Start Submission Become a Reviewer

Reading: Co-occurrence of microcystin and cylindrospermopsin in hypereutrophic Mahakanadarawa and Nac...

Download

A- A+
Alt. Display

Research Articles

Co-occurrence of microcystin and cylindrospermopsin in hypereutrophic Mahakanadarawa and Nachchaduwa reservoirs

Authors:

M. H. M. A. S. V. Gunawardana,

University of Ruhuna, LK
X close

M. M. Wijesooriya,

University of Ruhuna, LK
X close

G. W. A. P. Randima,

University of Ruhuna, LK
X close

K. S. S. Atapaththu,

University of Ruhuna, LK
X close

K. Sanjaya,

University of Ruhuna, LK
X close

K. Masakorala,

University of Ruhuna, LK
X close

S. M. K. W. Gamage

University of Ruhuna, LK
X close

Abstract

Microcystins (MCs) and cylindrospermopsin (CYN) are the most abundant toxins produced by cyanobacteria in tropical freshwaters. We studied the spatial distribution of MC and CYN in two multipurpose reservoirs, Mahakanadarawa and Nachchaduwa in Anuradhapura district in Sri Lanka in September 2020.  Fourteen water quality parameters, phytoplankton composition, chlorophyll-a, MC and CYN concentrations were analyzed in triplicate in 25 sampling sites from each reservoir. Both reservoirs were at hypereutrophic status.  Microcystis was the dominant cyanobacteria with 0-3.75 x 103 cell/mL in Mahakanadarawa and 1-7 x 103 cell/mL in Nachchaduwa. Besides Microcystis, no other potential MC-producing cyanobacteria were observed. In Mahakanadarawa, MC was detected in the range of 0.11-1.63 µg/L which was above the WHO permissible level (1.0 µg/L) for drinking water. Although comparatively high Microcystis cell density was present in Nachchaduwa, its MC concentration was low (0.06-0.17 µg/L). The CYN concentration in Nachchaduwa was above the WHO permissible level (0.7 µg/L) for drinking water. It was 0.20-1.02 µg/L in Nachchaduwa and 0.03-0.08 µg/L in Mahakanadarawa. We did not observe any potential CYN-producing cyanobacteria in either of the reservoirs. There was no relationship between the spatial distribution pattern of MC and Microcystis cell density in both reservoirs. Although the majority of physico-chemical properties of water indicated suitability for drinking, co-occurrence of high concentrations of MC and CYN indicated their unsuitability for drinking. Hence, this study highlights the necessity for routing detection of cyanotoxins in both reservoirs. Further, our findings alarm potential health risks for the local community that relies on Mahakanadarawa and Nachchaduwa reservoirs for drinking, irrigation and fisheries.
How to Cite: Gunawardana, M.H.M.A.S.V., Wijesooriya, M.M., Randima, G.W.A.P., Atapaththu, K.S.S., Sanjaya, K., Masakorala, K. and Gamage, S.M.K.W., 2022. Co-occurrence of microcystin and cylindrospermopsin in hypereutrophic Mahakanadarawa and Nachchaduwa reservoirs. Journal of Science of the University of Kelaniya Sri Lanka, 15(1), pp.67–97. DOI: http://doi.org/10.4038/josuk.v15i1.8052
Published on 05 Jul 2022.
Peer Reviewed

Downloads

  • PDF (EN)

    comments powered by Disqus