International Journal of Marine Science, 2016, Vol.6, No.9, 1-20
1
Review Article
Open Access
Monitoring of Toxic Pollutants in the Marine Environment- A Review
Mahesh Mohan , Gopikrishna V.G., Navya Cherian, Jyothy S., Toms Augustine, Sreedharan K.
School of Environmental Sciences, Mahatma Gandhi University, Kottayam-686560, India
Corresponding author email:
International Journal of Marine Science, 2016, Vol.6, No.9 doi:
Received: 11 Nov., 2015
Accepted: 24 Mar.,2016
Published:28 Mar., 2016
Copyright © 2016 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:
Mohan M., Gopikrishna V.G., Cherian N., Jyothy S., Augustine T., and Sreedharan K., 2016, Monitoring of Toxic Pollutants in the Marine Environment- A
Review, International Journal of Marine Science, 6(9): 1- 20 (doi:
Abstract
Since the turn of the century, the marine environment is getting adulterated day by day due to several anthropogenic
activities which eventually leads to marine biodiversity loss. Land-based sources play a key role in polluting the marine environment.
The pollutants once entered the marine ecosystem has got a chance to transform chemically or biologically, bioaccumulate or even
biomagnify. Heavy metals, plastics, POPs, radioactive materials and other contaminants contribute much to the marine pollution. The
resultant outcome of this voluminous oceanic pollution is a real threat to the entire biota. This chapter throws light on the various
impacts of toxic pollutants on the marine ecosystems and the effective monitoring possibilities.
Keywords
Marine environment; Ecotoxicology; Toxic pollutants; Heavy metals
1 Introduction
Humans depend on marine ecosystems for a number of valuable goods and services. But human activities has also
altered the marine ecosystems through direct and indirect means leading to marine biodiversity loss which in turn
increasingly impair the ocean's capacity to provide food, maintain water quality, and recover from perturbations
(Worm
et al
., 2006). Until recently, it was widely assumed that no matter how much trash and chemicals humans
dumped into oceans, the effects would be negligible. But recent studies have showed that human activities have
severely affected the marine biodiversity, yet many upper trophic level species, including seabirds, marine
mammals and large predatory fish, remain depleted owing to human activities (Lotze
et al
., 2006). The intensity of
these human activities and their magnitude of impact on the ecological condition of marine communities vary
across the globe (Halpern
et al
.
,
2008). Understanding the sources of pollution and their impacts on ecosystems is
needed to improve and rationalize human activities and to develop appropriate mitigation measures and
management strategies (Islam and Tanaka, 2004).
The majority of the contaminants entering the marine environment are from land-based sources-primarily from
agricultural, urban and industrial sources. Land-based activities cause the runoff of pollutants and nutrients into
coastal waters via rivers and estuaries causing deleterious effect on coastal and marine ecosystems (Syvitski
et al
.,
2005). Atmospheric deposition, spills and dumping of dredging materials also contribute to marine pollution.
Furthermore, ocean-based activities overexploit resources, spread invasive species and diseases, and change
species composition (Crain
et al
., 2009). Indirect human effects on ocean chemistry can also occur, mainly
through global warming and climate change, resulting in increasing sea surface temperatures and ocean
acidification (Doney, 2010). The present paper attempts to provide a review on the major threats from the
pollutants to marine ecosystems with special focus on their sources and their ecosystem-level impacts and how
they can best be monitored.
2 Marine Ecotoxicology - Fate, Transport and impact of pollutants
The understanding of the impact of pollutants on environment is normally based on the toxicological studies with
organisms that can readily be obtained, cultured, and tested, which can be characterized as environmental
toxicology. Although those studies are useful to understand the effects of environmental contaminants on test
organisms individually, the interactions of the species with each other and with the abiotic environment are not
