Makhan Maharjan

Groundwater Arsenic Contamination, Its Health Impact and Mitigation Program in Nepal

Abstract About 47% of Nepals total population is living in Terai region and 90% of them are relying on groundwater as their major source of drinking water. About 200,000 shallow tubewells have been installed by different agencies in 20 Terai districts, serving 11 million people. Recently, arsenic contamination of groundwater has been recognized as a public health problem in Nepal. This has sensitized government, national and international nongovernment organizations working on water quality sector to carry out water quality assessment for arsenic in the affected communities. So far, 15,000 tubewells has been tested where 23% samples exceeded World Health Organization guideline value of 10 µg/L and 5% exceeded “Nepal Interim Arsenic Guideline” of 50 µg/L. It is estimated that around 0.5 million people in Terai are living at risk of arsenic poisoning (>50 µg/L). Some recent studies have reported the prevalence of dermatosis related to arsenicosis from 1.3 to 5.1% and the accumulation of arsenic in biological samples like hair and nail much higher than the acceptable level. Though some steps are being taken by government and private organizations to combat the problem, it has not been able to cover all the affected communities. Nepal still needs more research work on arsenic occurrence and effects and mitigation programs simultaneously.

Design for sustainable development--household drinking water filter for arsenic and pathogen treatment in Nepal.

In the last 20 years, the widespread adoption of shallow tubewells in Nepal Terai region enabled substantial improvement in access to water, but recent national water quality testing showed that 3% of these sources contain arsenic above the Nepali interim guideline of 50 μ g/L, and up to 60% contain unsafe microbial contamination. To combat this crisis, MIT, ENPHO and CAWST together researched, developed and implemented a household water treatment technology by applying an iterative, learning development framework. A pilot study comparing 3 technologies against technical, social, and economic criteria showed that the KanchanTM Arsenic Filter (KAF) is the most promising technology for Nepal. A two-year technical and social evaluation of over 1000 KAFs deployed in rural villages of Nepal determined that the KAF typically removes 85–90% arsenic, 90–95% iron, 80–95% turbidity, and 85–99% total coliforms. Then 83% of the households continued to use the filter after 1 year, mainly motivated by the clean appearance, improved taste, and reduced odour of the filtered water, as compared to the original water source. Although over 5,000 filters have been implemented in Nepal by January 2007, further research rooted in sustainable development is necessary to understand the technology diffusion and scale-up process, in order to expand access to safe water in the country and beyond.

Mutual interaction between nutritional status and chronic arsenic toxicity due to groundwater contamination in an area of Terai, lowland Nepal

Objective: To reveal the inter-relationship between nutritional status and arsenic toxicity. Design: Cross-sectional study. Setting: A survey in an area of lowland Nepal, where a high prevalence of both skin manifestation and malnutrition was observed. Daily arsenic intake was estimated by measuring the arsenic concentration and daily consumption of the drinking water. Participants: Adult villagers (248 men and 291 women). About half were classified as “underweight” (body mass index <18.5), indicating poor nutritional status. Main results: Arsenic intake was negatively correlated with body mass index and substantially increased the prevalence of underweight individuals, among whom the prevalence of skin manifestations was 1.65-fold higher than normal weight individuals. When exposure level was considered, the prevalence of skin symptoms was consistently higher in the underweight than in the normal group. Although enhanced susceptibility in men was apparent by the increased prevalence of cutaneous symptoms, no sex difference was observed in the prevalence of underweight individuals related with exposure to arsenic. Conclusions: The present data suggested that exposure to arsenic is associated with an increased prevalence of underweight, a serious health problem in developing countries, which in turn is associated with increased skin manifestation of arsenic poisoning.

Pathways leading to early growth faltering: an investigation into the importance of mucosal damage and immunostimulation in different socio-economic groups in Nepal

Early childhood growth retardation persists in developing countries despite decades of nutritional interventions. Adequate food is necessary, but not sufficient, to ensure normal growth where there is ubiquitous exposure to infection. Pathways associated with infection, small intestinal mucosal damage and chronic immunostimulation remain largely undemonstrated in countries other than The Gambia. We conducted a longitudinal study of one squatter and one middle-class group (n 86, 3-18 month olds) to assess these relationships in Nepal. Growth, mucosal damage index (MDI; urinary lactose:creatinine ratio adjusted for body weight), morbidity reports, and blood concentrations of albumin, alpha-1-acid glycoprotein, IgG and Hb, were recorded monthly. Growth status worsened dramatically from 6 to 18 months, with squatters more stunted (height-for-age Z-score (HAZ), P<0.001) and underweight (weight-for-age Z-score (WAZ), P=0.009) than middle class. IgG increased with age, was elevated in squatter children, and negatively related to WAZ (P=0.034). MDI showed significant negative associations with growth performance, explaining 9 and 19% of height and weight deficits (DeltaHAZ, P=0.004; DeltaWAZ, P<0.001). Unexpectedly, these associations were weaker in squatter children, namely in the group which showed poorer growth, elevated morbidity, greater pathogen exposure (IgG) and higher MDI (P<0.001). In Nepal, as in The Gambia, children exhibit poor growth, mucosal damage and immunostimulation. The relative impact of pathways associated with infection and undernutrition may, however, differ across socio-economic groups: in poorer children, the impact of mucosal damage and immunostimulation could be masked by nutritional constraints. This has important implications for public health interventions.

Gender differences in dietary intake among adults of Hindu communities in lowland Nepal: assessment of portion sizes and food consumption frequencies

Objective:To elucidate gender differences in dietary intake among adults in lowland Nepalese communities.Subjects and methods:For 122 male and 195 female subjects aged 20 years and over from 94 randomly selected households, interviews using a 19-item food frequency questionnaire were conducted. To determine the portion sizes of these foods, the samples consumed by 56 subjects in a full 1-day period were weighed. Energy expenditure was estimated by time spent on daily activities.Results:Gender differences in per-day energy and protein intakes were related to sex differences in body size and energy expenditure. Apparent gender differences in the crude intakes disappeared when they were expressed by nutrient density (mg or μg/MJ) since micronutrient intakes were significantly correlated with energy intake. However, males’ iron intake was larger even after adjustment for energy intake, attributing to their larger portion sizes of commonly consumed staple foods and higher frequencies of consuming luxury foods (fish and tea).Conclusion:The intrahousehold unequal distribution of food incurs risk of iron deficiency among female subjects.Sponsorship:This study was financially supported by the Ajinomoto Foundation for Dietary Culture and the Alliance for Global Sustainability Program.

Significant sex difference in the association between C-reactive protein concentration and anthropometry among 13- to 19-year olds, but not 6- to 12-year olds in Nepal

Life history theory predicts a trade-off between immunostimulation and growth. Using a cross-sectional study design, this study aims to test the hypothesis that C-reactive protein (CRP) is negatively associated with height-for-age z-scores (HAZ scores) and BMI-for-age z-scores (BAZ scores) among 6- to 19-year olds (N = 426) residing in five Nepalese communities. Dried blood spot (DBS) samples were collected and assayed for CRP using an in-house enzyme immunoassay (EIA). Sex- and age-group-specific CRP quartiles were used to examine its association with growth in linear mixed-effects (LME) models. A significant difference was found in the proportion of elevated CRP (>2 mg/L, equivalent to ∼3.2 mg/L serum CRP) between 13- and 19-year-old boys (12%) and girls (4%). Concentrations of CRP were positively associated with HAZ score among adolescent (13-19 years) boys, which may indicate that individuals with greater energy resources have better growth and a better response to infections, thus eliminating the expected trade-off between body maintenance (immunostimulation) and growth. Adolescent boys with low BAZ and HAZ scores had low CRP values, suggesting that those who do not have enough energy for growth cannot increase their CRP level even when infected with pathogens. Among adolescent girls a positive association was observed between CRP and BAZ scores suggesting the possible effects of chronic low-grade inflammation due to body fat rather than infection. The association between CRP and growth was less evident among children (6-12 years) compared with adolescents, indicating that the elevated energy requirement needed for the adolescent growth spurt and puberty may play some role.

Prevalence and risk factors of soil-transmitted helminth infection in Nepal.

BACKGROUND The purpose of this study is to evaluate the prevalence and intensity and examine the risk factors of soil transmitted helminth (STH; i.e., roundworm [Ascaris lumbricoides], hookworms [Ancylostoma duodenale and Necator americanus], and whipworm [Trichuris trichiura]) infections in Nepal. METHODS Five hundred and ninety-four adults (256 men and 338 women) were selected via convenience sampling from five communities in Nepal. The Kato-Katz method was used to assess the prevalence and intensity of STH infection in this population. RESULTS Prevalence of STH infection ranged from 3.3% in Birendranagar in Chitwan, 3.5% in Kuleshor in Kathmandu, 11.7% in Kanyam in Ilam, 17.0% in Dhikurpokhari in Kaski and 51.4% in Khokana in Lalitpur District [corrected]. Multivariable regression analysis revealed that not using soap for hand-washing was significantly associated with the prevalence and infection intensity of roundworm, hookworms and whipworm. Similarly, not wearing sandals or shoes outside was significantly associated with the prevalence and infection intensity of roundworm and hookworms, but not with infection intensity of whipworm. Literacy, being underweight or overweight, anemia and occupation were not associated with prevalence and intensity of roundworm and hookworms infection, but there was an association between occupation and the prevalence of whipworm infection. CONCLUSION STH infection was associated with individual hygiene behavior, but not with nutritional status or socio-demographic characteristics. Health policy focusing on changing individual hygiene behaviors might be useful in addressing STH infection in Nepal.