Comprehensive assessment of handwashing and faecal contamination among elementary school children in an urban slum of Indonesia.

OBJECTIVE: Globally, the challenge of handwashing with soap (HWWS) still exists despite the importance of HWWS being shown previously. This study aimed to evaluate faecal contamination on the hands of children and to find factors related to faecal contamination from handwashing techniques, HWWS, knowledge and awareness of water, sanitation, and hygiene (WASH), and a comprehensive WASH index. METHODS: The study was conducted at two elementary schools with 169 children in a densely populated area of Bandung, Indonesia. The survey involved handwashing observation using a checklist, hand bacteria sampling and questionnaires. RESULTS: Most children (98.7%) had faecal contamination. Girls had significantly fewer Escherichia coli than boys (P < 0.05). Ability in handwashing techniques, HWWS, and knowledge and awareness of WASH were poor in the lower grades. Escherichia coli counts were negatively correlated with handwashing technique (r = -0.171, P < 0.05), HWWS (r = -0.225, P < 0.01) and the WASH index (r = -0.205, P < 0.05). CONCLUSIONS: Proper handwashing technique and HWWS at appropriate times can reduce faecal contamination. Moreover, it is important that both grade-based and gender-based handwashing education be considered in elementary school education.

OBJECTIF: A l'échelle mondiale, le défi du lavage des mains au savon (HWWS) existe toujours, en dépit de l'importance révélée de ce procédé. Cette étude visait à évaluer la contamination fécale sur les mains des enfants et à trouver des facteurs liés à la contamination fécale résultant des procédés de lavage des mains, du lavage des mains au savon, de la connaissance et de la sensibilisation à l'eau, aux sanitaires et à l'hygiène (WASH), ainsi qu'un indice WASH détaillé. MÉTHODES: L'étude a été menée dans deux écoles élémentaires avec 169 enfants dans une zone densément peuplée de Bandung, en Indonésie. L'enquête comprenait l'observation du lavage des mains à l'aide d'une liste de contrôle, un échantillonnage bactérien sur les mains et des questionnaires. RÉSULTATS: La plupart des enfants (98,7%) avaient une contamination fécale. Escherichia coli était nettement moins présent chez les filles que chez les garçons (p <0,05). L'aptitude dans les techniques de lavage des mains, le lavage des mains au savon, ainsi que la connaissance et la sensibilisation au WASH étaient faibles dans les classes inférieures. Les comptages d'E. Coli corrélaient négativement avec la technique de lavage des mains (r = -0,171 ; p <0,05), le lavage des mains au savon (r = 0,225 ; p <0,01) et l'indice WASH (r= - 0,205 ; p <0,05). CONCLUSIONS: Une technique de lavage des mains appropriée et un lavage des mains au savon à des moments opportuns peuvent réduire la contamination fécale. De plus, il est important de prendre en compte l'éducation au lavage des mains basée sur le niveau et le sexe dans l'enseignement primaire.

Beneficiary of nitrifying bacteria for enhancing lettuce (Lactuca sativa) and vetiver grass (Chrysopogon zizanioides L.) growths align with carp (Cyprinus carpio) cultivation in an aquaponic system.

The aquaponic system is an alternative strategy to treat aquaculture waste and achieve food independence. Bacteria play vital roles in the aquaponic system as they can transform ammonia or ammonium into nitrite and then into nitrate, which is more favorable for bacteria, fish, and plants. The objective of this study was to determine the effect of nitrifying bacteria (Nitrosomonas europaea Winogradsky and Nitrobacter winogradskyi Winslow) on the aquaponic system in terms of water quality, nutrient availability, and productivity of carp (Cyprinus carpio), lettuce (Lactuca sativa var. crispa), and vetiver grass (Chrysopogon zizanioides L.). The experiment consisted of four treatments: aquaculture of carp as a control for fish (A), hydroponic of lettuce and vetiver grass without nutrient addition as a control for plants (B), aquaponic (carp, lettuce, vetiver grass) (C), and aquaponic with nitrifying bacteria addition (D). The results showed nitrifying bacteria addition had a significant effect on daily growth rate (DGR) and relative growth rate (RGR) of lettuce within a treatment; on the other hand, the nitrifying bacteria did not give a significant effect to RGR of vetiver grass. The growth rate, specific growth rate, and survival rate of the carp in aquaculture treatment (A) were lower than in both aquaponic treatments (C and D). Nitrifying bacteria addition in the aquaponics system had a significant effect of increasing the orthophosphate concentration. Water quality was also indicated to be better in the aquaponic system than in the aquaculture system. The integration of aquaculture and hydroponics with the addition of nitrifying bacteria enables the formation of microorganism communities, nitrate, and orthophosphate, which lead to the improvement of water quality, nutrient availability, and plant growth.

Phytoremediation of electroplating wastewater by vetiver grass (Chrysopogon zizanoides L.).

The electroplating industry generates wastewater containing a variety of heavy metals which potentially contaminate water ecosystems. The available and well-known electroplating wastewater treatments are considered as an expensive and less effective method, therefore phytoremediation was used as an alternative friendly solution. This study aims to evaluate the uptake and elimination rate of heavy metals by vetiver (Chrysopogon zizanoides L.) on metal-polluted water. Vetiver was planted in artificial electroplating wastewater containing different levels (low, medium, high) of chromium (Cr) and nickel (Ni). Water, roots, and shoots were collected periodically to determine Cr and Ni contents using Atomic Absorption Spectrometry (AAS). Metal accumulation and elimination rate, Bioconcentration Factor (BCF), Biological Absorption Coefficient (BAC), and Translocation Factor (TF) were calculated to evaluate plant's effectiveness in metal remediation processes. The results showed that vetiver (C. zizanoides L.) was able to remove 61.10% Cr and 95.65% Ni on metal-contaminated water. The highest uptake rates for Cr and Ni are 127.21 mg/kg/day and 15.60 mg/kg/day respectively, while the elimination rates for Cr and Ni tend to slow 1.09 mg/kg/day and 12.24 mg/kg/day respectively. Vetiver BCF, BAC, and TF values on Cr and Ni contaminated water were greater than 1, which indicates that vetiver work through phytoextraction and phytostabilization to treat metals. The findings showed that vetiver has promise as a phytoremediation agent thus providing implication for electroplating wastewater treatment.