Sociedad de Historia Natural Niparajá, A.C.                                                                                                

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Laboratory testing

>>> See full results here (pdf)

The results were the following:

	Reduction in bacteria E.Coli::   Above 7.6 log or 99.999996%  (first and mid effluent)
	Reduction in virus MS2:    3.8 log or 99.98%      (first effluent)  4.7 log or 99.997%      (mid effluent)

Degradation of materials of UV bucket:

The plastic degradation of the UV Bucket was tested as follows:

- Sample 1 (100mL) was taken from a bottled water sold by local water vendors (typically treated by Reverse Osmosis and UV light before being bottled). 

-  Sample 2 (100mL) was taken immediately after running 3 liters of bottled water through the UV bucket once and filling sample 3 at the water dispenser of the UV bucket. 

-  Sample 3 (100mL) was taken after leaving the ultraviolet light inside the UV bucket on for 24 hours continuously. (24 hours corresponds to 3-month normal use of 15 minutes daily). 3 liters of bottled water was run through the empty UV bucket and sample 3 was taken at the water dispenser. 

-  Sample 4 (100mL) was taken after leaving the ultraviolet light on for 7 days (7 days corresponds to 1.8 year normal use). 3 liters of bottled water was run throught the empty UV Bucket and sample 4 was taken at the UV Bucket water dispenser.

The results of the plastic degradation are satisfactory, the disinfection chamber and bucket, made of polyethylene (food grade with additive for UV resistance) do not seem to degrade after the almost 2-year accelerated use trial. Indeed no polyethylene or related plastic compounds can be found in the analyzed samples.

However we observed a rise in the level of styrene in the water after 24 and 168h, probably due to the degradation of the upper container which is not in contact with the water. This level reaches 3.6 microg/L after 24 hours and then decreases to 0.4 microg/L after 168 hours continuous use. This maximum level is well below the USEPA drinking standard of 100 microg/L for styrene. Based on these results we will opt for the better material, polyethylene, instead of polystyrene for the upper container, for the remaining 5,500 UV Buckets.

We also detect an increase in the level of acetone after 24h reaching a concentration of 120 microg/L and then decreasing after 7 days of accelerated use at 55 microg/L. We do not know so far the origin of the acetone. Acetone is primarily used as an industrial solvent. There is currently no federal health based standard or criterion for acetone in drinking water. Mild kidney toxicity was observed at some concentrations in a rat study. Based upon this rat study, the EPA developed a non-cancer toxicity value (Reference Dose or RfD) for acetone. From the RfD, DES has derived a drinking water guideline of 6,000 microg/L. Care will be taken to rinse all plastic parts for the UV Bucket more thoroughly for the remaining 5,500 and measurements of acetone will be performed again.

>>> See results of plastic degradation analysis (pdf)

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Monitoring in the field

The monitoring and evaluation of the UV Buckets in the field is a key part of this project. The monitoring plan consists of the following:

- Monthly visits to fixed beneficiaries (include interviews, observations, bacteria counts).

- Weekly random visits to beneficiaries (include observations, discussions).

- Collaboration with rural school teachers from Rural School Federation (CONAFE) to measure the impact of the project from their point of view.

- Collaboration with rural health promoters from the Ministry of Health (SSA) to measure the health impact of the UV bucket on the population (change in rate of gastro-intestinal problems in rural population).

- Collaboration with the rural stores under the Ministry of Social Affairs program (DICONSA) to report acquisition of replacement parts for UV Bucket.

The fabrication/distribution is organized in 3 campaigns (500, 2000 and 3500 UV buckets), we consider monitoring monthly 25 beneficiaries in each campaign, as presented in the table below:

The visits will consist of the following activities:

·  Determining bacteria concentration before and after the UV bucket

·  Writing observations on the condition of the UV bucket in the household

·  Recording observations on water disinfection performed by the user himself with the UV Bucket

·  Listening to the user and recording their problems, suggestions, ideas for improvements

·  Interviewing the user on the health impact of the UV bucket in their family (occurrence of gastro-intestinal diseases before and after the UV Bucket).

During campaign 1, Niparajá will also visit three random beneficiaries every week to observe the condition of the UV bucket and discuss observations, problems or suggestions with respect to the UV Bucket.

To continue the dialogue with all communities, Niparajá plans on organizing a yearly meeting with the rural mayors in each municipality of BCS. The meeting would be to listen to the mayor´s point of view on the UV Bucket project as well as reflect on other potential projects beneficial for the communities. The event would also consist of training the new rural mayors on the UV bucket to ensure their participation and active role in the long-term monitoring of the project.

Measure of impact

Niparajá will be preparing a list of indicators to measure the impact of the UV bucket on the families and communities involved in the project with the help of a summer intern in 2007.

The following topics will be considered for establishing indicators of impact:

·  Use over time of the UV Bucket by the beneficiaries

·  Bacterial counts before and after the UV bucket

·  Frequency of diarrhea among beneficiaries

·  Participation of different actors of the project in yearly trainings

·  Level of education on clean water and hygiene in communities thanks to CONAFE’s educational campaign

·  Continued inter-institutional collaboration to conduct and evaluate the project  

UV Buckets installed in Las Gallinas, March 2007

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Evaluation and systematization

The final evaluation of the project in all its aspects will be performed at the end of the two-year project with the World Bank, in the summer of 2008. This will be the time for reflecting on the lessons learned, success and failures of the project as well as recommendations for replicating the project in other states or countries.

CONAFE and Niparajá will work with experts from CONAFE at the national level to compile the experience gained in this project in a short book to be shared with NGOs and Government Institutions interested in replicating or just learning from the project.

The project’s team from Niparajá and CONAFE with the advisor

from the World Bank Mexico, Ricardo Hernández.