Physico-Chemical and Bacteriological Quality of the Vegetable Watering Water in the Dschang Town, Cameroon

Ntangmo Tsafack Honorine, Temgoua Emile, Njine Thomas

Laboratory of Applied Biology and Ecology,Department of Animal Biology, Faculty of Sciences, University of Dschang, PO Box 67Dschang, Cameroon.
Laboratory of General Biology, Department of Animal Biology and Physiology, Faculty of Sciences, University of Yaoundé I, PO Box 812 Yaoundé, Cameroon.
Laboratory of Soil Analysis and Environment Chemistry, Department of Soil Sciences, Faculty of Agronomy and Agricultural Sciences, University of Dschang, PO Box 222 Dschang, Cameroon.

DOI: 10.4236/jep.2012.328110                

Abstract

Market gardening, in the swampy lowlands of the Dschangcity, plays an important role in terms of providing employment, and supply the city with fresh products. However, waterborne diseases, which occur in the city, are both attributed to the bad quality of drinking water and sanitation practices. This work aims to characterize watering waters of crop, to assess the health risks associated with the use of these waters. Water from eleven streams and five wells used to irrigate crops were sampled and analyzed once a week for a month. Analyses focused on physico-chemical parameters (temperature, suspended matter, pH, electrical conductivity, COD, BOD₅, NO^-₃ , Al, Fe, Cu, Ni), parasitological (helminthes eggs) and bacteriological (total coliforms, fecal coliforms, fecal streptococcus). The results show that, the physico-chemical quality of well waters generally approaches the WHO standards of crop watering water. The physico-chemical of streams waters and bacteriological quality of wells and streams waters are bad, according to WHO guide. These bad quality waters could contaminate crops, some of which are eaten raw, which is surely a cause of the outbreak of waterborne diseases in the city. The waters from streams are more affected. The pretreatment of the water before use for irrigation of vegetables is highly recommended.

Keywords

Watering Water Quality; Urban Market Gardening; Sanitary Risks

1. Introduction

Dschang is an university town with rapid demographic growth. This town covers a surface area of more than 1300 hectares, with an estimated population of about 109,556 in habitants [1]. There are many swampy areas in this town which are valorized by the poor for dwelling in one hand and for market gardening in the other hand [2,3]. More than 10 hectares of land are cultivated in these swamps. The most highly produced vegetable include; huckle berry, tomatoes, celery, green pepper, basil, parsley, garden eggs (African aubergine), cabbage, lettuce, green-beans, leeks and carrots. About 96% of these plants are grown by watering while 4% are irrigated in the dry season. This market gardening activity is in rapid expansion within this town, and plays a vital role in the supply of the town with cheap and fresh products. This activity also provides employment for many families generally living under conditions of extreme poverty.

However, the water used for watering of these crops even those likely to be consumed raw is of doubtful qualities, where these harvest crops are sold directly to the city dwellers. The town does not have any wastewater treatment unit, so the streams receive all sorts of wastewaters originating from the city. According to an investigation carried in Dschang, about 10% of water used for watering comes from wells and 90% from untreated water of streams. Some latrines and septic tanks located along these streams are designed in a manner that their contents are emptied directly into these streams. During the rainy season, the water table rises causing floods on the cultivable lands and affecting the physical environment of wells. However, pathogenic microorganisms and chemical compounds present in the flooded waters used for watering can be a source of chemical and micro-biological contamination of the crops, and consequently harmful to the health of the consumers [4]. The potential risks of using untreated wastewater for agriculture were already highlighted [5-7]. Cholera, typhoid fever and paratyphoid epidemics already observed in Dakar and Kampala for example are allotted to the bad quality of water used in watering of crops [8]. The diagnosis made by UN-habitat [9]) and Boon [10] in Dschang proofed some cases of typhoid fever, intestinal parasites and diarrhea as recurrent diseases in the city (19% of 8000 patients listed in 2008). An increasing accusing finger is being pointer to the source of water used in watering vegetables. In addition to poor quality of drinking water, these diseases can also originate from improper hygiene and, consumption of fresh food products soiled by pathogenic micro-organisms. The quality of some water points intended for human consumption in Dschang town is well known [10-13]. Unfortunately, no data is available in regard to the composition and quality of water used in watering the crops. This study is aimed to fill this gap. It is based on the evaluation of sanitary risks related to the use of watering water, provision of helpful elements for decision making so as to ensure a market gardening without risk in Dschang town.

2. Materials and Methods

2.1. Water Collection Points

Figure 1 presents the localization of Dschang town in West Cameroun. It also presents the principal sampling points (D). In all, 16 water points used for watering of crops, 5 wells and 11 streams were selected on 10 principal market gardening sites of the town (Fiala-Foto, Tapalé, Tsinkop, Tsenfem, Ngui, Minghong, Tchoualé, Vallée, Administratif, Fiala-Foréké).

Conflicts of Interest

The authors declare no conflicts of interest.

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