Strategies and Approaches Towards Environmental Biomonitoring of Freshwater Ecosystems in Philippines

The Philippines, like many other Asian countries, is struggling to combat the current widespread aquatic pollution levels caused by anthropogenic activities. Environmental biomonitoring is an efficient tool to detect and monitor the fluctuating toxicity levels in a dynamic ecosystem using bioindicators like algae, macrophytes, zooplankton, insect, bivalve mollusks, gastropod, fish, amphibians, and others to assess the extent and levels of pollution in aquatic ecosystems. The present review deliberates on the biomonitoring techniques such as bioaccumulation, biochemical alterations, population, and community-level approaches to evaluate the current status with respect to the extent and levels of pollution in the aquatic ecosystems in the Philippines which also is one of the biodiversity hotspots. Therefore, the potential applications for biomonitoring are proposed to mainly include evaluation of actual aquatic pollutions, bioremediation, toxicology prediction, and research on toxicological mechanisms. The purpose of such evaluations is to critically analyze and help stakeholders to come up with a strategic action plan with recommendations on a low-cost, sensitive, and effective bioindicator for rapid and efficient environmental biomonitoring.

Can Chitin and Chitosan Replace the Lichen Evernia prunastri for Environmental Biomonitoring of Cu and Zn Air Contamination?

This study compared the ability of the lichen Evernia prunastri, chitin and chitosan to take up Cu2+ and Zn2+. It was hypothesized that chitin and chitosan have an accumulation capacity comparable to the lichen, so that these biopolymers could replace the use of E. prunastri for effective biomonitoring of Cu and Zn air pollution. Samples of the lichen E. prunastri, as well as chitin (from shrimps) and chitosan (from crabs), were incubated with Cu and Zn solutions at concentrations of 0 (control), 10, 25, 50, 75, and 100 µM and analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Metal concentrations accumulated by lichen, chitin and chitosan samples were strongly and linearly correlated with the concentrations in the treatment solutions. The lichen always showed significantly higher accumulation values compared to chitin and chitosan, which showed similar accumulation features. The outcomes of this study confirmed the great effectiveness of the lichen Evernia prunastri for environmental biomonitoring and showed that chitin and chitosan have a lower accumulation capacity, thus suggesting that although these biopolymers have the potential for replacing E. prunastri in polluted areas, their suitability may be limited in areas with intermediate or low pollution levels.