Africa Water, Sanitation & Hygiene September 2018 Vol.13 No.4 | Page 10

NEWS in brief
Global Highlights
according to the World. The most affected countries are
Bangladesh, India, Nepal and Pakistan though arsenic
pollution is also present in China, parts of Europe and the
Americas.
Treatments to remove arsenic contamination, mostly
associated with water drawn from deep, subterranean
sources using borewells, include the use of lime, various
coagulants, osmotic membrane filters or ion exchange
processes.
George Washington University.
Not only have hundreds of villages been abandoned to
escape drought, but many of the same people are on the
run from Boko Haram, the Islamic terrorist group that
has waged an insurgency against the Nigeria state since
2010. “Lack of water in the areas where people have been
pushed into has really weakened the resilience of these
populations to further attacks by Boko Haram,” said King.
Meanwhile, in the south of the country, conflict has
re-emerged in the Niger Delta. The primary ecological
concern for the region is man-made, said King. Spills
from oil and natural gas extraction and violent opposition
by rebels have degraded the water, agricultural land, and
fisheries. The Niger Delta Vigilante group has attacked oil
company infrastructure and personnel, calling for better
provision of clean water and equitable rights, King said,
but “ironically these attacks also frequently cause severe
pollution of the same water resources that they were
seeking to protect to begin with.”
These conflicts matter to the United States because Nigeria
is a “linchpin of regional stability and a strategic partner
in the fight against extremism,” said King. Nigeria is
Africa’s most populous country and a major contributor
to international peacekeeping operations. The instability
in the north of the country in particular is having ripple
effects beyond its borders and into Europe, contributing
to a “migratory arc of instability stretching from West
Africa through the Maghreb and eventually across the
Mediterranean Sea,” said King.
While several methods of ridding water of arsenic have
been devised, cost has been a determining factor in actual
deployment. The researchers, who published their findings
last month (July) in Science of the Total Environment,
claim that their watermelon rind technology is among the
cheapest developed so far.
“Watermelon rind is free. It’s basically bio-waste,
abundantly produced in Pakistan,” says Nabeel Khan
Niazi, assistant professor at the University of Agriculture
Faisalabad (UAF) and a co-author of the paper.
The researchers treated watermelon rind with xanthate
salts — which attract and bind arsenic — to produce a
filter capable of removing 95 per cent of arsenic from
water samples taken from around Pakistan. Xanthates are
produced when alcohol reacts with sodium or potassium
hydroxide and carbon disulphide.
A filter prototype developed by the researchers processes
around 20 litres of water a day. Each filter lasts 6—8
months and costs about US$32, says Niazi. His team won
funding from Grand Challenges Canada in 2014 to develop
the technology.
“We are focusing on poor people who don’t have electricity
or enough money to spend on very fancy filters —
traditional filters can cost around US$200,” says Niazi.
Source: Wilson Center
Watermelon rind a cheap filter for arsenic in
grou