International Journal of Aquaculture, 2013, Vol.3, No.10, 43
-
48
http://ija.sophiapublisher.com
43
Research Report Open Access
Toxicity Evaluation of Waste Treatment Plant of Textile Effluent Using Fish:
Nile tilapia,
Oreochromis niloticus
Kassaye Balkew Workagegn
Department of Biology, College of Natural and Computational Sciences, Hawassa University, P.O. Box 5, Hawassa, Ethiopia
Corresponding author email:
kassayebalkew@gmail.com
International Journal of Aquaculture, 2013, Vol.3, No.10 doi: 10.5376/ija.2013.03.0010
Received: 24 Apr., 2013
Accepted: 28 Apr., 2013
Published: 8 May, 2013
Copyright © 2013
Workagegn. This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted
use, distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article
:
Workagegn, 2013, Toxicity Evaluation of Waste Treatment Plant of Textile Effluent Using Fish: Nile tilapia,
Oreochromis niloticus
,
International Journal of
Aquaculture, Vol.3, No.10 43-48 (doi: 10.5376/ija.2013.03.0010)
Abstract
The experiment was conducted to evaluate the acute toxicity level of effluents from inlet and outlet of the biological
lagoons of Hawassa Textile waste treatment plant using Nile tilapia,
Oreochromis niloticus
as test organism. Data for 24hrs, 48hr,
72
hrs and 96hrs were recorded, and were analysed to determine the effects of toxicants of the effluent on behavioural responses and
survival rate of
Oreochromis niloticus
.
The results revealed that normal swimming behaviours were observed on the fish stocked at
lower effluent concentration, while erratic swimming, gasping and frequent surfacing behavioural responses were observed on the
fish stocked at higher effluent concentration. There was no fish mortality in control and 10% (v/v) outlet effluent concentration. The
highest percentage mortality was observed at 100% (v/v) inlet effluent concentration followed by 100% (v/v) outlet and 40% (v/v)
inlet effluent concentrations. The 96hrs fifty present lethal concentration (LC
50
)
and acute toxicity unit (ATU) values for inlet and
outlet wastewater were 30.5% (v/v), 3.279, 71.5% (v/v) and 1.399, respectively. The safe effluent concentration for both inlet and
outlet wastewater is set to be 3.05% and 7.15%, respectively. As a whole the present results revealed that the total efficiency level of
the treatment plant to remove toxicants was 57.33% (v/v). However, efficiency of the treatment plant should be improved to use the
water for irrigation and other domestic purposes; otherwise, the use of the wastewater at present condition is unsafe.
Keywords
Oreochromis niloticus
;
Percentage mortality; Textile effluent; Toxicity test
Introduction
Aquatic ecosystems are exposed to a number of point
and non-point sources of pollutants particularly form
industries, swages treatment plants, drainage from
urban and agricultural areas (Walker et al., 2006).
Industries are among the most important point source
of pollutants and discharge huge amount of waste
substances into aquatic ecosystems. They can generate
both organic and inorganic wastes, which could be
alter all or parts of biological, physical and chemical
characteristics of the receiving water bodies
(
Gomez et al., 2008). Depending on the dose and
exposure time, some of these pollutants are toxic to
living systems and cause a serious impairment to
aquatic life (Walker et al., 2006; Gomez et al., 2008;
Ogundrian et al., 2010). This is because, in the
receiving water bodies, pollutants could accumulate in
water, sediment and living systems. They also
accumulate in food chain and thus cause adverse
effects in aquatic systems (Walker et al., 2006).
Textile, tannery and flowering industries are currently
some of the growing sectors in Ethiopia. As they are
newly growing industries their treatment plants are
inefficient to removal toxic substances, even some of
them lack treatment plant. Instead, their waste
substances directly or indirectly discharged to the
surrounding water bodies and become potential source
of pollutants. Among these, textile industry is one of
the major sources of pollutants to the receiving water
bodies due to the fact that it requires high volume of
water that eventually results in high volume of
wastewater (Yusuff and Sonibare, 2004; Roy et al., 2010).
Depending on the types of raw materials and daily
products, textile industry employs variety of chemicals
such as detergents and dyes (Roy et al., 2010). The
authors also stated that the quantities and characteristics
of discharged textile effluent vary depending on the
amount of water consumed, and types and amount of
raw materials used.
Textile industry produces huge amount of wastewater
particularly during wet processing such as sizing,
fabric preparation, dyeing, printing and finishing