Cytotoxicity and genotoxicity of Cikamal and Cirengganis Rivers at Pananjung Pangandaran Nature Reserve using biomarker Allium cepa L.

River becomes eminently threatened ecosystem compared to other aquatic environments. Contamination of the aquatic environment that come from anthropogenic activities, may reduce water quality and harm living creatures which is inhabiting within. The Cikamal and Cirengganis rivers at Pananjung Pangandaran Nature Reserve play an important role as water resources for local inhabitants around the nature reserve This research aimed to compare cytotoxicity and genotoxicity of Cikamal and Cirengganis rivers based on mitotic index (MI) and type of chromosomal aberration using Allium cepa as a biomarker. The methods used in this experiment were Completely Randomized Design and observation. MI analyzed using analysis of variance (ANOVA), followed by Duncan's test. Types of chromosome aberrations were observed descriptively. The results showed that MI was declined throughout upstream to downstream on both river, as follow: upstream (Cikamal 62.4%; Cirengganis 62.1%), midstream (Cikamal 47.8%; Cirengganis 54,6%), and downstream (Cikamal 38.8%; Cirengganis 34.1%). The number of chromosome aberration types observed were 27 on Cikamal and 10 on Rengganis. The result suggested that Cikamal river has a higher cytotoxicity and genotoxicity level compared to Cirengganis. The Allium marker can serve as the first monitoring system for the presence of cytotoxic and genotoxic pollutant on aquatic environments.