Ships’ Ballast Water Treatment by Chlorination Can Generate Toxic Trihalomethanes

Abstract

The International Maritime Organization (IMO) will enforce a new abundance-based performance standard for ballast water in September, 2017. Strong oxidants, like chlorine, have been proposed as a method for achieving this standard. However chlorine treatment of ballast water can produce hazardous trihalomethanes. We assessed maximum trihalomethane production from one chlorine dose for three types of ballast water (fresh, brackish and marine) and three levels of total organic carbon (TOC) concentration (natural, filtered, enhanced). While the current standard test considers a 5 day voyage, there is a high possibility of shorter trips and sudden change of plans that will release treated waters in the environment. Water source and TOC significantly affected trihalomethane production, with the highest amounts generated in brackish waters and enhanced TOC concentration. The concentration of brominated trihalomethanes increased from background levels and was highest in brackish water, followed by marine and fresh water.

The Impact of Microorganisms Transported in Ships’ Ballast Water on the Fish of the Estuarine Waters and Environmental Sustainability in the Southern Baltic Sea

“…Ballast water constitutes a distinct habitat whose environmental conditions shape the composition of a unique microbiota [4]. Firstly, subjecting it to ballast water treatment processes and associated byproduct formation facilitates the acclimatization and survival of microorganisms until the next tank exchange in new areas [5]. Microbial communities exhibit varying nutritional preferences, with some adept at utilizing carbon compounds while others rely more on carbohydrates, carboxylic acids, hydrocarbons, or amino acids [5,6].…”

“…Firstly, subjecting it to ballast water treatment processes and associated byproduct formation facilitates the acclimatization and survival of microorganisms until the next tank exchange in new areas [5]. Microbial communities exhibit varying nutritional preferences, with some adept at utilizing carbon compounds while others rely more on carbohydrates, carboxylic acids, hydrocarbons, or amino acids [5,6]. Shipboard ballast water treatment systems modify the chemical composition and availability of organic matter crucial for the proliferation of microorganisms inhabiting ballast tanks.…”

Antibacterial ultrafiltration membrane with silver nanoparticle impregnation by interfacial polymerization for ballast water

“…Ballast water is pumped into the ship ballast tanks to provide adequate stability and structural integrity to ships as they discharge cargo 1,2 . Ballasting and deballasting processes can transfer nearly 5 billion tons of ballast water every year 3 .…”

“…Feasible processes or methodologies need to be adopted to treat ballast water containing harmful organisms. A number of ballast water treatment methods on board the ships include physical (filtration, ultraviolet radiation, ultrasound, thermal, magnetic, and electrical treatment) 4 and chemical (ozone, biocides, chlorine, hydrogen peroxide, Ag ion, and peroxyacetic acid) methods 2 . Among these methods, some will consume large amounts of energy while others will need high concentrations to kill toxic organisms effectively.…”