Seaweeds could act as indicators of heavy metal pollution in sea
Iron, manganese and zinc concentrations were high in all the algae species studied in the Gulf of Kutch (Photo: UDEY ISMAIL)
SEAWEEDS (algae) are good indicators of heavy metal levels in marine
environments and could be used for monitoring such pollutants in seas.
According to a new study in the Gulf of Kutch, which receives discharges
containing heavy metals from several industries, various species of
brown, red and green algae accumulate heavy metals from seawater and
sediments. Heavy metals enter various organisms and trigger tissue
damage.
They generate reactive oxygen species, such as hydrogen peroxide,
which break down proteins and lipids, degrade DNA, and cause cell
deaths.
The study was conducted at Vadinar and Sikka in the Gulf of Kutch. In
recent years, such coastal regions have seen rapid industrialisation.
The researchers measured the levels of heavy metals in various species
of red, brown and green algae, in seawater and sediments and found that
iron, manganese and zinc concentrations were generally high in all the
algae species. Large amounts of cadmium and zinc were also found.
The highest concentrations of iron and zinc were found in green algae
Ulva lactuca and the lowest iron concentration was recorded in red
algae Gracilaria verrucosa at Vadinar. Green algae Caulerpa
scalpeliformis accumulated considerable amounts of manganese at Vadinar.
At Sikka, it was found accumulated with large quantities of cadmium and
chromium. The highest and lowest concentrations of lead were found in
the green algae. The study also found that cadmium was accumulated most
by brown algae Padina gymnospora.
“People feeding on marine plants and fish might be affected by such
heavy metals. Since human beings are secondary consumers, their chances
of getting affected by these are high,” says Jyoti Prakash Maity from
the National Chung Cheng University, Taiwan. The studied algae are
abundant in the Gulf of Kutch and can be used as a biomonitor for heavy
metal pollution, adds Maity. According to the US’ Environment Protection
Agency, cadmium is carcinogenic and affects heart, lungs and
reproductive system while lead can damage the brain and nervous system.
Chrom ium causes lung cancer and manganese can make muscles stiff.
Researchers from the Birla Institute of Technology, Ranchi,
Jharkhand; the National Centre for Sustainable Coastal Management,
Chennai; and National Chung Cheng University, Taiwan, conducted the
study. The results have been published in the February issue of Eco
toxicology and Environmental Safety.
