Environmental Engineering Reference
In-Depth Information
barnacles, and bryozoans is added to enhance the anti-fouling properties. Examples
of this include Irgarol
®
1051 (BASF) and Diuron (Lanxess), copper pyrithione,
isothiazolone, benzmethylamide, luorofolpet, polyphase, pyridone-triphenylborane,
2,3,5,6-tetrachloro-4-(methylsulfonyl) (TCMS),2-(thiocyanomethylthio)
benzothiazoland tolyluanid (
Table 2.5
) [2, 62].The properties of few of these biocides
are described next.
Table 2.4 Commercially available paints and their mode of action
Commercial paints
Manufactures
Biocides
Mechanism of action
• No Foul ZO
• EP 2000
• SN-1
E Paint Company • Zinc Omadine®
• SeaNine211
TM
SP; copper free; prevents grass,
slime, algae, and bacteria
settling and attachment of hard
shell-type organisms
• Globic
• Oceanic
• Olympic
Hempel A/S
−
SP, ion exchange ibres
• Intersmooth
• Interswift
• Interspeed
International
Marine Coatings
−
SP
;
hydrolysis reaction. Copper
acrylate SP technology and
rosin based CDP technology
Irgarol
®
1051 is a herbicide that acts by inhibiting photosynthesis in plants and algae.
It inhibits the photosystem II by interfering with the photosynthetic electron capture
transport in the chloroplasts [69]. Although a very effective biocide, its environmental
effect is uncertain. Irgarol degrades slowly with a half-life of about 100 and 200 days
in fresh and seawater, respectively, [70]. Irgarol
®
concentrations as low as 50ng/l are
also highly toxic to non-target marine algae [2].
Diuron is a non-ionic, and a moderately water soluble compound. It is a substituted
urea-based herbicide that acts as a photosynthesis inhibitor. Although it is reported
to be non-bioaccumulative, there are reports of estuaries in Denmark and Sweden
that are contaminated with it [2]. Negroni and co-workers [71] found no degradation
of Diuron in either aerobic or anaerobic conditions in three months of incubation.
Sea-Nine
TM
211, is a fungicide that has been reported to be highly effective against
slime forming marine bacteria and diatoms. It degrades rapidly in the environment
with a half-life of less than 1 h in aerobic and anaerobic studies. Studies in ish showed
no bioaccumulation of the Sea-Nine
™
211 indicating its safety [72].
