A Brief Review by:Akbar Tahir

Faculty of Marine Science and Fisheries

University of Hasanuddin

Marine coastal pollution: causes, effects and

management options

Introduction

Marine and Coastal Pollution is defined as the introduction of chemical, physical, or biological material that degrades the quality of the water and sediments and affects the living organisms. This process ranges from simple addition of dissolved or suspended solids to discharge of the most insidious and persistent toxic pollutants (such as pesticides, heavy metals, and non-degradable, bioaccumulative, chemical compounds).

Common Sources of Coastal Pollutants

A large variety of contaminants from industrial, agricultural, urban, and maritime activities are associated with water bodies, sediment particulates, including bottom sediments.

The dredging and disposal of sediment from harbors and hazardous waste sites also contribute significantly to contamination in the coastal zone.

Chemical contaminants discharged into estuaries and coastal waters often attach to sediment particles and are deposited on the sea bed.

Example of Polluting Activities in Marine and Coastal Area

In sufficiently high concentrations, these contaminant-laden waters and sediments may pose serious threats to coastal ecosystems, the sustainability of natural resources, and human health.

Marine and Coastal pollution due to contaminants such as organochlorine pesticides (OCP), polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs) petroleum hydrocarbons (PHCs), polychlorinated dibenzo-dioxins (PCDDs), heavy metals (mercury, cadmium, arsenic, cobalt, manganese, etc.) and nutrient salts, has become a global concern because of the accumulation of their residues in the tissues of various species of marine organisms and their bio-magnification through the food-chain leading to hazards to human health.

In case of nutrients, excessive concentrations of these salts in coastal waters can lead to eutrophication and proliferation of toxic algal blooms. 

Effects of Pollutants in Coastal Area

On the toxics issue, the first decade of the 21st century has brought to light still another challenge — endocrine disrupting compounds (EDCs). Scientific studies have shown a relationship between exposure to EDCs and abnormal thyroid function, sex alteration, poor hatching success, decreased fertility and growth, and altered behavior, especially in aquatic organisms. The main suspected agent was the expired medical supplies those being discharged into municipal waste water treatment.

Heavy metals such as cadmium, mercury, lead, copper, and zinc, are regarded as serious marine pollutants because of their toxicity, tendency to be incorporated into food chains, and ability to remain in an environment for a long time.

Critical habitats and food chains supporting many estuarine fish and wildlife species involve the benthic environment (the sea bottom).

Contaminants in the sediments often pose both ecological and human-health risks through degraded habitats, loss of fauna, propagation of contaminants in the coastal ecosystem, and human consumption of contaminated fish and wildlife.

Contaminated/Polluted Condition

Principles of Marine and Coastal Pollution Management

EnvironmentalMonitoring

Marine biotechnology

Waste treatment

PollutionAssessment

Marine sediments constitute part of the contaminants in aquatic environments. The bottom sediment serves as a reservoir for heavy metals, and therefore, deserves special consideration in the planning and design of aquatic pollution research studies.

Sediment grain size, organic matter content, and chemical composition of different kinds of sediment, as well as the amount and chemical properties of contaminants, influence the levels and extent of contamination in the environment. Contaminant-laden sediments on the sea bottom may be resuspended, transported, and redeposited in areas far from the original source.

Under certain conditions, contaminants may "break free" from sediments (a process known as desorption) and be released into the water, making the bottom sediments not only a sink, but also a source of contaminants.

Possible Management Options

Possible Management Options

Characterizing and delineating areas of sediment contamination and toxicity are viewed as important goals of coastal resource management. This includes the analysis of trends in the environmental quality of coastal ecosystems.

Providing an integrated Municipal Waste Water Treatment, prior to being discharged into the coastal area.

Continously conducting public awareness in terms of pollution abatement (special case for developing countries like Indonesia).

Application of Marine Biotechnology such as Microbiology Bioremediation.

Physical Methods of Wastewater Treatment

Physical Methods of Wastewater Treatment

Primary

treatm

e

nt

Primary

treatm

e

nt

Secondary treatment

Secondary treatment

•Dissolution

•Blending

•Slurring

•Phase separation

Nutrition

Oxidation/Reduction

Precipitation

Adsorption

Extraction

Sedimentation

Municipal Waste Water Treatment Plant

Sediment Contamination and Toxicity Delineation

TERIMA KASIH BANYAK

THANK YOU SO MUCHVIELEN DANK