Deliberate oil spills off the coast of the UAE could prove "impossible" to prevent, despite a pledge from the authorities that tanker captains who dump crude-laden ballast water into the sea would feel the weight of the law.
Experts said the sheer volume of sea traffic and complex tide movements may mean that offenders are not traced.
Environment officials have been trying to pinpoint the cause of the oil spills that occurred this week at the Sharjah east coast port of Kalba and last month off the coast of Fujairah.
The kilometres-long slicks forced hotels to close their beaches and threatened marine life.
"Crude oil moves around like crazy in that area, there’s a lot of it being transported by tankers," said Professor Christopher D’Elia, an academic and dean of college of the coast and environment at Louisiana State University.
Having studied the Deepwater Horizon disaster in 2010 and the Exxon-Valdez spill in Alaska in 1989, Prof D’Elia said that currents and winds can carry surface oil great distances from source.
"If you can find out what the prevailing winds in that area and what the currents have been, you can backtrack where it likely came from," he said.
"Finding out the source is very difficult – if not impossible."
According to Hana Al Suwaidi, chairwoman of the Environment and Protected Areas Authority in Sharjah, spills have been caused by tankers dumping oil in ballast discharges.
"The oil slick is caused by the oil spill, which is the release of a liquid petroleum hydrocarbon into the environment, especially marine areas, and it is a form of pollution, requiring an immediate response to control", she said on Monday, adding that there would be "severe repercussions" for those responsible.
But enforcing accountability is a difficult task.
In port and within GCC territorial waters, tankers are covered by federal law to maintain their ballast discharge, used to balance the ship.
But depending on the age of the ship and design, this can be water or oil.
Anywhere within 12 nautical miles of the coast is considered territorial waters of the UAE.
"Contractors must not discharge ballast waste water from their vessels into the marine environment within the coastal limits of UAE territory," according to the regulations set out by Dubai Ports.
In most countries, the coastguard are responsible for enforcing such laws, but fishermen on the east coast said that can be a difficult task.
Fishermen at Khor Kalba Port said that they often witness tankers dumping ballast offshore, and estimated this week’s spillage was six miles offshore – well within UAE waters.
"They make use of the dark and while no one is watching. They wash away the oil into the sea and they should be punished for this criminal act that affects wildlife and humans," said Ahmad Darwish, a 41-year-old Emirati fisherman who fears the economic and environmental effects of the recent spills upon his industry and livelihood.
"When we find oil patches in the water we inform the authorities and they contain it and prevent it from reaching the shores.
"We informed the authorities about this as soon as we saw it, six nautical miles away from the shores, but the wind was fast and it reached the khor in no time.
"We lost this season due to this incident and the bad weather, we need to buy new tools and we hope that the water will be clear soon and the leftovers won’t affect the fish in the future," said Mr Darwish.
Another fisherman, Sultan Al Zaabi, 55, an Emirati, said more needs to be done to prevent the problem.
"I don’t know why they couldn’t control it before it reached the shores, but the effect was very bad this time ... it destroyed our tools, engines and fish," he said.

Source: The National