Oil and gas companies take environmental measures at sea. Shipping companies, by contrast, have to be forced to do so.
Van Leeuwen has been struck by the way, after the sinking of the Deep Horizon oil rig in the Gulf of Mexico, BP immediately laid its hand on its heart and took full responsibility for the pollution and the costs of cleaning it up. Van Leeuwen: 'Countries benefit from oil production too of course. Governments could also help pay for the clean-up.'
On the North Sea, there has been good collaboration between governments and the oil and gas industries for years, says Van Leeuwen. Companies take a lot of responsibility, make rules themselves and see to their enforcement too. 'And yet that doesn't take away from the government's authority. Because companies are transparent in the way they work, the government keeps control.'
It's a different picture in the shipping industry. Shipping companies don't take the environment so seriously and are therefore being subjected to closer and closer supervision by governments, says Van Leeuwen. So how come the oil industry protects the environment itself while the shipping industry requires strict government supervision? 'Oil companies have a strong public image. That image can be damaged, which can have consequences for the company. Look at the damage done to Shell by the Brent Spar disaster. Shipping companies are smaller and are not known to the general public, so it is not important to them to keep up a good image.'