Blood Lead Levels and Risk Factors for Lead Exposure in a Pediatric Population in Ho Chi Minh City, Vietnam.

Although lead recycling activities are a known risk factor for elevated blood levels in South East Asia, little is known regarding the prevalence of and risk factors for elevated blood lead levels (BLL) among the general pediatric population in Vietnam. This study is a cross-sectional evaluation of 311 children from Children's Hospital #2 in Ho Chi Minh City, Vietnam. Capillary blood lead testing was performed using the LeadCare II. Mean BLLs were 4.97 µg/dL (Standard Deviation (SD) 5.50), with 7% of the participants having levels greater than 10 µg/dL. Living in Bing Duong province (OR 2.7, 95% CI 1.4-5.6.1) or the Dong Nai province (OR 2.3, 95% CI 1.0-5.1) and having an age greater than 12 months (OR 6.0, 95% CI 3.1-11.8) were associated with higher BLLs. The prevalence of elevated BLLs in Vietnam is consistent with other SE Asian countries. Mean BLLs in Ho Chi Minh City are markedly less than those seen in a separate study of children living near lead recycling activities. Additional evaluation is necessary to better detail potential risk factors if screening is to be implemented within Vietnam.

Improving human health outcomes with a low-cost intervention to reduce exposures from lead acid battery recycling: Dong Mai, Vietnam.

This study details the first comprehensive evaluation of the efficacy of a soil lead mitigation project in Dong Mai village, Vietnam. The village's population had been subject to severe lead poisoning for at least a decade as a result of informal Used Lead Acid Battery (ULAB) recycling. Between July 2013 to February 2015, Pure Earth and the Centre for Environment and Community Development (Hanoi, Vietnam) implemented a multi-faceted environmental and human health intervention. The intervention consisted of a series of institutional and low-cost engineering controls including the capping of lead contaminated surface soils, cleaning of home interiors, an education campaign and the construction of a work-clothes changing and bathing facility. The mitigation project resulted in substantial declines in human and environmental lead levels. Remediated home yard and garden areas decreased from an average surface soil concentration of 3940mg/kg to <100mg/kg. One year after the intervention, blood lead levels in children (<6 years old) were reduced by an average of 67%-from a median of 40.4µg/dL to 13.3µg/dL. The Dong Mai project resulted in significantly decreased environmental and biological lead levels demonstrating that low-cost, rapid and well-coordinated interventions could be readily applied elsewhere to significantly reduce preventable human health harm.

Assessment of Environmental Contamination with Pathogenic Bacteria at a Hospital Laundry Facility.

Little is known about exposure to pathogenic bacteria among industrial laundry workers who work with soiled clinical linen. To study worker exposures, an assessment of surface contamination was performed at an industrial laundry facility serving hospitals in Seattle, WA, USA. Surface swab samples (n = 240) from the environment were collected during four site visits at 3-month intervals. These samples were cultured for Clostridium difficile, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant enterococci (VRE). Voluntary participation of 23 employees consisted of nasal swabs for detection of MRSA, observations during work, and questionnaires. Contamination with all three pathogens was observed in both dirty (laundry handling prior to washing) and clean areas (subsequent to washing). The dirty area had higher odds of overall contamination (≥1 pathogen) than the clean area (odds ratio, OR = 18.0, 95% confidence interval 8.9-36.5, P < 0.001). The odds of contamination were high for each individual pathogen: C. difficile, OR = 15.5; MRSA, OR = 14.8; and VRE, OR = 12.6 (each, P < 0.001). The highest odds of finding surface contamination occurred in the primary and secondary sort areas where soiled linens were manually sorted by employees (OR = 63.0, P < 0.001). The study substantiates that the laundry facility environment can become contaminated by soiled linens. Workers who handle soiled linen may have a higher risk of exposure to C. difficile, MRSA, and VRE than those who handle clean linens. Improved protocols for prevention and reduction of environmental contamination were implemented because of this study.

Migrant Workers in Agriculture: A View from Thailand.

There has been a dramatic increase in the global movement of workers during the last few decades. As Thailand has developed rapidly over the past 20 years, it has attracted laborers (both authorized and unauthorized) from the neighboring countries of Myanmar, People's Democratic Republic of Lao (Lao PDR), and Cambodia. Given that agriculture has been Thailand's most important industry, its continued growth has been dependent on migrant workers. Both crop agriculture and animal-production agriculture have employed migrant labor. Migrants have been hired to plant, weed, fertilize, spray pesticides, and harvest crops such as rice, corn, sugar cane, and cassava. They have worked at rubber and coffee plantations, as well as in the production of ornamental crops. Also, migrants have labored on pig, beef, and duck farms. There have been numerous documented health problems among migrant workers, including acute diarrhea, malaria, and fever of unknown causes. Occupational illness and injury have been a significant concern, and there has been limited health and safety training. This article reviewed the demographic changes in Thailand, studied the agricultural crops and animal production that are dependent on migrant labor, discussed the health status and safety challenges pertaining to migrant workers in agriculture, and described several recommendations. Among the recommendations, the conclusions of this study have suggested that addressing the cost for health care and solutions to health care access for migrant labor are needed.

Childhood Lead Exposure from Battery Recycling in Vietnam.

BACKGROUND: Battery recycling facilities in developing countries can cause community lead exposure. OBJECTIVE: To evaluate child lead exposure in a Vietnam battery recycling craft village after efforts to shift home-based recycling outside the village. METHODS: This cross-sectional study evaluated 109 children in Dong Mai village, using blood lead level (BLL) measurement, parent interview, and household observation. Blood samples were analyzed with a LeadCare II field instrument; highest BLLs (≥45 µg/dL) were retested by laboratory analysis. Surface and soil lead were measured at 11 households and a school with X-ray fluorescence analyzer. RESULTS: All children had high BLLs; 28% had BLL ≥45 µg/dL. Younger age, family recycling, and outside brick surfaces were associated with higher BLL. Surface and soil lead levels were high at all tested homes, even with no recycling history. Laboratory BLLs were lower than LeadCare BLLs, in 24 retested children. DISCUSSION: In spite of improvements, lead exposure was still substantial and probably associated with continued home-based recycling, legacy contamination, and workplace take-home exposure pathways. There is a need for effective strategies to manage lead exposure from battery recycling in craft villages. These reported BLL values should be interpreted cautiously, although the observed field-laboratory discordance may reflect bias in laboratory results.

Health impact assessment of urban waterway decisions.

Health impact assessments (HIA) promote the consideration of health in a wide range of public decisions. Although each HIA is different, common pathways, evidence bases, and strategies for community engagement tend to emerge in certain sectors, such as urban redevelopment, natural resource extraction, or transportation planning. To date, a limited number of HIAs have been conducted on decisions affecting water resources and waterfronts. This review presents four recent HIAs of water-related decisions in the United States and Puerto Rico. Although the four cases are topically and geographically diverse, several common themes emerged from the consideration of health in water-related decisions. Water resource decisions are characterized by multiple competing uses, inter-institutional and inter-jurisdictional complexity, scientific uncertainty, long time scales for environmental change, diverse cultural and historical human values, and tradeoffs between private use and public access. These four case studies reveal challenges and opportunities of examining waterfront decisions through a "health lens". This review analyzes these cases, common themes, and lessons learned for the future practice of HIA in the waterfront zone and beyond.

Factors influencing poisoning symptoms: a case study of vegetable farmers exposed to mixed insecticides in Prek Balatchheng Village, Cambodia.

This study aimed to identify factors influencing poisoning symptoms among 153 mixed insecticide-exposed vegetable farmers in one Cambodian village, where 153 factory workers were selected as a comparative nonexposed group. The research instruments were questionnaires and reactive-paper test kits. The majority of vegetable farmers were male, with approximately 87% of the total participants with an average age of 34 years. The personal hygiene scores of most vegetable farmers (108; 70.8%) were moderate, and knowledge scores were at poor level (131; 85.6%). Abnormally low cholinesterase (ChE) levels were detected among 119 (77.8%) farmers. Multiple logistic regression analysis was used to identify factors associated with possible poisoning symptoms. This study found that mixing an average of four to six types of insecticides (odds ratio [OR] = 4.6; P = .03) and abnormal ChE level (OR = 4.09; P = .004) was associated with central nervous system (CNS) symptoms. Age group >45 years (OR = 2.8; P = .04) and type of vegetable "other" (OR = 2.73; P = .02) were associated with gastrointestinal symptoms. Type of insecticide, organophosphates (OPs) and carbamates (CMs) (OR = 3.2; P = .04), was associated with respiratory symptoms. It is recommended that farmers should reduce insecticide spraying times, increase their use of personal protective equipment (PPE), and undergo training on insecticide use. These combined measures should improve the insecticide-related health status of vegetable farmers in this area.

Symptoms in response to controlled diesel exhaust more closely reflect exposure perception than true exposure.

BACKGROUND: Diesel exhaust (DE) exposures are very common, yet exposure-related symptoms haven't been rigorously examined. OBJECTIVE: Describe symptomatic responses to freshly generated and diluted DE and filtered air (FA) in a controlled human exposure setting; assess whether such responses are altered by perception of exposure. METHODS: 43 subjects participated within three double-blind crossover experiments to order-randomized DE exposure levels (FA and DE calibrated at 100 and/or 200 micrograms/m(3) particulate matter of diameter less than 2.5 microns), and completed questionnaires regarding symptoms and dose perception. RESULTS: For a given symptom cluster, the majority of those exposed to moderate concentrations of diesel exhaust do not report such symptoms. The most commonly reported symptom cluster was of the nose (29%). Blinding to exposure is generally effective. Perceived exposure, rather than true exposure, is the dominant modifier of symptom reporting. CONCLUSION: Controlled human exposure to moderate-dose diesel exhaust is associated with a range of mild symptoms, though the majority of individuals will not experience any given symptom. Blinding to DE exposure is generally effective. Perceived DE exposure, rather than true DE exposure, is the dominant modifier of symptom reporting.

Teacher perspectives on implementing and sustaining a handwashing promotion intervention in Western Kenyan primary schools.

School-based handwashing programs are challenging to establish and sustain, especially in low-resource settings. This qualitative study described teacher perspectives associated with implementing and sustaining a handwashing program in primary schools participating in the Nyando Integrated Child Health and Education (NICHE) project. Structured key informant interviews were conducted with teachers. Prevalent concepts and themes were grouped into themes and topic areas using an iterative, open coding approach. Forty-one teacher respondents reported favorable expectations and benefits of handwashing programs. The importance of available resources (e.g., reliable water) was cited as a primary concern. Other challenges included time and personal or institutional financial commitment necessary to ensure program sustainability. Handwashing programs in low-income, rural schools, where infrastructure is lacking and "student ambassadors" extend the intervention to the surrounding community, hold great promise to improve community health. Teachers must have adequate support and resources to implement and sustain the programs.

Improving exposure estimates by combining exposure information.

OBJECTIVES: Any exposure estimation technique has inherent strengths and limitations. In an effort to improve exposure estimates, this study developed and evaluated the performance of several hybrid exposure estimates created by combining information from individual assessment techniques. METHODS: Construction workers (n = 68) each completed three full-shift noise measurements over 4 months. Three single exposure assessment techniques [trade mean (TM), task-based (TB), and subjective rating (SR)] were used to estimate exposures for each subject. Hybrid techniques were then developed which incorporated the TM, SR, and TB noise exposure estimates via arithmetic mean combination, linear regression combination, and modification of TM and TB estimates using SR information. Exposure estimates from the single and hybrid techniques were compared to subjects' measured exposures to evaluate accuracy. RESULTS: Hybrid estimates generally were more accurate than estimates from single techniques. The best-performing hybrid techniques combined TB and SR estimates and resulted in improvements in estimated exposures compared to single techniques. Hybrid estimates were not improved by the inclusion of TM information in this study. CONCLUSIONS: Hybrid noise exposure estimates performed better than individual estimates, and in this study, combination of TB and SR estimates using linear regression performed best. The application of hybrid approaches in other contexts will depend upon the exposure of interest and the nature of the individual exposure estimates available.

Iron-deficiency anaemia in rural Cambodia: community trial of a novel iron supplementation technique.

BACKGROUND: More than 3.5 billion people are affected by iron-deficiency anaemia (IDA). Previous studies have shown that the use of iron pots in daily cooking ameliorates IDA. We report a study on the use of a novel treatment to address IDA in rural women in Cambodia, where the use of iron pots is not common. METHODS: A community-wide randomized controlled trial was conducted in the village of Preak Ruessei, Kandal Province, Cambodia. Rural women (n = 189) were enrolled and randomly assigned by household to one of three groups: (i) control, (ii) iron treatment with no follow-up and (iii) iron treatment with follow-up visits to provide IDA education. Haemoglobin, serum iron and C-reactive protein concentrations were measured at baseline, 3 and 6 months. A reusable fish-shaped iron ingot was distributed to the two treatment groups and participants were directed to use them daily for cooking. We hypothesized that iron from the ingot would leach iron into food providing an effective iron source. RESULTS: Blood iron levels were higher in women in the iron fish plus follow-up at 3 months compared with controls, but this was not maintained. At 6 months, haemoglobin and serum iron had fallen in all groups and the proportion of anaemic women had increased. CONCLUSIONS: This study shows that the iron ingot was effective in the short but not longer-term against IDA. Though a novel treatment option, further research is warranted to determine bioavailability of leached iron and whether or not the surface area is large enough for sufficient iron leaching.

Enhancing a safe water intervention with student-created visual aids to promote handwashing behavior in Kenyan primary schools.

The Nyando Integrated Child Health Education (NICHE) project was a collaborative effort by the U.S. Centers for Disease Control and local partners to assess the effectiveness of multiple interventions for improving child survival in western Kenya. To increase handwashing in schools, NICHE trained teachers and installed handwashing stations with treated water and soap in 51 primary schools. This cluster-randomized trial evaluated an additional educational strategy (a poster contest themed, "Handwashing with Soap") to improve handwashing behavior in 23 NICHE primary schools. Pupils were engaged in the poster development. Pupil handwashing behavior was observed unobtrusively at baseline and after four months. Intervention schools displayed a significant increase in the number of handwashing stations and proportion of teacher-supervised stations over the study period. No significant between-group differences of intervention in handwashing frequency, soap availability, or visibility of handwashing stations was observed. Despite finding a limited effect beyond the NICHE intervention, the trial appeared to promote sustainability across some measures.

Association of weight at enlistment with enrollment in the Army Weight Control Program and subsequent attrition in the Assessment of Recruit Motivation and Strength Study.

The ongoing obesity epidemic has made recruiting qualified Army applicants increasingly difficult. A cohort of 10,213 Army enlisted subjects was enrolled in the Assessment of Recruit Motivation and Strength (ARMS) study from February 2005 through September 2006. Overweight recruits obtained a waiver for enlistment (n = 990) if they passed a screening physical fitness test. Recruits were evaluated for enrollment into the Army Weight Control Program (AWCP) and discharged during the 15 months following enlistment. Enrollment was higher among overweight recruits than recruits who met entrance standards (men: adjusted OR = 13.3 [95% CI: 10.3, 17.2]; women: adjusted OR = 3.6 [3.3, 3.9]). Although the discharge frequency was higher in the waiver group than in those who met standards (25.4% versus 19.9%, p < 0.001), there were only 10 (0.5% of total) discharges directly attributed to weight. Granting overweight waivers through the ARMS program increases enrollment to the AWCP but has little effect on weight-related attrition.

Influenza vaccination and sick leave practices and perceptions reported by health care workers in ambulatory care settings.

We examined annual influenza vaccination and sick leave practices and perceptions among 627 health care workers (HCWs) in ambulatory care settings in King County, Washington using a self-report questionnaire. Most medical practitioners (85%), but fewer other HCWs (nurses, nurse's aides, allied health professionals, administrative; 55%-64%) reported receiving an annual influenza vaccination; only 31% of HCWs reported routinely taking sick leave for influenza-like illness.

Notifiable infectious disease reporting awareness among physicians and registered nurses in primary care and emergency department settings.

This study examined knowledge about notifiable infectious disease reporting among physicians and registered nurses (RNs) in primary care and emergency department settings in King County, Washington. In 2005, a total of 165 physicians and 170 RNs completed a questionnaire to assess knowledge, training and feedback regarding notifiable infectious disease reporting. Only 55% of the physicians and 63% of the RNs were aware of reporting procedures within their institution. Awareness was higher when employer-provided training had been provided. Our findings indicate that employer training can improve reporting knowledge.

Work-related carpal tunnel syndrome in Washington State workers' compensation: utilization of surgery and the duration of lost work.

BACKGROUND: Work-related carpal tunnel syndrome (CTS) is a leading cause of lengthy disability. METHODS: This population-based retrospective cohort study used Washington State workers' compensation claims for CTS to characterize associations between utilization of CTS surgery and duration of lost work. The sample included all claims (n = 8,224) filed during 1990-1994 (followed through 2000) and receiving lost-work compensation. RESULTS: Sixty-four percent of studied workers had CTS surgery. Among workers with >1 month of lost work, the total duration was much shorter when workers had surgery, versus those who did not (median 4.3 and 6.2 months, respectively; P < 0.001); there was no difference when disability extended >6 months. When workers had surgery, disability was less likely to end before 6 months if non-CTS conditions were present, surgery occurred >3 months after claim filing, or employment was in an industry with high incidence of CTS; disability was more likely to end if the diagnosing provider and operating surgeon had higher CTS claims volume. Physical and rehabilitation medicine services were associated with lower probability of returning to work, with or without surgery. CONCLUSIONS: There is a need to scrutinize the role of surgery and physical-rehabilitation medicine modalities in the management of CTS covered by workers' compensation. The findings suggest disability can be minimized by establishing the CTS diagnosis as early as possible and, if surgery is appropriate, conducting surgery without substantial delay and maximizing post-operative efforts to facilitate return to work. Use of surgery >6 months after filing should be considered with great caution.

Opioid use for chronic low back pain: A prospective, population-based study among injured workers in Washington state, 2002-2005.

OBJECTIVES: To determine (1) the natural history of prescription opioid use, (2) the predictors of long-term opioid use, and (3) the association between opioid dose and pain and function in a large cohort of workers with recent back injuries. METHODS: Prospective cohort of workers with back injuries (N=1883) interviewed 18 days (median) and 1 year after claim submission. Detailed pharmacy data were obtained from computerized records of paid bills. RESULTS: Forty-two percent of workers (781/1843) received an opioid in the year after injury, most (694/781, 89%) at or shortly after the first medical visit for the injury. Of these, most (410/694, 59%) received opioids only within the first quarter after injury, whereas 16% (111/694) received opioids for 4 quarters. Among these long-term users, total morphine equivalent dose (MED) increased significantly (P<0.01) from the first (mean, 2364 mg; standard deviation, 4019 mg) to the fourth (mean, 3824 mg; standard deviation, 5998 mg) quarter. Improvement by at least 30% in pain and function measure scores occurred in only 26% (95% confidence interval 18%-36%) and 16% (95% confidence interval 10%-25%), respectively, of long-term users. Opioid doses increased substantially over time in all but those in whom function improved. After adjustment for baseline pain, function, and injury severity, the strongest predictor of longer term opioid prescription was total MED in the first quarter. Workers receiving at least 40 mg MED per day in the first quarter had 6-fold odds of receiving longer-term opioids. DISCUSSIONS: For the small group of workers with compensable back injuries who receive opioids longer-term (111/1843, 6%), opioid doses increase substantially and only a minority shows clinically important improvement in pain and function. The amount of prescribed opioid received early after injury strongly predicts long-term use. More research is needed to understand clinical decisions to continue or increase opioid therapy after back injury.

Indicators of hearing protection use: self-report and researcher observation.

Hearing protection devices (HPD) are commonly used to prevent occupational noise-induced hearing loss. There is a large body of research on hearing protection use in industry, and much of it relies on workers' self-reported use of hearing protection. Based on previous studies in fixed industry, worker self-report has been accepted as an adequate and reliable tool to measure this behavior among workers in many industrial sectors. However, recent research indicates self-reported hearing protection use may not accurately reflect subject behavior in industries with variable noise exposure. This study compares workers' self-reported use of hearing protection with their observed use in three workplaces with two types of noise environments: one construction site and one fixed industry facility with a variable noise environment, and one fixed industry facility with a steady noise environment. Subjects reported their use of hearing protection on self-administered surveys and activity cards, which were validated using researcher observations. The primary outcome of interest in the study was the difference between the self-reported use of hearing protection in high noise on the activity card and survey: (1) over one workday, and (2) over a 2-week period. The primary hypotheses for the study were that subjects in workplaces with variable noise environments would report their use of HPDs less accurately than subjects in the stable noise environment, and that reporting would be less accurate over 2 weeks than over 1 day. In addition to noise variability, other personal and workplace factors thought to affect the accuracy of self-reported hearing protection use were also analyzed. This study found good agreement between subjects' self-reported HPD use and researcher observations. Workers in the steady noise environment self-reported hearing protection use more accurately on the surveys than workers in variable noise environments. The findings demonstrate the potential importance of noise exposure variability as a factor influencing reporting accuracy.

Predictors of hearing protection use in construction workers.

OBJECTIVES: Although noise-induced hearing loss is completely preventable, it remains highly prevalent among construction workers. Hearing protection devices (HPDs) are commonly relied upon for exposure reduction in construction, but their use is complicated by intermittent and highly variable noise, inadequate industry support for hearing conservation, and lax regulatory enforcement. METHODS: As part of an intervention study designed to promote HPD use in the construction industry, we enrolled a cohort of 268 construction workers from a variety of trades at eight sites and evaluated their use of HPDs at baseline. We measured HPD use with two instruments, a questionnaire survey and a validated combination of activity logs with simultaneous dosimetry measurements. With these measurements, we evaluated potential predictors of HPD use based on components of Pender's revised health promotion model (HPM) and safety climate factors. RESULTS: Observed full-shift equivalent noise levels were above recommended limits, with a mean of 89.8 +/- 4.9 dBA, and workers spent an average of 32.4 +/- 18.6% of time in each shift above 85 dBA. We observed a bimodal distribution of HPD use from the activity card/dosimetry measures, with nearly 80% of workers reporting either almost never or almost always using HPDs. Fair agreement (kappa = 0.38) was found between the survey and activity card/dosimetry HPD use measures. Logistic regression models identified site, trade, education level, years in construction, percent of shift in high noise, and five HPM components as important predictors of HPD use at the individual level. Site safety climate factors were also predictors at the group level. CONCLUSIONS: Full-shift equivalent noise levels on the construction sites assessed were well above the level at which HPDs are required, but usage rates were quite low. Understanding and predicting HPD use differs by methods used to assess use (survey versus activity card/dosimetry). Site, trade, and the belief that wearing HPD is not time consuming were the only predictors of HPD use common to both measures on an individual level. At the group level, perceived support for site safety and HPD use proved to be predictive of HPD use.

Residual methamphetamine in decontaminated clandestine drug laboratories.

This pilot cross-sectional study examined three previously decontaminated residential clandestine drug laboratories (CDLs) in Washington State to determine the distribution and magnitude of residual methamphetamine concentrations relative to the state decontamination standard. A total of 159 discrete random methamphetamine wipe samples were collected from the three CDLs, focusing on the master bedroom, bathroom, living room, and kitchen at each site. Additional samples were collected from specific non-random locations likely to be contacted by future residents (e.g., door knobs and light switches). Samples were analyzed for methamphetamine by EPA method 8270 for semivolatile organic chemicals. Overall, 59% of random samples and 75% of contact point samples contained methamphetamine in excess of the state decontamination standard (0.1 micro g/100 cm(2)). At each site, methamphetamine concentrations were generally higher and more variable in rooms where methamphetamine was prepared and used. Even compared with the less stringent standard adopted in Colorado (0.5 micro g/100cm(2)), a substantial number of samples at each site still demonstrated excessive residual methamphetamine (random samples, 25%; contact samples, 44%). Independent oversight of CDL decontamination in residential structures is warranted to protect public health. Further research on the efficacy of CDL decontamination procedures and subsequent verification of methods is needed.