Agriculture Reference
In-Depth Information
18.3.5 EFFECT OF OZONE ON QUALITY
• Crops like mushroom, seedless cucumber and broccoli stored at
3-10 °C and exposed to O
3
showed min. response to storage tem-
peratures.
• O
3
removes ethylene from environment so useful in closed rooms,
for example, 0.4HL/L O
3
removes 1.5 - 2.0 HL/L Ethylene from
Apple store room.
• O
3
increased Vitamin C and decreased volatiles esters emission in
strawberries
• O
3
has germicidal effect and overall no bad effect observed.
18.4
IMPACTS OF HARMFUL ALGAL BLOOMS
During recent decades, there has been an apparent increase in the occur-
rence of Harmful Algal Blooms (HABs) in many marine and coastal re-
gions (Fig. 18.1; Hallegraeff, 1993). Toxin-producing HAB species are
particularly dangerous to humans. A number of human illnesses are caused
by ingesting seafood (primarily shellfish) contaminated with natural tox-
ins produced by HAB organisms; these include amnesic shellfish poison-
ing (ASP), diarrheic shellfish poisoning (DSP), neurotoxic shellfish poi-
soning (NSP), azaspiracid shellfish poisoning (AZP), paralytic shellfish
poisoning (PSP), and ciguatera fish poisoning. These toxins may cause
respiratory and digestive problems, memory loss, seizures, lesions and
skin irritation, or even fatalities in fish, birds, and mammals (including
humans) (Anderson et al., 2002; Sellner et al., 2003). Some of these tox-
ins can be acutely lethal and are some of the most powerful natural sub-
stances known; additionally, no antidote exists to any HAB toxin (Glibert
et al., 2005). Because these toxins are tasteless, odorless, and heat and acid
stable, normal screening and food preparation procedures will not prevent
intoxication if the fish or shellfish is contaminated (Baden et al., 1995;
Fleming et al., 2006).
In addition to human health effects, HABs also have detrimental eco-
nomic impacts due to closure of commercial fisheries, public health costs
and other related environmental and sociocultural impacts (Trainer and
Suddleson, 2005; NOAA - CSCOR, 2008) (Table 18.3).
