Earth Day and Earth Hour was jointly celebrated in Israel on Thursday. Six cities turned off their lights for an hour in a symbolic gesture to raise awareness to the dangers of global warming - Tel Aviv at 8 p.m., Jerusalem at 8:10, Haifa at 8:20, Beersheba and Dimona at 8:30 and Kfar Saba at 8:40. Jerusalem held a non-energy using pyrotechnics show over the Old City walls while the lights were out. During the afternoon, there was a fair next to the Old City walls in conjunction with the Society for the Protection of Nature in Israel. In Tel Aviv, SPNI held events at community gardens as well as its annual Children and Youth conference. And in the quirkiest Earth Day event in Israel, the National Lottery was funding the running of the Balkan Beat Box concert on used felafel oil. A team of 24 professional cyclists were pedaling bikes connected to a generator that runs on used felafel oil. The alternative energy source was providing electricity for the entire concert held in Tel Aviv's Kikkar Rabin while the lights were out. On Wednesday, environmental law expert Tzvi Levinson told The Jerusalem Post that Israeli companies may be forced to adhere to higher environmental standards if they wish to compete in global markets. Founding partner of the Haifa-based Levinson Environmental law firm, Levinson has focused on environmental law for two decades. If Israeli companies want to compete in Europe, then they will have to start worrying about how green their manufacturing processes and their products are, Levinson said. "While Europe can't dictate to Israel, they can decide what products are sold in Europe and which aren't. Today, not only is Europe interested in how the product was made, but in the product itself. Companies might find that they will now be faced with demands to make their products using less chemicals or recyclable," he said. Europe has taken a global lead in setting such environmental standards for products, but the US could be catching up or even surpass them, according to Levinson. "Most of the standards were reduced to almost nothing during US president George W. Bush's tenure, but now that President Obama has taken office, people are looking to see what he'll do," he said. Much of Israeli environmental law includes explicit reference to international standards and treaties, to which Israelis will now have to adhere, he added. "Perhaps more than in other fields of law, local environmental law relies heavily on international environmental treaties and laws," he said. Many of the new laws, including the Clean Air Act, include specific mention of global standards. In fact, some environmental laws have been imported wholesale out of other country's law books, according to Levinson. This posed a problem because they hadn't been adapted to local conditions. "Some of the requirements are too strict for Israeli companies to accomplish right now, which leads to them brushing them off rather than seeking to comply with a more reasonable standard," he said. While Israeli law should look to international law for inspiration, it should always be crafted with an eye to the domestic context, he urged. Regarding global warming, while there was no current legislation regulating emissions, the new Clean Air Act actually defined Israel as a developed nation rather than a developing one. Internationally, Israeli is still considered a developing nation. "The new Clean Air Act, which is set to go into effect in 2011, actually refers to greenhouse gases as pollution and places Israel de facto squarely into the category of developed nation. So even before Israel is considered a developed nation and obligated by the post-Kyoto Protocol set to begin in 2012, it will have declared itself a developed nation," he said. Earth Day has been celebrated internationally on April 22 since 1970. In Israel, it was moved one day later because its observance cannot immediately follow Holocaust Remembrance Day. Earth Hour was celebrated last month on a Saturday around the world, but Israel asked and received permission to delay it to a non-Shabbat day. Former Wisconsin senator Gaylord Nelson, a staunch environmentalist, founded Earth Day as a teach-in in 1970. He passed away in 2005.