeding had a somewhat smaller, yet statistically significant effect.

Growth dynamics during the first two years of life: a prospective study in the Philippines.

This study examines determinants of growth from birth to 24 months in a sample of approximately 3000 urban and rural Filipino children. Individual, household, and community data were collected bimonthly during the Cebu Longitudinal Health and Nutrition Survey. Separate longitudinal, multivariate models were used to identify determinants of weight in children from birth to 6 months and 6-24 months of age. Previous weight, male gender, mother's height, and season of the year showed significant positive associations with weight in all models. Full and mixed breast-feeding significantly increased weight, but the effects of breast-feeding declined as children got older. Breast-feeding had a direct growth-enhancing effect in addition to its indirect effect through the prevention of diarrheal morbidity. Detrimental effects of recent diarrheal morbidity were particularly important in the older age group, but these effects were mitigated by breast-feeding. Since infant feeding variables are included in the models, the results strongly suggest an effect of diarrheal morbidity on growth independent of its known effects on infant feeding and dietary intake. Febrile respiratory infections had important detrimental effects on weight in both age groups.

Vitamin C content of foods: sample variability.

A recent survey of foods that constitute the major sources of vitamin C in the American diet yielded information on the total content of this vitamin as well as the amount of its two forms, ascorbic acid and dehydroascorbic acid (DHAA) in these foods. Samples of individual foods showed a surprising large range of vitamin content even for foods collected from the same regions of the country and from the same source. The amount of DHAA in the different foods varied from approximately 10% to 20% of the total vitamin content. The large range of values for the vitamin content in a given food suggests further that in human-diet studies, when the major sources of vitamin C are from a few foods, daily analyses are required for the necessary precision.

Can the case-control method be used to assess the impact of water supply and sanitation on diarrhoea? A study in the Philippines.

PIP: This study had 2 objectives: 1) to determine whether a case-control approach is an effective measure for assessing the effect of improved sanitation on bacterial diarrhea, and 2) to assess the effects of environmental sanitation on diarrheal disease in Cebu. The study took place during the warm, rainy months (July-September) of 1985. The study population consisted of 281 children under 2 who were treated at 1 of 16 clinics for diarrhea due to Escherichia coli, salmonella, shigella, and Vibrio cholerae. The controls were 384 children under 2 who were brought to the clinics for respiratory ailments and did not have diarrhea. Environmental sanitation was classed as "good" if the bacterial count in the water supply was low (i.e., water was obtained from the municipal water supply or bore holes) and if excreta disposal was adequate (i.e., there were flush toilets, sealed latrines, or pit latrines). Water quantity was measured by the number of times the child was bathed. The effects of the exposure variables on the study children were determined by logistic regression analyses adjusted for confounding variables, which included sex, educational level of the household, breast feeding, attendance at well-baby clinics, number of children under 5 in the household, and frequency of bathing the child. The results of the study showed that improved sanitation reduced the episodes of bacterial diarrhea by 40%, and that case-control studies with sample sizes of about of about 500 cases and 500 controls are adequate to detect disease reductions of 33% or more.^ieng

Liquid chromatographic determination of amprolium in poultry feed and premixes using postcolumn chemistry with fluorometric detection.

Two extraction and liquid chromatographic procedures are presented which separate amprolium from compounds in poultry feed or premixes that could interfere with its fluorometric determination. The procedures are based on earlier work on the determination of thiamine in food samples. Amprolium is extracted from feed with a hexane-aqueous sulfosalicylic acid mix, separated on a C18 column, and detected fluorometrically after postcolumn derivatization. For premixes, water extraction is used. Values for the amprolium content of poultry feed obtained with these procedures are in good agreement with those obtained with AOAC official methods. It is suggested that these methods with suitable modifications may be of use for routine analysis of amprolium in feeds. The overall methods are rapid and appear to give reasonable results.

Application and flexibility of robotics in automating extraction methods for food samples.

Laboratory robotic technology has made it possible to automate the manually intensive operations associated with the extraction of vitamins from food. The modular approach to robotics allows the conversion from one extraction procedure to another by a simple addition or replacement of a module plus reprogramming. This is illustrated for the extraction of vitamins C and B1 from food samples. Because many of the organic micronutrients are unstable, storage and extraction conditions must be established to stabilize labile compounds if the full capabilities of robotics are to be realized.

HPLC analysis with fluorometric detection of vitamin C in food samples.

A high performance liquid chromatographic (HPLC) procedure has been developed for the analysis of ascorbic acid and dehydroascorbic acid in complex matrices. Separation is accomplished with an anion-exchange resin and fluorescent detection is achieved through post-column inline chemistry, involving oxidation of ascorbic acid to dehydroascorbic acid followed by reaction with o-phenylenediamine to form a fluorescent product. Lower limits of detection for both forms of vitamin C are well below the levels found in the usual food sources of this vitamin. The extraction procedures developed yield clean samples for analysis with minimal loss of the vitamers during the analytical procedures. Recoveries are in the range of 90-107%. The results obtained with this HPLC procedure agree well with those obtained with a modified version of the classical procedure of Deutsch and Weeks. A variety of foods including fruit juices, vegetables, and fruits were analyzed.

Liquid chromatographic determination of vitamin B-6 in foods.

Chromatographic analysis for vitamin B-6 in complex samples imposes certain requirements on the analyst, who must extract completely the bound, unstable vitamers without loss, remove interfering compounds, and provide clean extracts for analysis. The analyst also has to contend with the problems inherent in all methods, such as sample collection, storage, preparation, and homogenization. However, chromatography provides a means of identifying and quantitating all forms of the vitamin, and thus provides the possibility of addressing the problem of the bioavailability of specific vitamers. It also allows automation, which is absolutely essential in coping with the large numbers of samples that are generated in areas such as quality control. These factors are all addressed here, and chromatographic results for various meat and other food products are presented to illustrate the variations in vitamin content that occur from sample to sample, the agreement with microbiological results, and that liquid chromatography (LC) has come of age in dealing with complex biological samples, such as food and food products.